* simplify the mdev interface v5
@ 2022-07-06 7:42 Christoph Hellwig
2022-07-06 7:42 ` [PATCH 01/15] drm/i915/gvt: fix a memory leak in intel_gvt_init_vgpu_types Christoph Hellwig
` (14 more replies)
0 siblings, 15 replies; 31+ messages in thread
From: Christoph Hellwig @ 2022-07-06 7:42 UTC (permalink / raw)
To: Kirti Wankhede, Tony Krowiak, Halil Pasic, Jason Herne,
Eric Farman, Matthew Rosato, Zhenyu Wang, Zhi Wang,
Alex Williamson
Cc: Jason Gunthorpe, kvm, linux-s390, intel-gvt-dev
Hi all,
this series signigicantly simplies the mdev driver interface by following
the patterns for device model interaction used elsewhere in the kernel.
Changes since v4:
- move the kobject_put later in mdev_device_release
- add a Fixes tag for the first patch
- add another patch to remove an extra kobject_get/put
Changes since v3:
- make the sysfs_name and pretty_name fields pointers instead of arrays
- add an i915 cleanup to prepare for the above
Changes since v2:
- rebased to vfio/next
- fix a pre-existing memory leak in i915 instead of making it worse
- never manipulate if ->available_instances if drv->get_available is
provided
- keep a parent reference for the mdev_type
- keep a few of the sysfs.c helper function around
- improve the documentation for the parent device lifetime
- minor spellig / formatting fixes
Changes since v1:
- embedd the mdev_parent into a different sub-structure in i916
- remove headers now inclued by mdev.h from individual source files
- pass an array of mdev_types to mdev_register_parent
- add additional patches to implement all attributes on the
mdev_type in the core code
Diffstat:
Documentation/driver-api/vfio-mediated-device.rst | 26 +-
Documentation/s390/vfio-ap.rst | 2
Documentation/s390/vfio-ccw.rst | 2
drivers/gpu/drm/i915/gvt/aperture_gm.c | 20 +-
drivers/gpu/drm/i915/gvt/gvt.h | 42 ++--
drivers/gpu/drm/i915/gvt/kvmgt.c | 168 ++++-------------
drivers/gpu/drm/i915/gvt/vgpu.c | 210 +++++++---------------
drivers/s390/cio/cio.h | 4
drivers/s390/cio/vfio_ccw_drv.c | 3
drivers/s390/cio/vfio_ccw_ops.c | 60 ------
drivers/s390/cio/vfio_ccw_private.h | 2
drivers/s390/crypto/vfio_ap_ops.c | 68 +------
drivers/s390/crypto/vfio_ap_private.h | 6
drivers/vfio/mdev/mdev_core.c | 191 ++++----------------
drivers/vfio/mdev/mdev_driver.c | 7
drivers/vfio/mdev/mdev_private.h | 32 ---
drivers/vfio/mdev/mdev_sysfs.c | 189 ++++++++++---------
include/linux/mdev.h | 77 ++++----
samples/vfio-mdev/mbochs.c | 103 +++-------
samples/vfio-mdev/mdpy.c | 115 +++---------
samples/vfio-mdev/mtty.c | 94 +++------
21 files changed, 459 insertions(+), 962 deletions(-)
^ permalink raw reply [flat|nested] 31+ messages in thread
* [PATCH 01/15] drm/i915/gvt: fix a memory leak in intel_gvt_init_vgpu_types
2022-07-06 7:42 simplify the mdev interface v5 Christoph Hellwig
@ 2022-07-06 7:42 ` Christoph Hellwig
2022-07-06 7:42 ` [PATCH 02/15] drm/i915/gvt: simplify vgpu configuration management Christoph Hellwig
` (13 subsequent siblings)
14 siblings, 0 replies; 31+ messages in thread
From: Christoph Hellwig @ 2022-07-06 7:42 UTC (permalink / raw)
To: Kirti Wankhede, Tony Krowiak, Halil Pasic, Jason Herne,
Eric Farman, Matthew Rosato, Zhenyu Wang, Zhi Wang,
Alex Williamson
Cc: Jason Gunthorpe, kvm, linux-s390, intel-gvt-dev, Kevin Tian
gvt->types needs to be freed on error.
Fixes: c90d097ae144 ("drm/i915/gvt: define weight according to vGPU type")
Reported-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Zhenyu Wang <zhenyuw@linux.intel.com>
---
drivers/gpu/drm/i915/gvt/vgpu.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/gvt/vgpu.c b/drivers/gpu/drm/i915/gvt/vgpu.c
index 46da19b3225d2..5c828556cefd7 100644
--- a/drivers/gpu/drm/i915/gvt/vgpu.c
+++ b/drivers/gpu/drm/i915/gvt/vgpu.c
@@ -142,7 +142,7 @@ int intel_gvt_init_vgpu_types(struct intel_gvt *gvt)
if (vgpu_types[i].weight < 1 ||
vgpu_types[i].weight > VGPU_MAX_WEIGHT)
- return -EINVAL;
+ goto out_free_types;
gvt->types[i].weight = vgpu_types[i].weight;
gvt->types[i].resolution = vgpu_types[i].edid;
@@ -167,6 +167,10 @@ int intel_gvt_init_vgpu_types(struct intel_gvt *gvt)
gvt->num_types = i;
return 0;
+
+out_free_types:
+ kfree(gvt->types);
+ return -EINVAL;
}
void intel_gvt_clean_vgpu_types(struct intel_gvt *gvt)
--
2.30.2
^ permalink raw reply related [flat|nested] 31+ messages in thread
* [PATCH 02/15] drm/i915/gvt: simplify vgpu configuration management
2022-07-06 7:42 simplify the mdev interface v5 Christoph Hellwig
2022-07-06 7:42 ` [PATCH 01/15] drm/i915/gvt: fix a memory leak in intel_gvt_init_vgpu_types Christoph Hellwig
@ 2022-07-06 7:42 ` Christoph Hellwig
2022-07-07 2:18 ` Tian, Kevin
2022-07-06 7:42 ` [PATCH 03/15] vfio/mdev: make mdev.h standalone includable Christoph Hellwig
` (12 subsequent siblings)
14 siblings, 1 reply; 31+ messages in thread
From: Christoph Hellwig @ 2022-07-06 7:42 UTC (permalink / raw)
To: Kirti Wankhede, Tony Krowiak, Halil Pasic, Jason Herne,
Eric Farman, Matthew Rosato, Zhenyu Wang, Zhi Wang,
Alex Williamson
Cc: Jason Gunthorpe, kvm, linux-s390, intel-gvt-dev
Instead of copying the information from the vgpu_types arrays into each
intel_vgpu_type structure, just reference this constant information
with a pointer to the already existing data structure, and pass it into
the low-level VGPU creation helpers intead of copying the data into yet
anothe params data structure.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Zhenyu Wang <zhenyuw@linux.intel.com>
---
drivers/gpu/drm/i915/gvt/aperture_gm.c | 20 +--
drivers/gpu/drm/i915/gvt/gvt.h | 36 +++---
drivers/gpu/drm/i915/gvt/kvmgt.c | 10 +-
drivers/gpu/drm/i915/gvt/vgpu.c | 172 +++++++++----------------
4 files changed, 91 insertions(+), 147 deletions(-)
diff --git a/drivers/gpu/drm/i915/gvt/aperture_gm.c b/drivers/gpu/drm/i915/gvt/aperture_gm.c
index 557f3314291a8..7dd8163f8a569 100644
--- a/drivers/gpu/drm/i915/gvt/aperture_gm.c
+++ b/drivers/gpu/drm/i915/gvt/aperture_gm.c
@@ -240,13 +240,13 @@ static void free_resource(struct intel_vgpu *vgpu)
}
static int alloc_resource(struct intel_vgpu *vgpu,
- struct intel_vgpu_creation_params *param)
+ const struct intel_vgpu_config *conf)
{
struct intel_gvt *gvt = vgpu->gvt;
unsigned long request, avail, max, taken;
const char *item;
- if (!param->low_gm_sz || !param->high_gm_sz || !param->fence_sz) {
+ if (!conf->low_mm || !conf->high_mm || !conf->fence) {
gvt_vgpu_err("Invalid vGPU creation params\n");
return -EINVAL;
}
@@ -255,7 +255,7 @@ static int alloc_resource(struct intel_vgpu *vgpu,
max = gvt_aperture_sz(gvt) - HOST_LOW_GM_SIZE;
taken = gvt->gm.vgpu_allocated_low_gm_size;
avail = max - taken;
- request = MB_TO_BYTES(param->low_gm_sz);
+ request = conf->low_mm;
if (request > avail)
goto no_enough_resource;
@@ -266,7 +266,7 @@ static int alloc_resource(struct intel_vgpu *vgpu,
max = gvt_hidden_sz(gvt) - HOST_HIGH_GM_SIZE;
taken = gvt->gm.vgpu_allocated_high_gm_size;
avail = max - taken;
- request = MB_TO_BYTES(param->high_gm_sz);
+ request = conf->high_mm;
if (request > avail)
goto no_enough_resource;
@@ -277,16 +277,16 @@ static int alloc_resource(struct intel_vgpu *vgpu,
max = gvt_fence_sz(gvt) - HOST_FENCE;
taken = gvt->fence.vgpu_allocated_fence_num;
avail = max - taken;
- request = param->fence_sz;
+ request = conf->fence;
if (request > avail)
goto no_enough_resource;
vgpu_fence_sz(vgpu) = request;
- gvt->gm.vgpu_allocated_low_gm_size += MB_TO_BYTES(param->low_gm_sz);
- gvt->gm.vgpu_allocated_high_gm_size += MB_TO_BYTES(param->high_gm_sz);
- gvt->fence.vgpu_allocated_fence_num += param->fence_sz;
+ gvt->gm.vgpu_allocated_low_gm_size += conf->low_mm;
+ gvt->gm.vgpu_allocated_high_gm_size += conf->high_mm;
+ gvt->fence.vgpu_allocated_fence_num += conf->fence;
return 0;
no_enough_resource:
@@ -340,11 +340,11 @@ void intel_vgpu_reset_resource(struct intel_vgpu *vgpu)
*
*/
int intel_vgpu_alloc_resource(struct intel_vgpu *vgpu,
- struct intel_vgpu_creation_params *param)
+ const struct intel_vgpu_config *conf)
{
int ret;
- ret = alloc_resource(vgpu, param);
+ ret = alloc_resource(vgpu, conf);
if (ret)
return ret;
diff --git a/drivers/gpu/drm/i915/gvt/gvt.h b/drivers/gpu/drm/i915/gvt/gvt.h
index aee1a45da74bc..392c2ad49d376 100644
--- a/drivers/gpu/drm/i915/gvt/gvt.h
+++ b/drivers/gpu/drm/i915/gvt/gvt.h
@@ -295,15 +295,26 @@ struct intel_gvt_firmware {
bool firmware_loaded;
};
+struct intel_vgpu_config {
+ unsigned int low_mm;
+ unsigned int high_mm;
+ unsigned int fence;
+
+ /*
+ * A vGPU with a weight of 8 will get twice as much GPU as a vGPU with
+ * a weight of 4 on a contended host, different vGPU type has different
+ * weight set. Legal weights range from 1 to 16.
+ */
+ unsigned int weight;
+ enum intel_vgpu_edid edid;
+ const char *name;
+};
+
#define NR_MAX_INTEL_VGPU_TYPES 20
struct intel_vgpu_type {
char name[16];
+ const struct intel_vgpu_config *conf;
unsigned int avail_instance;
- unsigned int low_gm_size;
- unsigned int high_gm_size;
- unsigned int fence;
- unsigned int weight;
- enum intel_vgpu_edid resolution;
};
struct intel_gvt {
@@ -437,19 +448,8 @@ int intel_gvt_load_firmware(struct intel_gvt *gvt);
/* ring context size i.e. the first 0x50 dwords*/
#define RING_CTX_SIZE 320
-struct intel_vgpu_creation_params {
- __u64 low_gm_sz; /* in MB */
- __u64 high_gm_sz; /* in MB */
- __u64 fence_sz;
- __u64 resolution;
- __s32 primary;
- __u64 vgpu_id;
-
- __u32 weight;
-};
-
int intel_vgpu_alloc_resource(struct intel_vgpu *vgpu,
- struct intel_vgpu_creation_params *param);
+ const struct intel_vgpu_config *conf);
void intel_vgpu_reset_resource(struct intel_vgpu *vgpu);
void intel_vgpu_free_resource(struct intel_vgpu *vgpu);
void intel_vgpu_write_fence(struct intel_vgpu *vgpu,
@@ -496,7 +496,7 @@ void intel_gvt_clean_vgpu_types(struct intel_gvt *gvt);
struct intel_vgpu *intel_gvt_create_idle_vgpu(struct intel_gvt *gvt);
void intel_gvt_destroy_idle_vgpu(struct intel_vgpu *vgpu);
struct intel_vgpu *intel_gvt_create_vgpu(struct intel_gvt *gvt,
- struct intel_vgpu_type *type);
+ const struct intel_vgpu_config *conf);
void intel_gvt_destroy_vgpu(struct intel_vgpu *vgpu);
void intel_gvt_release_vgpu(struct intel_vgpu *vgpu);
void intel_gvt_reset_vgpu_locked(struct intel_vgpu *vgpu, bool dmlr,
diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
index e2f6c56ab3420..7b060c0e66ae7 100644
--- a/drivers/gpu/drm/i915/gvt/kvmgt.c
+++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
@@ -151,10 +151,10 @@ static ssize_t description_show(struct mdev_type *mtype,
return sprintf(buf, "low_gm_size: %dMB\nhigh_gm_size: %dMB\n"
"fence: %d\nresolution: %s\n"
"weight: %d\n",
- BYTES_TO_MB(type->low_gm_size),
- BYTES_TO_MB(type->high_gm_size),
- type->fence, vgpu_edid_str(type->resolution),
- type->weight);
+ BYTES_TO_MB(type->conf->low_mm),
+ BYTES_TO_MB(type->conf->high_mm),
+ type->conf->fence, vgpu_edid_str(type->conf->edid),
+ type->conf->weight);
}
static ssize_t name_show(struct mdev_type *mtype,
@@ -1624,7 +1624,7 @@ static int intel_vgpu_probe(struct mdev_device *mdev)
if (!type)
return -EINVAL;
- vgpu = intel_gvt_create_vgpu(gvt, type);
+ vgpu = intel_gvt_create_vgpu(gvt, type->conf);
if (IS_ERR(vgpu)) {
gvt_err("failed to create intel vgpu: %ld\n", PTR_ERR(vgpu));
return PTR_ERR(vgpu);
diff --git a/drivers/gpu/drm/i915/gvt/vgpu.c b/drivers/gpu/drm/i915/gvt/vgpu.c
index 5c828556cefd7..8e136dcc70112 100644
--- a/drivers/gpu/drm/i915/gvt/vgpu.c
+++ b/drivers/gpu/drm/i915/gvt/vgpu.c
@@ -73,24 +73,21 @@ void populate_pvinfo_page(struct intel_vgpu *vgpu)
drm_WARN_ON(&i915->drm, sizeof(struct vgt_if) != VGT_PVINFO_SIZE);
}
+/*
+ * vGPU type name is defined as GVTg_Vx_y which contains the physical GPU
+ * generation type (e.g V4 as BDW server, V5 as SKL server).
+ *
+ * Depening on the physical SKU resource, we might see vGPU types like
+ * GVTg_V4_8, GVTg_V4_4, GVTg_V4_2, etc. We can create different types of
+ * vGPU on same physical GPU depending on available resource. Each vGPU
+ * type will have a different number of avail_instance to indicate how
+ * many vGPU instance can be created for this type.
+ */
#define VGPU_MAX_WEIGHT 16
#define VGPU_WEIGHT(vgpu_num) \
(VGPU_MAX_WEIGHT / (vgpu_num))
-static const struct {
- unsigned int low_mm;
- unsigned int high_mm;
- unsigned int fence;
-
- /* A vGPU with a weight of 8 will get twice as much GPU as a vGPU
- * with a weight of 4 on a contended host, different vGPU type has
- * different weight set. Legal weights range from 1 to 16.
- */
- unsigned int weight;
- enum intel_vgpu_edid edid;
- const char *name;
-} vgpu_types[] = {
-/* Fixed vGPU type table */
+static const struct intel_vgpu_config intel_vgpu_configs[] = {
{ MB_TO_BYTES(64), MB_TO_BYTES(384), 4, VGPU_WEIGHT(8), GVT_EDID_1024_768, "8" },
{ MB_TO_BYTES(128), MB_TO_BYTES(512), 4, VGPU_WEIGHT(4), GVT_EDID_1920_1200, "4" },
{ MB_TO_BYTES(256), MB_TO_BYTES(1024), 4, VGPU_WEIGHT(2), GVT_EDID_1920_1200, "2" },
@@ -106,63 +103,34 @@ static const struct {
*/
int intel_gvt_init_vgpu_types(struct intel_gvt *gvt)
{
- unsigned int num_types;
- unsigned int i, low_avail, high_avail;
- unsigned int min_low;
-
- /* vGPU type name is defined as GVTg_Vx_y which contains
- * physical GPU generation type (e.g V4 as BDW server, V5 as
- * SKL server).
- *
- * Depend on physical SKU resource, might see vGPU types like
- * GVTg_V4_8, GVTg_V4_4, GVTg_V4_2, etc. We can create
- * different types of vGPU on same physical GPU depending on
- * available resource. Each vGPU type will have "avail_instance"
- * to indicate how many vGPU instance can be created for this
- * type.
- *
- */
- low_avail = gvt_aperture_sz(gvt) - HOST_LOW_GM_SIZE;
- high_avail = gvt_hidden_sz(gvt) - HOST_HIGH_GM_SIZE;
- num_types = ARRAY_SIZE(vgpu_types);
+ unsigned int low_avail = gvt_aperture_sz(gvt) - HOST_LOW_GM_SIZE;
+ unsigned int high_avail = gvt_hidden_sz(gvt) - HOST_HIGH_GM_SIZE;
+ unsigned int num_types = ARRAY_SIZE(intel_vgpu_configs);
+ unsigned int i;
gvt->types = kcalloc(num_types, sizeof(struct intel_vgpu_type),
GFP_KERNEL);
if (!gvt->types)
return -ENOMEM;
- min_low = MB_TO_BYTES(32);
for (i = 0; i < num_types; ++i) {
- if (low_avail / vgpu_types[i].low_mm == 0)
- break;
-
- gvt->types[i].low_gm_size = vgpu_types[i].low_mm;
- gvt->types[i].high_gm_size = vgpu_types[i].high_mm;
- gvt->types[i].fence = vgpu_types[i].fence;
+ const struct intel_vgpu_config *conf = &intel_vgpu_configs[i];
- if (vgpu_types[i].weight < 1 ||
- vgpu_types[i].weight > VGPU_MAX_WEIGHT)
+ if (low_avail / conf->low_mm == 0)
+ break;
+ if (conf->weight < 1 || conf->weight > VGPU_MAX_WEIGHT)
goto out_free_types;
- gvt->types[i].weight = vgpu_types[i].weight;
- gvt->types[i].resolution = vgpu_types[i].edid;
- gvt->types[i].avail_instance = min(low_avail / vgpu_types[i].low_mm,
- high_avail / vgpu_types[i].high_mm);
-
- if (GRAPHICS_VER(gvt->gt->i915) == 8)
- sprintf(gvt->types[i].name, "GVTg_V4_%s",
- vgpu_types[i].name);
- else if (GRAPHICS_VER(gvt->gt->i915) == 9)
- sprintf(gvt->types[i].name, "GVTg_V5_%s",
- vgpu_types[i].name);
+ sprintf(gvt->types[i].name, "GVTg_V%u_%s",
+ GRAPHICS_VER(gvt->gt->i915) == 8 ? 4 : 5, conf->name);
+ gvt->types->conf = conf;
+ gvt->types[i].avail_instance = min(low_avail / conf->low_mm,
+ high_avail / conf->high_mm);
gvt_dbg_core("type[%d]: %s avail %u low %u high %u fence %u weight %u res %s\n",
- i, gvt->types[i].name,
- gvt->types[i].avail_instance,
- gvt->types[i].low_gm_size,
- gvt->types[i].high_gm_size, gvt->types[i].fence,
- gvt->types[i].weight,
- vgpu_edid_str(gvt->types[i].resolution));
+ i, gvt->types[i].name, gvt->types[i].avail_instance,
+ conf->low_mm, conf->high_mm, conf->fence,
+ conf->weight, vgpu_edid_str(conf->edid));
}
gvt->num_types = i;
@@ -195,16 +163,16 @@ static void intel_gvt_update_vgpu_types(struct intel_gvt *gvt)
gvt->fence.vgpu_allocated_fence_num;
for (i = 0; i < gvt->num_types; i++) {
- low_gm_min = low_gm_avail / gvt->types[i].low_gm_size;
- high_gm_min = high_gm_avail / gvt->types[i].high_gm_size;
- fence_min = fence_avail / gvt->types[i].fence;
+ low_gm_min = low_gm_avail / gvt->types[i].conf->low_mm;
+ high_gm_min = high_gm_avail / gvt->types[i].conf->high_mm;
+ fence_min = fence_avail / gvt->types[i].conf->fence;
gvt->types[i].avail_instance = min(min(low_gm_min, high_gm_min),
fence_min);
gvt_dbg_core("update type[%d]: %s avail %u low %u high %u fence %u\n",
i, gvt->types[i].name,
- gvt->types[i].avail_instance, gvt->types[i].low_gm_size,
- gvt->types[i].high_gm_size, gvt->types[i].fence);
+ gvt->types[i].avail_instance, gvt->types[i].conf->low_mm,
+ gvt->types[i].conf->high_mm, gvt->types[i].conf->fence);
}
}
@@ -367,42 +335,53 @@ void intel_gvt_destroy_idle_vgpu(struct intel_vgpu *vgpu)
vfree(vgpu);
}
-static struct intel_vgpu *__intel_gvt_create_vgpu(struct intel_gvt *gvt,
- struct intel_vgpu_creation_params *param)
+/**
+ * intel_gvt_create_vgpu - create a virtual GPU
+ * @gvt: GVT device
+ * @conf: type of the vGPU to create
+ *
+ * This function is called when user wants to create a virtual GPU.
+ *
+ * Returns:
+ * pointer to intel_vgpu, error pointer if failed.
+ */
+struct intel_vgpu *intel_gvt_create_vgpu(struct intel_gvt *gvt,
+ const struct intel_vgpu_config *conf)
{
struct drm_i915_private *dev_priv = gvt->gt->i915;
struct intel_vgpu *vgpu;
int ret;
- gvt_dbg_core("low %llu MB high %llu MB fence %llu\n",
- param->low_gm_sz, param->high_gm_sz,
- param->fence_sz);
+ gvt_dbg_core("low %u MB high %u MB fence %u\n",
+ BYTES_TO_MB(conf->low_mm), BYTES_TO_MB(conf->high_mm),
+ conf->fence);
vgpu = vzalloc(sizeof(*vgpu));
if (!vgpu)
return ERR_PTR(-ENOMEM);
+ mutex_lock(&gvt->lock);
ret = idr_alloc(&gvt->vgpu_idr, vgpu, IDLE_VGPU_IDR + 1, GVT_MAX_VGPU,
GFP_KERNEL);
if (ret < 0)
- goto out_free_vgpu;
+ goto out_unlock;;
vgpu->id = ret;
vgpu->gvt = gvt;
- vgpu->sched_ctl.weight = param->weight;
+ vgpu->sched_ctl.weight = conf->weight;
mutex_init(&vgpu->vgpu_lock);
mutex_init(&vgpu->dmabuf_lock);
INIT_LIST_HEAD(&vgpu->dmabuf_obj_list_head);
INIT_RADIX_TREE(&vgpu->page_track_tree, GFP_KERNEL);
idr_init_base(&vgpu->object_idr, 1);
- intel_vgpu_init_cfg_space(vgpu, param->primary);
+ intel_vgpu_init_cfg_space(vgpu, 1);
vgpu->d3_entered = false;
ret = intel_vgpu_init_mmio(vgpu);
if (ret)
goto out_clean_idr;
- ret = intel_vgpu_alloc_resource(vgpu, param);
+ ret = intel_vgpu_alloc_resource(vgpu, conf);
if (ret)
goto out_clean_vgpu_mmio;
@@ -416,7 +395,7 @@ static struct intel_vgpu *__intel_gvt_create_vgpu(struct intel_gvt *gvt,
if (ret)
goto out_clean_gtt;
- ret = intel_vgpu_init_display(vgpu, param->resolution);
+ ret = intel_vgpu_init_display(vgpu, conf->edid);
if (ret)
goto out_clean_opregion;
@@ -441,6 +420,9 @@ static struct intel_vgpu *__intel_gvt_create_vgpu(struct intel_gvt *gvt,
if (ret)
goto out_clean_sched_policy;
+ intel_gvt_update_vgpu_types(gvt);
+ intel_gvt_update_reg_whitelist(vgpu);
+ mutex_unlock(&gvt->lock);
return vgpu;
out_clean_sched_policy:
@@ -459,50 +441,12 @@ static struct intel_vgpu *__intel_gvt_create_vgpu(struct intel_gvt *gvt,
intel_vgpu_clean_mmio(vgpu);
out_clean_idr:
idr_remove(&gvt->vgpu_idr, vgpu->id);
-out_free_vgpu:
+out_unlock:
+ mutex_unlock(&gvt->lock);
vfree(vgpu);
return ERR_PTR(ret);
}
-/**
- * intel_gvt_create_vgpu - create a virtual GPU
- * @gvt: GVT device
- * @type: type of the vGPU to create
- *
- * This function is called when user wants to create a virtual GPU.
- *
- * Returns:
- * pointer to intel_vgpu, error pointer if failed.
- */
-struct intel_vgpu *intel_gvt_create_vgpu(struct intel_gvt *gvt,
- struct intel_vgpu_type *type)
-{
- struct intel_vgpu_creation_params param;
- struct intel_vgpu *vgpu;
-
- param.primary = 1;
- param.low_gm_sz = type->low_gm_size;
- param.high_gm_sz = type->high_gm_size;
- param.fence_sz = type->fence;
- param.weight = type->weight;
- param.resolution = type->resolution;
-
- /* XXX current param based on MB */
- param.low_gm_sz = BYTES_TO_MB(param.low_gm_sz);
- param.high_gm_sz = BYTES_TO_MB(param.high_gm_sz);
-
- mutex_lock(&gvt->lock);
- vgpu = __intel_gvt_create_vgpu(gvt, ¶m);
- if (!IS_ERR(vgpu)) {
- /* calculate left instance change for types */
- intel_gvt_update_vgpu_types(gvt);
- intel_gvt_update_reg_whitelist(vgpu);
- }
- mutex_unlock(&gvt->lock);
-
- return vgpu;
-}
-
/**
* intel_gvt_reset_vgpu_locked - reset a virtual GPU by DMLR or GT reset
* @vgpu: virtual GPU
--
2.30.2
^ permalink raw reply related [flat|nested] 31+ messages in thread
* [PATCH 03/15] vfio/mdev: make mdev.h standalone includable
2022-07-06 7:42 simplify the mdev interface v5 Christoph Hellwig
2022-07-06 7:42 ` [PATCH 01/15] drm/i915/gvt: fix a memory leak in intel_gvt_init_vgpu_types Christoph Hellwig
2022-07-06 7:42 ` [PATCH 02/15] drm/i915/gvt: simplify vgpu configuration management Christoph Hellwig
@ 2022-07-06 7:42 ` Christoph Hellwig
2022-07-06 7:42 ` [PATCH 04/15] vfio/mdev: embedd struct mdev_parent in the parent data structure Christoph Hellwig
` (11 subsequent siblings)
14 siblings, 0 replies; 31+ messages in thread
From: Christoph Hellwig @ 2022-07-06 7:42 UTC (permalink / raw)
To: Kirti Wankhede, Tony Krowiak, Halil Pasic, Jason Herne,
Eric Farman, Matthew Rosato, Zhenyu Wang, Zhi Wang,
Alex Williamson
Cc: Jason Gunthorpe, kvm, linux-s390, intel-gvt-dev, Kevin Tian
Include <linux/device.h> and <linux/uuid.h> so that users of this headers
don't need to do that and remove those includes that aren't needed
any more.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed By: Kirti Wankhede <kwankhede@nvidia.com>
---
drivers/gpu/drm/i915/gvt/kvmgt.c | 2 --
drivers/s390/cio/vfio_ccw_drv.c | 2 --
drivers/s390/crypto/vfio_ap_private.h | 1 -
drivers/vfio/mdev/mdev_core.c | 2 --
drivers/vfio/mdev/mdev_driver.c | 1 -
drivers/vfio/mdev/mdev_sysfs.c | 2 --
include/linux/mdev.h | 3 +++
samples/vfio-mdev/mbochs.c | 1 -
samples/vfio-mdev/mdpy.c | 1 -
samples/vfio-mdev/mtty.c | 2 --
10 files changed, 3 insertions(+), 14 deletions(-)
diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
index 7b060c0e66ae7..85e1393d8e55c 100644
--- a/drivers/gpu/drm/i915/gvt/kvmgt.c
+++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
@@ -34,7 +34,6 @@
*/
#include <linux/init.h>
-#include <linux/device.h>
#include <linux/mm.h>
#include <linux/kthread.h>
#include <linux/sched/mm.h>
@@ -43,7 +42,6 @@
#include <linux/rbtree.h>
#include <linux/spinlock.h>
#include <linux/eventfd.h>
-#include <linux/uuid.h>
#include <linux/mdev.h>
#include <linux/debugfs.h>
diff --git a/drivers/s390/cio/vfio_ccw_drv.c b/drivers/s390/cio/vfio_ccw_drv.c
index ee182cfb467d1..750d0315f1f5b 100644
--- a/drivers/s390/cio/vfio_ccw_drv.c
+++ b/drivers/s390/cio/vfio_ccw_drv.c
@@ -12,9 +12,7 @@
#include <linux/module.h>
#include <linux/init.h>
-#include <linux/device.h>
#include <linux/slab.h>
-#include <linux/uuid.h>
#include <linux/mdev.h>
#include <asm/isc.h>
diff --git a/drivers/s390/crypto/vfio_ap_private.h b/drivers/s390/crypto/vfio_ap_private.h
index a26efd804d0df..6616aa83347ad 100644
--- a/drivers/s390/crypto/vfio_ap_private.h
+++ b/drivers/s390/crypto/vfio_ap_private.h
@@ -13,7 +13,6 @@
#define _VFIO_AP_PRIVATE_H_
#include <linux/types.h>
-#include <linux/device.h>
#include <linux/mdev.h>
#include <linux/delay.h>
#include <linux/mutex.h>
diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c
index b8b9e7911e559..2c32923fbad27 100644
--- a/drivers/vfio/mdev/mdev_core.c
+++ b/drivers/vfio/mdev/mdev_core.c
@@ -8,9 +8,7 @@
*/
#include <linux/module.h>
-#include <linux/device.h>
#include <linux/slab.h>
-#include <linux/uuid.h>
#include <linux/sysfs.h>
#include <linux/mdev.h>
diff --git a/drivers/vfio/mdev/mdev_driver.c b/drivers/vfio/mdev/mdev_driver.c
index 9c2af59809e2e..7bd4bb9850e81 100644
--- a/drivers/vfio/mdev/mdev_driver.c
+++ b/drivers/vfio/mdev/mdev_driver.c
@@ -7,7 +7,6 @@
* Kirti Wankhede <kwankhede@nvidia.com>
*/
-#include <linux/device.h>
#include <linux/iommu.h>
#include <linux/mdev.h>
diff --git a/drivers/vfio/mdev/mdev_sysfs.c b/drivers/vfio/mdev/mdev_sysfs.c
index 0ccfeb3dda245..4bfbf49aaa66a 100644
--- a/drivers/vfio/mdev/mdev_sysfs.c
+++ b/drivers/vfio/mdev/mdev_sysfs.c
@@ -9,9 +9,7 @@
#include <linux/sysfs.h>
#include <linux/ctype.h>
-#include <linux/device.h>
#include <linux/slab.h>
-#include <linux/uuid.h>
#include <linux/mdev.h>
#include "mdev_private.h"
diff --git a/include/linux/mdev.h b/include/linux/mdev.h
index bb539794f54a8..555c1d015b5f0 100644
--- a/include/linux/mdev.h
+++ b/include/linux/mdev.h
@@ -10,6 +10,9 @@
#ifndef MDEV_H
#define MDEV_H
+#include <linux/device.h>
+#include <linux/uuid.h>
+
struct mdev_type;
struct mdev_device {
diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c
index 344c2901a82bf..d0d1bb7747240 100644
--- a/samples/vfio-mdev/mbochs.c
+++ b/samples/vfio-mdev/mbochs.c
@@ -21,7 +21,6 @@
*/
#include <linux/init.h>
#include <linux/module.h>
-#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
diff --git a/samples/vfio-mdev/mdpy.c b/samples/vfio-mdev/mdpy.c
index e8c46eb2e2468..0c4ca1f4be7ed 100644
--- a/samples/vfio-mdev/mdpy.c
+++ b/samples/vfio-mdev/mdpy.c
@@ -17,7 +17,6 @@
*/
#include <linux/init.h>
#include <linux/module.h>
-#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
diff --git a/samples/vfio-mdev/mtty.c b/samples/vfio-mdev/mtty.c
index f42a59ed2e3fe..4f5a6f2d3629d 100644
--- a/samples/vfio-mdev/mtty.c
+++ b/samples/vfio-mdev/mtty.c
@@ -12,7 +12,6 @@
#include <linux/init.h>
#include <linux/module.h>
-#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/poll.h>
@@ -20,7 +19,6 @@
#include <linux/cdev.h>
#include <linux/sched.h>
#include <linux/wait.h>
-#include <linux/uuid.h>
#include <linux/vfio.h>
#include <linux/iommu.h>
#include <linux/sysfs.h>
--
2.30.2
^ permalink raw reply related [flat|nested] 31+ messages in thread
* [PATCH 04/15] vfio/mdev: embedd struct mdev_parent in the parent data structure
2022-07-06 7:42 simplify the mdev interface v5 Christoph Hellwig
` (2 preceding siblings ...)
2022-07-06 7:42 ` [PATCH 03/15] vfio/mdev: make mdev.h standalone includable Christoph Hellwig
@ 2022-07-06 7:42 ` Christoph Hellwig
2022-07-06 13:29 ` Kirti Wankhede
2022-07-07 3:08 ` Eric Farman
2022-07-06 7:42 ` [PATCH 05/15] vfio/mdev: simplify mdev_type handling Christoph Hellwig
` (10 subsequent siblings)
14 siblings, 2 replies; 31+ messages in thread
From: Christoph Hellwig @ 2022-07-06 7:42 UTC (permalink / raw)
To: Kirti Wankhede, Tony Krowiak, Halil Pasic, Jason Herne,
Eric Farman, Matthew Rosato, Zhenyu Wang, Zhi Wang,
Alex Williamson
Cc: Jason Gunthorpe, kvm, linux-s390, intel-gvt-dev, Kevin Tian
Simplify mdev_{un}register_device by requiring the caller to pass in
a structure allocate as part of the parent device structure. This
removes the need for a list of parents and the separate mdev_parent
refcount as we can simplify rely on the reference to the parent device.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
---
.../driver-api/vfio-mediated-device.rst | 12 +-
Documentation/s390/vfio-ap.rst | 2 +-
Documentation/s390/vfio-ccw.rst | 2 +-
drivers/gpu/drm/i915/gvt/gvt.h | 2 +
drivers/gpu/drm/i915/gvt/kvmgt.c | 5 +-
drivers/s390/cio/cio.h | 2 +
drivers/s390/cio/vfio_ccw_ops.c | 6 +-
drivers/s390/crypto/vfio_ap_ops.c | 5 +-
drivers/s390/crypto/vfio_ap_private.h | 1 +
drivers/vfio/mdev/mdev_core.c | 120 ++++--------------
drivers/vfio/mdev/mdev_private.h | 23 ----
drivers/vfio/mdev/mdev_sysfs.c | 4 +-
include/linux/mdev.h | 15 ++-
samples/vfio-mdev/mbochs.c | 5 +-
samples/vfio-mdev/mdpy.c | 5 +-
samples/vfio-mdev/mtty.c | 6 +-
16 files changed, 69 insertions(+), 146 deletions(-)
diff --git a/Documentation/driver-api/vfio-mediated-device.rst b/Documentation/driver-api/vfio-mediated-device.rst
index 1c57815619fdf..62a82afce161b 100644
--- a/Documentation/driver-api/vfio-mediated-device.rst
+++ b/Documentation/driver-api/vfio-mediated-device.rst
@@ -60,19 +60,19 @@ devices as examples, as these devices are the first devices to use this module::
| MDEV CORE |
| MODULE |
| mdev.ko |
- | +-----------+ | mdev_register_device() +--------------+
+ | +-----------+ | mdev_register_parent() +--------------+
| | | +<------------------------+ |
| | | | | nvidia.ko |<-> physical
| | | +------------------------>+ | device
| | | | callbacks +--------------+
| | Physical | |
- | | device | | mdev_register_device() +--------------+
+ | | device | | mdev_register_parent() +--------------+
| | interface | |<------------------------+ |
| | | | | i915.ko |<-> physical
| | | +------------------------>+ | device
| | | | callbacks +--------------+
| | | |
- | | | | mdev_register_device() +--------------+
+ | | | | mdev_register_parent() +--------------+
| | | +<------------------------+ |
| | | | | ccw_device.ko|<-> physical
| | | +------------------------>+ | device
@@ -127,8 +127,8 @@ vfio_device_ops.
When a driver wants to add the GUID creation sysfs to an existing device it has
probe'd to then it should call::
- int mdev_register_device(struct device *dev,
- struct mdev_driver *mdev_driver);
+ int mdev_register_parent(struct mdev_parent *parent, struct device *dev,
+ struct mdev_driver *mdev_driver);
This will provide the 'mdev_supported_types/XX/create' files which can then be
used to trigger the creation of a mdev_device. The created mdev_device will be
@@ -136,7 +136,7 @@ attached to the specified driver.
When the driver needs to remove itself it calls::
- void mdev_unregister_device(struct device *dev);
+ void mdev_unregister_parent(struct mdev_parent *parent);
Which will unbind and destroy all the created mdevs and remove the sysfs files.
diff --git a/Documentation/s390/vfio-ap.rst b/Documentation/s390/vfio-ap.rst
index f57ae621f33e8..37e16158c7fbf 100644
--- a/Documentation/s390/vfio-ap.rst
+++ b/Documentation/s390/vfio-ap.rst
@@ -299,7 +299,7 @@ of the VFIO AP mediated matrix device driver::
| MDEV CORE |
| MODULE |
| mdev.ko |
- | +---------+ | mdev_register_device() +--------------+
+ | +---------+ | mdev_register_parent() +--------------+
| |Physical | +<-----------------------+ |
| | device | | | vfio_ap.ko |<-> matrix
| |interface| +----------------------->+ | device
diff --git a/Documentation/s390/vfio-ccw.rst b/Documentation/s390/vfio-ccw.rst
index 8aad08a8b8a50..ea928a3806f43 100644
--- a/Documentation/s390/vfio-ccw.rst
+++ b/Documentation/s390/vfio-ccw.rst
@@ -156,7 +156,7 @@ Below is a high Level block diagram::
| MDEV CORE |
| MODULE |
| mdev.ko |
- | +---------+ | mdev_register_device() +--------------+
+ | +---------+ | mdev_register_parent() +--------------+
| |Physical | +<-----------------------+ |
| | device | | | vfio_ccw.ko |<-> subchannel
| |interface| +----------------------->+ | device
diff --git a/drivers/gpu/drm/i915/gvt/gvt.h b/drivers/gpu/drm/i915/gvt/gvt.h
index 392c2ad49d376..bbf0116671ecb 100644
--- a/drivers/gpu/drm/i915/gvt/gvt.h
+++ b/drivers/gpu/drm/i915/gvt/gvt.h
@@ -36,6 +36,7 @@
#include <uapi/linux/pci_regs.h>
#include <linux/kvm_host.h>
#include <linux/vfio.h>
+#include <linux/mdev.h>
#include "i915_drv.h"
#include "intel_gvt.h"
@@ -338,6 +339,7 @@ struct intel_gvt {
struct intel_gvt_workload_scheduler scheduler;
struct notifier_block shadow_ctx_notifier_block[I915_NUM_ENGINES];
DECLARE_HASHTABLE(cmd_table, GVT_CMD_HASH_BITS);
+ struct mdev_parent parent;
struct intel_vgpu_type *types;
unsigned int num_types;
struct intel_vgpu *idle_vgpu;
diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
index 85e1393d8e55c..e9dba4c0fe6b5 100644
--- a/drivers/gpu/drm/i915/gvt/kvmgt.c
+++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
@@ -1958,7 +1958,7 @@ static void intel_gvt_clean_device(struct drm_i915_private *i915)
if (drm_WARN_ON(&i915->drm, !gvt))
return;
- mdev_unregister_device(i915->drm.dev);
+ mdev_unregister_parent(&gvt->parent);
intel_gvt_cleanup_vgpu_type_groups(gvt);
intel_gvt_destroy_idle_vgpu(gvt->idle_vgpu);
intel_gvt_clean_vgpu_types(gvt);
@@ -2063,7 +2063,8 @@ static int intel_gvt_init_device(struct drm_i915_private *i915)
if (ret)
goto out_destroy_idle_vgpu;
- ret = mdev_register_device(i915->drm.dev, &intel_vgpu_mdev_driver);
+ ret = mdev_register_parent(&gvt->parent, i915->drm.dev,
+ &intel_vgpu_mdev_driver);
if (ret)
goto out_cleanup_vgpu_type_groups;
diff --git a/drivers/s390/cio/cio.h b/drivers/s390/cio/cio.h
index fa8df50bb49e3..22be5ac7d23c1 100644
--- a/drivers/s390/cio/cio.h
+++ b/drivers/s390/cio/cio.h
@@ -5,6 +5,7 @@
#include <linux/mutex.h>
#include <linux/device.h>
#include <linux/mod_devicetable.h>
+#include <linux/mdev.h>
#include <asm/chpid.h>
#include <asm/cio.h>
#include <asm/fcx.h>
@@ -108,6 +109,7 @@ struct subchannel {
* frees it. Use driver_set_override() to set or clear it.
*/
const char *driver_override;
+ struct mdev_parent parent;
} __attribute__ ((aligned(8)));
DECLARE_PER_CPU_ALIGNED(struct irb, cio_irb);
diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c
index b49e2e9db2dc6..9192a21085ce4 100644
--- a/drivers/s390/cio/vfio_ccw_ops.c
+++ b/drivers/s390/cio/vfio_ccw_ops.c
@@ -11,7 +11,6 @@
*/
#include <linux/vfio.h>
-#include <linux/mdev.h>
#include <linux/nospec.h>
#include <linux/slab.h>
@@ -660,10 +659,11 @@ struct mdev_driver vfio_ccw_mdev_driver = {
int vfio_ccw_mdev_reg(struct subchannel *sch)
{
- return mdev_register_device(&sch->dev, &vfio_ccw_mdev_driver);
+ return mdev_register_parent(&sch->parent, &sch->dev,
+ &vfio_ccw_mdev_driver);
}
void vfio_ccw_mdev_unreg(struct subchannel *sch)
{
- mdev_unregister_device(&sch->dev);
+ mdev_unregister_parent(&sch->parent);
}
diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
index a7d2a95796d36..834945150dc9f 100644
--- a/drivers/s390/crypto/vfio_ap_ops.c
+++ b/drivers/s390/crypto/vfio_ap_ops.c
@@ -1485,7 +1485,8 @@ int vfio_ap_mdev_register(void)
if (ret)
return ret;
- ret = mdev_register_device(&matrix_dev->device, &vfio_ap_matrix_driver);
+ ret = mdev_register_parent(&matrix_dev->parent, &matrix_dev->device,
+ &vfio_ap_matrix_driver);
if (ret)
goto err_driver;
return 0;
@@ -1497,6 +1498,6 @@ int vfio_ap_mdev_register(void)
void vfio_ap_mdev_unregister(void)
{
- mdev_unregister_device(&matrix_dev->device);
+ mdev_unregister_parent(&matrix_dev->parent);
mdev_unregister_driver(&vfio_ap_matrix_driver);
}
diff --git a/drivers/s390/crypto/vfio_ap_private.h b/drivers/s390/crypto/vfio_ap_private.h
index 6616aa83347ad..0191f6bc973a4 100644
--- a/drivers/s390/crypto/vfio_ap_private.h
+++ b/drivers/s390/crypto/vfio_ap_private.h
@@ -45,6 +45,7 @@ struct ap_matrix_dev {
struct list_head mdev_list;
struct mutex lock;
struct ap_driver *vfio_ap_drv;
+ struct mdev_parent parent;
};
extern struct ap_matrix_dev *matrix_dev;
diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c
index 2c32923fbad27..fa05ac3396950 100644
--- a/drivers/vfio/mdev/mdev_core.c
+++ b/drivers/vfio/mdev/mdev_core.c
@@ -18,8 +18,6 @@
#define DRIVER_AUTHOR "NVIDIA Corporation"
#define DRIVER_DESC "Mediated device Core Driver"
-static LIST_HEAD(parent_list);
-static DEFINE_MUTEX(parent_list_lock);
static struct class_compat *mdev_bus_compat_class;
static LIST_HEAD(mdev_list);
@@ -61,28 +59,6 @@ struct device *mtype_get_parent_dev(struct mdev_type *mtype)
}
EXPORT_SYMBOL(mtype_get_parent_dev);
-/* Should be called holding parent_list_lock */
-static struct mdev_parent *__find_parent_device(struct device *dev)
-{
- struct mdev_parent *parent;
-
- list_for_each_entry(parent, &parent_list, next) {
- if (parent->dev == dev)
- return parent;
- }
- return NULL;
-}
-
-void mdev_release_parent(struct kref *kref)
-{
- struct mdev_parent *parent = container_of(kref, struct mdev_parent,
- ref);
- struct device *dev = parent->dev;
-
- kfree(parent);
- put_device(dev);
-}
-
/* Caller must hold parent unreg_sem read or write lock */
static void mdev_device_remove_common(struct mdev_device *mdev)
{
@@ -105,125 +81,73 @@ static int mdev_device_remove_cb(struct device *dev, void *data)
}
/*
- * mdev_register_device : Register a device
+ * mdev_register_parent: Register a device as parent for mdevs
+ * @parent: parent structure registered
* @dev: device structure representing parent device.
* @mdev_driver: Device driver to bind to the newly created mdev
*
- * Add device to list of registered parent devices.
+ * Registers the @parent stucture as a parent for mdev types and thus mdev
+ * devices. The caller needs to hold a reference on @dev that must not be
+ * released until after the call to mdev_unregister_parent().
+ *
* Returns a negative value on error, otherwise 0.
*/
-int mdev_register_device(struct device *dev, struct mdev_driver *mdev_driver)
+int mdev_register_parent(struct mdev_parent *parent, struct device *dev,
+ struct mdev_driver *mdev_driver)
{
- int ret;
- struct mdev_parent *parent;
char *env_string = "MDEV_STATE=registered";
char *envp[] = { env_string, NULL };
+ int ret;
/* check for mandatory ops */
if (!mdev_driver->supported_type_groups)
return -EINVAL;
- dev = get_device(dev);
- if (!dev)
- return -EINVAL;
-
- mutex_lock(&parent_list_lock);
-
- /* Check for duplicate */
- parent = __find_parent_device(dev);
- if (parent) {
- parent = NULL;
- ret = -EEXIST;
- goto add_dev_err;
- }
-
- parent = kzalloc(sizeof(*parent), GFP_KERNEL);
- if (!parent) {
- ret = -ENOMEM;
- goto add_dev_err;
- }
-
- kref_init(&parent->ref);
+ memset(parent, 0, sizeof(*parent));
init_rwsem(&parent->unreg_sem);
-
parent->dev = dev;
parent->mdev_driver = mdev_driver;
if (!mdev_bus_compat_class) {
mdev_bus_compat_class = class_compat_register("mdev_bus");
- if (!mdev_bus_compat_class) {
- ret = -ENOMEM;
- goto add_dev_err;
- }
+ if (!mdev_bus_compat_class)
+ return -ENOMEM;
}
ret = parent_create_sysfs_files(parent);
if (ret)
- goto add_dev_err;
+ return ret;
ret = class_compat_create_link(mdev_bus_compat_class, dev, NULL);
if (ret)
dev_warn(dev, "Failed to create compatibility class link\n");
- list_add(&parent->next, &parent_list);
- mutex_unlock(&parent_list_lock);
-
dev_info(dev, "MDEV: Registered\n");
kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
-
return 0;
-
-add_dev_err:
- mutex_unlock(&parent_list_lock);
- if (parent)
- mdev_put_parent(parent);
- else
- put_device(dev);
- return ret;
}
-EXPORT_SYMBOL(mdev_register_device);
+EXPORT_SYMBOL(mdev_register_parent);
/*
- * mdev_unregister_device : Unregister a parent device
- * @dev: device structure representing parent device.
- *
- * Remove device from list of registered parent devices. Give a chance to free
- * existing mediated devices for given device.
+ * mdev_unregister_parent : Unregister a parent device
+ * @parent: parent structure to unregister
*/
-
-void mdev_unregister_device(struct device *dev)
+void mdev_unregister_parent(struct mdev_parent *parent)
{
- struct mdev_parent *parent;
char *env_string = "MDEV_STATE=unregistered";
char *envp[] = { env_string, NULL };
- mutex_lock(&parent_list_lock);
- parent = __find_parent_device(dev);
-
- if (!parent) {
- mutex_unlock(&parent_list_lock);
- return;
- }
- dev_info(dev, "MDEV: Unregistering\n");
-
- list_del(&parent->next);
- mutex_unlock(&parent_list_lock);
+ dev_info(parent->dev, "MDEV: Unregistering\n");
down_write(&parent->unreg_sem);
-
- class_compat_remove_link(mdev_bus_compat_class, dev, NULL);
-
- device_for_each_child(dev, NULL, mdev_device_remove_cb);
-
+ class_compat_remove_link(mdev_bus_compat_class, parent->dev, NULL);
+ device_for_each_child(parent->dev, NULL, mdev_device_remove_cb);
parent_remove_sysfs_files(parent);
up_write(&parent->unreg_sem);
- mdev_put_parent(parent);
-
- /* We still have the caller's reference to use for the uevent */
- kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
+ kobject_uevent_env(&parent->dev->kobj, KOBJ_CHANGE, envp);
}
-EXPORT_SYMBOL(mdev_unregister_device);
+EXPORT_SYMBOL(mdev_unregister_parent);
static void mdev_device_release(struct device *dev)
{
diff --git a/drivers/vfio/mdev/mdev_private.h b/drivers/vfio/mdev/mdev_private.h
index 7c9fc79f3d838..297f911fdc890 100644
--- a/drivers/vfio/mdev/mdev_private.h
+++ b/drivers/vfio/mdev/mdev_private.h
@@ -13,17 +13,6 @@
int mdev_bus_register(void);
void mdev_bus_unregister(void);
-struct mdev_parent {
- struct device *dev;
- struct mdev_driver *mdev_driver;
- struct kref ref;
- struct list_head next;
- struct kset *mdev_types_kset;
- struct list_head type_list;
- /* Synchronize device creation/removal with parent unregistration */
- struct rw_semaphore unreg_sem;
-};
-
struct mdev_type {
struct kobject kobj;
struct kobject *devices_kobj;
@@ -48,16 +37,4 @@ void mdev_remove_sysfs_files(struct mdev_device *mdev);
int mdev_device_create(struct mdev_type *kobj, const guid_t *uuid);
int mdev_device_remove(struct mdev_device *dev);
-void mdev_release_parent(struct kref *kref);
-
-static inline void mdev_get_parent(struct mdev_parent *parent)
-{
- kref_get(&parent->ref);
-}
-
-static inline void mdev_put_parent(struct mdev_parent *parent)
-{
- kref_put(&parent->ref, mdev_release_parent);
-}
-
#endif /* MDEV_PRIVATE_H */
diff --git a/drivers/vfio/mdev/mdev_sysfs.c b/drivers/vfio/mdev/mdev_sysfs.c
index 4bfbf49aaa66a..b71ffc5594870 100644
--- a/drivers/vfio/mdev/mdev_sysfs.c
+++ b/drivers/vfio/mdev/mdev_sysfs.c
@@ -81,7 +81,7 @@ static void mdev_type_release(struct kobject *kobj)
pr_debug("Releasing group %s\n", kobj->name);
/* Pairs with the get in add_mdev_supported_type() */
- mdev_put_parent(type->parent);
+ put_device(type->parent->dev);
kfree(type);
}
@@ -110,7 +110,7 @@ static struct mdev_type *add_mdev_supported_type(struct mdev_parent *parent,
type->kobj.kset = parent->mdev_types_kset;
type->parent = parent;
/* Pairs with the put in mdev_type_release() */
- mdev_get_parent(parent);
+ get_device(parent->dev);
type->type_group_id = type_group_id;
ret = kobject_init_and_add(&type->kobj, &mdev_type_ktype, NULL,
diff --git a/include/linux/mdev.h b/include/linux/mdev.h
index 555c1d015b5f0..327ce3e5c6b5f 100644
--- a/include/linux/mdev.h
+++ b/include/linux/mdev.h
@@ -23,6 +23,16 @@ struct mdev_device {
bool active;
};
+/* embedded into the struct device that the mdev devices hang off */
+struct mdev_parent {
+ struct device *dev;
+ struct mdev_driver *mdev_driver;
+ struct kset *mdev_types_kset;
+ struct list_head type_list;
+ /* Synchronize device creation/removal with parent unregistration */
+ struct rw_semaphore unreg_sem;
+};
+
static inline struct mdev_device *to_mdev_device(struct device *dev)
{
return container_of(dev, struct mdev_device, dev);
@@ -75,8 +85,9 @@ static inline const guid_t *mdev_uuid(struct mdev_device *mdev)
extern struct bus_type mdev_bus_type;
-int mdev_register_device(struct device *dev, struct mdev_driver *mdev_driver);
-void mdev_unregister_device(struct device *dev);
+int mdev_register_parent(struct mdev_parent *parent, struct device *dev,
+ struct mdev_driver *mdev_driver);
+void mdev_unregister_parent(struct mdev_parent *parent);
int mdev_register_driver(struct mdev_driver *drv);
void mdev_unregister_driver(struct mdev_driver *drv);
diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c
index d0d1bb7747240..30b3643b3b389 100644
--- a/samples/vfio-mdev/mbochs.c
+++ b/samples/vfio-mdev/mbochs.c
@@ -128,6 +128,7 @@ static dev_t mbochs_devt;
static struct class *mbochs_class;
static struct cdev mbochs_cdev;
static struct device mbochs_dev;
+static struct mdev_parent mbochs_parent;
static atomic_t mbochs_avail_mbytes;
static const struct vfio_device_ops mbochs_dev_ops;
@@ -1456,7 +1457,7 @@ static int __init mbochs_dev_init(void)
if (ret)
goto err_class;
- ret = mdev_register_device(&mbochs_dev, &mbochs_driver);
+ ret = mdev_register_parent(&mbochs_parent, &mbochs_dev, &mbochs_driver);
if (ret)
goto err_device;
@@ -1477,7 +1478,7 @@ static int __init mbochs_dev_init(void)
static void __exit mbochs_dev_exit(void)
{
mbochs_dev.bus = NULL;
- mdev_unregister_device(&mbochs_dev);
+ mdev_unregister_parent(&mbochs_parent);
device_unregister(&mbochs_dev);
mdev_unregister_driver(&mbochs_driver);
diff --git a/samples/vfio-mdev/mdpy.c b/samples/vfio-mdev/mdpy.c
index 0c4ca1f4be7ed..132bb055628a6 100644
--- a/samples/vfio-mdev/mdpy.c
+++ b/samples/vfio-mdev/mdpy.c
@@ -83,6 +83,7 @@ static dev_t mdpy_devt;
static struct class *mdpy_class;
static struct cdev mdpy_cdev;
static struct device mdpy_dev;
+static struct mdev_parent mdpy_parent;
static u32 mdpy_count;
static const struct vfio_device_ops mdpy_dev_ops;
@@ -765,7 +766,7 @@ static int __init mdpy_dev_init(void)
if (ret)
goto err_class;
- ret = mdev_register_device(&mdpy_dev, &mdpy_driver);
+ ret = mdev_register_parent(&mdpy_parent, &mdpy_dev, &mdpy_driver);
if (ret)
goto err_device;
@@ -786,7 +787,7 @@ static int __init mdpy_dev_init(void)
static void __exit mdpy_dev_exit(void)
{
mdpy_dev.bus = NULL;
- mdev_unregister_device(&mdpy_dev);
+ mdev_unregister_parent(&mdpy_parent);
device_unregister(&mdpy_dev);
mdev_unregister_driver(&mdpy_driver);
diff --git a/samples/vfio-mdev/mtty.c b/samples/vfio-mdev/mtty.c
index 4f5a6f2d3629d..8ba5f6084a093 100644
--- a/samples/vfio-mdev/mtty.c
+++ b/samples/vfio-mdev/mtty.c
@@ -72,6 +72,7 @@ static struct mtty_dev {
struct cdev vd_cdev;
struct idr vd_idr;
struct device dev;
+ struct mdev_parent parent;
} mtty_dev;
struct mdev_region_info {
@@ -1350,7 +1351,8 @@ static int __init mtty_dev_init(void)
if (ret)
goto err_class;
- ret = mdev_register_device(&mtty_dev.dev, &mtty_driver);
+ ret = mdev_register_parent(&mtty_dev.parent, &mtty_dev.dev,
+ &mtty_driver);
if (ret)
goto err_device;
return 0;
@@ -1370,7 +1372,7 @@ static int __init mtty_dev_init(void)
static void __exit mtty_dev_exit(void)
{
mtty_dev.dev.bus = NULL;
- mdev_unregister_device(&mtty_dev.dev);
+ mdev_unregister_parent(&mtty_dev.parent);
device_unregister(&mtty_dev.dev);
idr_destroy(&mtty_dev.vd_idr);
--
2.30.2
^ permalink raw reply related [flat|nested] 31+ messages in thread
* [PATCH 05/15] vfio/mdev: simplify mdev_type handling
2022-07-06 7:42 simplify the mdev interface v5 Christoph Hellwig
` (3 preceding siblings ...)
2022-07-06 7:42 ` [PATCH 04/15] vfio/mdev: embedd struct mdev_parent in the parent data structure Christoph Hellwig
@ 2022-07-06 7:42 ` Christoph Hellwig
2022-07-06 13:31 ` Kirti Wankhede
2022-07-06 7:42 ` [PATCH 06/15] vfio/mdev: remove mdev_from_dev Christoph Hellwig
` (9 subsequent siblings)
14 siblings, 1 reply; 31+ messages in thread
From: Christoph Hellwig @ 2022-07-06 7:42 UTC (permalink / raw)
To: Kirti Wankhede, Tony Krowiak, Halil Pasic, Jason Herne,
Eric Farman, Matthew Rosato, Zhenyu Wang, Zhi Wang,
Alex Williamson
Cc: Jason Gunthorpe, kvm, linux-s390, intel-gvt-dev, Kevin Tian
Instead of abusing struct attribute_group to control initialization of
struct mdev_type, just define the actual attributes in the mdev_driver,
allocate the mdev_type structures in the caller and pass them to
mdev_register_parent.
This allows the caller to use container_of to get at the containing
structure and thus significantly simplify the code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
---
.../driver-api/vfio-mediated-device.rst | 2 +-
drivers/gpu/drm/i915/gvt/gvt.h | 3 +-
drivers/gpu/drm/i915/gvt/kvmgt.c | 98 +++----------------
drivers/gpu/drm/i915/gvt/vgpu.c | 13 ++-
drivers/s390/cio/cio.h | 2 +
drivers/s390/cio/vfio_ccw_ops.c | 19 ++--
drivers/s390/crypto/vfio_ap_ops.c | 19 ++--
drivers/s390/crypto/vfio_ap_private.h | 2 +
drivers/vfio/mdev/mdev_core.c | 31 ++----
drivers/vfio/mdev/mdev_driver.c | 5 +-
drivers/vfio/mdev/mdev_private.h | 8 --
drivers/vfio/mdev/mdev_sysfs.c | 90 +++++------------
include/linux/mdev.h | 26 +++--
samples/vfio-mdev/mbochs.c | 57 +++++------
samples/vfio-mdev/mdpy.c | 50 ++++------
samples/vfio-mdev/mtty.c | 62 ++++++------
16 files changed, 165 insertions(+), 322 deletions(-)
diff --git a/Documentation/driver-api/vfio-mediated-device.rst b/Documentation/driver-api/vfio-mediated-device.rst
index 62a82afce161b..82a4007bd7207 100644
--- a/Documentation/driver-api/vfio-mediated-device.rst
+++ b/Documentation/driver-api/vfio-mediated-device.rst
@@ -105,7 +105,7 @@ structure to represent a mediated device's driver::
struct mdev_driver {
int (*probe) (struct mdev_device *dev);
void (*remove) (struct mdev_device *dev);
- struct attribute_group **supported_type_groups;
+ const struct attribute * const *types_attrs;
struct device_driver driver;
};
diff --git a/drivers/gpu/drm/i915/gvt/gvt.h b/drivers/gpu/drm/i915/gvt/gvt.h
index bbf0116671ecb..f9690dca0a857 100644
--- a/drivers/gpu/drm/i915/gvt/gvt.h
+++ b/drivers/gpu/drm/i915/gvt/gvt.h
@@ -311,8 +311,8 @@ struct intel_vgpu_config {
const char *name;
};
-#define NR_MAX_INTEL_VGPU_TYPES 20
struct intel_vgpu_type {
+ struct mdev_type type;
char name[16];
const struct intel_vgpu_config *conf;
unsigned int avail_instance;
@@ -340,6 +340,7 @@ struct intel_gvt {
struct notifier_block shadow_ctx_notifier_block[I915_NUM_ENGINES];
DECLARE_HASHTABLE(cmd_table, GVT_CMD_HASH_BITS);
struct mdev_parent parent;
+ struct mdev_type **mdev_types;
struct intel_vgpu_type *types;
unsigned int num_types;
struct intel_vgpu *idle_vgpu;
diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
index e9dba4c0fe6b5..ead56e4d30650 100644
--- a/drivers/gpu/drm/i915/gvt/kvmgt.c
+++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
@@ -117,17 +117,10 @@ static ssize_t available_instances_show(struct mdev_type *mtype,
struct mdev_type_attribute *attr,
char *buf)
{
- struct intel_vgpu_type *type;
- unsigned int num = 0;
- struct intel_gvt *gvt = kdev_to_i915(mtype_get_parent_dev(mtype))->gvt;
+ struct intel_vgpu_type *type =
+ container_of(mtype, struct intel_vgpu_type, type);
- type = &gvt->types[mtype_get_type_group_id(mtype)];
- if (!type)
- num = 0;
- else
- num = type->avail_instance;
-
- return sprintf(buf, "%u\n", num);
+ return sprintf(buf, "%u\n", type->avail_instance);
}
static ssize_t device_api_show(struct mdev_type *mtype,
@@ -139,12 +132,8 @@ static ssize_t device_api_show(struct mdev_type *mtype,
static ssize_t description_show(struct mdev_type *mtype,
struct mdev_type_attribute *attr, char *buf)
{
- struct intel_vgpu_type *type;
- struct intel_gvt *gvt = kdev_to_i915(mtype_get_parent_dev(mtype))->gvt;
-
- type = &gvt->types[mtype_get_type_group_id(mtype)];
- if (!type)
- return 0;
+ struct intel_vgpu_type *type =
+ container_of(mtype, struct intel_vgpu_type, type);
return sprintf(buf, "low_gm_size: %dMB\nhigh_gm_size: %dMB\n"
"fence: %d\nresolution: %s\n"
@@ -158,14 +147,7 @@ static ssize_t description_show(struct mdev_type *mtype,
static ssize_t name_show(struct mdev_type *mtype,
struct mdev_type_attribute *attr, char *buf)
{
- struct intel_vgpu_type *type;
- struct intel_gvt *gvt = kdev_to_i915(mtype_get_parent_dev(mtype))->gvt;
-
- type = &gvt->types[mtype_get_type_group_id(mtype)];
- if (!type)
- return 0;
-
- return sprintf(buf, "%s\n", type->name);
+ return sprintf(buf, "%s\n", mtype->sysfs_name);
}
static MDEV_TYPE_ATTR_RO(available_instances);
@@ -173,7 +155,7 @@ static MDEV_TYPE_ATTR_RO(device_api);
static MDEV_TYPE_ATTR_RO(description);
static MDEV_TYPE_ATTR_RO(name);
-static struct attribute *gvt_type_attrs[] = {
+static const struct attribute *gvt_type_attrs[] = {
&mdev_type_attr_available_instances.attr,
&mdev_type_attr_device_api.attr,
&mdev_type_attr_description.attr,
@@ -181,51 +163,6 @@ static struct attribute *gvt_type_attrs[] = {
NULL,
};
-static struct attribute_group *gvt_vgpu_type_groups[] = {
- [0 ... NR_MAX_INTEL_VGPU_TYPES - 1] = NULL,
-};
-
-static int intel_gvt_init_vgpu_type_groups(struct intel_gvt *gvt)
-{
- int i, j;
- struct intel_vgpu_type *type;
- struct attribute_group *group;
-
- for (i = 0; i < gvt->num_types; i++) {
- type = &gvt->types[i];
-
- group = kzalloc(sizeof(struct attribute_group), GFP_KERNEL);
- if (!group)
- goto unwind;
-
- group->name = type->name;
- group->attrs = gvt_type_attrs;
- gvt_vgpu_type_groups[i] = group;
- }
-
- return 0;
-
-unwind:
- for (j = 0; j < i; j++) {
- group = gvt_vgpu_type_groups[j];
- kfree(group);
- }
-
- return -ENOMEM;
-}
-
-static void intel_gvt_cleanup_vgpu_type_groups(struct intel_gvt *gvt)
-{
- int i;
- struct attribute_group *group;
-
- for (i = 0; i < gvt->num_types; i++) {
- group = gvt_vgpu_type_groups[i];
- gvt_vgpu_type_groups[i] = NULL;
- kfree(group);
- }
-}
-
static void gvt_unpin_guest_page(struct intel_vgpu *vgpu, unsigned long gfn,
unsigned long size)
{
@@ -1614,14 +1551,11 @@ static int intel_vgpu_probe(struct mdev_device *mdev)
{
struct device *pdev = mdev_parent_dev(mdev);
struct intel_gvt *gvt = kdev_to_i915(pdev)->gvt;
- struct intel_vgpu_type *type;
+ struct intel_vgpu_type *type =
+ container_of(mdev->type, struct intel_vgpu_type, type);
struct intel_vgpu *vgpu;
int ret;
- type = &gvt->types[mdev_get_type_group_id(mdev)];
- if (!type)
- return -EINVAL;
-
vgpu = intel_gvt_create_vgpu(gvt, type->conf);
if (IS_ERR(vgpu)) {
gvt_err("failed to create intel vgpu: %ld\n", PTR_ERR(vgpu));
@@ -1660,7 +1594,7 @@ static struct mdev_driver intel_vgpu_mdev_driver = {
},
.probe = intel_vgpu_probe,
.remove = intel_vgpu_remove,
- .supported_type_groups = gvt_vgpu_type_groups,
+ .types_attrs = gvt_type_attrs,
};
int intel_gvt_page_track_add(struct intel_vgpu *info, u64 gfn)
@@ -1959,7 +1893,6 @@ static void intel_gvt_clean_device(struct drm_i915_private *i915)
return;
mdev_unregister_parent(&gvt->parent);
- intel_gvt_cleanup_vgpu_type_groups(gvt);
intel_gvt_destroy_idle_vgpu(gvt->idle_vgpu);
intel_gvt_clean_vgpu_types(gvt);
@@ -2059,20 +1992,15 @@ static int intel_gvt_init_device(struct drm_i915_private *i915)
intel_gvt_debugfs_init(gvt);
- ret = intel_gvt_init_vgpu_type_groups(gvt);
- if (ret)
- goto out_destroy_idle_vgpu;
-
ret = mdev_register_parent(&gvt->parent, i915->drm.dev,
- &intel_vgpu_mdev_driver);
+ &intel_vgpu_mdev_driver,
+ gvt->mdev_types, gvt->num_types);
if (ret)
- goto out_cleanup_vgpu_type_groups;
+ goto out_destroy_idle_vgpu;
gvt_dbg_core("gvt device initialization is done\n");
return 0;
-out_cleanup_vgpu_type_groups:
- intel_gvt_cleanup_vgpu_type_groups(gvt);
out_destroy_idle_vgpu:
intel_gvt_destroy_idle_vgpu(gvt->idle_vgpu);
intel_gvt_debugfs_clean(gvt);
diff --git a/drivers/gpu/drm/i915/gvt/vgpu.c b/drivers/gpu/drm/i915/gvt/vgpu.c
index 8e136dcc70112..ff240503d4125 100644
--- a/drivers/gpu/drm/i915/gvt/vgpu.c
+++ b/drivers/gpu/drm/i915/gvt/vgpu.c
@@ -113,13 +113,18 @@ int intel_gvt_init_vgpu_types(struct intel_gvt *gvt)
if (!gvt->types)
return -ENOMEM;
+ gvt->mdev_types = kcalloc(num_types, sizeof(*gvt->mdev_types),
+ GFP_KERNEL);
+ if (!gvt->mdev_types)
+ goto out_free_types;
+
for (i = 0; i < num_types; ++i) {
const struct intel_vgpu_config *conf = &intel_vgpu_configs[i];
if (low_avail / conf->low_mm == 0)
break;
if (conf->weight < 1 || conf->weight > VGPU_MAX_WEIGHT)
- goto out_free_types;
+ goto out_free_mdev_types;
sprintf(gvt->types[i].name, "GVTg_V%u_%s",
GRAPHICS_VER(gvt->gt->i915) == 8 ? 4 : 5, conf->name);
@@ -131,11 +136,16 @@ int intel_gvt_init_vgpu_types(struct intel_gvt *gvt)
i, gvt->types[i].name, gvt->types[i].avail_instance,
conf->low_mm, conf->high_mm, conf->fence,
conf->weight, vgpu_edid_str(conf->edid));
+
+ gvt->mdev_types[i] = &gvt->types[i].type;
+ gvt->mdev_types[i]->sysfs_name = gvt->types[i].name;
}
gvt->num_types = i;
return 0;
+out_free_mdev_types:
+ kfree(gvt->mdev_types);
out_free_types:
kfree(gvt->types);
return -EINVAL;
@@ -143,6 +153,7 @@ int intel_gvt_init_vgpu_types(struct intel_gvt *gvt)
void intel_gvt_clean_vgpu_types(struct intel_gvt *gvt)
{
+ kfree(gvt->mdev_types);
kfree(gvt->types);
}
diff --git a/drivers/s390/cio/cio.h b/drivers/s390/cio/cio.h
index 22be5ac7d23c1..1da45307a1862 100644
--- a/drivers/s390/cio/cio.h
+++ b/drivers/s390/cio/cio.h
@@ -110,6 +110,8 @@ struct subchannel {
*/
const char *driver_override;
struct mdev_parent parent;
+ struct mdev_type mdev_type;
+ struct mdev_type *mdev_types[1];
} __attribute__ ((aligned(8)));
DECLARE_PER_CPU_ALIGNED(struct irb, cio_irb);
diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c
index 9192a21085ce4..1bb30313a630c 100644
--- a/drivers/s390/cio/vfio_ccw_ops.c
+++ b/drivers/s390/cio/vfio_ccw_ops.c
@@ -95,23 +95,13 @@ static ssize_t available_instances_show(struct mdev_type *mtype,
}
static MDEV_TYPE_ATTR_RO(available_instances);
-static struct attribute *mdev_types_attrs[] = {
+static const struct attribute *mdev_types_attrs[] = {
&mdev_type_attr_name.attr,
&mdev_type_attr_device_api.attr,
&mdev_type_attr_available_instances.attr,
NULL,
};
-static struct attribute_group mdev_type_group = {
- .name = "io",
- .attrs = mdev_types_attrs,
-};
-
-static struct attribute_group *mdev_type_groups[] = {
- &mdev_type_group,
- NULL,
-};
-
static int vfio_ccw_mdev_probe(struct mdev_device *mdev)
{
struct vfio_ccw_private *private = dev_get_drvdata(mdev->dev.parent);
@@ -654,13 +644,16 @@ struct mdev_driver vfio_ccw_mdev_driver = {
},
.probe = vfio_ccw_mdev_probe,
.remove = vfio_ccw_mdev_remove,
- .supported_type_groups = mdev_type_groups,
+ .types_attrs = mdev_types_attrs,
};
int vfio_ccw_mdev_reg(struct subchannel *sch)
{
+ sch->mdev_type.sysfs_name = "io";
+ sch->mdev_types[0] = &sch->mdev_type;
return mdev_register_parent(&sch->parent, &sch->dev,
- &vfio_ccw_mdev_driver);
+ &vfio_ccw_mdev_driver, sch->mdev_types,
+ 1);
}
void vfio_ccw_mdev_unreg(struct subchannel *sch)
diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
index 834945150dc9f..41e8ecb7f56b9 100644
--- a/drivers/s390/crypto/vfio_ap_ops.c
+++ b/drivers/s390/crypto/vfio_ap_ops.c
@@ -537,23 +537,13 @@ static ssize_t device_api_show(struct mdev_type *mtype,
static MDEV_TYPE_ATTR_RO(device_api);
-static struct attribute *vfio_ap_mdev_type_attrs[] = {
+static const struct attribute *vfio_ap_mdev_type_attrs[] = {
&mdev_type_attr_name.attr,
&mdev_type_attr_device_api.attr,
&mdev_type_attr_available_instances.attr,
NULL,
};
-static struct attribute_group vfio_ap_mdev_hwvirt_type_group = {
- .name = VFIO_AP_MDEV_TYPE_HWVIRT,
- .attrs = vfio_ap_mdev_type_attrs,
-};
-
-static struct attribute_group *vfio_ap_mdev_type_groups[] = {
- &vfio_ap_mdev_hwvirt_type_group,
- NULL,
-};
-
struct vfio_ap_queue_reserved {
unsigned long *apid;
unsigned long *apqi;
@@ -1472,7 +1462,7 @@ static struct mdev_driver vfio_ap_matrix_driver = {
},
.probe = vfio_ap_mdev_probe,
.remove = vfio_ap_mdev_remove,
- .supported_type_groups = vfio_ap_mdev_type_groups,
+ .types_attrs = vfio_ap_mdev_type_attrs,
};
int vfio_ap_mdev_register(void)
@@ -1485,8 +1475,11 @@ int vfio_ap_mdev_register(void)
if (ret)
return ret;
+ matrix_dev->mdev_type.sysfs_name = VFIO_AP_MDEV_TYPE_HWVIRT;
+ matrix_dev->mdev_types[0] = &matrix_dev->mdev_type;
ret = mdev_register_parent(&matrix_dev->parent, &matrix_dev->device,
- &vfio_ap_matrix_driver);
+ &vfio_ap_matrix_driver,
+ matrix_dev->mdev_types, 1);
if (ret)
goto err_driver;
return 0;
diff --git a/drivers/s390/crypto/vfio_ap_private.h b/drivers/s390/crypto/vfio_ap_private.h
index 0191f6bc973a4..5dc5050d03791 100644
--- a/drivers/s390/crypto/vfio_ap_private.h
+++ b/drivers/s390/crypto/vfio_ap_private.h
@@ -46,6 +46,8 @@ struct ap_matrix_dev {
struct mutex lock;
struct ap_driver *vfio_ap_drv;
struct mdev_parent parent;
+ struct mdev_type mdev_type;
+ struct mdev_type *mdev_types[];
};
extern struct ap_matrix_dev *matrix_dev;
diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c
index fa05ac3396950..2d95a497fd3b2 100644
--- a/drivers/vfio/mdev/mdev_core.c
+++ b/drivers/vfio/mdev/mdev_core.c
@@ -29,26 +29,6 @@ struct device *mdev_parent_dev(struct mdev_device *mdev)
}
EXPORT_SYMBOL(mdev_parent_dev);
-/*
- * Return the index in supported_type_groups that this mdev_device was created
- * from.
- */
-unsigned int mdev_get_type_group_id(struct mdev_device *mdev)
-{
- return mdev->type->type_group_id;
-}
-EXPORT_SYMBOL(mdev_get_type_group_id);
-
-/*
- * Used in mdev_type_attribute sysfs functions to return the index in the
- * supported_type_groups that the sysfs is called from.
- */
-unsigned int mtype_get_type_group_id(struct mdev_type *mtype)
-{
- return mtype->type_group_id;
-}
-EXPORT_SYMBOL(mtype_get_type_group_id);
-
/*
* Used in mdev_type_attribute sysfs functions to return the parent struct
* device
@@ -85,6 +65,8 @@ static int mdev_device_remove_cb(struct device *dev, void *data)
* @parent: parent structure registered
* @dev: device structure representing parent device.
* @mdev_driver: Device driver to bind to the newly created mdev
+ * @types: Array of supported mdev types
+ * @nr_types: Number of entries in @types
*
* Registers the @parent stucture as a parent for mdev types and thus mdev
* devices. The caller needs to hold a reference on @dev that must not be
@@ -93,20 +75,19 @@ static int mdev_device_remove_cb(struct device *dev, void *data)
* Returns a negative value on error, otherwise 0.
*/
int mdev_register_parent(struct mdev_parent *parent, struct device *dev,
- struct mdev_driver *mdev_driver)
+ struct mdev_driver *mdev_driver, struct mdev_type **types,
+ unsigned int nr_types)
{
char *env_string = "MDEV_STATE=registered";
char *envp[] = { env_string, NULL };
int ret;
- /* check for mandatory ops */
- if (!mdev_driver->supported_type_groups)
- return -EINVAL;
-
memset(parent, 0, sizeof(*parent));
init_rwsem(&parent->unreg_sem);
parent->dev = dev;
parent->mdev_driver = mdev_driver;
+ parent->types = types;
+ parent->nr_types = nr_types;
if (!mdev_bus_compat_class) {
mdev_bus_compat_class = class_compat_register("mdev_bus");
diff --git a/drivers/vfio/mdev/mdev_driver.c b/drivers/vfio/mdev/mdev_driver.c
index 7bd4bb9850e81..1da1ecf76a0d5 100644
--- a/drivers/vfio/mdev/mdev_driver.c
+++ b/drivers/vfio/mdev/mdev_driver.c
@@ -56,10 +56,9 @@ EXPORT_SYMBOL_GPL(mdev_bus_type);
**/
int mdev_register_driver(struct mdev_driver *drv)
{
- /* initialize common driver fields */
+ if (!drv->types_attrs)
+ return -EINVAL;
drv->driver.bus = &mdev_bus_type;
-
- /* register with core */
return driver_register(&drv->driver);
}
EXPORT_SYMBOL(mdev_register_driver);
diff --git a/drivers/vfio/mdev/mdev_private.h b/drivers/vfio/mdev/mdev_private.h
index 297f911fdc890..ba1b2dbddc0bc 100644
--- a/drivers/vfio/mdev/mdev_private.h
+++ b/drivers/vfio/mdev/mdev_private.h
@@ -13,14 +13,6 @@
int mdev_bus_register(void);
void mdev_bus_unregister(void);
-struct mdev_type {
- struct kobject kobj;
- struct kobject *devices_kobj;
- struct mdev_parent *parent;
- struct list_head next;
- unsigned int type_group_id;
-};
-
extern const struct attribute_group *mdev_device_groups[];
#define to_mdev_type_attr(_attr) \
diff --git a/drivers/vfio/mdev/mdev_sysfs.c b/drivers/vfio/mdev/mdev_sysfs.c
index b71ffc5594870..80b2d546a3d98 100644
--- a/drivers/vfio/mdev/mdev_sysfs.c
+++ b/drivers/vfio/mdev/mdev_sysfs.c
@@ -90,35 +90,21 @@ static struct kobj_type mdev_type_ktype = {
.release = mdev_type_release,
};
-static struct mdev_type *add_mdev_supported_type(struct mdev_parent *parent,
- unsigned int type_group_id)
+static int mdev_type_add(struct mdev_parent *parent, struct mdev_type *type)
{
- struct mdev_type *type;
- struct attribute_group *group =
- parent->mdev_driver->supported_type_groups[type_group_id];
int ret;
- if (!group->name) {
- pr_err("%s: Type name empty!\n", __func__);
- return ERR_PTR(-EINVAL);
- }
-
- type = kzalloc(sizeof(*type), GFP_KERNEL);
- if (!type)
- return ERR_PTR(-ENOMEM);
-
type->kobj.kset = parent->mdev_types_kset;
type->parent = parent;
/* Pairs with the put in mdev_type_release() */
get_device(parent->dev);
- type->type_group_id = type_group_id;
ret = kobject_init_and_add(&type->kobj, &mdev_type_ktype, NULL,
"%s-%s", dev_driver_string(parent->dev),
- group->name);
+ type->sysfs_name);
if (ret) {
kobject_put(&type->kobj);
- return ERR_PTR(ret);
+ return ret;
}
ret = sysfs_create_file(&type->kobj, &mdev_type_attr_create.attr);
@@ -131,13 +117,10 @@ static struct mdev_type *add_mdev_supported_type(struct mdev_parent *parent,
goto attr_devices_failed;
}
- ret = sysfs_create_files(&type->kobj,
- (const struct attribute **)group->attrs);
- if (ret) {
- ret = -ENOMEM;
+ ret = sysfs_create_files(&type->kobj, parent->mdev_driver->types_attrs);
+ if (ret)
goto attrs_failed;
- }
- return type;
+ return 0;
attrs_failed:
kobject_put(type->devices_kobj);
@@ -146,78 +129,49 @@ static struct mdev_type *add_mdev_supported_type(struct mdev_parent *parent,
attr_create_failed:
kobject_del(&type->kobj);
kobject_put(&type->kobj);
- return ERR_PTR(ret);
+ return ret;
}
-static void remove_mdev_supported_type(struct mdev_type *type)
+static void mdev_type_remove(struct mdev_type *type)
{
- struct attribute_group *group =
- type->parent->mdev_driver->supported_type_groups[type->type_group_id];
+ sysfs_remove_files(&type->kobj, type->parent->mdev_driver->types_attrs);
- sysfs_remove_files(&type->kobj,
- (const struct attribute **)group->attrs);
kobject_put(type->devices_kobj);
sysfs_remove_file(&type->kobj, &mdev_type_attr_create.attr);
kobject_del(&type->kobj);
kobject_put(&type->kobj);
}
-static int add_mdev_supported_type_groups(struct mdev_parent *parent)
-{
- int i;
-
- for (i = 0; parent->mdev_driver->supported_type_groups[i]; i++) {
- struct mdev_type *type;
-
- type = add_mdev_supported_type(parent, i);
- if (IS_ERR(type)) {
- struct mdev_type *ltype, *tmp;
-
- list_for_each_entry_safe(ltype, tmp, &parent->type_list,
- next) {
- list_del(<ype->next);
- remove_mdev_supported_type(ltype);
- }
- return PTR_ERR(type);
- }
- list_add(&type->next, &parent->type_list);
- }
- return 0;
-}
-
/* mdev sysfs functions */
void parent_remove_sysfs_files(struct mdev_parent *parent)
{
- struct mdev_type *type, *tmp;
-
- list_for_each_entry_safe(type, tmp, &parent->type_list, next) {
- list_del(&type->next);
- remove_mdev_supported_type(type);
- }
+ int i;
+ for (i = 0; i < parent->nr_types; i++)
+ mdev_type_remove(parent->types[i]);
kset_unregister(parent->mdev_types_kset);
}
int parent_create_sysfs_files(struct mdev_parent *parent)
{
- int ret;
+ int ret, i;
parent->mdev_types_kset = kset_create_and_add("mdev_supported_types",
NULL, &parent->dev->kobj);
-
if (!parent->mdev_types_kset)
return -ENOMEM;
- INIT_LIST_HEAD(&parent->type_list);
-
- ret = add_mdev_supported_type_groups(parent);
- if (ret)
- goto create_err;
+ for (i = 0; i < parent->nr_types; i++) {
+ ret = mdev_type_add(parent, parent->types[i]);
+ if (ret)
+ goto out_err;
+ }
return 0;
-create_err:
- kset_unregister(parent->mdev_types_kset);
- return ret;
+out_err:
+ while (--i >= 0)
+ mdev_type_remove(parent->types[i]);
+ return 0;
}
static ssize_t remove_store(struct device *dev, struct device_attribute *attr,
diff --git a/include/linux/mdev.h b/include/linux/mdev.h
index 327ce3e5c6b5f..cc70cc1e25d91 100644
--- a/include/linux/mdev.h
+++ b/include/linux/mdev.h
@@ -23,14 +23,27 @@ struct mdev_device {
bool active;
};
+struct mdev_type {
+ /* set by the driver before calling mdev_register parent: */
+ const char *sysfs_name;
+
+ /* set by the core, can be used drivers */
+ struct mdev_parent *parent;
+
+ /* internal only */
+ struct kobject kobj;
+ struct kobject *devices_kobj;
+};
+
/* embedded into the struct device that the mdev devices hang off */
struct mdev_parent {
struct device *dev;
struct mdev_driver *mdev_driver;
struct kset *mdev_types_kset;
- struct list_head type_list;
/* Synchronize device creation/removal with parent unregistration */
struct rw_semaphore unreg_sem;
+ struct mdev_type **types;
+ unsigned int nr_types;
};
static inline struct mdev_device *to_mdev_device(struct device *dev)
@@ -38,8 +51,6 @@ static inline struct mdev_device *to_mdev_device(struct device *dev)
return container_of(dev, struct mdev_device, dev);
}
-unsigned int mdev_get_type_group_id(struct mdev_device *mdev);
-unsigned int mtype_get_type_group_id(struct mdev_type *mtype);
struct device *mtype_get_parent_dev(struct mdev_type *mtype);
/* interface for exporting mdev supported type attributes */
@@ -66,15 +77,13 @@ struct mdev_type_attribute mdev_type_attr_##_name = \
* struct mdev_driver - Mediated device driver
* @probe: called when new device created
* @remove: called when device removed
- * @supported_type_groups: Attributes to define supported types. It is mandatory
- * to provide supported types.
+ * @types_attrs: attributes to the type kobjects.
* @driver: device driver structure
- *
**/
struct mdev_driver {
int (*probe)(struct mdev_device *dev);
void (*remove)(struct mdev_device *dev);
- struct attribute_group **supported_type_groups;
+ const struct attribute * const *types_attrs;
struct device_driver driver;
};
@@ -86,7 +95,8 @@ static inline const guid_t *mdev_uuid(struct mdev_device *mdev)
extern struct bus_type mdev_bus_type;
int mdev_register_parent(struct mdev_parent *parent, struct device *dev,
- struct mdev_driver *mdev_driver);
+ struct mdev_driver *mdev_driver, struct mdev_type **types,
+ unsigned int nr_types);
void mdev_unregister_parent(struct mdev_parent *parent);
int mdev_register_driver(struct mdev_driver *drv);
diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c
index 30b3643b3b389..1069f561cb012 100644
--- a/samples/vfio-mdev/mbochs.c
+++ b/samples/vfio-mdev/mbochs.c
@@ -99,23 +99,27 @@ MODULE_PARM_DESC(mem, "megabytes available to " MBOCHS_NAME " devices");
#define MBOCHS_TYPE_2 "medium"
#define MBOCHS_TYPE_3 "large"
-static const struct mbochs_type {
+static struct mbochs_type {
+ struct mdev_type type;
const char *name;
u32 mbytes;
u32 max_x;
u32 max_y;
} mbochs_types[] = {
{
+ .type.sysfs_name = MBOCHS_TYPE_1,
.name = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_1,
.mbytes = 4,
.max_x = 800,
.max_y = 600,
}, {
+ .type.sysfs_name = MBOCHS_TYPE_2,
.name = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_2,
.mbytes = 16,
.max_x = 1920,
.max_y = 1440,
}, {
+ .type.sysfs_name = MBOCHS_TYPE_3,
.name = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_3,
.mbytes = 64,
.max_x = 0,
@@ -123,6 +127,11 @@ static const struct mbochs_type {
},
};
+static struct mdev_type *mbochs_mdev_types[] = {
+ &mbochs_types[0].type,
+ &mbochs_types[1].type,
+ &mbochs_types[2].type,
+};
static dev_t mbochs_devt;
static struct class *mbochs_class;
@@ -508,8 +517,8 @@ static int mbochs_reset(struct mdev_state *mdev_state)
static int mbochs_probe(struct mdev_device *mdev)
{
int avail_mbytes = atomic_read(&mbochs_avail_mbytes);
- const struct mbochs_type *type =
- &mbochs_types[mdev_get_type_group_id(mdev)];
+ struct mbochs_type *type =
+ container_of(mdev->type, struct mbochs_type, type);
struct device *dev = mdev_dev(mdev);
struct mdev_state *mdev_state;
int ret = -ENOMEM;
@@ -1328,8 +1337,8 @@ static const struct attribute_group *mdev_dev_groups[] = {
static ssize_t name_show(struct mdev_type *mtype,
struct mdev_type_attribute *attr, char *buf)
{
- const struct mbochs_type *type =
- &mbochs_types[mtype_get_type_group_id(mtype)];
+ struct mbochs_type *type =
+ container_of(mtype, struct mbochs_type, type);
return sprintf(buf, "%s\n", type->name);
}
@@ -1338,8 +1347,8 @@ static MDEV_TYPE_ATTR_RO(name);
static ssize_t description_show(struct mdev_type *mtype,
struct mdev_type_attribute *attr, char *buf)
{
- const struct mbochs_type *type =
- &mbochs_types[mtype_get_type_group_id(mtype)];
+ struct mbochs_type *type =
+ container_of(mtype, struct mbochs_type, type);
return sprintf(buf, "virtual display, %d MB video memory\n",
type ? type->mbytes : 0);
@@ -1350,8 +1359,8 @@ static ssize_t available_instances_show(struct mdev_type *mtype,
struct mdev_type_attribute *attr,
char *buf)
{
- const struct mbochs_type *type =
- &mbochs_types[mtype_get_type_group_id(mtype)];
+ struct mbochs_type *type =
+ container_of(mtype, struct mbochs_type, type);
int count = atomic_read(&mbochs_avail_mbytes) / type->mbytes;
return sprintf(buf, "%d\n", count);
@@ -1365,7 +1374,7 @@ static ssize_t device_api_show(struct mdev_type *mtype,
}
static MDEV_TYPE_ATTR_RO(device_api);
-static struct attribute *mdev_types_attrs[] = {
+static const struct attribute *mdev_types_attrs[] = {
&mdev_type_attr_name.attr,
&mdev_type_attr_description.attr,
&mdev_type_attr_device_api.attr,
@@ -1373,28 +1382,6 @@ static struct attribute *mdev_types_attrs[] = {
NULL,
};
-static struct attribute_group mdev_type_group1 = {
- .name = MBOCHS_TYPE_1,
- .attrs = mdev_types_attrs,
-};
-
-static struct attribute_group mdev_type_group2 = {
- .name = MBOCHS_TYPE_2,
- .attrs = mdev_types_attrs,
-};
-
-static struct attribute_group mdev_type_group3 = {
- .name = MBOCHS_TYPE_3,
- .attrs = mdev_types_attrs,
-};
-
-static struct attribute_group *mdev_type_groups[] = {
- &mdev_type_group1,
- &mdev_type_group2,
- &mdev_type_group3,
- NULL,
-};
-
static const struct vfio_device_ops mbochs_dev_ops = {
.close_device = mbochs_close_device,
.read = mbochs_read,
@@ -1412,7 +1399,7 @@ static struct mdev_driver mbochs_driver = {
},
.probe = mbochs_probe,
.remove = mbochs_remove,
- .supported_type_groups = mdev_type_groups,
+ .types_attrs = mdev_types_attrs,
};
static const struct file_operations vd_fops = {
@@ -1457,7 +1444,9 @@ static int __init mbochs_dev_init(void)
if (ret)
goto err_class;
- ret = mdev_register_parent(&mbochs_parent, &mbochs_dev, &mbochs_driver);
+ ret = mdev_register_parent(&mbochs_parent, &mbochs_dev, &mbochs_driver,
+ mbochs_mdev_types,
+ ARRAY_SIZE(mbochs_mdev_types));
if (ret)
goto err_device;
diff --git a/samples/vfio-mdev/mdpy.c b/samples/vfio-mdev/mdpy.c
index 132bb055628a6..2052cc27b1c6d 100644
--- a/samples/vfio-mdev/mdpy.c
+++ b/samples/vfio-mdev/mdpy.c
@@ -51,7 +51,8 @@ MODULE_PARM_DESC(count, "number of " MDPY_NAME " devices");
#define MDPY_TYPE_2 "xga"
#define MDPY_TYPE_3 "hd"
-static const struct mdpy_type {
+static struct mdpy_type {
+ struct mdev_type type;
const char *name;
u32 format;
u32 bytepp;
@@ -59,18 +60,21 @@ static const struct mdpy_type {
u32 height;
} mdpy_types[] = {
{
+ .type.sysfs_name = MDPY_TYPE_1,
.name = MDPY_CLASS_NAME "-" MDPY_TYPE_1,
.format = DRM_FORMAT_XRGB8888,
.bytepp = 4,
.width = 640,
.height = 480,
}, {
+ .type.sysfs_name = MDPY_TYPE_2,
.name = MDPY_CLASS_NAME "-" MDPY_TYPE_2,
.format = DRM_FORMAT_XRGB8888,
.bytepp = 4,
.width = 1024,
.height = 768,
}, {
+ .type.sysfs_name = MDPY_TYPE_3,
.name = MDPY_CLASS_NAME "-" MDPY_TYPE_3,
.format = DRM_FORMAT_XRGB8888,
.bytepp = 4,
@@ -79,6 +83,12 @@ static const struct mdpy_type {
},
};
+static struct mdev_type *mdpy_mdev_types[] = {
+ &mdpy_types[0].type,
+ &mdpy_types[1].type,
+ &mdpy_types[2].type,
+};
+
static dev_t mdpy_devt;
static struct class *mdpy_class;
static struct cdev mdpy_cdev;
@@ -219,7 +229,7 @@ static int mdpy_reset(struct mdev_state *mdev_state)
static int mdpy_probe(struct mdev_device *mdev)
{
const struct mdpy_type *type =
- &mdpy_types[mdev_get_type_group_id(mdev)];
+ container_of(mdev->type, struct mdpy_type, type);
struct device *dev = mdev_dev(mdev);
struct mdev_state *mdev_state;
u32 fbsize;
@@ -644,8 +654,7 @@ static const struct attribute_group *mdev_dev_groups[] = {
static ssize_t name_show(struct mdev_type *mtype,
struct mdev_type_attribute *attr, char *buf)
{
- const struct mdpy_type *type =
- &mdpy_types[mtype_get_type_group_id(mtype)];
+ struct mdpy_type *type = container_of(mtype, struct mdpy_type, type);
return sprintf(buf, "%s\n", type->name);
}
@@ -654,8 +663,7 @@ static MDEV_TYPE_ATTR_RO(name);
static ssize_t description_show(struct mdev_type *mtype,
struct mdev_type_attribute *attr, char *buf)
{
- const struct mdpy_type *type =
- &mdpy_types[mtype_get_type_group_id(mtype)];
+ struct mdpy_type *type = container_of(mtype, struct mdpy_type, type);
return sprintf(buf, "virtual display, %dx%d framebuffer\n",
type->width, type->height);
@@ -677,7 +685,7 @@ static ssize_t device_api_show(struct mdev_type *mtype,
}
static MDEV_TYPE_ATTR_RO(device_api);
-static struct attribute *mdev_types_attrs[] = {
+static const struct attribute *mdev_types_attrs[] = {
&mdev_type_attr_name.attr,
&mdev_type_attr_description.attr,
&mdev_type_attr_device_api.attr,
@@ -685,28 +693,6 @@ static struct attribute *mdev_types_attrs[] = {
NULL,
};
-static struct attribute_group mdev_type_group1 = {
- .name = MDPY_TYPE_1,
- .attrs = mdev_types_attrs,
-};
-
-static struct attribute_group mdev_type_group2 = {
- .name = MDPY_TYPE_2,
- .attrs = mdev_types_attrs,
-};
-
-static struct attribute_group mdev_type_group3 = {
- .name = MDPY_TYPE_3,
- .attrs = mdev_types_attrs,
-};
-
-static struct attribute_group *mdev_type_groups[] = {
- &mdev_type_group1,
- &mdev_type_group2,
- &mdev_type_group3,
- NULL,
-};
-
static const struct vfio_device_ops mdpy_dev_ops = {
.read = mdpy_read,
.write = mdpy_write,
@@ -723,7 +709,7 @@ static struct mdev_driver mdpy_driver = {
},
.probe = mdpy_probe,
.remove = mdpy_remove,
- .supported_type_groups = mdev_type_groups,
+ .types_attrs = mdev_types_attrs,
};
static const struct file_operations vd_fops = {
@@ -766,7 +752,9 @@ static int __init mdpy_dev_init(void)
if (ret)
goto err_class;
- ret = mdev_register_parent(&mdpy_parent, &mdpy_dev, &mdpy_driver);
+ ret = mdev_register_parent(&mdpy_parent, &mdpy_dev, &mdpy_driver,
+ mdpy_mdev_types,
+ ARRAY_SIZE(mdpy_mdev_types));
if (ret)
goto err_device;
diff --git a/samples/vfio-mdev/mtty.c b/samples/vfio-mdev/mtty.c
index 8ba5f6084a093..029a19ef8ce7b 100644
--- a/samples/vfio-mdev/mtty.c
+++ b/samples/vfio-mdev/mtty.c
@@ -143,6 +143,20 @@ struct mdev_state {
int nr_ports;
};
+static struct mtty_type {
+ struct mdev_type type;
+ int nr_ports;
+ const char *name;
+} mtty_types[2] = {
+ { .nr_ports = 1, .type.sysfs_name = "1", .name = "Single port serial" },
+ { .nr_ports = 2, .type.sysfs_name = "2", .name = "Dual port serial" },
+};
+
+static struct mdev_type *mtty_mdev_types[] = {
+ &mtty_types[0].type,
+ &mtty_types[1].type,
+};
+
static atomic_t mdev_avail_ports = ATOMIC_INIT(MAX_MTTYS);
static const struct file_operations vd_fops = {
@@ -704,16 +718,18 @@ static ssize_t mdev_access(struct mdev_state *mdev_state, u8 *buf, size_t count,
static int mtty_probe(struct mdev_device *mdev)
{
+ struct mtty_type *type =
+ container_of(mdev->type, struct mtty_type, type);
struct mdev_state *mdev_state;
- int nr_ports = mdev_get_type_group_id(mdev) + 1;
int avail_ports = atomic_read(&mdev_avail_ports);
int ret;
do {
- if (avail_ports < nr_ports)
+ if (avail_ports < type->nr_ports)
return -ENOSPC;
} while (!atomic_try_cmpxchg(&mdev_avail_ports,
- &avail_ports, avail_ports - nr_ports));
+ &avail_ports,
+ avail_ports - type->nr_ports));
mdev_state = kzalloc(sizeof(struct mdev_state), GFP_KERNEL);
if (mdev_state == NULL) {
@@ -723,13 +739,13 @@ static int mtty_probe(struct mdev_device *mdev)
vfio_init_group_dev(&mdev_state->vdev, &mdev->dev, &mtty_dev_ops);
- mdev_state->nr_ports = nr_ports;
+ mdev_state->nr_ports = type->nr_ports;
mdev_state->irq_index = -1;
mdev_state->s[0].max_fifo_size = MAX_FIFO_SIZE;
mdev_state->s[1].max_fifo_size = MAX_FIFO_SIZE;
mutex_init(&mdev_state->rxtx_lock);
- mdev_state->vconfig = kzalloc(MTTY_CONFIG_SPACE_SIZE, GFP_KERNEL);
+ mdev_state->vconfig = kzalloc(MTTY_CONFIG_SPACE_SIZE, GFP_KERNEL);
if (mdev_state->vconfig == NULL) {
ret = -ENOMEM;
goto err_state;
@@ -752,7 +768,7 @@ static int mtty_probe(struct mdev_device *mdev)
vfio_uninit_group_dev(&mdev_state->vdev);
kfree(mdev_state);
err_nr_ports:
- atomic_add(nr_ports, &mdev_avail_ports);
+ atomic_add(type->nr_ports, &mdev_avail_ports);
return ret;
}
@@ -1233,11 +1249,9 @@ static const struct attribute_group *mdev_dev_groups[] = {
static ssize_t name_show(struct mdev_type *mtype,
struct mdev_type_attribute *attr, char *buf)
{
- static const char *name_str[2] = { "Single port serial",
- "Dual port serial" };
+ struct mtty_type *type = container_of(mtype, struct mtty_type, type);
- return sysfs_emit(buf, "%s\n",
- name_str[mtype_get_type_group_id(mtype)]);
+ return sysfs_emit(buf, "%s\n", type->name);
}
static MDEV_TYPE_ATTR_RO(name);
@@ -1246,9 +1260,10 @@ static ssize_t available_instances_show(struct mdev_type *mtype,
struct mdev_type_attribute *attr,
char *buf)
{
- unsigned int ports = mtype_get_type_group_id(mtype) + 1;
+ struct mtty_type *type = container_of(mtype, struct mtty_type, type);
- return sprintf(buf, "%d\n", atomic_read(&mdev_avail_ports) / ports);
+ return sprintf(buf, "%d\n", atomic_read(&mdev_avail_ports) /
+ type->nr_ports);
}
static MDEV_TYPE_ATTR_RO(available_instances);
@@ -1261,29 +1276,13 @@ static ssize_t device_api_show(struct mdev_type *mtype,
static MDEV_TYPE_ATTR_RO(device_api);
-static struct attribute *mdev_types_attrs[] = {
+static const struct attribute *mdev_types_attrs[] = {
&mdev_type_attr_name.attr,
&mdev_type_attr_device_api.attr,
&mdev_type_attr_available_instances.attr,
NULL,
};
-static struct attribute_group mdev_type_group1 = {
- .name = "1",
- .attrs = mdev_types_attrs,
-};
-
-static struct attribute_group mdev_type_group2 = {
- .name = "2",
- .attrs = mdev_types_attrs,
-};
-
-static struct attribute_group *mdev_type_groups[] = {
- &mdev_type_group1,
- &mdev_type_group2,
- NULL,
-};
-
static const struct vfio_device_ops mtty_dev_ops = {
.name = "vfio-mtty",
.read = mtty_read,
@@ -1300,7 +1299,7 @@ static struct mdev_driver mtty_driver = {
},
.probe = mtty_probe,
.remove = mtty_remove,
- .supported_type_groups = mdev_type_groups,
+ .types_attrs = mdev_types_attrs,
};
static void mtty_device_release(struct device *dev)
@@ -1352,7 +1351,8 @@ static int __init mtty_dev_init(void)
goto err_class;
ret = mdev_register_parent(&mtty_dev.parent, &mtty_dev.dev,
- &mtty_driver);
+ &mtty_driver, mtty_mdev_types,
+ ARRAY_SIZE(mtty_mdev_types));
if (ret)
goto err_device;
return 0;
--
2.30.2
^ permalink raw reply related [flat|nested] 31+ messages in thread
* [PATCH 06/15] vfio/mdev: remove mdev_from_dev
2022-07-06 7:42 simplify the mdev interface v5 Christoph Hellwig
` (4 preceding siblings ...)
2022-07-06 7:42 ` [PATCH 05/15] vfio/mdev: simplify mdev_type handling Christoph Hellwig
@ 2022-07-06 7:42 ` Christoph Hellwig
2022-07-06 7:42 ` [PATCH 07/15] vfio/mdev: unexport mdev_bus_type Christoph Hellwig
` (8 subsequent siblings)
14 siblings, 0 replies; 31+ messages in thread
From: Christoph Hellwig @ 2022-07-06 7:42 UTC (permalink / raw)
To: Kirti Wankhede, Tony Krowiak, Halil Pasic, Jason Herne,
Eric Farman, Matthew Rosato, Zhenyu Wang, Zhi Wang,
Alex Williamson
Cc: Jason Gunthorpe, kvm, linux-s390, intel-gvt-dev, Kevin Tian
Just open code it in the only caller.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed By: Kirti Wankhede <kwankhede@nvidia.com>
---
drivers/vfio/mdev/mdev_core.c | 6 ++----
include/linux/mdev.h | 4 ----
2 files changed, 2 insertions(+), 8 deletions(-)
diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c
index 2d95a497fd3b2..bde7ce620dae0 100644
--- a/drivers/vfio/mdev/mdev_core.c
+++ b/drivers/vfio/mdev/mdev_core.c
@@ -53,10 +53,8 @@ static void mdev_device_remove_common(struct mdev_device *mdev)
static int mdev_device_remove_cb(struct device *dev, void *data)
{
- struct mdev_device *mdev = mdev_from_dev(dev);
-
- if (mdev)
- mdev_device_remove_common(mdev);
+ if (dev->bus == &mdev_bus_type)
+ mdev_device_remove_common(to_mdev_device(dev));
return 0;
}
diff --git a/include/linux/mdev.h b/include/linux/mdev.h
index cc70cc1e25d91..411b655c36ab2 100644
--- a/include/linux/mdev.h
+++ b/include/linux/mdev.h
@@ -107,9 +107,5 @@ static inline struct device *mdev_dev(struct mdev_device *mdev)
{
return &mdev->dev;
}
-static inline struct mdev_device *mdev_from_dev(struct device *dev)
-{
- return dev->bus == &mdev_bus_type ? to_mdev_device(dev) : NULL;
-}
#endif /* MDEV_H */
--
2.30.2
^ permalink raw reply related [flat|nested] 31+ messages in thread
* [PATCH 07/15] vfio/mdev: unexport mdev_bus_type
2022-07-06 7:42 simplify the mdev interface v5 Christoph Hellwig
` (5 preceding siblings ...)
2022-07-06 7:42 ` [PATCH 06/15] vfio/mdev: remove mdev_from_dev Christoph Hellwig
@ 2022-07-06 7:42 ` Christoph Hellwig
2022-07-06 7:42 ` [PATCH 08/15] vfio/mdev: remove mdev_parent_dev Christoph Hellwig
` (7 subsequent siblings)
14 siblings, 0 replies; 31+ messages in thread
From: Christoph Hellwig @ 2022-07-06 7:42 UTC (permalink / raw)
To: Kirti Wankhede, Tony Krowiak, Halil Pasic, Jason Herne,
Eric Farman, Matthew Rosato, Zhenyu Wang, Zhi Wang,
Alex Williamson
Cc: Jason Gunthorpe, kvm, linux-s390, intel-gvt-dev, Kevin Tian
mdev_bus_type is only used in mdev.ko now, so unexport it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
---
drivers/vfio/mdev/mdev_driver.c | 1 -
drivers/vfio/mdev/mdev_private.h | 1 +
include/linux/mdev.h | 2 --
3 files changed, 1 insertion(+), 3 deletions(-)
diff --git a/drivers/vfio/mdev/mdev_driver.c b/drivers/vfio/mdev/mdev_driver.c
index 1da1ecf76a0d5..5b3c94f4fb13d 100644
--- a/drivers/vfio/mdev/mdev_driver.c
+++ b/drivers/vfio/mdev/mdev_driver.c
@@ -46,7 +46,6 @@ struct bus_type mdev_bus_type = {
.remove = mdev_remove,
.match = mdev_match,
};
-EXPORT_SYMBOL_GPL(mdev_bus_type);
/**
* mdev_register_driver - register a new MDEV driver
diff --git a/drivers/vfio/mdev/mdev_private.h b/drivers/vfio/mdev/mdev_private.h
index ba1b2dbddc0bc..af457b27f6074 100644
--- a/drivers/vfio/mdev/mdev_private.h
+++ b/drivers/vfio/mdev/mdev_private.h
@@ -13,6 +13,7 @@
int mdev_bus_register(void);
void mdev_bus_unregister(void);
+extern struct bus_type mdev_bus_type;
extern const struct attribute_group *mdev_device_groups[];
#define to_mdev_type_attr(_attr) \
diff --git a/include/linux/mdev.h b/include/linux/mdev.h
index 411b655c36ab2..2ca85b6072b9e 100644
--- a/include/linux/mdev.h
+++ b/include/linux/mdev.h
@@ -92,8 +92,6 @@ static inline const guid_t *mdev_uuid(struct mdev_device *mdev)
return &mdev->uuid;
}
-extern struct bus_type mdev_bus_type;
-
int mdev_register_parent(struct mdev_parent *parent, struct device *dev,
struct mdev_driver *mdev_driver, struct mdev_type **types,
unsigned int nr_types);
--
2.30.2
^ permalink raw reply related [flat|nested] 31+ messages in thread
* [PATCH 08/15] vfio/mdev: remove mdev_parent_dev
2022-07-06 7:42 simplify the mdev interface v5 Christoph Hellwig
` (6 preceding siblings ...)
2022-07-06 7:42 ` [PATCH 07/15] vfio/mdev: unexport mdev_bus_type Christoph Hellwig
@ 2022-07-06 7:42 ` Christoph Hellwig
2022-07-06 7:42 ` [PATCH 09/15] vfio/mdev: remove mtype_get_parent_dev Christoph Hellwig
` (6 subsequent siblings)
14 siblings, 0 replies; 31+ messages in thread
From: Christoph Hellwig @ 2022-07-06 7:42 UTC (permalink / raw)
To: Kirti Wankhede, Tony Krowiak, Halil Pasic, Jason Herne,
Eric Farman, Matthew Rosato, Zhenyu Wang, Zhi Wang,
Alex Williamson
Cc: Jason Gunthorpe, kvm, linux-s390, intel-gvt-dev, Kevin Tian
Just open code the dereferences in the only user.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
---
Documentation/driver-api/vfio-mediated-device.rst | 3 ---
drivers/gpu/drm/i915/gvt/kvmgt.c | 2 +-
drivers/vfio/mdev/mdev_core.c | 6 ------
include/linux/mdev.h | 1 -
4 files changed, 1 insertion(+), 11 deletions(-)
diff --git a/Documentation/driver-api/vfio-mediated-device.rst b/Documentation/driver-api/vfio-mediated-device.rst
index 82a4007bd7207..a4c3a4a168ec6 100644
--- a/Documentation/driver-api/vfio-mediated-device.rst
+++ b/Documentation/driver-api/vfio-mediated-device.rst
@@ -202,9 +202,6 @@ Directories and files under the sysfs for Each Physical Device
sprintf(buf, "%s-%s", dev_driver_string(parent->dev), group->name);
- (or using mdev_parent_dev(mdev) to arrive at the parent device outside
- of the core mdev code)
-
* device_api
This attribute should show which device API is being created, for example,
diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
index ead56e4d30650..3473d4bafd61e 100644
--- a/drivers/gpu/drm/i915/gvt/kvmgt.c
+++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
@@ -1549,7 +1549,7 @@ static const struct vfio_device_ops intel_vgpu_dev_ops = {
static int intel_vgpu_probe(struct mdev_device *mdev)
{
- struct device *pdev = mdev_parent_dev(mdev);
+ struct device *pdev = mdev->type->parent->dev;
struct intel_gvt *gvt = kdev_to_i915(pdev)->gvt;
struct intel_vgpu_type *type =
container_of(mdev->type, struct intel_vgpu_type, type);
diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c
index bde7ce620dae0..75628759a3bf0 100644
--- a/drivers/vfio/mdev/mdev_core.c
+++ b/drivers/vfio/mdev/mdev_core.c
@@ -23,12 +23,6 @@ static struct class_compat *mdev_bus_compat_class;
static LIST_HEAD(mdev_list);
static DEFINE_MUTEX(mdev_list_lock);
-struct device *mdev_parent_dev(struct mdev_device *mdev)
-{
- return mdev->type->parent->dev;
-}
-EXPORT_SYMBOL(mdev_parent_dev);
-
/*
* Used in mdev_type_attribute sysfs functions to return the parent struct
* device
diff --git a/include/linux/mdev.h b/include/linux/mdev.h
index 2ca85b6072b9e..186e5c866871e 100644
--- a/include/linux/mdev.h
+++ b/include/linux/mdev.h
@@ -100,7 +100,6 @@ void mdev_unregister_parent(struct mdev_parent *parent);
int mdev_register_driver(struct mdev_driver *drv);
void mdev_unregister_driver(struct mdev_driver *drv);
-struct device *mdev_parent_dev(struct mdev_device *mdev);
static inline struct device *mdev_dev(struct mdev_device *mdev)
{
return &mdev->dev;
--
2.30.2
^ permalink raw reply related [flat|nested] 31+ messages in thread
* [PATCH 09/15] vfio/mdev: remove mtype_get_parent_dev
2022-07-06 7:42 simplify the mdev interface v5 Christoph Hellwig
` (7 preceding siblings ...)
2022-07-06 7:42 ` [PATCH 08/15] vfio/mdev: remove mdev_parent_dev Christoph Hellwig
@ 2022-07-06 7:42 ` Christoph Hellwig
2022-07-06 7:42 ` [PATCH 10/15] vfio/mdev: consolidate all the device_api sysfs into the core code Christoph Hellwig
` (5 subsequent siblings)
14 siblings, 0 replies; 31+ messages in thread
From: Christoph Hellwig @ 2022-07-06 7:42 UTC (permalink / raw)
To: Kirti Wankhede, Tony Krowiak, Halil Pasic, Jason Herne,
Eric Farman, Matthew Rosato, Zhenyu Wang, Zhi Wang,
Alex Williamson
Cc: Jason Gunthorpe, kvm, linux-s390, intel-gvt-dev, Kevin Tian
Just open code the dereferences in the only user.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
---
drivers/s390/cio/vfio_ccw_ops.c | 3 +--
drivers/vfio/mdev/mdev_core.c | 10 ----------
include/linux/mdev.h | 2 --
3 files changed, 1 insertion(+), 14 deletions(-)
diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c
index 1bb30313a630c..fb62049471ee2 100644
--- a/drivers/s390/cio/vfio_ccw_ops.c
+++ b/drivers/s390/cio/vfio_ccw_ops.c
@@ -88,8 +88,7 @@ static ssize_t available_instances_show(struct mdev_type *mtype,
struct mdev_type_attribute *attr,
char *buf)
{
- struct vfio_ccw_private *private =
- dev_get_drvdata(mtype_get_parent_dev(mtype));
+ struct vfio_ccw_private *private = dev_get_drvdata(mtype->parent->dev);
return sprintf(buf, "%d\n", atomic_read(&private->avail));
}
diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c
index 75628759a3bf0..93f8caf2e5f77 100644
--- a/drivers/vfio/mdev/mdev_core.c
+++ b/drivers/vfio/mdev/mdev_core.c
@@ -23,16 +23,6 @@ static struct class_compat *mdev_bus_compat_class;
static LIST_HEAD(mdev_list);
static DEFINE_MUTEX(mdev_list_lock);
-/*
- * Used in mdev_type_attribute sysfs functions to return the parent struct
- * device
- */
-struct device *mtype_get_parent_dev(struct mdev_type *mtype)
-{
- return mtype->parent->dev;
-}
-EXPORT_SYMBOL(mtype_get_parent_dev);
-
/* Caller must hold parent unreg_sem read or write lock */
static void mdev_device_remove_common(struct mdev_device *mdev)
{
diff --git a/include/linux/mdev.h b/include/linux/mdev.h
index 186e5c866871e..29fc1c853dacc 100644
--- a/include/linux/mdev.h
+++ b/include/linux/mdev.h
@@ -51,8 +51,6 @@ static inline struct mdev_device *to_mdev_device(struct device *dev)
return container_of(dev, struct mdev_device, dev);
}
-struct device *mtype_get_parent_dev(struct mdev_type *mtype);
-
/* interface for exporting mdev supported type attributes */
struct mdev_type_attribute {
struct attribute attr;
--
2.30.2
^ permalink raw reply related [flat|nested] 31+ messages in thread
* [PATCH 10/15] vfio/mdev: consolidate all the device_api sysfs into the core code
2022-07-06 7:42 simplify the mdev interface v5 Christoph Hellwig
` (8 preceding siblings ...)
2022-07-06 7:42 ` [PATCH 09/15] vfio/mdev: remove mtype_get_parent_dev Christoph Hellwig
@ 2022-07-06 7:42 ` Christoph Hellwig
2022-07-06 7:42 ` [PATCH 11/15] vfio/mdev: consolidate all the name " Christoph Hellwig
` (4 subsequent siblings)
14 siblings, 0 replies; 31+ messages in thread
From: Christoph Hellwig @ 2022-07-06 7:42 UTC (permalink / raw)
To: Kirti Wankhede, Tony Krowiak, Halil Pasic, Jason Herne,
Eric Farman, Matthew Rosato, Zhenyu Wang, Zhi Wang,
Alex Williamson
Cc: Jason Gunthorpe, kvm, linux-s390, intel-gvt-dev, Kevin Tian
Every driver just emits a static string, simply feed it through the ops
and provide a standard sysfs show function.
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
---
.../driver-api/vfio-mediated-device.rst | 2 +-
drivers/gpu/drm/i915/gvt/kvmgt.c | 9 +----
drivers/s390/cio/vfio_ccw_ops.c | 9 +----
drivers/s390/crypto/vfio_ap_ops.c | 10 +-----
drivers/vfio/mdev/mdev_driver.c | 4 ++-
drivers/vfio/mdev/mdev_sysfs.c | 35 +++++++++++++------
include/linux/mdev.h | 7 ++--
samples/vfio-mdev/mbochs.c | 9 +----
samples/vfio-mdev/mdpy.c | 9 +----
samples/vfio-mdev/mtty.c | 10 +-----
10 files changed, 37 insertions(+), 67 deletions(-)
diff --git a/Documentation/driver-api/vfio-mediated-device.rst b/Documentation/driver-api/vfio-mediated-device.rst
index a4c3a4a168ec6..c30cb1092bdfb 100644
--- a/Documentation/driver-api/vfio-mediated-device.rst
+++ b/Documentation/driver-api/vfio-mediated-device.rst
@@ -204,7 +204,7 @@ Directories and files under the sysfs for Each Physical Device
* device_api
- This attribute should show which device API is being created, for example,
+ This attribute shows which device API is being created, for example,
"vfio-pci" for a PCI device.
* available_instances
diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
index 3473d4bafd61e..a70610929fed2 100644
--- a/drivers/gpu/drm/i915/gvt/kvmgt.c
+++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
@@ -123,12 +123,6 @@ static ssize_t available_instances_show(struct mdev_type *mtype,
return sprintf(buf, "%u\n", type->avail_instance);
}
-static ssize_t device_api_show(struct mdev_type *mtype,
- struct mdev_type_attribute *attr, char *buf)
-{
- return sprintf(buf, "%s\n", VFIO_DEVICE_API_PCI_STRING);
-}
-
static ssize_t description_show(struct mdev_type *mtype,
struct mdev_type_attribute *attr, char *buf)
{
@@ -151,13 +145,11 @@ static ssize_t name_show(struct mdev_type *mtype,
}
static MDEV_TYPE_ATTR_RO(available_instances);
-static MDEV_TYPE_ATTR_RO(device_api);
static MDEV_TYPE_ATTR_RO(description);
static MDEV_TYPE_ATTR_RO(name);
static const struct attribute *gvt_type_attrs[] = {
&mdev_type_attr_available_instances.attr,
- &mdev_type_attr_device_api.attr,
&mdev_type_attr_description.attr,
&mdev_type_attr_name.attr,
NULL,
@@ -1587,6 +1579,7 @@ static void intel_vgpu_remove(struct mdev_device *mdev)
}
static struct mdev_driver intel_vgpu_mdev_driver = {
+ .device_api = VFIO_DEVICE_API_PCI_STRING,
.driver = {
.name = "intel_vgpu_mdev",
.owner = THIS_MODULE,
diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c
index fb62049471ee2..74ff2d9719d02 100644
--- a/drivers/s390/cio/vfio_ccw_ops.c
+++ b/drivers/s390/cio/vfio_ccw_ops.c
@@ -77,13 +77,6 @@ static ssize_t name_show(struct mdev_type *mtype,
}
static MDEV_TYPE_ATTR_RO(name);
-static ssize_t device_api_show(struct mdev_type *mtype,
- struct mdev_type_attribute *attr, char *buf)
-{
- return sprintf(buf, "%s\n", VFIO_DEVICE_API_CCW_STRING);
-}
-static MDEV_TYPE_ATTR_RO(device_api);
-
static ssize_t available_instances_show(struct mdev_type *mtype,
struct mdev_type_attribute *attr,
char *buf)
@@ -96,7 +89,6 @@ static MDEV_TYPE_ATTR_RO(available_instances);
static const struct attribute *mdev_types_attrs[] = {
&mdev_type_attr_name.attr,
- &mdev_type_attr_device_api.attr,
&mdev_type_attr_available_instances.attr,
NULL,
};
@@ -636,6 +628,7 @@ static const struct vfio_device_ops vfio_ccw_dev_ops = {
};
struct mdev_driver vfio_ccw_mdev_driver = {
+ .device_api = VFIO_DEVICE_API_CCW_STRING,
.driver = {
.name = "vfio_ccw_mdev",
.owner = THIS_MODULE,
diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
index 41e8ecb7f56b9..023b659c812c9 100644
--- a/drivers/s390/crypto/vfio_ap_ops.c
+++ b/drivers/s390/crypto/vfio_ap_ops.c
@@ -529,17 +529,8 @@ static ssize_t available_instances_show(struct mdev_type *mtype,
static MDEV_TYPE_ATTR_RO(available_instances);
-static ssize_t device_api_show(struct mdev_type *mtype,
- struct mdev_type_attribute *attr, char *buf)
-{
- return sprintf(buf, "%s\n", VFIO_DEVICE_API_AP_STRING);
-}
-
-static MDEV_TYPE_ATTR_RO(device_api);
-
static const struct attribute *vfio_ap_mdev_type_attrs[] = {
&mdev_type_attr_name.attr,
- &mdev_type_attr_device_api.attr,
&mdev_type_attr_available_instances.attr,
NULL,
};
@@ -1454,6 +1445,7 @@ static const struct vfio_device_ops vfio_ap_matrix_dev_ops = {
};
static struct mdev_driver vfio_ap_matrix_driver = {
+ .device_api = VFIO_DEVICE_API_AP_STRING,
.driver = {
.name = "vfio_ap_mdev",
.owner = THIS_MODULE,
diff --git a/drivers/vfio/mdev/mdev_driver.c b/drivers/vfio/mdev/mdev_driver.c
index 5b3c94f4fb13d..60e8b9f6474e8 100644
--- a/drivers/vfio/mdev/mdev_driver.c
+++ b/drivers/vfio/mdev/mdev_driver.c
@@ -55,8 +55,10 @@ struct bus_type mdev_bus_type = {
**/
int mdev_register_driver(struct mdev_driver *drv)
{
- if (!drv->types_attrs)
+ if (!drv->types_attrs || !drv->device_api)
return -EINVAL;
+
+ /* initialize common driver fields */
drv->driver.bus = &mdev_bus_type;
return driver_register(&drv->driver);
}
diff --git a/drivers/vfio/mdev/mdev_sysfs.c b/drivers/vfio/mdev/mdev_sysfs.c
index 80b2d546a3d98..89637bc85462a 100644
--- a/drivers/vfio/mdev/mdev_sysfs.c
+++ b/drivers/vfio/mdev/mdev_sysfs.c
@@ -72,9 +72,30 @@ static ssize_t create_store(struct mdev_type *mtype,
return count;
}
-
static MDEV_TYPE_ATTR_WO(create);
+static ssize_t device_api_show(struct mdev_type *mtype,
+ struct mdev_type_attribute *attr, char *buf)
+{
+ return sysfs_emit(buf, "%s\n", mtype->parent->mdev_driver->device_api);
+}
+static MDEV_TYPE_ATTR_RO(device_api);
+
+static struct attribute *mdev_types_core_attrs[] = {
+ &mdev_type_attr_create.attr,
+ &mdev_type_attr_device_api.attr,
+ NULL,
+};
+
+static struct attribute_group mdev_type_core_group = {
+ .attrs = mdev_types_core_attrs,
+};
+
+static const struct attribute_group *mdev_type_groups[] = {
+ &mdev_type_core_group,
+ NULL,
+};
+
static void mdev_type_release(struct kobject *kobj)
{
struct mdev_type *type = to_mdev_type(kobj);
@@ -86,8 +107,9 @@ static void mdev_type_release(struct kobject *kobj)
}
static struct kobj_type mdev_type_ktype = {
- .sysfs_ops = &mdev_type_sysfs_ops,
- .release = mdev_type_release,
+ .sysfs_ops = &mdev_type_sysfs_ops,
+ .release = mdev_type_release,
+ .default_groups = mdev_type_groups,
};
static int mdev_type_add(struct mdev_parent *parent, struct mdev_type *type)
@@ -107,10 +129,6 @@ static int mdev_type_add(struct mdev_parent *parent, struct mdev_type *type)
return ret;
}
- ret = sysfs_create_file(&type->kobj, &mdev_type_attr_create.attr);
- if (ret)
- goto attr_create_failed;
-
type->devices_kobj = kobject_create_and_add("devices", &type->kobj);
if (!type->devices_kobj) {
ret = -ENOMEM;
@@ -125,8 +143,6 @@ static int mdev_type_add(struct mdev_parent *parent, struct mdev_type *type)
attrs_failed:
kobject_put(type->devices_kobj);
attr_devices_failed:
- sysfs_remove_file(&type->kobj, &mdev_type_attr_create.attr);
-attr_create_failed:
kobject_del(&type->kobj);
kobject_put(&type->kobj);
return ret;
@@ -137,7 +153,6 @@ static void mdev_type_remove(struct mdev_type *type)
sysfs_remove_files(&type->kobj, type->parent->mdev_driver->types_attrs);
kobject_put(type->devices_kobj);
- sysfs_remove_file(&type->kobj, &mdev_type_attr_create.attr);
kobject_del(&type->kobj);
kobject_put(&type->kobj);
}
diff --git a/include/linux/mdev.h b/include/linux/mdev.h
index 29fc1c853dacc..51a6f2ddcf9c6 100644
--- a/include/linux/mdev.h
+++ b/include/linux/mdev.h
@@ -61,11 +61,6 @@ struct mdev_type_attribute {
size_t count);
};
-#define MDEV_TYPE_ATTR(_name, _mode, _show, _store) \
-struct mdev_type_attribute mdev_type_attr_##_name = \
- __ATTR(_name, _mode, _show, _store)
-#define MDEV_TYPE_ATTR_RW(_name) \
- struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_RW(_name)
#define MDEV_TYPE_ATTR_RO(_name) \
struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_RO(_name)
#define MDEV_TYPE_ATTR_WO(_name) \
@@ -73,12 +68,14 @@ struct mdev_type_attribute mdev_type_attr_##_name = \
/**
* struct mdev_driver - Mediated device driver
+ * @device_api: string to return for the device_api sysfs
* @probe: called when new device created
* @remove: called when device removed
* @types_attrs: attributes to the type kobjects.
* @driver: device driver structure
**/
struct mdev_driver {
+ const char *device_api;
int (*probe)(struct mdev_device *dev);
void (*remove)(struct mdev_device *dev);
const struct attribute * const *types_attrs;
diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c
index 1069f561cb012..199846f01de92 100644
--- a/samples/vfio-mdev/mbochs.c
+++ b/samples/vfio-mdev/mbochs.c
@@ -1367,17 +1367,9 @@ static ssize_t available_instances_show(struct mdev_type *mtype,
}
static MDEV_TYPE_ATTR_RO(available_instances);
-static ssize_t device_api_show(struct mdev_type *mtype,
- struct mdev_type_attribute *attr, char *buf)
-{
- return sprintf(buf, "%s\n", VFIO_DEVICE_API_PCI_STRING);
-}
-static MDEV_TYPE_ATTR_RO(device_api);
-
static const struct attribute *mdev_types_attrs[] = {
&mdev_type_attr_name.attr,
&mdev_type_attr_description.attr,
- &mdev_type_attr_device_api.attr,
&mdev_type_attr_available_instances.attr,
NULL,
};
@@ -1391,6 +1383,7 @@ static const struct vfio_device_ops mbochs_dev_ops = {
};
static struct mdev_driver mbochs_driver = {
+ .device_api = VFIO_DEVICE_API_PCI_STRING,
.driver = {
.name = "mbochs",
.owner = THIS_MODULE,
diff --git a/samples/vfio-mdev/mdpy.c b/samples/vfio-mdev/mdpy.c
index 2052cc27b1c6d..b8d6eeff2033d 100644
--- a/samples/vfio-mdev/mdpy.c
+++ b/samples/vfio-mdev/mdpy.c
@@ -678,17 +678,9 @@ static ssize_t available_instances_show(struct mdev_type *mtype,
}
static MDEV_TYPE_ATTR_RO(available_instances);
-static ssize_t device_api_show(struct mdev_type *mtype,
- struct mdev_type_attribute *attr, char *buf)
-{
- return sprintf(buf, "%s\n", VFIO_DEVICE_API_PCI_STRING);
-}
-static MDEV_TYPE_ATTR_RO(device_api);
-
static const struct attribute *mdev_types_attrs[] = {
&mdev_type_attr_name.attr,
&mdev_type_attr_description.attr,
- &mdev_type_attr_device_api.attr,
&mdev_type_attr_available_instances.attr,
NULL,
};
@@ -701,6 +693,7 @@ static const struct vfio_device_ops mdpy_dev_ops = {
};
static struct mdev_driver mdpy_driver = {
+ .device_api = VFIO_DEVICE_API_PCI_STRING,
.driver = {
.name = "mdpy",
.owner = THIS_MODULE,
diff --git a/samples/vfio-mdev/mtty.c b/samples/vfio-mdev/mtty.c
index 029a19ef8ce7b..2a470424628af 100644
--- a/samples/vfio-mdev/mtty.c
+++ b/samples/vfio-mdev/mtty.c
@@ -1268,17 +1268,8 @@ static ssize_t available_instances_show(struct mdev_type *mtype,
static MDEV_TYPE_ATTR_RO(available_instances);
-static ssize_t device_api_show(struct mdev_type *mtype,
- struct mdev_type_attribute *attr, char *buf)
-{
- return sprintf(buf, "%s\n", VFIO_DEVICE_API_PCI_STRING);
-}
-
-static MDEV_TYPE_ATTR_RO(device_api);
-
static const struct attribute *mdev_types_attrs[] = {
&mdev_type_attr_name.attr,
- &mdev_type_attr_device_api.attr,
&mdev_type_attr_available_instances.attr,
NULL,
};
@@ -1291,6 +1282,7 @@ static const struct vfio_device_ops mtty_dev_ops = {
};
static struct mdev_driver mtty_driver = {
+ .device_api = VFIO_DEVICE_API_PCI_STRING,
.driver = {
.name = "mtty",
.owner = THIS_MODULE,
--
2.30.2
^ permalink raw reply related [flat|nested] 31+ messages in thread
* [PATCH 11/15] vfio/mdev: consolidate all the name sysfs into the core code
2022-07-06 7:42 simplify the mdev interface v5 Christoph Hellwig
` (9 preceding siblings ...)
2022-07-06 7:42 ` [PATCH 10/15] vfio/mdev: consolidate all the device_api sysfs into the core code Christoph Hellwig
@ 2022-07-06 7:42 ` Christoph Hellwig
2022-07-06 7:42 ` [PATCH 12/15] vfio/mdev: consolidate all the available_instance " Christoph Hellwig
` (3 subsequent siblings)
14 siblings, 0 replies; 31+ messages in thread
From: Christoph Hellwig @ 2022-07-06 7:42 UTC (permalink / raw)
To: Kirti Wankhede, Tony Krowiak, Halil Pasic, Jason Herne,
Eric Farman, Matthew Rosato, Zhenyu Wang, Zhi Wang,
Alex Williamson
Cc: Jason Gunthorpe, kvm, linux-s390, intel-gvt-dev, Kevin Tian
Every driver just emits a static string, simply add a field to the
mdev_type for the driver to fill out or fall back to the sysfs name and
provide a standard sysfs show function.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
---
.../driver-api/vfio-mediated-device.rst | 2 +-
drivers/gpu/drm/i915/gvt/kvmgt.c | 8 -------
drivers/s390/cio/vfio_ccw_ops.c | 9 +-------
drivers/s390/crypto/vfio_ap_ops.c | 9 --------
drivers/vfio/mdev/mdev_sysfs.c | 10 +++++++++
include/linux/mdev.h | 1 +
samples/vfio-mdev/mbochs.c | 20 ++++--------------
samples/vfio-mdev/mdpy.c | 21 +++++--------------
samples/vfio-mdev/mtty.c | 18 ++++------------
9 files changed, 26 insertions(+), 72 deletions(-)
diff --git a/Documentation/driver-api/vfio-mediated-device.rst b/Documentation/driver-api/vfio-mediated-device.rst
index c30cb1092bdfb..334e649360353 100644
--- a/Documentation/driver-api/vfio-mediated-device.rst
+++ b/Documentation/driver-api/vfio-mediated-device.rst
@@ -219,7 +219,7 @@ Directories and files under the sysfs for Each Physical Device
* name
- This attribute should show human readable name. This is optional attribute.
+ This attribute shows a human readable name.
* description
diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
index a70610929fed2..b1b9af88e0fa6 100644
--- a/drivers/gpu/drm/i915/gvt/kvmgt.c
+++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
@@ -138,20 +138,12 @@ static ssize_t description_show(struct mdev_type *mtype,
type->conf->weight);
}
-static ssize_t name_show(struct mdev_type *mtype,
- struct mdev_type_attribute *attr, char *buf)
-{
- return sprintf(buf, "%s\n", mtype->sysfs_name);
-}
-
static MDEV_TYPE_ATTR_RO(available_instances);
static MDEV_TYPE_ATTR_RO(description);
-static MDEV_TYPE_ATTR_RO(name);
static const struct attribute *gvt_type_attrs[] = {
&mdev_type_attr_available_instances.attr,
&mdev_type_attr_description.attr,
- &mdev_type_attr_name.attr,
NULL,
};
diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c
index 74ff2d9719d02..9cc7b68c72f38 100644
--- a/drivers/s390/cio/vfio_ccw_ops.c
+++ b/drivers/s390/cio/vfio_ccw_ops.c
@@ -70,13 +70,6 @@ static int vfio_ccw_mdev_notifier(struct notifier_block *nb,
return NOTIFY_DONE;
}
-static ssize_t name_show(struct mdev_type *mtype,
- struct mdev_type_attribute *attr, char *buf)
-{
- return sprintf(buf, "I/O subchannel (Non-QDIO)\n");
-}
-static MDEV_TYPE_ATTR_RO(name);
-
static ssize_t available_instances_show(struct mdev_type *mtype,
struct mdev_type_attribute *attr,
char *buf)
@@ -88,7 +81,6 @@ static ssize_t available_instances_show(struct mdev_type *mtype,
static MDEV_TYPE_ATTR_RO(available_instances);
static const struct attribute *mdev_types_attrs[] = {
- &mdev_type_attr_name.attr,
&mdev_type_attr_available_instances.attr,
NULL,
};
@@ -642,6 +634,7 @@ struct mdev_driver vfio_ccw_mdev_driver = {
int vfio_ccw_mdev_reg(struct subchannel *sch)
{
sch->mdev_type.sysfs_name = "io";
+ sch->mdev_type.pretty_name = "I/O subchannel (Non-QDIO)";
sch->mdev_types[0] = &sch->mdev_type;
return mdev_register_parent(&sch->parent, &sch->dev,
&vfio_ccw_mdev_driver, sch->mdev_types,
diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
index 023b659c812c9..ed8d0c660e78b 100644
--- a/drivers/s390/crypto/vfio_ap_ops.c
+++ b/drivers/s390/crypto/vfio_ap_ops.c
@@ -511,14 +511,6 @@ static void vfio_ap_mdev_remove(struct mdev_device *mdev)
atomic_inc(&matrix_dev->available_instances);
}
-static ssize_t name_show(struct mdev_type *mtype,
- struct mdev_type_attribute *attr, char *buf)
-{
- return sprintf(buf, "%s\n", VFIO_AP_MDEV_NAME_HWVIRT);
-}
-
-static MDEV_TYPE_ATTR_RO(name);
-
static ssize_t available_instances_show(struct mdev_type *mtype,
struct mdev_type_attribute *attr,
char *buf)
@@ -530,7 +522,6 @@ static ssize_t available_instances_show(struct mdev_type *mtype,
static MDEV_TYPE_ATTR_RO(available_instances);
static const struct attribute *vfio_ap_mdev_type_attrs[] = {
- &mdev_type_attr_name.attr,
&mdev_type_attr_available_instances.attr,
NULL,
};
diff --git a/drivers/vfio/mdev/mdev_sysfs.c b/drivers/vfio/mdev/mdev_sysfs.c
index 89637bc85462a..0f3d0bbf36f75 100644
--- a/drivers/vfio/mdev/mdev_sysfs.c
+++ b/drivers/vfio/mdev/mdev_sysfs.c
@@ -81,9 +81,19 @@ static ssize_t device_api_show(struct mdev_type *mtype,
}
static MDEV_TYPE_ATTR_RO(device_api);
+static ssize_t name_show(struct mdev_type *mtype,
+ struct mdev_type_attribute *attr, char *buf)
+{
+ return sprintf(buf, "%s\n",
+ mtype->pretty_name ? mtype->pretty_name : mtype->sysfs_name);
+}
+
+static MDEV_TYPE_ATTR_RO(name);
+
static struct attribute *mdev_types_core_attrs[] = {
&mdev_type_attr_create.attr,
&mdev_type_attr_device_api.attr,
+ &mdev_type_attr_name.attr,
NULL,
};
diff --git a/include/linux/mdev.h b/include/linux/mdev.h
index 51a6f2ddcf9c6..5e6936bc7fa1b 100644
--- a/include/linux/mdev.h
+++ b/include/linux/mdev.h
@@ -26,6 +26,7 @@ struct mdev_device {
struct mdev_type {
/* set by the driver before calling mdev_register parent: */
const char *sysfs_name;
+ const char *pretty_name;
/* set by the core, can be used drivers */
struct mdev_parent *parent;
diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c
index 199846f01de92..c8271168a96ad 100644
--- a/samples/vfio-mdev/mbochs.c
+++ b/samples/vfio-mdev/mbochs.c
@@ -101,26 +101,25 @@ MODULE_PARM_DESC(mem, "megabytes available to " MBOCHS_NAME " devices");
static struct mbochs_type {
struct mdev_type type;
- const char *name;
u32 mbytes;
u32 max_x;
u32 max_y;
} mbochs_types[] = {
{
.type.sysfs_name = MBOCHS_TYPE_1,
- .name = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_1,
+ .type.pretty_name = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_1,
.mbytes = 4,
.max_x = 800,
.max_y = 600,
}, {
.type.sysfs_name = MBOCHS_TYPE_2,
- .name = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_2,
+ .type.pretty_name = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_2,
.mbytes = 16,
.max_x = 1920,
.max_y = 1440,
}, {
.type.sysfs_name = MBOCHS_TYPE_3,
- .name = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_3,
+ .type.pretty_name = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_3,
.mbytes = 64,
.max_x = 0,
.max_y = 0,
@@ -547,7 +546,7 @@ static int mbochs_probe(struct mdev_device *mdev)
goto err_mem;
dev_info(dev, "%s: %s, %d MB, %ld pages\n", __func__,
- type->name, type->mbytes, mdev_state->pagecount);
+ type->type.pretty_name, type->mbytes, mdev_state->pagecount);
mutex_init(&mdev_state->ops_lock);
mdev_state->mdev = mdev;
@@ -1334,16 +1333,6 @@ static const struct attribute_group *mdev_dev_groups[] = {
NULL,
};
-static ssize_t name_show(struct mdev_type *mtype,
- struct mdev_type_attribute *attr, char *buf)
-{
- struct mbochs_type *type =
- container_of(mtype, struct mbochs_type, type);
-
- return sprintf(buf, "%s\n", type->name);
-}
-static MDEV_TYPE_ATTR_RO(name);
-
static ssize_t description_show(struct mdev_type *mtype,
struct mdev_type_attribute *attr, char *buf)
{
@@ -1368,7 +1357,6 @@ static ssize_t available_instances_show(struct mdev_type *mtype,
static MDEV_TYPE_ATTR_RO(available_instances);
static const struct attribute *mdev_types_attrs[] = {
- &mdev_type_attr_name.attr,
&mdev_type_attr_description.attr,
&mdev_type_attr_available_instances.attr,
NULL,
diff --git a/samples/vfio-mdev/mdpy.c b/samples/vfio-mdev/mdpy.c
index b8d6eeff2033d..6091c642ee102 100644
--- a/samples/vfio-mdev/mdpy.c
+++ b/samples/vfio-mdev/mdpy.c
@@ -53,7 +53,6 @@ MODULE_PARM_DESC(count, "number of " MDPY_NAME " devices");
static struct mdpy_type {
struct mdev_type type;
- const char *name;
u32 format;
u32 bytepp;
u32 width;
@@ -61,21 +60,21 @@ static struct mdpy_type {
} mdpy_types[] = {
{
.type.sysfs_name = MDPY_TYPE_1,
- .name = MDPY_CLASS_NAME "-" MDPY_TYPE_1,
+ .type.pretty_name = MDPY_CLASS_NAME "-" MDPY_TYPE_1,
.format = DRM_FORMAT_XRGB8888,
.bytepp = 4,
.width = 640,
.height = 480,
}, {
.type.sysfs_name = MDPY_TYPE_2,
- .name = MDPY_CLASS_NAME "-" MDPY_TYPE_2,
+ .type.pretty_name = MDPY_CLASS_NAME "-" MDPY_TYPE_2,
.format = DRM_FORMAT_XRGB8888,
.bytepp = 4,
.width = 1024,
.height = 768,
}, {
.type.sysfs_name = MDPY_TYPE_3,
- .name = MDPY_CLASS_NAME "-" MDPY_TYPE_3,
+ .type.pretty_name = MDPY_CLASS_NAME "-" MDPY_TYPE_3,
.format = DRM_FORMAT_XRGB8888,
.bytepp = 4,
.width = 1920,
@@ -256,8 +255,8 @@ static int mdpy_probe(struct mdev_device *mdev)
ret = -ENOMEM;
goto err_vconfig;
}
- dev_info(dev, "%s: %s (%dx%d)\n", __func__, type->name, type->width,
- type->height);
+ dev_info(dev, "%s: %s (%dx%d)\n", __func__, type->type.pretty_name,
+ type->width, type->height);
mutex_init(&mdev_state->ops_lock);
mdev_state->mdev = mdev;
@@ -651,15 +650,6 @@ static const struct attribute_group *mdev_dev_groups[] = {
NULL,
};
-static ssize_t name_show(struct mdev_type *mtype,
- struct mdev_type_attribute *attr, char *buf)
-{
- struct mdpy_type *type = container_of(mtype, struct mdpy_type, type);
-
- return sprintf(buf, "%s\n", type->name);
-}
-static MDEV_TYPE_ATTR_RO(name);
-
static ssize_t description_show(struct mdev_type *mtype,
struct mdev_type_attribute *attr, char *buf)
{
@@ -679,7 +669,6 @@ static ssize_t available_instances_show(struct mdev_type *mtype,
static MDEV_TYPE_ATTR_RO(available_instances);
static const struct attribute *mdev_types_attrs[] = {
- &mdev_type_attr_name.attr,
&mdev_type_attr_description.attr,
&mdev_type_attr_available_instances.attr,
NULL,
diff --git a/samples/vfio-mdev/mtty.c b/samples/vfio-mdev/mtty.c
index 2a470424628af..b95a4491265c5 100644
--- a/samples/vfio-mdev/mtty.c
+++ b/samples/vfio-mdev/mtty.c
@@ -146,10 +146,11 @@ struct mdev_state {
static struct mtty_type {
struct mdev_type type;
int nr_ports;
- const char *name;
} mtty_types[2] = {
- { .nr_ports = 1, .type.sysfs_name = "1", .name = "Single port serial" },
- { .nr_ports = 2, .type.sysfs_name = "2", .name = "Dual port serial" },
+ { .nr_ports = 1, .type.sysfs_name = "1",
+ .type.pretty_name = "Single port serial" },
+ { .nr_ports = 2, .type.sysfs_name = "2",
+ .type.pretty_name = "Dual port serial" },
};
static struct mdev_type *mtty_mdev_types[] = {
@@ -1246,16 +1247,6 @@ static const struct attribute_group *mdev_dev_groups[] = {
NULL,
};
-static ssize_t name_show(struct mdev_type *mtype,
- struct mdev_type_attribute *attr, char *buf)
-{
- struct mtty_type *type = container_of(mtype, struct mtty_type, type);
-
- return sysfs_emit(buf, "%s\n", type->name);
-}
-
-static MDEV_TYPE_ATTR_RO(name);
-
static ssize_t available_instances_show(struct mdev_type *mtype,
struct mdev_type_attribute *attr,
char *buf)
@@ -1269,7 +1260,6 @@ static ssize_t available_instances_show(struct mdev_type *mtype,
static MDEV_TYPE_ATTR_RO(available_instances);
static const struct attribute *mdev_types_attrs[] = {
- &mdev_type_attr_name.attr,
&mdev_type_attr_available_instances.attr,
NULL,
};
--
2.30.2
^ permalink raw reply related [flat|nested] 31+ messages in thread
* [PATCH 12/15] vfio/mdev: consolidate all the available_instance sysfs into the core code
2022-07-06 7:42 simplify the mdev interface v5 Christoph Hellwig
` (10 preceding siblings ...)
2022-07-06 7:42 ` [PATCH 11/15] vfio/mdev: consolidate all the name " Christoph Hellwig
@ 2022-07-06 7:42 ` Christoph Hellwig
2022-07-06 7:42 ` [PATCH 13/15] vfio/mdev: consolidate all the description " Christoph Hellwig
` (2 subsequent siblings)
14 siblings, 0 replies; 31+ messages in thread
From: Christoph Hellwig @ 2022-07-06 7:42 UTC (permalink / raw)
To: Kirti Wankhede, Tony Krowiak, Halil Pasic, Jason Herne,
Eric Farman, Matthew Rosato, Zhenyu Wang, Zhi Wang,
Alex Williamson
Cc: Jason Gunthorpe, kvm, linux-s390, intel-gvt-dev, Kevin Tian
Every driver just print a number, simply add a method to the mdev_driver
to return it and provide a standard sysfs show function.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
---
.../driver-api/vfio-mediated-device.rst | 3 +-
drivers/gpu/drm/i915/gvt/gvt.h | 1 -
drivers/gpu/drm/i915/gvt/kvmgt.c | 34 +++++++++------
drivers/gpu/drm/i915/gvt/vgpu.c | 41 ++-----------------
drivers/s390/cio/vfio_ccw_ops.c | 14 ++-----
drivers/s390/crypto/vfio_ap_ops.c | 16 ++------
drivers/vfio/mdev/mdev_sysfs.c | 11 +++++
include/linux/mdev.h | 2 +
samples/vfio-mdev/mbochs.c | 10 ++---
samples/vfio-mdev/mdpy.c | 9 ++--
samples/vfio-mdev/mtty.c | 16 ++------
11 files changed, 55 insertions(+), 102 deletions(-)
diff --git a/Documentation/driver-api/vfio-mediated-device.rst b/Documentation/driver-api/vfio-mediated-device.rst
index 334e649360353..1e19ba588a34f 100644
--- a/Documentation/driver-api/vfio-mediated-device.rst
+++ b/Documentation/driver-api/vfio-mediated-device.rst
@@ -105,6 +105,7 @@ structure to represent a mediated device's driver::
struct mdev_driver {
int (*probe) (struct mdev_device *dev);
void (*remove) (struct mdev_device *dev);
+ unsigned int (*get_available)(struct mdev_type *mtype);
const struct attribute * const *types_attrs;
struct device_driver driver;
};
@@ -209,7 +210,7 @@ Directories and files under the sysfs for Each Physical Device
* available_instances
- This attribute should show the number of devices of type <type-id> that can be
+ This attribute shows the number of devices of type <type-id> that can be
created.
* [device]
diff --git a/drivers/gpu/drm/i915/gvt/gvt.h b/drivers/gpu/drm/i915/gvt/gvt.h
index f9690dca0a857..994ec48526126 100644
--- a/drivers/gpu/drm/i915/gvt/gvt.h
+++ b/drivers/gpu/drm/i915/gvt/gvt.h
@@ -315,7 +315,6 @@ struct intel_vgpu_type {
struct mdev_type type;
char name[16];
const struct intel_vgpu_config *conf;
- unsigned int avail_instance;
};
struct intel_gvt {
diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
index b1b9af88e0fa6..b523daf048e1f 100644
--- a/drivers/gpu/drm/i915/gvt/kvmgt.c
+++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
@@ -113,16 +113,6 @@ static void kvmgt_page_track_flush_slot(struct kvm *kvm,
struct kvm_memory_slot *slot,
struct kvm_page_track_notifier_node *node);
-static ssize_t available_instances_show(struct mdev_type *mtype,
- struct mdev_type_attribute *attr,
- char *buf)
-{
- struct intel_vgpu_type *type =
- container_of(mtype, struct intel_vgpu_type, type);
-
- return sprintf(buf, "%u\n", type->avail_instance);
-}
-
static ssize_t description_show(struct mdev_type *mtype,
struct mdev_type_attribute *attr, char *buf)
{
@@ -138,11 +128,9 @@ static ssize_t description_show(struct mdev_type *mtype,
type->conf->weight);
}
-static MDEV_TYPE_ATTR_RO(available_instances);
static MDEV_TYPE_ATTR_RO(description);
static const struct attribute *gvt_type_attrs[] = {
- &mdev_type_attr_available_instances.attr,
&mdev_type_attr_description.attr,
NULL,
};
@@ -1570,6 +1558,27 @@ static void intel_vgpu_remove(struct mdev_device *mdev)
intel_gvt_destroy_vgpu(vgpu);
}
+static unsigned int intel_vgpu_get_available(struct mdev_type *mtype)
+{
+ struct intel_vgpu_type *type =
+ container_of(mtype, struct intel_vgpu_type, type);
+ struct intel_gvt *gvt = kdev_to_i915(mtype->parent->dev)->gvt;
+ unsigned int low_gm_avail, high_gm_avail, fence_avail;
+
+ mutex_lock(&gvt->lock);
+ low_gm_avail = gvt_aperture_sz(gvt) - HOST_LOW_GM_SIZE -
+ gvt->gm.vgpu_allocated_low_gm_size;
+ high_gm_avail = gvt_hidden_sz(gvt) - HOST_HIGH_GM_SIZE -
+ gvt->gm.vgpu_allocated_high_gm_size;
+ fence_avail = gvt_fence_sz(gvt) - HOST_FENCE -
+ gvt->fence.vgpu_allocated_fence_num;
+ mutex_unlock(&gvt->lock);
+
+ return min3(low_gm_avail / type->conf->low_mm,
+ high_gm_avail / type->conf->high_mm,
+ fence_avail / type->conf->fence);
+}
+
static struct mdev_driver intel_vgpu_mdev_driver = {
.device_api = VFIO_DEVICE_API_PCI_STRING,
.driver = {
@@ -1579,6 +1588,7 @@ static struct mdev_driver intel_vgpu_mdev_driver = {
},
.probe = intel_vgpu_probe,
.remove = intel_vgpu_remove,
+ .get_available = intel_vgpu_get_available,
.types_attrs = gvt_type_attrs,
};
diff --git a/drivers/gpu/drm/i915/gvt/vgpu.c b/drivers/gpu/drm/i915/gvt/vgpu.c
index ff240503d4125..0723bbee7176f 100644
--- a/drivers/gpu/drm/i915/gvt/vgpu.c
+++ b/drivers/gpu/drm/i915/gvt/vgpu.c
@@ -129,11 +129,11 @@ int intel_gvt_init_vgpu_types(struct intel_gvt *gvt)
sprintf(gvt->types[i].name, "GVTg_V%u_%s",
GRAPHICS_VER(gvt->gt->i915) == 8 ? 4 : 5, conf->name);
gvt->types->conf = conf;
- gvt->types[i].avail_instance = min(low_avail / conf->low_mm,
- high_avail / conf->high_mm);
gvt_dbg_core("type[%d]: %s avail %u low %u high %u fence %u weight %u res %s\n",
- i, gvt->types[i].name, gvt->types[i].avail_instance,
+ i, gvt->types[i].name,
+ min(low_avail / conf->low_mm,
+ high_avail / conf->high_mm),
conf->low_mm, conf->high_mm, conf->fence,
conf->weight, vgpu_edid_str(conf->edid));
@@ -157,36 +157,6 @@ void intel_gvt_clean_vgpu_types(struct intel_gvt *gvt)
kfree(gvt->types);
}
-static void intel_gvt_update_vgpu_types(struct intel_gvt *gvt)
-{
- int i;
- unsigned int low_gm_avail, high_gm_avail, fence_avail;
- unsigned int low_gm_min, high_gm_min, fence_min;
-
- /* Need to depend on maxium hw resource size but keep on
- * static config for now.
- */
- low_gm_avail = gvt_aperture_sz(gvt) - HOST_LOW_GM_SIZE -
- gvt->gm.vgpu_allocated_low_gm_size;
- high_gm_avail = gvt_hidden_sz(gvt) - HOST_HIGH_GM_SIZE -
- gvt->gm.vgpu_allocated_high_gm_size;
- fence_avail = gvt_fence_sz(gvt) - HOST_FENCE -
- gvt->fence.vgpu_allocated_fence_num;
-
- for (i = 0; i < gvt->num_types; i++) {
- low_gm_min = low_gm_avail / gvt->types[i].conf->low_mm;
- high_gm_min = high_gm_avail / gvt->types[i].conf->high_mm;
- fence_min = fence_avail / gvt->types[i].conf->fence;
- gvt->types[i].avail_instance = min(min(low_gm_min, high_gm_min),
- fence_min);
-
- gvt_dbg_core("update type[%d]: %s avail %u low %u high %u fence %u\n",
- i, gvt->types[i].name,
- gvt->types[i].avail_instance, gvt->types[i].conf->low_mm,
- gvt->types[i].conf->high_mm, gvt->types[i].conf->fence);
- }
-}
-
/**
* intel_gvt_active_vgpu - activate a virtual GPU
* @vgpu: virtual GPU
@@ -282,10 +252,6 @@ void intel_gvt_destroy_vgpu(struct intel_vgpu *vgpu)
intel_vgpu_dmabuf_cleanup(vgpu);
mutex_unlock(&vgpu->vgpu_lock);
- mutex_lock(&gvt->lock);
- intel_gvt_update_vgpu_types(gvt);
- mutex_unlock(&gvt->lock);
-
vfree(vgpu);
}
@@ -431,7 +397,6 @@ struct intel_vgpu *intel_gvt_create_vgpu(struct intel_gvt *gvt,
if (ret)
goto out_clean_sched_policy;
- intel_gvt_update_vgpu_types(gvt);
intel_gvt_update_reg_whitelist(vgpu);
mutex_unlock(&gvt->lock);
return vgpu;
diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c
index 9cc7b68c72f38..6f6a0f2695059 100644
--- a/drivers/s390/cio/vfio_ccw_ops.c
+++ b/drivers/s390/cio/vfio_ccw_ops.c
@@ -70,20 +70,12 @@ static int vfio_ccw_mdev_notifier(struct notifier_block *nb,
return NOTIFY_DONE;
}
-static ssize_t available_instances_show(struct mdev_type *mtype,
- struct mdev_type_attribute *attr,
- char *buf)
+static unsigned int vfio_ccw_get_available(struct mdev_type *mtype)
{
struct vfio_ccw_private *private = dev_get_drvdata(mtype->parent->dev);
- return sprintf(buf, "%d\n", atomic_read(&private->avail));
+ return atomic_read(&private->avail);
}
-static MDEV_TYPE_ATTR_RO(available_instances);
-
-static const struct attribute *mdev_types_attrs[] = {
- &mdev_type_attr_available_instances.attr,
- NULL,
-};
static int vfio_ccw_mdev_probe(struct mdev_device *mdev)
{
@@ -628,7 +620,7 @@ struct mdev_driver vfio_ccw_mdev_driver = {
},
.probe = vfio_ccw_mdev_probe,
.remove = vfio_ccw_mdev_remove,
- .types_attrs = mdev_types_attrs,
+ .get_available = vfio_ccw_get_available,
};
int vfio_ccw_mdev_reg(struct subchannel *sch)
diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
index ed8d0c660e78b..edeec11c56560 100644
--- a/drivers/s390/crypto/vfio_ap_ops.c
+++ b/drivers/s390/crypto/vfio_ap_ops.c
@@ -511,21 +511,11 @@ static void vfio_ap_mdev_remove(struct mdev_device *mdev)
atomic_inc(&matrix_dev->available_instances);
}
-static ssize_t available_instances_show(struct mdev_type *mtype,
- struct mdev_type_attribute *attr,
- char *buf)
+static unsigned int vfio_ap_mdev_get_available(struct mdev_type *mtype)
{
- return sprintf(buf, "%d\n",
- atomic_read(&matrix_dev->available_instances));
+ return atomic_read(&matrix_dev->available_instances);
}
-static MDEV_TYPE_ATTR_RO(available_instances);
-
-static const struct attribute *vfio_ap_mdev_type_attrs[] = {
- &mdev_type_attr_available_instances.attr,
- NULL,
-};
-
struct vfio_ap_queue_reserved {
unsigned long *apid;
unsigned long *apqi;
@@ -1445,7 +1435,7 @@ static struct mdev_driver vfio_ap_matrix_driver = {
},
.probe = vfio_ap_mdev_probe,
.remove = vfio_ap_mdev_remove,
- .types_attrs = vfio_ap_mdev_type_attrs,
+ .get_available = vfio_ap_mdev_get_available,
};
int vfio_ap_mdev_register(void)
diff --git a/drivers/vfio/mdev/mdev_sysfs.c b/drivers/vfio/mdev/mdev_sysfs.c
index 0f3d0bbf36f75..9238d92738d5b 100644
--- a/drivers/vfio/mdev/mdev_sysfs.c
+++ b/drivers/vfio/mdev/mdev_sysfs.c
@@ -90,10 +90,21 @@ static ssize_t name_show(struct mdev_type *mtype,
static MDEV_TYPE_ATTR_RO(name);
+static ssize_t available_instances_show(struct mdev_type *mtype,
+ struct mdev_type_attribute *attr,
+ char *buf)
+{
+ struct mdev_driver *drv = mtype->parent->mdev_driver;
+
+ return sysfs_emit(buf, "%u\n", drv->get_available(mtype));
+}
+static MDEV_TYPE_ATTR_RO(available_instances);
+
static struct attribute *mdev_types_core_attrs[] = {
&mdev_type_attr_create.attr,
&mdev_type_attr_device_api.attr,
&mdev_type_attr_name.attr,
+ &mdev_type_attr_available_instances.attr,
NULL,
};
diff --git a/include/linux/mdev.h b/include/linux/mdev.h
index 5e6936bc7fa1b..68b4a132b1523 100644
--- a/include/linux/mdev.h
+++ b/include/linux/mdev.h
@@ -72,6 +72,7 @@ struct mdev_type_attribute {
* @device_api: string to return for the device_api sysfs
* @probe: called when new device created
* @remove: called when device removed
+ * @get_available: Return the max number of instances that can be created
* @types_attrs: attributes to the type kobjects.
* @driver: device driver structure
**/
@@ -79,6 +80,7 @@ struct mdev_driver {
const char *device_api;
int (*probe)(struct mdev_device *dev);
void (*remove)(struct mdev_device *dev);
+ unsigned int (*get_available)(struct mdev_type *mtype);
const struct attribute * const *types_attrs;
struct device_driver driver;
};
diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c
index c8271168a96ad..e61be7f8a9863 100644
--- a/samples/vfio-mdev/mbochs.c
+++ b/samples/vfio-mdev/mbochs.c
@@ -1344,21 +1344,16 @@ static ssize_t description_show(struct mdev_type *mtype,
}
static MDEV_TYPE_ATTR_RO(description);
-static ssize_t available_instances_show(struct mdev_type *mtype,
- struct mdev_type_attribute *attr,
- char *buf)
+static unsigned int mbochs_get_available(struct mdev_type *mtype)
{
struct mbochs_type *type =
container_of(mtype, struct mbochs_type, type);
- int count = atomic_read(&mbochs_avail_mbytes) / type->mbytes;
- return sprintf(buf, "%d\n", count);
+ return atomic_read(&mbochs_avail_mbytes) / type->mbytes;
}
-static MDEV_TYPE_ATTR_RO(available_instances);
static const struct attribute *mdev_types_attrs[] = {
&mdev_type_attr_description.attr,
- &mdev_type_attr_available_instances.attr,
NULL,
};
@@ -1380,6 +1375,7 @@ static struct mdev_driver mbochs_driver = {
},
.probe = mbochs_probe,
.remove = mbochs_remove,
+ .get_available = mbochs_get_available,
.types_attrs = mdev_types_attrs,
};
diff --git a/samples/vfio-mdev/mdpy.c b/samples/vfio-mdev/mdpy.c
index 6091c642ee102..2f59078909c9d 100644
--- a/samples/vfio-mdev/mdpy.c
+++ b/samples/vfio-mdev/mdpy.c
@@ -660,17 +660,13 @@ static ssize_t description_show(struct mdev_type *mtype,
}
static MDEV_TYPE_ATTR_RO(description);
-static ssize_t available_instances_show(struct mdev_type *mtype,
- struct mdev_type_attribute *attr,
- char *buf)
+static unsigned int mdpy_get_available(struct mdev_type *mtype)
{
- return sprintf(buf, "%d\n", max_devices - mdpy_count);
+ return max_devices - mdpy_count;
}
-static MDEV_TYPE_ATTR_RO(available_instances);
static const struct attribute *mdev_types_attrs[] = {
&mdev_type_attr_description.attr,
- &mdev_type_attr_available_instances.attr,
NULL,
};
@@ -691,6 +687,7 @@ static struct mdev_driver mdpy_driver = {
},
.probe = mdpy_probe,
.remove = mdpy_remove,
+ .get_available = mdpy_get_available,
.types_attrs = mdev_types_attrs,
};
diff --git a/samples/vfio-mdev/mtty.c b/samples/vfio-mdev/mtty.c
index b95a4491265c5..f6e8ec8240066 100644
--- a/samples/vfio-mdev/mtty.c
+++ b/samples/vfio-mdev/mtty.c
@@ -1247,23 +1247,13 @@ static const struct attribute_group *mdev_dev_groups[] = {
NULL,
};
-static ssize_t available_instances_show(struct mdev_type *mtype,
- struct mdev_type_attribute *attr,
- char *buf)
+static unsigned int mtty_get_available(struct mdev_type *mtype)
{
struct mtty_type *type = container_of(mtype, struct mtty_type, type);
- return sprintf(buf, "%d\n", atomic_read(&mdev_avail_ports) /
- type->nr_ports);
+ return atomic_read(&mdev_avail_ports) / type->nr_ports;
}
-static MDEV_TYPE_ATTR_RO(available_instances);
-
-static const struct attribute *mdev_types_attrs[] = {
- &mdev_type_attr_available_instances.attr,
- NULL,
-};
-
static const struct vfio_device_ops mtty_dev_ops = {
.name = "vfio-mtty",
.read = mtty_read,
@@ -1281,7 +1271,7 @@ static struct mdev_driver mtty_driver = {
},
.probe = mtty_probe,
.remove = mtty_remove,
- .types_attrs = mdev_types_attrs,
+ .get_available = mtty_get_available,
};
static void mtty_device_release(struct device *dev)
--
2.30.2
^ permalink raw reply related [flat|nested] 31+ messages in thread
* [PATCH 13/15] vfio/mdev: consolidate all the description sysfs into the core code
2022-07-06 7:42 simplify the mdev interface v5 Christoph Hellwig
` (11 preceding siblings ...)
2022-07-06 7:42 ` [PATCH 12/15] vfio/mdev: consolidate all the available_instance " Christoph Hellwig
@ 2022-07-06 7:42 ` Christoph Hellwig
2022-07-06 7:42 ` [PATCH 14/15] vfio/mdev: add mdev available instance checking to the core Christoph Hellwig
2022-07-06 7:42 ` [PATCH 15/15] vfio/mdev: remove an extra parent kobject reference Christoph Hellwig
14 siblings, 0 replies; 31+ messages in thread
From: Christoph Hellwig @ 2022-07-06 7:42 UTC (permalink / raw)
To: Kirti Wankhede, Tony Krowiak, Halil Pasic, Jason Herne,
Eric Farman, Matthew Rosato, Zhenyu Wang, Zhi Wang,
Alex Williamson
Cc: Jason Gunthorpe, kvm, linux-s390, intel-gvt-dev, Kevin Tian
Every driver just emits a string, simply add a method to the mdev_driver
to return it and provide a standard sysfs show function.
Remove the now unused types_attrs field in struct mdev_driver and the
support code for it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
---
.../driver-api/vfio-mediated-device.rst | 4 +-
drivers/gpu/drm/i915/gvt/kvmgt.c | 18 +++------
drivers/vfio/mdev/mdev_driver.c | 2 +-
drivers/vfio/mdev/mdev_sysfs.c | 40 +++++++++++++++----
include/linux/mdev.h | 19 +--------
samples/vfio-mdev/mbochs.c | 11 +----
samples/vfio-mdev/mdpy.c | 11 +----
7 files changed, 46 insertions(+), 59 deletions(-)
diff --git a/Documentation/driver-api/vfio-mediated-device.rst b/Documentation/driver-api/vfio-mediated-device.rst
index 1e19ba588a34f..4f1b9ec6e0ccb 100644
--- a/Documentation/driver-api/vfio-mediated-device.rst
+++ b/Documentation/driver-api/vfio-mediated-device.rst
@@ -106,7 +106,7 @@ structure to represent a mediated device's driver::
int (*probe) (struct mdev_device *dev);
void (*remove) (struct mdev_device *dev);
unsigned int (*get_available)(struct mdev_type *mtype);
- const struct attribute * const *types_attrs;
+ ssize_t (*show_description)(struct mdev_type *mtype, char *buf);
struct device_driver driver;
};
@@ -224,7 +224,7 @@ Directories and files under the sysfs for Each Physical Device
* description
- This attribute should show brief features/description of the type. This is
+ This attribute can show brief features/description of the type. This is an
optional attribute.
Directories and Files Under the sysfs for Each mdev Device
diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
index b523daf048e1f..992a34ec51960 100644
--- a/drivers/gpu/drm/i915/gvt/kvmgt.c
+++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
@@ -113,8 +113,7 @@ static void kvmgt_page_track_flush_slot(struct kvm *kvm,
struct kvm_memory_slot *slot,
struct kvm_page_track_notifier_node *node);
-static ssize_t description_show(struct mdev_type *mtype,
- struct mdev_type_attribute *attr, char *buf)
+static ssize_t intel_vgpu_show_description(struct mdev_type *mtype, char *buf)
{
struct intel_vgpu_type *type =
container_of(mtype, struct intel_vgpu_type, type);
@@ -128,13 +127,6 @@ static ssize_t description_show(struct mdev_type *mtype,
type->conf->weight);
}
-static MDEV_TYPE_ATTR_RO(description);
-
-static const struct attribute *gvt_type_attrs[] = {
- &mdev_type_attr_description.attr,
- NULL,
-};
-
static void gvt_unpin_guest_page(struct intel_vgpu *vgpu, unsigned long gfn,
unsigned long size)
{
@@ -1586,10 +1578,10 @@ static struct mdev_driver intel_vgpu_mdev_driver = {
.owner = THIS_MODULE,
.dev_groups = intel_vgpu_groups,
},
- .probe = intel_vgpu_probe,
- .remove = intel_vgpu_remove,
- .get_available = intel_vgpu_get_available,
- .types_attrs = gvt_type_attrs,
+ .probe = intel_vgpu_probe,
+ .remove = intel_vgpu_remove,
+ .get_available = intel_vgpu_get_available,
+ .show_description = intel_vgpu_show_description,
};
int intel_gvt_page_track_add(struct intel_vgpu *info, u64 gfn)
diff --git a/drivers/vfio/mdev/mdev_driver.c b/drivers/vfio/mdev/mdev_driver.c
index 60e8b9f6474e8..7825d83a55f8c 100644
--- a/drivers/vfio/mdev/mdev_driver.c
+++ b/drivers/vfio/mdev/mdev_driver.c
@@ -55,7 +55,7 @@ struct bus_type mdev_bus_type = {
**/
int mdev_register_driver(struct mdev_driver *drv)
{
- if (!drv->types_attrs || !drv->device_api)
+ if (!drv->device_api)
return -EINVAL;
/* initialize common driver fields */
diff --git a/drivers/vfio/mdev/mdev_sysfs.c b/drivers/vfio/mdev/mdev_sysfs.c
index 9238d92738d5b..c5cd035d591d0 100644
--- a/drivers/vfio/mdev/mdev_sysfs.c
+++ b/drivers/vfio/mdev/mdev_sysfs.c
@@ -14,7 +14,19 @@
#include "mdev_private.h"
-/* Static functions */
+struct mdev_type_attribute {
+ struct attribute attr;
+ ssize_t (*show)(struct mdev_type *mtype,
+ struct mdev_type_attribute *attr, char *buf);
+ ssize_t (*store)(struct mdev_type *mtype,
+ struct mdev_type_attribute *attr, const char *buf,
+ size_t count);
+};
+
+#define MDEV_TYPE_ATTR_RO(_name) \
+ struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_RO(_name)
+#define MDEV_TYPE_ATTR_WO(_name) \
+ struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_WO(_name)
static ssize_t mdev_type_attr_show(struct kobject *kobj,
struct attribute *__attr, char *buf)
@@ -100,16 +112,35 @@ static ssize_t available_instances_show(struct mdev_type *mtype,
}
static MDEV_TYPE_ATTR_RO(available_instances);
+static ssize_t description_show(struct mdev_type *mtype,
+ struct mdev_type_attribute *attr,
+ char *buf)
+{
+ return mtype->parent->mdev_driver->show_description(mtype, buf);
+}
+static MDEV_TYPE_ATTR_RO(description);
+
static struct attribute *mdev_types_core_attrs[] = {
&mdev_type_attr_create.attr,
&mdev_type_attr_device_api.attr,
&mdev_type_attr_name.attr,
&mdev_type_attr_available_instances.attr,
+ &mdev_type_attr_description.attr,
NULL,
};
+static umode_t mdev_types_core_is_visible(struct kobject *kobj,
+ struct attribute *attr, int n)
+{
+ if (attr == &mdev_type_attr_description.attr &&
+ !to_mdev_type(kobj)->parent->mdev_driver->show_description)
+ return 0;
+ return attr->mode;
+}
+
static struct attribute_group mdev_type_core_group = {
.attrs = mdev_types_core_attrs,
+ .is_visible = mdev_types_core_is_visible,
};
static const struct attribute_group *mdev_type_groups[] = {
@@ -156,13 +187,8 @@ static int mdev_type_add(struct mdev_parent *parent, struct mdev_type *type)
goto attr_devices_failed;
}
- ret = sysfs_create_files(&type->kobj, parent->mdev_driver->types_attrs);
- if (ret)
- goto attrs_failed;
return 0;
-attrs_failed:
- kobject_put(type->devices_kobj);
attr_devices_failed:
kobject_del(&type->kobj);
kobject_put(&type->kobj);
@@ -171,8 +197,6 @@ static int mdev_type_add(struct mdev_parent *parent, struct mdev_type *type)
static void mdev_type_remove(struct mdev_type *type)
{
- sysfs_remove_files(&type->kobj, type->parent->mdev_driver->types_attrs);
-
kobject_put(type->devices_kobj);
kobject_del(&type->kobj);
kobject_put(&type->kobj);
diff --git a/include/linux/mdev.h b/include/linux/mdev.h
index 68b4a132b1523..dc38ad2b07883 100644
--- a/include/linux/mdev.h
+++ b/include/linux/mdev.h
@@ -52,28 +52,13 @@ static inline struct mdev_device *to_mdev_device(struct device *dev)
return container_of(dev, struct mdev_device, dev);
}
-/* interface for exporting mdev supported type attributes */
-struct mdev_type_attribute {
- struct attribute attr;
- ssize_t (*show)(struct mdev_type *mtype,
- struct mdev_type_attribute *attr, char *buf);
- ssize_t (*store)(struct mdev_type *mtype,
- struct mdev_type_attribute *attr, const char *buf,
- size_t count);
-};
-
-#define MDEV_TYPE_ATTR_RO(_name) \
- struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_RO(_name)
-#define MDEV_TYPE_ATTR_WO(_name) \
- struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_WO(_name)
-
/**
* struct mdev_driver - Mediated device driver
* @device_api: string to return for the device_api sysfs
* @probe: called when new device created
* @remove: called when device removed
* @get_available: Return the max number of instances that can be created
- * @types_attrs: attributes to the type kobjects.
+ * @show_description: Print a description of the mtype
* @driver: device driver structure
**/
struct mdev_driver {
@@ -81,7 +66,7 @@ struct mdev_driver {
int (*probe)(struct mdev_device *dev);
void (*remove)(struct mdev_device *dev);
unsigned int (*get_available)(struct mdev_type *mtype);
- const struct attribute * const *types_attrs;
+ ssize_t (*show_description)(struct mdev_type *mtype, char *buf);
struct device_driver driver;
};
diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c
index e61be7f8a9863..0f9b9cf46f05b 100644
--- a/samples/vfio-mdev/mbochs.c
+++ b/samples/vfio-mdev/mbochs.c
@@ -1333,8 +1333,7 @@ static const struct attribute_group *mdev_dev_groups[] = {
NULL,
};
-static ssize_t description_show(struct mdev_type *mtype,
- struct mdev_type_attribute *attr, char *buf)
+static ssize_t mbochs_show_description(struct mdev_type *mtype, char *buf)
{
struct mbochs_type *type =
container_of(mtype, struct mbochs_type, type);
@@ -1342,7 +1341,6 @@ static ssize_t description_show(struct mdev_type *mtype,
return sprintf(buf, "virtual display, %d MB video memory\n",
type ? type->mbytes : 0);
}
-static MDEV_TYPE_ATTR_RO(description);
static unsigned int mbochs_get_available(struct mdev_type *mtype)
{
@@ -1352,11 +1350,6 @@ static unsigned int mbochs_get_available(struct mdev_type *mtype)
return atomic_read(&mbochs_avail_mbytes) / type->mbytes;
}
-static const struct attribute *mdev_types_attrs[] = {
- &mdev_type_attr_description.attr,
- NULL,
-};
-
static const struct vfio_device_ops mbochs_dev_ops = {
.close_device = mbochs_close_device,
.read = mbochs_read,
@@ -1376,7 +1369,7 @@ static struct mdev_driver mbochs_driver = {
.probe = mbochs_probe,
.remove = mbochs_remove,
.get_available = mbochs_get_available,
- .types_attrs = mdev_types_attrs,
+ .show_description = mbochs_show_description,
};
static const struct file_operations vd_fops = {
diff --git a/samples/vfio-mdev/mdpy.c b/samples/vfio-mdev/mdpy.c
index 2f59078909c9d..250b7ea2df2e4 100644
--- a/samples/vfio-mdev/mdpy.c
+++ b/samples/vfio-mdev/mdpy.c
@@ -650,26 +650,19 @@ static const struct attribute_group *mdev_dev_groups[] = {
NULL,
};
-static ssize_t description_show(struct mdev_type *mtype,
- struct mdev_type_attribute *attr, char *buf)
+static ssize_t mdpy_show_description(struct mdev_type *mtype, char *buf)
{
struct mdpy_type *type = container_of(mtype, struct mdpy_type, type);
return sprintf(buf, "virtual display, %dx%d framebuffer\n",
type->width, type->height);
}
-static MDEV_TYPE_ATTR_RO(description);
static unsigned int mdpy_get_available(struct mdev_type *mtype)
{
return max_devices - mdpy_count;
}
-static const struct attribute *mdev_types_attrs[] = {
- &mdev_type_attr_description.attr,
- NULL,
-};
-
static const struct vfio_device_ops mdpy_dev_ops = {
.read = mdpy_read,
.write = mdpy_write,
@@ -688,7 +681,7 @@ static struct mdev_driver mdpy_driver = {
.probe = mdpy_probe,
.remove = mdpy_remove,
.get_available = mdpy_get_available,
- .types_attrs = mdev_types_attrs,
+ .show_description = mdpy_show_description,
};
static const struct file_operations vd_fops = {
--
2.30.2
^ permalink raw reply related [flat|nested] 31+ messages in thread
* [PATCH 14/15] vfio/mdev: add mdev available instance checking to the core
2022-07-06 7:42 simplify the mdev interface v5 Christoph Hellwig
` (12 preceding siblings ...)
2022-07-06 7:42 ` [PATCH 13/15] vfio/mdev: consolidate all the description " Christoph Hellwig
@ 2022-07-06 7:42 ` Christoph Hellwig
2022-07-06 13:37 ` Kirti Wankhede
2022-07-07 3:08 ` Eric Farman
2022-07-06 7:42 ` [PATCH 15/15] vfio/mdev: remove an extra parent kobject reference Christoph Hellwig
14 siblings, 2 replies; 31+ messages in thread
From: Christoph Hellwig @ 2022-07-06 7:42 UTC (permalink / raw)
To: Kirti Wankhede, Tony Krowiak, Halil Pasic, Jason Herne,
Eric Farman, Matthew Rosato, Zhenyu Wang, Zhi Wang,
Alex Williamson
Cc: Jason Gunthorpe, kvm, linux-s390, intel-gvt-dev, Kevin Tian
Many of the mdev drivers use a simple counter for keeping track of the
available instances. Move this code to the core code and store the counter
in the mdev_parent. Implement it using correct locking, fixing mdpy.
Drivers just provide the value in the mdev_driver at registration time
and the core code takes care of maintaining it and exposing the value in
sysfs.
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
[count instances per-parent instead of per-type]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
---
drivers/s390/cio/vfio_ccw_drv.c | 1 -
drivers/s390/cio/vfio_ccw_ops.c | 14 +-------------
drivers/s390/cio/vfio_ccw_private.h | 2 --
drivers/s390/crypto/vfio_ap_ops.c | 21 +++------------------
drivers/s390/crypto/vfio_ap_private.h | 2 --
drivers/vfio/mdev/mdev_core.c | 18 +++++++++++++++---
include/linux/mdev.h | 3 +++
samples/vfio-mdev/mdpy.c | 23 ++++-------------------
8 files changed, 26 insertions(+), 58 deletions(-)
diff --git a/drivers/s390/cio/vfio_ccw_drv.c b/drivers/s390/cio/vfio_ccw_drv.c
index 750d0315f1f5b..449c76b29a3b5 100644
--- a/drivers/s390/cio/vfio_ccw_drv.c
+++ b/drivers/s390/cio/vfio_ccw_drv.c
@@ -149,7 +149,6 @@ static struct vfio_ccw_private *vfio_ccw_alloc_private(struct subchannel *sch)
INIT_LIST_HEAD(&private->crw);
INIT_WORK(&private->io_work, vfio_ccw_sch_io_todo);
INIT_WORK(&private->crw_work, vfio_ccw_crw_todo);
- atomic_set(&private->avail, 1);
private->cp.guest_cp = kcalloc(CCWCHAIN_LEN_MAX, sizeof(struct ccw1),
GFP_KERNEL);
diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c
index 6f6a0f2695059..c05d80add7be2 100644
--- a/drivers/s390/cio/vfio_ccw_ops.c
+++ b/drivers/s390/cio/vfio_ccw_ops.c
@@ -70,13 +70,6 @@ static int vfio_ccw_mdev_notifier(struct notifier_block *nb,
return NOTIFY_DONE;
}
-static unsigned int vfio_ccw_get_available(struct mdev_type *mtype)
-{
- struct vfio_ccw_private *private = dev_get_drvdata(mtype->parent->dev);
-
- return atomic_read(&private->avail);
-}
-
static int vfio_ccw_mdev_probe(struct mdev_device *mdev)
{
struct vfio_ccw_private *private = dev_get_drvdata(mdev->dev.parent);
@@ -85,9 +78,6 @@ static int vfio_ccw_mdev_probe(struct mdev_device *mdev)
if (private->state == VFIO_CCW_STATE_NOT_OPER)
return -ENODEV;
- if (atomic_dec_if_positive(&private->avail) < 0)
- return -EPERM;
-
memset(&private->vdev, 0, sizeof(private->vdev));
vfio_init_group_dev(&private->vdev, &mdev->dev,
&vfio_ccw_dev_ops);
@@ -108,7 +98,6 @@ static int vfio_ccw_mdev_probe(struct mdev_device *mdev)
err_atomic:
vfio_uninit_group_dev(&private->vdev);
- atomic_inc(&private->avail);
private->mdev = NULL;
private->state = VFIO_CCW_STATE_IDLE;
return ret;
@@ -135,7 +124,6 @@ static void vfio_ccw_mdev_remove(struct mdev_device *mdev)
vfio_uninit_group_dev(&private->vdev);
cp_free(&private->cp);
private->mdev = NULL;
- atomic_inc(&private->avail);
}
static int vfio_ccw_mdev_open_device(struct vfio_device *vdev)
@@ -613,6 +601,7 @@ static const struct vfio_device_ops vfio_ccw_dev_ops = {
struct mdev_driver vfio_ccw_mdev_driver = {
.device_api = VFIO_DEVICE_API_CCW_STRING,
+ .max_instances = 1,
.driver = {
.name = "vfio_ccw_mdev",
.owner = THIS_MODULE,
@@ -620,7 +609,6 @@ struct mdev_driver vfio_ccw_mdev_driver = {
},
.probe = vfio_ccw_mdev_probe,
.remove = vfio_ccw_mdev_remove,
- .get_available = vfio_ccw_get_available,
};
int vfio_ccw_mdev_reg(struct subchannel *sch)
diff --git a/drivers/s390/cio/vfio_ccw_private.h b/drivers/s390/cio/vfio_ccw_private.h
index b7163bac8cc75..9be5baed0cb7f 100644
--- a/drivers/s390/cio/vfio_ccw_private.h
+++ b/drivers/s390/cio/vfio_ccw_private.h
@@ -72,7 +72,6 @@ struct vfio_ccw_crw {
* @sch: pointer to the subchannel
* @state: internal state of the device
* @completion: synchronization helper of the I/O completion
- * @avail: available for creating a mediated device
* @mdev: pointer to the mediated device
* @nb: notifier for vfio events
* @io_region: MMIO region to input/output I/O arguments/results
@@ -96,7 +95,6 @@ struct vfio_ccw_private {
struct subchannel *sch;
int state;
struct completion *completion;
- atomic_t avail;
struct mdev_device *mdev;
struct notifier_block nb;
struct ccw_io_region *io_region;
diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
index edeec11c56560..69ed88fdaf383 100644
--- a/drivers/s390/crypto/vfio_ap_ops.c
+++ b/drivers/s390/crypto/vfio_ap_ops.c
@@ -461,14 +461,9 @@ static int vfio_ap_mdev_probe(struct mdev_device *mdev)
struct ap_matrix_mdev *matrix_mdev;
int ret;
- if ((atomic_dec_if_positive(&matrix_dev->available_instances) < 0))
- return -EPERM;
-
matrix_mdev = kzalloc(sizeof(*matrix_mdev), GFP_KERNEL);
- if (!matrix_mdev) {
- ret = -ENOMEM;
- goto err_dec_available;
- }
+ if (!matrix_mdev)
+ return -ENOMEM;
vfio_init_group_dev(&matrix_mdev->vdev, &mdev->dev,
&vfio_ap_matrix_dev_ops);
@@ -491,8 +486,6 @@ static int vfio_ap_mdev_probe(struct mdev_device *mdev)
mutex_unlock(&matrix_dev->lock);
vfio_uninit_group_dev(&matrix_mdev->vdev);
kfree(matrix_mdev);
-err_dec_available:
- atomic_inc(&matrix_dev->available_instances);
return ret;
}
@@ -508,12 +501,6 @@ static void vfio_ap_mdev_remove(struct mdev_device *mdev)
mutex_unlock(&matrix_dev->lock);
vfio_uninit_group_dev(&matrix_mdev->vdev);
kfree(matrix_mdev);
- atomic_inc(&matrix_dev->available_instances);
-}
-
-static unsigned int vfio_ap_mdev_get_available(struct mdev_type *mtype)
-{
- return atomic_read(&matrix_dev->available_instances);
}
struct vfio_ap_queue_reserved {
@@ -1427,6 +1414,7 @@ static const struct vfio_device_ops vfio_ap_matrix_dev_ops = {
static struct mdev_driver vfio_ap_matrix_driver = {
.device_api = VFIO_DEVICE_API_AP_STRING,
+ .max_instances = MAX_ZDEV_ENTRIES_EXT,
.driver = {
.name = "vfio_ap_mdev",
.owner = THIS_MODULE,
@@ -1435,15 +1423,12 @@ static struct mdev_driver vfio_ap_matrix_driver = {
},
.probe = vfio_ap_mdev_probe,
.remove = vfio_ap_mdev_remove,
- .get_available = vfio_ap_mdev_get_available,
};
int vfio_ap_mdev_register(void)
{
int ret;
- atomic_set(&matrix_dev->available_instances, MAX_ZDEV_ENTRIES_EXT);
-
ret = mdev_register_driver(&vfio_ap_matrix_driver);
if (ret)
return ret;
diff --git a/drivers/s390/crypto/vfio_ap_private.h b/drivers/s390/crypto/vfio_ap_private.h
index 5dc5050d03791..b808b343b771f 100644
--- a/drivers/s390/crypto/vfio_ap_private.h
+++ b/drivers/s390/crypto/vfio_ap_private.h
@@ -28,7 +28,6 @@
* struct ap_matrix_dev - Contains the data for the matrix device.
*
* @device: generic device structure associated with the AP matrix device
- * @available_instances: number of mediated matrix devices that can be created
* @info: the struct containing the output from the PQAP(QCI) instruction
* @mdev_list: the list of mediated matrix devices created
* @lock: mutex for locking the AP matrix device. This lock will be
@@ -40,7 +39,6 @@
*/
struct ap_matrix_dev {
struct device device;
- atomic_t available_instances;
struct ap_config_info info;
struct list_head mdev_list;
struct mutex lock;
diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c
index 93f8caf2e5f77..9bc897235c492 100644
--- a/drivers/vfio/mdev/mdev_core.c
+++ b/drivers/vfio/mdev/mdev_core.c
@@ -70,6 +70,7 @@ int mdev_register_parent(struct mdev_parent *parent, struct device *dev,
parent->mdev_driver = mdev_driver;
parent->types = types;
parent->nr_types = nr_types;
+ parent->available_instances = mdev_driver->max_instances;
if (!mdev_bus_compat_class) {
mdev_bus_compat_class = class_compat_register("mdev_bus");
@@ -115,14 +116,17 @@ EXPORT_SYMBOL(mdev_unregister_parent);
static void mdev_device_release(struct device *dev)
{
struct mdev_device *mdev = to_mdev_device(dev);
-
- /* Pairs with the get in mdev_device_create() */
- kobject_put(&mdev->type->kobj);
+ struct mdev_parent *parent = mdev->type->parent;
mutex_lock(&mdev_list_lock);
list_del(&mdev->next);
+ if (!parent->mdev_driver->get_available)
+ parent->available_instances++;
mutex_unlock(&mdev_list_lock);
+ /* Pairs with the get in mdev_device_create() */
+ kobject_put(&mdev->type->kobj);
+
dev_dbg(&mdev->dev, "MDEV: destroying\n");
kfree(mdev);
}
@@ -144,6 +148,14 @@ int mdev_device_create(struct mdev_type *type, const guid_t *uuid)
}
}
+ if (!drv->get_available) {
+ if (!parent->available_instances) {
+ mutex_unlock(&mdev_list_lock);
+ return -EUSERS;
+ }
+ parent->available_instances--;
+ }
+
mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
if (!mdev) {
mutex_unlock(&mdev_list_lock);
diff --git a/include/linux/mdev.h b/include/linux/mdev.h
index dc38ad2b07883..641ed18a61247 100644
--- a/include/linux/mdev.h
+++ b/include/linux/mdev.h
@@ -45,6 +45,7 @@ struct mdev_parent {
struct rw_semaphore unreg_sem;
struct mdev_type **types;
unsigned int nr_types;
+ unsigned int available_instances;
};
static inline struct mdev_device *to_mdev_device(struct device *dev)
@@ -55,6 +56,7 @@ static inline struct mdev_device *to_mdev_device(struct device *dev)
/**
* struct mdev_driver - Mediated device driver
* @device_api: string to return for the device_api sysfs
+ * @max_instances: maximum number of instances supported (optional)
* @probe: called when new device created
* @remove: called when device removed
* @get_available: Return the max number of instances that can be created
@@ -63,6 +65,7 @@ static inline struct mdev_device *to_mdev_device(struct device *dev)
**/
struct mdev_driver {
const char *device_api;
+ unsigned int max_instances;
int (*probe)(struct mdev_device *dev);
void (*remove)(struct mdev_device *dev);
unsigned int (*get_available)(struct mdev_type *mtype);
diff --git a/samples/vfio-mdev/mdpy.c b/samples/vfio-mdev/mdpy.c
index 250b7ea2df2e4..7f7ac5491407e 100644
--- a/samples/vfio-mdev/mdpy.c
+++ b/samples/vfio-mdev/mdpy.c
@@ -42,11 +42,6 @@
MODULE_LICENSE("GPL v2");
-static int max_devices = 4;
-module_param_named(count, max_devices, int, 0444);
-MODULE_PARM_DESC(count, "number of " MDPY_NAME " devices");
-
-
#define MDPY_TYPE_1 "vga"
#define MDPY_TYPE_2 "xga"
#define MDPY_TYPE_3 "hd"
@@ -93,7 +88,6 @@ static struct class *mdpy_class;
static struct cdev mdpy_cdev;
static struct device mdpy_dev;
static struct mdev_parent mdpy_parent;
-static u32 mdpy_count;
static const struct vfio_device_ops mdpy_dev_ops;
/* State of each mdev device */
@@ -234,9 +228,6 @@ static int mdpy_probe(struct mdev_device *mdev)
u32 fbsize;
int ret;
- if (mdpy_count >= max_devices)
- return -ENOMEM;
-
mdev_state = kzalloc(sizeof(struct mdev_state), GFP_KERNEL);
if (mdev_state == NULL)
return -ENOMEM;
@@ -265,8 +256,6 @@ static int mdpy_probe(struct mdev_device *mdev)
mdpy_create_config_space(mdev_state);
mdpy_reset(mdev_state);
- mdpy_count++;
-
ret = vfio_register_emulated_iommu_dev(&mdev_state->vdev);
if (ret)
goto err_mem;
@@ -293,8 +282,6 @@ static void mdpy_remove(struct mdev_device *mdev)
kfree(mdev_state->vconfig);
vfio_uninit_group_dev(&mdev_state->vdev);
kfree(mdev_state);
-
- mdpy_count--;
}
static ssize_t mdpy_read(struct vfio_device *vdev, char __user *buf,
@@ -658,11 +645,6 @@ static ssize_t mdpy_show_description(struct mdev_type *mtype, char *buf)
type->width, type->height);
}
-static unsigned int mdpy_get_available(struct mdev_type *mtype)
-{
- return max_devices - mdpy_count;
-}
-
static const struct vfio_device_ops mdpy_dev_ops = {
.read = mdpy_read,
.write = mdpy_write,
@@ -672,6 +654,7 @@ static const struct vfio_device_ops mdpy_dev_ops = {
static struct mdev_driver mdpy_driver = {
.device_api = VFIO_DEVICE_API_PCI_STRING,
+ .max_instances = 4,
.driver = {
.name = "mdpy",
.owner = THIS_MODULE,
@@ -680,7 +663,6 @@ static struct mdev_driver mdpy_driver = {
},
.probe = mdpy_probe,
.remove = mdpy_remove,
- .get_available = mdpy_get_available,
.show_description = mdpy_show_description,
};
@@ -757,5 +739,8 @@ static void __exit mdpy_dev_exit(void)
mdpy_class = NULL;
}
+module_param_named(count, mdpy_driver.max_instances, int, 0444);
+MODULE_PARM_DESC(count, "number of " MDPY_NAME " devices");
+
module_init(mdpy_dev_init)
module_exit(mdpy_dev_exit)
--
2.30.2
^ permalink raw reply related [flat|nested] 31+ messages in thread
* [PATCH 15/15] vfio/mdev: remove an extra parent kobject reference
2022-07-06 7:42 simplify the mdev interface v5 Christoph Hellwig
` (13 preceding siblings ...)
2022-07-06 7:42 ` [PATCH 14/15] vfio/mdev: add mdev available instance checking to the core Christoph Hellwig
@ 2022-07-06 7:42 ` Christoph Hellwig
2022-07-06 13:48 ` Kirti Wankhede
` (2 more replies)
14 siblings, 3 replies; 31+ messages in thread
From: Christoph Hellwig @ 2022-07-06 7:42 UTC (permalink / raw)
To: Kirti Wankhede, Tony Krowiak, Halil Pasic, Jason Herne,
Eric Farman, Matthew Rosato, Zhenyu Wang, Zhi Wang,
Alex Williamson
Cc: Jason Gunthorpe, kvm, linux-s390, intel-gvt-dev
The mdev_type already holds a reference to the parent through
mdev_types_kset, so drop the extra reference.
Suggested-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
drivers/vfio/mdev/mdev_sysfs.c | 9 +--------
1 file changed, 1 insertion(+), 8 deletions(-)
diff --git a/drivers/vfio/mdev/mdev_sysfs.c b/drivers/vfio/mdev/mdev_sysfs.c
index c5cd035d591d0..e2087cac1c859 100644
--- a/drivers/vfio/mdev/mdev_sysfs.c
+++ b/drivers/vfio/mdev/mdev_sysfs.c
@@ -153,8 +153,6 @@ static void mdev_type_release(struct kobject *kobj)
struct mdev_type *type = to_mdev_type(kobj);
pr_debug("Releasing group %s\n", kobj->name);
- /* Pairs with the get in add_mdev_supported_type() */
- put_device(type->parent->dev);
kfree(type);
}
@@ -170,16 +168,12 @@ static int mdev_type_add(struct mdev_parent *parent, struct mdev_type *type)
type->kobj.kset = parent->mdev_types_kset;
type->parent = parent;
- /* Pairs with the put in mdev_type_release() */
- get_device(parent->dev);
ret = kobject_init_and_add(&type->kobj, &mdev_type_ktype, NULL,
"%s-%s", dev_driver_string(parent->dev),
type->sysfs_name);
- if (ret) {
- kobject_put(&type->kobj);
+ if (ret)
return ret;
- }
type->devices_kobj = kobject_create_and_add("devices", &type->kobj);
if (!type->devices_kobj) {
@@ -191,7 +185,6 @@ static int mdev_type_add(struct mdev_parent *parent, struct mdev_type *type)
attr_devices_failed:
kobject_del(&type->kobj);
- kobject_put(&type->kobj);
return ret;
}
--
2.30.2
^ permalink raw reply related [flat|nested] 31+ messages in thread
* Re: [PATCH 04/15] vfio/mdev: embedd struct mdev_parent in the parent data structure
2022-07-06 7:42 ` [PATCH 04/15] vfio/mdev: embedd struct mdev_parent in the parent data structure Christoph Hellwig
@ 2022-07-06 13:29 ` Kirti Wankhede
2022-07-07 3:08 ` Eric Farman
1 sibling, 0 replies; 31+ messages in thread
From: Kirti Wankhede @ 2022-07-06 13:29 UTC (permalink / raw)
To: Christoph Hellwig, Tony Krowiak, Halil Pasic, Jason Herne,
Eric Farman, Matthew Rosato, Zhenyu Wang, Zhi Wang,
Alex Williamson
Cc: Jason Gunthorpe, kvm, linux-s390, intel-gvt-dev, Kevin Tian,
Tarun Gupta, Shounak Deshpande, Neo Jia
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
On 7/6/2022 1:12 PM, Christoph Hellwig wrote:
> Simplify mdev_{un}register_device by requiring the caller to pass in
> a structure allocate as part of the parent device structure. This
> removes the need for a list of parents and the separate mdev_parent
> refcount as we can simplify rely on the reference to the parent device.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
> Reviewed-by: Kevin Tian <kevin.tian@intel.com>
> ---
> .../driver-api/vfio-mediated-device.rst | 12 +-
> Documentation/s390/vfio-ap.rst | 2 +-
> Documentation/s390/vfio-ccw.rst | 2 +-
> drivers/gpu/drm/i915/gvt/gvt.h | 2 +
> drivers/gpu/drm/i915/gvt/kvmgt.c | 5 +-
> drivers/s390/cio/cio.h | 2 +
> drivers/s390/cio/vfio_ccw_ops.c | 6 +-
> drivers/s390/crypto/vfio_ap_ops.c | 5 +-
> drivers/s390/crypto/vfio_ap_private.h | 1 +
> drivers/vfio/mdev/mdev_core.c | 120 ++++--------------
> drivers/vfio/mdev/mdev_private.h | 23 ----
> drivers/vfio/mdev/mdev_sysfs.c | 4 +-
> include/linux/mdev.h | 15 ++-
> samples/vfio-mdev/mbochs.c | 5 +-
> samples/vfio-mdev/mdpy.c | 5 +-
> samples/vfio-mdev/mtty.c | 6 +-
> 16 files changed, 69 insertions(+), 146 deletions(-)
>
> diff --git a/Documentation/driver-api/vfio-mediated-device.rst b/Documentation/driver-api/vfio-mediated-device.rst
> index 1c57815619fdf..62a82afce161b 100644
> --- a/Documentation/driver-api/vfio-mediated-device.rst
> +++ b/Documentation/driver-api/vfio-mediated-device.rst
> @@ -60,19 +60,19 @@ devices as examples, as these devices are the first devices to use this module::
> | MDEV CORE |
> | MODULE |
> | mdev.ko |
> - | +-----------+ | mdev_register_device() +--------------+
> + | +-----------+ | mdev_register_parent() +--------------+
> | | | +<------------------------+ |
> | | | | | nvidia.ko |<-> physical
> | | | +------------------------>+ | device
> | | | | callbacks +--------------+
> | | Physical | |
> - | | device | | mdev_register_device() +--------------+
> + | | device | | mdev_register_parent() +--------------+
> | | interface | |<------------------------+ |
> | | | | | i915.ko |<-> physical
> | | | +------------------------>+ | device
> | | | | callbacks +--------------+
> | | | |
> - | | | | mdev_register_device() +--------------+
> + | | | | mdev_register_parent() +--------------+
> | | | +<------------------------+ |
> | | | | | ccw_device.ko|<-> physical
> | | | +------------------------>+ | device
> @@ -127,8 +127,8 @@ vfio_device_ops.
> When a driver wants to add the GUID creation sysfs to an existing device it has
> probe'd to then it should call::
>
> - int mdev_register_device(struct device *dev,
> - struct mdev_driver *mdev_driver);
> + int mdev_register_parent(struct mdev_parent *parent, struct device *dev,
> + struct mdev_driver *mdev_driver);
>
> This will provide the 'mdev_supported_types/XX/create' files which can then be
> used to trigger the creation of a mdev_device. The created mdev_device will be
> @@ -136,7 +136,7 @@ attached to the specified driver.
>
> When the driver needs to remove itself it calls::
>
> - void mdev_unregister_device(struct device *dev);
> + void mdev_unregister_parent(struct mdev_parent *parent);
>
> Which will unbind and destroy all the created mdevs and remove the sysfs files.
>
> diff --git a/Documentation/s390/vfio-ap.rst b/Documentation/s390/vfio-ap.rst
> index f57ae621f33e8..37e16158c7fbf 100644
> --- a/Documentation/s390/vfio-ap.rst
> +++ b/Documentation/s390/vfio-ap.rst
> @@ -299,7 +299,7 @@ of the VFIO AP mediated matrix device driver::
> | MDEV CORE |
> | MODULE |
> | mdev.ko |
> - | +---------+ | mdev_register_device() +--------------+
> + | +---------+ | mdev_register_parent() +--------------+
> | |Physical | +<-----------------------+ |
> | | device | | | vfio_ap.ko |<-> matrix
> | |interface| +----------------------->+ | device
> diff --git a/Documentation/s390/vfio-ccw.rst b/Documentation/s390/vfio-ccw.rst
> index 8aad08a8b8a50..ea928a3806f43 100644
> --- a/Documentation/s390/vfio-ccw.rst
> +++ b/Documentation/s390/vfio-ccw.rst
> @@ -156,7 +156,7 @@ Below is a high Level block diagram::
> | MDEV CORE |
> | MODULE |
> | mdev.ko |
> - | +---------+ | mdev_register_device() +--------------+
> + | +---------+ | mdev_register_parent() +--------------+
> | |Physical | +<-----------------------+ |
> | | device | | | vfio_ccw.ko |<-> subchannel
> | |interface| +----------------------->+ | device
> diff --git a/drivers/gpu/drm/i915/gvt/gvt.h b/drivers/gpu/drm/i915/gvt/gvt.h
> index 392c2ad49d376..bbf0116671ecb 100644
> --- a/drivers/gpu/drm/i915/gvt/gvt.h
> +++ b/drivers/gpu/drm/i915/gvt/gvt.h
> @@ -36,6 +36,7 @@
> #include <uapi/linux/pci_regs.h>
> #include <linux/kvm_host.h>
> #include <linux/vfio.h>
> +#include <linux/mdev.h>
>
> #include "i915_drv.h"
> #include "intel_gvt.h"
> @@ -338,6 +339,7 @@ struct intel_gvt {
> struct intel_gvt_workload_scheduler scheduler;
> struct notifier_block shadow_ctx_notifier_block[I915_NUM_ENGINES];
> DECLARE_HASHTABLE(cmd_table, GVT_CMD_HASH_BITS);
> + struct mdev_parent parent;
> struct intel_vgpu_type *types;
> unsigned int num_types;
> struct intel_vgpu *idle_vgpu;
> diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
> index 85e1393d8e55c..e9dba4c0fe6b5 100644
> --- a/drivers/gpu/drm/i915/gvt/kvmgt.c
> +++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
> @@ -1958,7 +1958,7 @@ static void intel_gvt_clean_device(struct drm_i915_private *i915)
> if (drm_WARN_ON(&i915->drm, !gvt))
> return;
>
> - mdev_unregister_device(i915->drm.dev);
> + mdev_unregister_parent(&gvt->parent);
> intel_gvt_cleanup_vgpu_type_groups(gvt);
> intel_gvt_destroy_idle_vgpu(gvt->idle_vgpu);
> intel_gvt_clean_vgpu_types(gvt);
> @@ -2063,7 +2063,8 @@ static int intel_gvt_init_device(struct drm_i915_private *i915)
> if (ret)
> goto out_destroy_idle_vgpu;
>
> - ret = mdev_register_device(i915->drm.dev, &intel_vgpu_mdev_driver);
> + ret = mdev_register_parent(&gvt->parent, i915->drm.dev,
> + &intel_vgpu_mdev_driver);
> if (ret)
> goto out_cleanup_vgpu_type_groups;
>
> diff --git a/drivers/s390/cio/cio.h b/drivers/s390/cio/cio.h
> index fa8df50bb49e3..22be5ac7d23c1 100644
> --- a/drivers/s390/cio/cio.h
> +++ b/drivers/s390/cio/cio.h
> @@ -5,6 +5,7 @@
> #include <linux/mutex.h>
> #include <linux/device.h>
> #include <linux/mod_devicetable.h>
> +#include <linux/mdev.h>
> #include <asm/chpid.h>
> #include <asm/cio.h>
> #include <asm/fcx.h>
> @@ -108,6 +109,7 @@ struct subchannel {
> * frees it. Use driver_set_override() to set or clear it.
> */
> const char *driver_override;
> + struct mdev_parent parent;
> } __attribute__ ((aligned(8)));
>
> DECLARE_PER_CPU_ALIGNED(struct irb, cio_irb);
> diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c
> index b49e2e9db2dc6..9192a21085ce4 100644
> --- a/drivers/s390/cio/vfio_ccw_ops.c
> +++ b/drivers/s390/cio/vfio_ccw_ops.c
> @@ -11,7 +11,6 @@
> */
>
> #include <linux/vfio.h>
> -#include <linux/mdev.h>
> #include <linux/nospec.h>
> #include <linux/slab.h>
>
> @@ -660,10 +659,11 @@ struct mdev_driver vfio_ccw_mdev_driver = {
>
> int vfio_ccw_mdev_reg(struct subchannel *sch)
> {
> - return mdev_register_device(&sch->dev, &vfio_ccw_mdev_driver);
> + return mdev_register_parent(&sch->parent, &sch->dev,
> + &vfio_ccw_mdev_driver);
> }
>
> void vfio_ccw_mdev_unreg(struct subchannel *sch)
> {
> - mdev_unregister_device(&sch->dev);
> + mdev_unregister_parent(&sch->parent);
> }
> diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
> index a7d2a95796d36..834945150dc9f 100644
> --- a/drivers/s390/crypto/vfio_ap_ops.c
> +++ b/drivers/s390/crypto/vfio_ap_ops.c
> @@ -1485,7 +1485,8 @@ int vfio_ap_mdev_register(void)
> if (ret)
> return ret;
>
> - ret = mdev_register_device(&matrix_dev->device, &vfio_ap_matrix_driver);
> + ret = mdev_register_parent(&matrix_dev->parent, &matrix_dev->device,
> + &vfio_ap_matrix_driver);
> if (ret)
> goto err_driver;
> return 0;
> @@ -1497,6 +1498,6 @@ int vfio_ap_mdev_register(void)
>
> void vfio_ap_mdev_unregister(void)
> {
> - mdev_unregister_device(&matrix_dev->device);
> + mdev_unregister_parent(&matrix_dev->parent);
> mdev_unregister_driver(&vfio_ap_matrix_driver);
> }
> diff --git a/drivers/s390/crypto/vfio_ap_private.h b/drivers/s390/crypto/vfio_ap_private.h
> index 6616aa83347ad..0191f6bc973a4 100644
> --- a/drivers/s390/crypto/vfio_ap_private.h
> +++ b/drivers/s390/crypto/vfio_ap_private.h
> @@ -45,6 +45,7 @@ struct ap_matrix_dev {
> struct list_head mdev_list;
> struct mutex lock;
> struct ap_driver *vfio_ap_drv;
> + struct mdev_parent parent;
> };
>
> extern struct ap_matrix_dev *matrix_dev;
> diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c
> index 2c32923fbad27..fa05ac3396950 100644
> --- a/drivers/vfio/mdev/mdev_core.c
> +++ b/drivers/vfio/mdev/mdev_core.c
> @@ -18,8 +18,6 @@
> #define DRIVER_AUTHOR "NVIDIA Corporation"
> #define DRIVER_DESC "Mediated device Core Driver"
>
> -static LIST_HEAD(parent_list);
> -static DEFINE_MUTEX(parent_list_lock);
> static struct class_compat *mdev_bus_compat_class;
>
> static LIST_HEAD(mdev_list);
> @@ -61,28 +59,6 @@ struct device *mtype_get_parent_dev(struct mdev_type *mtype)
> }
> EXPORT_SYMBOL(mtype_get_parent_dev);
>
> -/* Should be called holding parent_list_lock */
> -static struct mdev_parent *__find_parent_device(struct device *dev)
> -{
> - struct mdev_parent *parent;
> -
> - list_for_each_entry(parent, &parent_list, next) {
> - if (parent->dev == dev)
> - return parent;
> - }
> - return NULL;
> -}
> -
> -void mdev_release_parent(struct kref *kref)
> -{
> - struct mdev_parent *parent = container_of(kref, struct mdev_parent,
> - ref);
> - struct device *dev = parent->dev;
> -
> - kfree(parent);
> - put_device(dev);
> -}
> -
> /* Caller must hold parent unreg_sem read or write lock */
> static void mdev_device_remove_common(struct mdev_device *mdev)
> {
> @@ -105,125 +81,73 @@ static int mdev_device_remove_cb(struct device *dev, void *data)
> }
>
> /*
> - * mdev_register_device : Register a device
> + * mdev_register_parent: Register a device as parent for mdevs
> + * @parent: parent structure registered
> * @dev: device structure representing parent device.
> * @mdev_driver: Device driver to bind to the newly created mdev
> *
> - * Add device to list of registered parent devices.
> + * Registers the @parent stucture as a parent for mdev types and thus mdev
> + * devices. The caller needs to hold a reference on @dev that must not be
> + * released until after the call to mdev_unregister_parent().
> + *
> * Returns a negative value on error, otherwise 0.
> */
> -int mdev_register_device(struct device *dev, struct mdev_driver *mdev_driver)
> +int mdev_register_parent(struct mdev_parent *parent, struct device *dev,
> + struct mdev_driver *mdev_driver)
> {
> - int ret;
> - struct mdev_parent *parent;
> char *env_string = "MDEV_STATE=registered";
> char *envp[] = { env_string, NULL };
> + int ret;
>
> /* check for mandatory ops */
> if (!mdev_driver->supported_type_groups)
> return -EINVAL;
>
> - dev = get_device(dev);
> - if (!dev)
> - return -EINVAL;
> -
> - mutex_lock(&parent_list_lock);
> -
> - /* Check for duplicate */
> - parent = __find_parent_device(dev);
> - if (parent) {
> - parent = NULL;
> - ret = -EEXIST;
> - goto add_dev_err;
> - }
> -
> - parent = kzalloc(sizeof(*parent), GFP_KERNEL);
> - if (!parent) {
> - ret = -ENOMEM;
> - goto add_dev_err;
> - }
> -
> - kref_init(&parent->ref);
> + memset(parent, 0, sizeof(*parent));
> init_rwsem(&parent->unreg_sem);
> -
> parent->dev = dev;
> parent->mdev_driver = mdev_driver;
>
> if (!mdev_bus_compat_class) {
> mdev_bus_compat_class = class_compat_register("mdev_bus");
> - if (!mdev_bus_compat_class) {
> - ret = -ENOMEM;
> - goto add_dev_err;
> - }
> + if (!mdev_bus_compat_class)
> + return -ENOMEM;
> }
>
> ret = parent_create_sysfs_files(parent);
> if (ret)
> - goto add_dev_err;
> + return ret;
>
> ret = class_compat_create_link(mdev_bus_compat_class, dev, NULL);
> if (ret)
> dev_warn(dev, "Failed to create compatibility class link\n");
>
> - list_add(&parent->next, &parent_list);
> - mutex_unlock(&parent_list_lock);
> -
> dev_info(dev, "MDEV: Registered\n");
> kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
> -
> return 0;
> -
> -add_dev_err:
> - mutex_unlock(&parent_list_lock);
> - if (parent)
> - mdev_put_parent(parent);
> - else
> - put_device(dev);
> - return ret;
> }
> -EXPORT_SYMBOL(mdev_register_device);
> +EXPORT_SYMBOL(mdev_register_parent);
>
> /*
> - * mdev_unregister_device : Unregister a parent device
> - * @dev: device structure representing parent device.
> - *
> - * Remove device from list of registered parent devices. Give a chance to free
> - * existing mediated devices for given device.
> + * mdev_unregister_parent : Unregister a parent device
> + * @parent: parent structure to unregister
> */
> -
> -void mdev_unregister_device(struct device *dev)
> +void mdev_unregister_parent(struct mdev_parent *parent)
> {
> - struct mdev_parent *parent;
> char *env_string = "MDEV_STATE=unregistered";
> char *envp[] = { env_string, NULL };
>
> - mutex_lock(&parent_list_lock);
> - parent = __find_parent_device(dev);
> -
> - if (!parent) {
> - mutex_unlock(&parent_list_lock);
> - return;
> - }
> - dev_info(dev, "MDEV: Unregistering\n");
> -
> - list_del(&parent->next);
> - mutex_unlock(&parent_list_lock);
> + dev_info(parent->dev, "MDEV: Unregistering\n");
>
> down_write(&parent->unreg_sem);
> -
> - class_compat_remove_link(mdev_bus_compat_class, dev, NULL);
> -
> - device_for_each_child(dev, NULL, mdev_device_remove_cb);
> -
> + class_compat_remove_link(mdev_bus_compat_class, parent->dev, NULL);
> + device_for_each_child(parent->dev, NULL, mdev_device_remove_cb);
> parent_remove_sysfs_files(parent);
> up_write(&parent->unreg_sem);
>
> - mdev_put_parent(parent);
> -
> - /* We still have the caller's reference to use for the uevent */
> - kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
> + kobject_uevent_env(&parent->dev->kobj, KOBJ_CHANGE, envp);
> }
> -EXPORT_SYMBOL(mdev_unregister_device);
> +EXPORT_SYMBOL(mdev_unregister_parent);
>
> static void mdev_device_release(struct device *dev)
> {
> diff --git a/drivers/vfio/mdev/mdev_private.h b/drivers/vfio/mdev/mdev_private.h
> index 7c9fc79f3d838..297f911fdc890 100644
> --- a/drivers/vfio/mdev/mdev_private.h
> +++ b/drivers/vfio/mdev/mdev_private.h
> @@ -13,17 +13,6 @@
> int mdev_bus_register(void);
> void mdev_bus_unregister(void);
>
> -struct mdev_parent {
> - struct device *dev;
> - struct mdev_driver *mdev_driver;
> - struct kref ref;
> - struct list_head next;
> - struct kset *mdev_types_kset;
> - struct list_head type_list;
> - /* Synchronize device creation/removal with parent unregistration */
> - struct rw_semaphore unreg_sem;
> -};
> -
> struct mdev_type {
> struct kobject kobj;
> struct kobject *devices_kobj;
> @@ -48,16 +37,4 @@ void mdev_remove_sysfs_files(struct mdev_device *mdev);
> int mdev_device_create(struct mdev_type *kobj, const guid_t *uuid);
> int mdev_device_remove(struct mdev_device *dev);
>
> -void mdev_release_parent(struct kref *kref);
> -
> -static inline void mdev_get_parent(struct mdev_parent *parent)
> -{
> - kref_get(&parent->ref);
> -}
> -
> -static inline void mdev_put_parent(struct mdev_parent *parent)
> -{
> - kref_put(&parent->ref, mdev_release_parent);
> -}
> -
> #endif /* MDEV_PRIVATE_H */
> diff --git a/drivers/vfio/mdev/mdev_sysfs.c b/drivers/vfio/mdev/mdev_sysfs.c
> index 4bfbf49aaa66a..b71ffc5594870 100644
> --- a/drivers/vfio/mdev/mdev_sysfs.c
> +++ b/drivers/vfio/mdev/mdev_sysfs.c
> @@ -81,7 +81,7 @@ static void mdev_type_release(struct kobject *kobj)
>
> pr_debug("Releasing group %s\n", kobj->name);
> /* Pairs with the get in add_mdev_supported_type() */
> - mdev_put_parent(type->parent);
> + put_device(type->parent->dev);
> kfree(type);
> }
>
> @@ -110,7 +110,7 @@ static struct mdev_type *add_mdev_supported_type(struct mdev_parent *parent,
> type->kobj.kset = parent->mdev_types_kset;
> type->parent = parent;
> /* Pairs with the put in mdev_type_release() */
> - mdev_get_parent(parent);
> + get_device(parent->dev);
> type->type_group_id = type_group_id;
>
> ret = kobject_init_and_add(&type->kobj, &mdev_type_ktype, NULL,
> diff --git a/include/linux/mdev.h b/include/linux/mdev.h
> index 555c1d015b5f0..327ce3e5c6b5f 100644
> --- a/include/linux/mdev.h
> +++ b/include/linux/mdev.h
> @@ -23,6 +23,16 @@ struct mdev_device {
> bool active;
> };
>
> +/* embedded into the struct device that the mdev devices hang off */
> +struct mdev_parent {
> + struct device *dev;
> + struct mdev_driver *mdev_driver;
> + struct kset *mdev_types_kset;
> + struct list_head type_list;
> + /* Synchronize device creation/removal with parent unregistration */
> + struct rw_semaphore unreg_sem;
> +};
> +
> static inline struct mdev_device *to_mdev_device(struct device *dev)
> {
> return container_of(dev, struct mdev_device, dev);
> @@ -75,8 +85,9 @@ static inline const guid_t *mdev_uuid(struct mdev_device *mdev)
>
> extern struct bus_type mdev_bus_type;
>
> -int mdev_register_device(struct device *dev, struct mdev_driver *mdev_driver);
> -void mdev_unregister_device(struct device *dev);
> +int mdev_register_parent(struct mdev_parent *parent, struct device *dev,
> + struct mdev_driver *mdev_driver);
> +void mdev_unregister_parent(struct mdev_parent *parent);
>
> int mdev_register_driver(struct mdev_driver *drv);
> void mdev_unregister_driver(struct mdev_driver *drv);
> diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c
> index d0d1bb7747240..30b3643b3b389 100644
> --- a/samples/vfio-mdev/mbochs.c
> +++ b/samples/vfio-mdev/mbochs.c
> @@ -128,6 +128,7 @@ static dev_t mbochs_devt;
> static struct class *mbochs_class;
> static struct cdev mbochs_cdev;
> static struct device mbochs_dev;
> +static struct mdev_parent mbochs_parent;
> static atomic_t mbochs_avail_mbytes;
> static const struct vfio_device_ops mbochs_dev_ops;
>
> @@ -1456,7 +1457,7 @@ static int __init mbochs_dev_init(void)
> if (ret)
> goto err_class;
>
> - ret = mdev_register_device(&mbochs_dev, &mbochs_driver);
> + ret = mdev_register_parent(&mbochs_parent, &mbochs_dev, &mbochs_driver);
> if (ret)
> goto err_device;
>
> @@ -1477,7 +1478,7 @@ static int __init mbochs_dev_init(void)
> static void __exit mbochs_dev_exit(void)
> {
> mbochs_dev.bus = NULL;
> - mdev_unregister_device(&mbochs_dev);
> + mdev_unregister_parent(&mbochs_parent);
>
> device_unregister(&mbochs_dev);
> mdev_unregister_driver(&mbochs_driver);
> diff --git a/samples/vfio-mdev/mdpy.c b/samples/vfio-mdev/mdpy.c
> index 0c4ca1f4be7ed..132bb055628a6 100644
> --- a/samples/vfio-mdev/mdpy.c
> +++ b/samples/vfio-mdev/mdpy.c
> @@ -83,6 +83,7 @@ static dev_t mdpy_devt;
> static struct class *mdpy_class;
> static struct cdev mdpy_cdev;
> static struct device mdpy_dev;
> +static struct mdev_parent mdpy_parent;
> static u32 mdpy_count;
> static const struct vfio_device_ops mdpy_dev_ops;
>
> @@ -765,7 +766,7 @@ static int __init mdpy_dev_init(void)
> if (ret)
> goto err_class;
>
> - ret = mdev_register_device(&mdpy_dev, &mdpy_driver);
> + ret = mdev_register_parent(&mdpy_parent, &mdpy_dev, &mdpy_driver);
> if (ret)
> goto err_device;
>
> @@ -786,7 +787,7 @@ static int __init mdpy_dev_init(void)
> static void __exit mdpy_dev_exit(void)
> {
> mdpy_dev.bus = NULL;
> - mdev_unregister_device(&mdpy_dev);
> + mdev_unregister_parent(&mdpy_parent);
>
> device_unregister(&mdpy_dev);
> mdev_unregister_driver(&mdpy_driver);
> diff --git a/samples/vfio-mdev/mtty.c b/samples/vfio-mdev/mtty.c
> index 4f5a6f2d3629d..8ba5f6084a093 100644
> --- a/samples/vfio-mdev/mtty.c
> +++ b/samples/vfio-mdev/mtty.c
> @@ -72,6 +72,7 @@ static struct mtty_dev {
> struct cdev vd_cdev;
> struct idr vd_idr;
> struct device dev;
> + struct mdev_parent parent;
> } mtty_dev;
>
> struct mdev_region_info {
> @@ -1350,7 +1351,8 @@ static int __init mtty_dev_init(void)
> if (ret)
> goto err_class;
>
> - ret = mdev_register_device(&mtty_dev.dev, &mtty_driver);
> + ret = mdev_register_parent(&mtty_dev.parent, &mtty_dev.dev,
> + &mtty_driver);
> if (ret)
> goto err_device;
> return 0;
> @@ -1370,7 +1372,7 @@ static int __init mtty_dev_init(void)
> static void __exit mtty_dev_exit(void)
> {
> mtty_dev.dev.bus = NULL;
> - mdev_unregister_device(&mtty_dev.dev);
> + mdev_unregister_parent(&mtty_dev.parent);
>
> device_unregister(&mtty_dev.dev);
> idr_destroy(&mtty_dev.vd_idr);
^ permalink raw reply [flat|nested] 31+ messages in thread
* Re: [PATCH 05/15] vfio/mdev: simplify mdev_type handling
2022-07-06 7:42 ` [PATCH 05/15] vfio/mdev: simplify mdev_type handling Christoph Hellwig
@ 2022-07-06 13:31 ` Kirti Wankhede
0 siblings, 0 replies; 31+ messages in thread
From: Kirti Wankhede @ 2022-07-06 13:31 UTC (permalink / raw)
To: Christoph Hellwig, Tony Krowiak, Halil Pasic, Jason Herne,
Eric Farman, Matthew Rosato, Zhenyu Wang, Zhi Wang,
Alex Williamson
Cc: Jason Gunthorpe, kvm, linux-s390, intel-gvt-dev, Kevin Tian,
Tarun Gupta, Neo Jia, Shounak Deshpande
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
On 7/6/2022 1:12 PM, Christoph Hellwig wrote:
> Instead of abusing struct attribute_group to control initialization of
> struct mdev_type, just define the actual attributes in the mdev_driver,
> allocate the mdev_type structures in the caller and pass them to
> mdev_register_parent.
>
> This allows the caller to use container_of to get at the containing
> structure and thus significantly simplify the code.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
> Reviewed-by: Kevin Tian <kevin.tian@intel.com>
> ---
> .../driver-api/vfio-mediated-device.rst | 2 +-
> drivers/gpu/drm/i915/gvt/gvt.h | 3 +-
> drivers/gpu/drm/i915/gvt/kvmgt.c | 98 +++----------------
> drivers/gpu/drm/i915/gvt/vgpu.c | 13 ++-
> drivers/s390/cio/cio.h | 2 +
> drivers/s390/cio/vfio_ccw_ops.c | 19 ++--
> drivers/s390/crypto/vfio_ap_ops.c | 19 ++--
> drivers/s390/crypto/vfio_ap_private.h | 2 +
> drivers/vfio/mdev/mdev_core.c | 31 ++----
> drivers/vfio/mdev/mdev_driver.c | 5 +-
> drivers/vfio/mdev/mdev_private.h | 8 --
> drivers/vfio/mdev/mdev_sysfs.c | 90 +++++------------
> include/linux/mdev.h | 26 +++--
> samples/vfio-mdev/mbochs.c | 57 +++++------
> samples/vfio-mdev/mdpy.c | 50 ++++------
> samples/vfio-mdev/mtty.c | 62 ++++++------
> 16 files changed, 165 insertions(+), 322 deletions(-)
>
> diff --git a/Documentation/driver-api/vfio-mediated-device.rst b/Documentation/driver-api/vfio-mediated-device.rst
> index 62a82afce161b..82a4007bd7207 100644
> --- a/Documentation/driver-api/vfio-mediated-device.rst
> +++ b/Documentation/driver-api/vfio-mediated-device.rst
> @@ -105,7 +105,7 @@ structure to represent a mediated device's driver::
> struct mdev_driver {
> int (*probe) (struct mdev_device *dev);
> void (*remove) (struct mdev_device *dev);
> - struct attribute_group **supported_type_groups;
> + const struct attribute * const *types_attrs;
> struct device_driver driver;
> };
>
> diff --git a/drivers/gpu/drm/i915/gvt/gvt.h b/drivers/gpu/drm/i915/gvt/gvt.h
> index bbf0116671ecb..f9690dca0a857 100644
> --- a/drivers/gpu/drm/i915/gvt/gvt.h
> +++ b/drivers/gpu/drm/i915/gvt/gvt.h
> @@ -311,8 +311,8 @@ struct intel_vgpu_config {
> const char *name;
> };
>
> -#define NR_MAX_INTEL_VGPU_TYPES 20
> struct intel_vgpu_type {
> + struct mdev_type type;
> char name[16];
> const struct intel_vgpu_config *conf;
> unsigned int avail_instance;
> @@ -340,6 +340,7 @@ struct intel_gvt {
> struct notifier_block shadow_ctx_notifier_block[I915_NUM_ENGINES];
> DECLARE_HASHTABLE(cmd_table, GVT_CMD_HASH_BITS);
> struct mdev_parent parent;
> + struct mdev_type **mdev_types;
> struct intel_vgpu_type *types;
> unsigned int num_types;
> struct intel_vgpu *idle_vgpu;
> diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
> index e9dba4c0fe6b5..ead56e4d30650 100644
> --- a/drivers/gpu/drm/i915/gvt/kvmgt.c
> +++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
> @@ -117,17 +117,10 @@ static ssize_t available_instances_show(struct mdev_type *mtype,
> struct mdev_type_attribute *attr,
> char *buf)
> {
> - struct intel_vgpu_type *type;
> - unsigned int num = 0;
> - struct intel_gvt *gvt = kdev_to_i915(mtype_get_parent_dev(mtype))->gvt;
> + struct intel_vgpu_type *type =
> + container_of(mtype, struct intel_vgpu_type, type);
>
> - type = &gvt->types[mtype_get_type_group_id(mtype)];
> - if (!type)
> - num = 0;
> - else
> - num = type->avail_instance;
> -
> - return sprintf(buf, "%u\n", num);
> + return sprintf(buf, "%u\n", type->avail_instance);
> }
>
> static ssize_t device_api_show(struct mdev_type *mtype,
> @@ -139,12 +132,8 @@ static ssize_t device_api_show(struct mdev_type *mtype,
> static ssize_t description_show(struct mdev_type *mtype,
> struct mdev_type_attribute *attr, char *buf)
> {
> - struct intel_vgpu_type *type;
> - struct intel_gvt *gvt = kdev_to_i915(mtype_get_parent_dev(mtype))->gvt;
> -
> - type = &gvt->types[mtype_get_type_group_id(mtype)];
> - if (!type)
> - return 0;
> + struct intel_vgpu_type *type =
> + container_of(mtype, struct intel_vgpu_type, type);
>
> return sprintf(buf, "low_gm_size: %dMB\nhigh_gm_size: %dMB\n"
> "fence: %d\nresolution: %s\n"
> @@ -158,14 +147,7 @@ static ssize_t description_show(struct mdev_type *mtype,
> static ssize_t name_show(struct mdev_type *mtype,
> struct mdev_type_attribute *attr, char *buf)
> {
> - struct intel_vgpu_type *type;
> - struct intel_gvt *gvt = kdev_to_i915(mtype_get_parent_dev(mtype))->gvt;
> -
> - type = &gvt->types[mtype_get_type_group_id(mtype)];
> - if (!type)
> - return 0;
> -
> - return sprintf(buf, "%s\n", type->name);
> + return sprintf(buf, "%s\n", mtype->sysfs_name);
> }
>
> static MDEV_TYPE_ATTR_RO(available_instances);
> @@ -173,7 +155,7 @@ static MDEV_TYPE_ATTR_RO(device_api);
> static MDEV_TYPE_ATTR_RO(description);
> static MDEV_TYPE_ATTR_RO(name);
>
> -static struct attribute *gvt_type_attrs[] = {
> +static const struct attribute *gvt_type_attrs[] = {
> &mdev_type_attr_available_instances.attr,
> &mdev_type_attr_device_api.attr,
> &mdev_type_attr_description.attr,
> @@ -181,51 +163,6 @@ static struct attribute *gvt_type_attrs[] = {
> NULL,
> };
>
> -static struct attribute_group *gvt_vgpu_type_groups[] = {
> - [0 ... NR_MAX_INTEL_VGPU_TYPES - 1] = NULL,
> -};
> -
> -static int intel_gvt_init_vgpu_type_groups(struct intel_gvt *gvt)
> -{
> - int i, j;
> - struct intel_vgpu_type *type;
> - struct attribute_group *group;
> -
> - for (i = 0; i < gvt->num_types; i++) {
> - type = &gvt->types[i];
> -
> - group = kzalloc(sizeof(struct attribute_group), GFP_KERNEL);
> - if (!group)
> - goto unwind;
> -
> - group->name = type->name;
> - group->attrs = gvt_type_attrs;
> - gvt_vgpu_type_groups[i] = group;
> - }
> -
> - return 0;
> -
> -unwind:
> - for (j = 0; j < i; j++) {
> - group = gvt_vgpu_type_groups[j];
> - kfree(group);
> - }
> -
> - return -ENOMEM;
> -}
> -
> -static void intel_gvt_cleanup_vgpu_type_groups(struct intel_gvt *gvt)
> -{
> - int i;
> - struct attribute_group *group;
> -
> - for (i = 0; i < gvt->num_types; i++) {
> - group = gvt_vgpu_type_groups[i];
> - gvt_vgpu_type_groups[i] = NULL;
> - kfree(group);
> - }
> -}
> -
> static void gvt_unpin_guest_page(struct intel_vgpu *vgpu, unsigned long gfn,
> unsigned long size)
> {
> @@ -1614,14 +1551,11 @@ static int intel_vgpu_probe(struct mdev_device *mdev)
> {
> struct device *pdev = mdev_parent_dev(mdev);
> struct intel_gvt *gvt = kdev_to_i915(pdev)->gvt;
> - struct intel_vgpu_type *type;
> + struct intel_vgpu_type *type =
> + container_of(mdev->type, struct intel_vgpu_type, type);
> struct intel_vgpu *vgpu;
> int ret;
>
> - type = &gvt->types[mdev_get_type_group_id(mdev)];
> - if (!type)
> - return -EINVAL;
> -
> vgpu = intel_gvt_create_vgpu(gvt, type->conf);
> if (IS_ERR(vgpu)) {
> gvt_err("failed to create intel vgpu: %ld\n", PTR_ERR(vgpu));
> @@ -1660,7 +1594,7 @@ static struct mdev_driver intel_vgpu_mdev_driver = {
> },
> .probe = intel_vgpu_probe,
> .remove = intel_vgpu_remove,
> - .supported_type_groups = gvt_vgpu_type_groups,
> + .types_attrs = gvt_type_attrs,
> };
>
> int intel_gvt_page_track_add(struct intel_vgpu *info, u64 gfn)
> @@ -1959,7 +1893,6 @@ static void intel_gvt_clean_device(struct drm_i915_private *i915)
> return;
>
> mdev_unregister_parent(&gvt->parent);
> - intel_gvt_cleanup_vgpu_type_groups(gvt);
> intel_gvt_destroy_idle_vgpu(gvt->idle_vgpu);
> intel_gvt_clean_vgpu_types(gvt);
>
> @@ -2059,20 +1992,15 @@ static int intel_gvt_init_device(struct drm_i915_private *i915)
>
> intel_gvt_debugfs_init(gvt);
>
> - ret = intel_gvt_init_vgpu_type_groups(gvt);
> - if (ret)
> - goto out_destroy_idle_vgpu;
> -
> ret = mdev_register_parent(&gvt->parent, i915->drm.dev,
> - &intel_vgpu_mdev_driver);
> + &intel_vgpu_mdev_driver,
> + gvt->mdev_types, gvt->num_types);
> if (ret)
> - goto out_cleanup_vgpu_type_groups;
> + goto out_destroy_idle_vgpu;
>
> gvt_dbg_core("gvt device initialization is done\n");
> return 0;
>
> -out_cleanup_vgpu_type_groups:
> - intel_gvt_cleanup_vgpu_type_groups(gvt);
> out_destroy_idle_vgpu:
> intel_gvt_destroy_idle_vgpu(gvt->idle_vgpu);
> intel_gvt_debugfs_clean(gvt);
> diff --git a/drivers/gpu/drm/i915/gvt/vgpu.c b/drivers/gpu/drm/i915/gvt/vgpu.c
> index 8e136dcc70112..ff240503d4125 100644
> --- a/drivers/gpu/drm/i915/gvt/vgpu.c
> +++ b/drivers/gpu/drm/i915/gvt/vgpu.c
> @@ -113,13 +113,18 @@ int intel_gvt_init_vgpu_types(struct intel_gvt *gvt)
> if (!gvt->types)
> return -ENOMEM;
>
> + gvt->mdev_types = kcalloc(num_types, sizeof(*gvt->mdev_types),
> + GFP_KERNEL);
> + if (!gvt->mdev_types)
> + goto out_free_types;
> +
> for (i = 0; i < num_types; ++i) {
> const struct intel_vgpu_config *conf = &intel_vgpu_configs[i];
>
> if (low_avail / conf->low_mm == 0)
> break;
> if (conf->weight < 1 || conf->weight > VGPU_MAX_WEIGHT)
> - goto out_free_types;
> + goto out_free_mdev_types;
>
> sprintf(gvt->types[i].name, "GVTg_V%u_%s",
> GRAPHICS_VER(gvt->gt->i915) == 8 ? 4 : 5, conf->name);
> @@ -131,11 +136,16 @@ int intel_gvt_init_vgpu_types(struct intel_gvt *gvt)
> i, gvt->types[i].name, gvt->types[i].avail_instance,
> conf->low_mm, conf->high_mm, conf->fence,
> conf->weight, vgpu_edid_str(conf->edid));
> +
> + gvt->mdev_types[i] = &gvt->types[i].type;
> + gvt->mdev_types[i]->sysfs_name = gvt->types[i].name;
> }
>
> gvt->num_types = i;
> return 0;
>
> +out_free_mdev_types:
> + kfree(gvt->mdev_types);
> out_free_types:
> kfree(gvt->types);
> return -EINVAL;
> @@ -143,6 +153,7 @@ int intel_gvt_init_vgpu_types(struct intel_gvt *gvt)
>
> void intel_gvt_clean_vgpu_types(struct intel_gvt *gvt)
> {
> + kfree(gvt->mdev_types);
> kfree(gvt->types);
> }
>
> diff --git a/drivers/s390/cio/cio.h b/drivers/s390/cio/cio.h
> index 22be5ac7d23c1..1da45307a1862 100644
> --- a/drivers/s390/cio/cio.h
> +++ b/drivers/s390/cio/cio.h
> @@ -110,6 +110,8 @@ struct subchannel {
> */
> const char *driver_override;
> struct mdev_parent parent;
> + struct mdev_type mdev_type;
> + struct mdev_type *mdev_types[1];
> } __attribute__ ((aligned(8)));
>
> DECLARE_PER_CPU_ALIGNED(struct irb, cio_irb);
> diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c
> index 9192a21085ce4..1bb30313a630c 100644
> --- a/drivers/s390/cio/vfio_ccw_ops.c
> +++ b/drivers/s390/cio/vfio_ccw_ops.c
> @@ -95,23 +95,13 @@ static ssize_t available_instances_show(struct mdev_type *mtype,
> }
> static MDEV_TYPE_ATTR_RO(available_instances);
>
> -static struct attribute *mdev_types_attrs[] = {
> +static const struct attribute *mdev_types_attrs[] = {
> &mdev_type_attr_name.attr,
> &mdev_type_attr_device_api.attr,
> &mdev_type_attr_available_instances.attr,
> NULL,
> };
>
> -static struct attribute_group mdev_type_group = {
> - .name = "io",
> - .attrs = mdev_types_attrs,
> -};
> -
> -static struct attribute_group *mdev_type_groups[] = {
> - &mdev_type_group,
> - NULL,
> -};
> -
> static int vfio_ccw_mdev_probe(struct mdev_device *mdev)
> {
> struct vfio_ccw_private *private = dev_get_drvdata(mdev->dev.parent);
> @@ -654,13 +644,16 @@ struct mdev_driver vfio_ccw_mdev_driver = {
> },
> .probe = vfio_ccw_mdev_probe,
> .remove = vfio_ccw_mdev_remove,
> - .supported_type_groups = mdev_type_groups,
> + .types_attrs = mdev_types_attrs,
> };
>
> int vfio_ccw_mdev_reg(struct subchannel *sch)
> {
> + sch->mdev_type.sysfs_name = "io";
> + sch->mdev_types[0] = &sch->mdev_type;
> return mdev_register_parent(&sch->parent, &sch->dev,
> - &vfio_ccw_mdev_driver);
> + &vfio_ccw_mdev_driver, sch->mdev_types,
> + 1);
> }
>
> void vfio_ccw_mdev_unreg(struct subchannel *sch)
> diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
> index 834945150dc9f..41e8ecb7f56b9 100644
> --- a/drivers/s390/crypto/vfio_ap_ops.c
> +++ b/drivers/s390/crypto/vfio_ap_ops.c
> @@ -537,23 +537,13 @@ static ssize_t device_api_show(struct mdev_type *mtype,
>
> static MDEV_TYPE_ATTR_RO(device_api);
>
> -static struct attribute *vfio_ap_mdev_type_attrs[] = {
> +static const struct attribute *vfio_ap_mdev_type_attrs[] = {
> &mdev_type_attr_name.attr,
> &mdev_type_attr_device_api.attr,
> &mdev_type_attr_available_instances.attr,
> NULL,
> };
>
> -static struct attribute_group vfio_ap_mdev_hwvirt_type_group = {
> - .name = VFIO_AP_MDEV_TYPE_HWVIRT,
> - .attrs = vfio_ap_mdev_type_attrs,
> -};
> -
> -static struct attribute_group *vfio_ap_mdev_type_groups[] = {
> - &vfio_ap_mdev_hwvirt_type_group,
> - NULL,
> -};
> -
> struct vfio_ap_queue_reserved {
> unsigned long *apid;
> unsigned long *apqi;
> @@ -1472,7 +1462,7 @@ static struct mdev_driver vfio_ap_matrix_driver = {
> },
> .probe = vfio_ap_mdev_probe,
> .remove = vfio_ap_mdev_remove,
> - .supported_type_groups = vfio_ap_mdev_type_groups,
> + .types_attrs = vfio_ap_mdev_type_attrs,
> };
>
> int vfio_ap_mdev_register(void)
> @@ -1485,8 +1475,11 @@ int vfio_ap_mdev_register(void)
> if (ret)
> return ret;
>
> + matrix_dev->mdev_type.sysfs_name = VFIO_AP_MDEV_TYPE_HWVIRT;
> + matrix_dev->mdev_types[0] = &matrix_dev->mdev_type;
> ret = mdev_register_parent(&matrix_dev->parent, &matrix_dev->device,
> - &vfio_ap_matrix_driver);
> + &vfio_ap_matrix_driver,
> + matrix_dev->mdev_types, 1);
> if (ret)
> goto err_driver;
> return 0;
> diff --git a/drivers/s390/crypto/vfio_ap_private.h b/drivers/s390/crypto/vfio_ap_private.h
> index 0191f6bc973a4..5dc5050d03791 100644
> --- a/drivers/s390/crypto/vfio_ap_private.h
> +++ b/drivers/s390/crypto/vfio_ap_private.h
> @@ -46,6 +46,8 @@ struct ap_matrix_dev {
> struct mutex lock;
> struct ap_driver *vfio_ap_drv;
> struct mdev_parent parent;
> + struct mdev_type mdev_type;
> + struct mdev_type *mdev_types[];
> };
>
> extern struct ap_matrix_dev *matrix_dev;
> diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c
> index fa05ac3396950..2d95a497fd3b2 100644
> --- a/drivers/vfio/mdev/mdev_core.c
> +++ b/drivers/vfio/mdev/mdev_core.c
> @@ -29,26 +29,6 @@ struct device *mdev_parent_dev(struct mdev_device *mdev)
> }
> EXPORT_SYMBOL(mdev_parent_dev);
>
> -/*
> - * Return the index in supported_type_groups that this mdev_device was created
> - * from.
> - */
> -unsigned int mdev_get_type_group_id(struct mdev_device *mdev)
> -{
> - return mdev->type->type_group_id;
> -}
> -EXPORT_SYMBOL(mdev_get_type_group_id);
> -
> -/*
> - * Used in mdev_type_attribute sysfs functions to return the index in the
> - * supported_type_groups that the sysfs is called from.
> - */
> -unsigned int mtype_get_type_group_id(struct mdev_type *mtype)
> -{
> - return mtype->type_group_id;
> -}
> -EXPORT_SYMBOL(mtype_get_type_group_id);
> -
> /*
> * Used in mdev_type_attribute sysfs functions to return the parent struct
> * device
> @@ -85,6 +65,8 @@ static int mdev_device_remove_cb(struct device *dev, void *data)
> * @parent: parent structure registered
> * @dev: device structure representing parent device.
> * @mdev_driver: Device driver to bind to the newly created mdev
> + * @types: Array of supported mdev types
> + * @nr_types: Number of entries in @types
> *
> * Registers the @parent stucture as a parent for mdev types and thus mdev
> * devices. The caller needs to hold a reference on @dev that must not be
> @@ -93,20 +75,19 @@ static int mdev_device_remove_cb(struct device *dev, void *data)
> * Returns a negative value on error, otherwise 0.
> */
> int mdev_register_parent(struct mdev_parent *parent, struct device *dev,
> - struct mdev_driver *mdev_driver)
> + struct mdev_driver *mdev_driver, struct mdev_type **types,
> + unsigned int nr_types)
> {
> char *env_string = "MDEV_STATE=registered";
> char *envp[] = { env_string, NULL };
> int ret;
>
> - /* check for mandatory ops */
> - if (!mdev_driver->supported_type_groups)
> - return -EINVAL;
> -
> memset(parent, 0, sizeof(*parent));
> init_rwsem(&parent->unreg_sem);
> parent->dev = dev;
> parent->mdev_driver = mdev_driver;
> + parent->types = types;
> + parent->nr_types = nr_types;
>
> if (!mdev_bus_compat_class) {
> mdev_bus_compat_class = class_compat_register("mdev_bus");
> diff --git a/drivers/vfio/mdev/mdev_driver.c b/drivers/vfio/mdev/mdev_driver.c
> index 7bd4bb9850e81..1da1ecf76a0d5 100644
> --- a/drivers/vfio/mdev/mdev_driver.c
> +++ b/drivers/vfio/mdev/mdev_driver.c
> @@ -56,10 +56,9 @@ EXPORT_SYMBOL_GPL(mdev_bus_type);
> **/
> int mdev_register_driver(struct mdev_driver *drv)
> {
> - /* initialize common driver fields */
> + if (!drv->types_attrs)
> + return -EINVAL;
> drv->driver.bus = &mdev_bus_type;
> -
> - /* register with core */
> return driver_register(&drv->driver);
> }
> EXPORT_SYMBOL(mdev_register_driver);
> diff --git a/drivers/vfio/mdev/mdev_private.h b/drivers/vfio/mdev/mdev_private.h
> index 297f911fdc890..ba1b2dbddc0bc 100644
> --- a/drivers/vfio/mdev/mdev_private.h
> +++ b/drivers/vfio/mdev/mdev_private.h
> @@ -13,14 +13,6 @@
> int mdev_bus_register(void);
> void mdev_bus_unregister(void);
>
> -struct mdev_type {
> - struct kobject kobj;
> - struct kobject *devices_kobj;
> - struct mdev_parent *parent;
> - struct list_head next;
> - unsigned int type_group_id;
> -};
> -
> extern const struct attribute_group *mdev_device_groups[];
>
> #define to_mdev_type_attr(_attr) \
> diff --git a/drivers/vfio/mdev/mdev_sysfs.c b/drivers/vfio/mdev/mdev_sysfs.c
> index b71ffc5594870..80b2d546a3d98 100644
> --- a/drivers/vfio/mdev/mdev_sysfs.c
> +++ b/drivers/vfio/mdev/mdev_sysfs.c
> @@ -90,35 +90,21 @@ static struct kobj_type mdev_type_ktype = {
> .release = mdev_type_release,
> };
>
> -static struct mdev_type *add_mdev_supported_type(struct mdev_parent *parent,
> - unsigned int type_group_id)
> +static int mdev_type_add(struct mdev_parent *parent, struct mdev_type *type)
> {
> - struct mdev_type *type;
> - struct attribute_group *group =
> - parent->mdev_driver->supported_type_groups[type_group_id];
> int ret;
>
> - if (!group->name) {
> - pr_err("%s: Type name empty!\n", __func__);
> - return ERR_PTR(-EINVAL);
> - }
> -
> - type = kzalloc(sizeof(*type), GFP_KERNEL);
> - if (!type)
> - return ERR_PTR(-ENOMEM);
> -
> type->kobj.kset = parent->mdev_types_kset;
> type->parent = parent;
> /* Pairs with the put in mdev_type_release() */
> get_device(parent->dev);
> - type->type_group_id = type_group_id;
>
> ret = kobject_init_and_add(&type->kobj, &mdev_type_ktype, NULL,
> "%s-%s", dev_driver_string(parent->dev),
> - group->name);
> + type->sysfs_name);
> if (ret) {
> kobject_put(&type->kobj);
> - return ERR_PTR(ret);
> + return ret;
> }
>
> ret = sysfs_create_file(&type->kobj, &mdev_type_attr_create.attr);
> @@ -131,13 +117,10 @@ static struct mdev_type *add_mdev_supported_type(struct mdev_parent *parent,
> goto attr_devices_failed;
> }
>
> - ret = sysfs_create_files(&type->kobj,
> - (const struct attribute **)group->attrs);
> - if (ret) {
> - ret = -ENOMEM;
> + ret = sysfs_create_files(&type->kobj, parent->mdev_driver->types_attrs);
> + if (ret)
> goto attrs_failed;
> - }
> - return type;
> + return 0;
>
> attrs_failed:
> kobject_put(type->devices_kobj);
> @@ -146,78 +129,49 @@ static struct mdev_type *add_mdev_supported_type(struct mdev_parent *parent,
> attr_create_failed:
> kobject_del(&type->kobj);
> kobject_put(&type->kobj);
> - return ERR_PTR(ret);
> + return ret;
> }
>
> -static void remove_mdev_supported_type(struct mdev_type *type)
> +static void mdev_type_remove(struct mdev_type *type)
> {
> - struct attribute_group *group =
> - type->parent->mdev_driver->supported_type_groups[type->type_group_id];
> + sysfs_remove_files(&type->kobj, type->parent->mdev_driver->types_attrs);
>
> - sysfs_remove_files(&type->kobj,
> - (const struct attribute **)group->attrs);
> kobject_put(type->devices_kobj);
> sysfs_remove_file(&type->kobj, &mdev_type_attr_create.attr);
> kobject_del(&type->kobj);
> kobject_put(&type->kobj);
> }
>
> -static int add_mdev_supported_type_groups(struct mdev_parent *parent)
> -{
> - int i;
> -
> - for (i = 0; parent->mdev_driver->supported_type_groups[i]; i++) {
> - struct mdev_type *type;
> -
> - type = add_mdev_supported_type(parent, i);
> - if (IS_ERR(type)) {
> - struct mdev_type *ltype, *tmp;
> -
> - list_for_each_entry_safe(ltype, tmp, &parent->type_list,
> - next) {
> - list_del(<ype->next);
> - remove_mdev_supported_type(ltype);
> - }
> - return PTR_ERR(type);
> - }
> - list_add(&type->next, &parent->type_list);
> - }
> - return 0;
> -}
> -
> /* mdev sysfs functions */
> void parent_remove_sysfs_files(struct mdev_parent *parent)
> {
> - struct mdev_type *type, *tmp;
> -
> - list_for_each_entry_safe(type, tmp, &parent->type_list, next) {
> - list_del(&type->next);
> - remove_mdev_supported_type(type);
> - }
> + int i;
>
> + for (i = 0; i < parent->nr_types; i++)
> + mdev_type_remove(parent->types[i]);
> kset_unregister(parent->mdev_types_kset);
> }
>
> int parent_create_sysfs_files(struct mdev_parent *parent)
> {
> - int ret;
> + int ret, i;
>
> parent->mdev_types_kset = kset_create_and_add("mdev_supported_types",
> NULL, &parent->dev->kobj);
> -
> if (!parent->mdev_types_kset)
> return -ENOMEM;
>
> - INIT_LIST_HEAD(&parent->type_list);
> -
> - ret = add_mdev_supported_type_groups(parent);
> - if (ret)
> - goto create_err;
> + for (i = 0; i < parent->nr_types; i++) {
> + ret = mdev_type_add(parent, parent->types[i]);
> + if (ret)
> + goto out_err;
> + }
> return 0;
>
> -create_err:
> - kset_unregister(parent->mdev_types_kset);
> - return ret;
> +out_err:
> + while (--i >= 0)
> + mdev_type_remove(parent->types[i]);
> + return 0;
> }
>
> static ssize_t remove_store(struct device *dev, struct device_attribute *attr,
> diff --git a/include/linux/mdev.h b/include/linux/mdev.h
> index 327ce3e5c6b5f..cc70cc1e25d91 100644
> --- a/include/linux/mdev.h
> +++ b/include/linux/mdev.h
> @@ -23,14 +23,27 @@ struct mdev_device {
> bool active;
> };
>
> +struct mdev_type {
> + /* set by the driver before calling mdev_register parent: */
> + const char *sysfs_name;
> +
> + /* set by the core, can be used drivers */
> + struct mdev_parent *parent;
> +
> + /* internal only */
> + struct kobject kobj;
> + struct kobject *devices_kobj;
> +};
> +
> /* embedded into the struct device that the mdev devices hang off */
> struct mdev_parent {
> struct device *dev;
> struct mdev_driver *mdev_driver;
> struct kset *mdev_types_kset;
> - struct list_head type_list;
> /* Synchronize device creation/removal with parent unregistration */
> struct rw_semaphore unreg_sem;
> + struct mdev_type **types;
> + unsigned int nr_types;
> };
>
> static inline struct mdev_device *to_mdev_device(struct device *dev)
> @@ -38,8 +51,6 @@ static inline struct mdev_device *to_mdev_device(struct device *dev)
> return container_of(dev, struct mdev_device, dev);
> }
>
> -unsigned int mdev_get_type_group_id(struct mdev_device *mdev);
> -unsigned int mtype_get_type_group_id(struct mdev_type *mtype);
> struct device *mtype_get_parent_dev(struct mdev_type *mtype);
>
> /* interface for exporting mdev supported type attributes */
> @@ -66,15 +77,13 @@ struct mdev_type_attribute mdev_type_attr_##_name = \
> * struct mdev_driver - Mediated device driver
> * @probe: called when new device created
> * @remove: called when device removed
> - * @supported_type_groups: Attributes to define supported types. It is mandatory
> - * to provide supported types.
> + * @types_attrs: attributes to the type kobjects.
> * @driver: device driver structure
> - *
> **/
> struct mdev_driver {
> int (*probe)(struct mdev_device *dev);
> void (*remove)(struct mdev_device *dev);
> - struct attribute_group **supported_type_groups;
> + const struct attribute * const *types_attrs;
> struct device_driver driver;
> };
>
> @@ -86,7 +95,8 @@ static inline const guid_t *mdev_uuid(struct mdev_device *mdev)
> extern struct bus_type mdev_bus_type;
>
> int mdev_register_parent(struct mdev_parent *parent, struct device *dev,
> - struct mdev_driver *mdev_driver);
> + struct mdev_driver *mdev_driver, struct mdev_type **types,
> + unsigned int nr_types);
> void mdev_unregister_parent(struct mdev_parent *parent);
>
> int mdev_register_driver(struct mdev_driver *drv);
> diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c
> index 30b3643b3b389..1069f561cb012 100644
> --- a/samples/vfio-mdev/mbochs.c
> +++ b/samples/vfio-mdev/mbochs.c
> @@ -99,23 +99,27 @@ MODULE_PARM_DESC(mem, "megabytes available to " MBOCHS_NAME " devices");
> #define MBOCHS_TYPE_2 "medium"
> #define MBOCHS_TYPE_3 "large"
>
> -static const struct mbochs_type {
> +static struct mbochs_type {
> + struct mdev_type type;
> const char *name;
> u32 mbytes;
> u32 max_x;
> u32 max_y;
> } mbochs_types[] = {
> {
> + .type.sysfs_name = MBOCHS_TYPE_1,
> .name = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_1,
> .mbytes = 4,
> .max_x = 800,
> .max_y = 600,
> }, {
> + .type.sysfs_name = MBOCHS_TYPE_2,
> .name = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_2,
> .mbytes = 16,
> .max_x = 1920,
> .max_y = 1440,
> }, {
> + .type.sysfs_name = MBOCHS_TYPE_3,
> .name = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_3,
> .mbytes = 64,
> .max_x = 0,
> @@ -123,6 +127,11 @@ static const struct mbochs_type {
> },
> };
>
> +static struct mdev_type *mbochs_mdev_types[] = {
> + &mbochs_types[0].type,
> + &mbochs_types[1].type,
> + &mbochs_types[2].type,
> +};
>
> static dev_t mbochs_devt;
> static struct class *mbochs_class;
> @@ -508,8 +517,8 @@ static int mbochs_reset(struct mdev_state *mdev_state)
> static int mbochs_probe(struct mdev_device *mdev)
> {
> int avail_mbytes = atomic_read(&mbochs_avail_mbytes);
> - const struct mbochs_type *type =
> - &mbochs_types[mdev_get_type_group_id(mdev)];
> + struct mbochs_type *type =
> + container_of(mdev->type, struct mbochs_type, type);
> struct device *dev = mdev_dev(mdev);
> struct mdev_state *mdev_state;
> int ret = -ENOMEM;
> @@ -1328,8 +1337,8 @@ static const struct attribute_group *mdev_dev_groups[] = {
> static ssize_t name_show(struct mdev_type *mtype,
> struct mdev_type_attribute *attr, char *buf)
> {
> - const struct mbochs_type *type =
> - &mbochs_types[mtype_get_type_group_id(mtype)];
> + struct mbochs_type *type =
> + container_of(mtype, struct mbochs_type, type);
>
> return sprintf(buf, "%s\n", type->name);
> }
> @@ -1338,8 +1347,8 @@ static MDEV_TYPE_ATTR_RO(name);
> static ssize_t description_show(struct mdev_type *mtype,
> struct mdev_type_attribute *attr, char *buf)
> {
> - const struct mbochs_type *type =
> - &mbochs_types[mtype_get_type_group_id(mtype)];
> + struct mbochs_type *type =
> + container_of(mtype, struct mbochs_type, type);
>
> return sprintf(buf, "virtual display, %d MB video memory\n",
> type ? type->mbytes : 0);
> @@ -1350,8 +1359,8 @@ static ssize_t available_instances_show(struct mdev_type *mtype,
> struct mdev_type_attribute *attr,
> char *buf)
> {
> - const struct mbochs_type *type =
> - &mbochs_types[mtype_get_type_group_id(mtype)];
> + struct mbochs_type *type =
> + container_of(mtype, struct mbochs_type, type);
> int count = atomic_read(&mbochs_avail_mbytes) / type->mbytes;
>
> return sprintf(buf, "%d\n", count);
> @@ -1365,7 +1374,7 @@ static ssize_t device_api_show(struct mdev_type *mtype,
> }
> static MDEV_TYPE_ATTR_RO(device_api);
>
> -static struct attribute *mdev_types_attrs[] = {
> +static const struct attribute *mdev_types_attrs[] = {
> &mdev_type_attr_name.attr,
> &mdev_type_attr_description.attr,
> &mdev_type_attr_device_api.attr,
> @@ -1373,28 +1382,6 @@ static struct attribute *mdev_types_attrs[] = {
> NULL,
> };
>
> -static struct attribute_group mdev_type_group1 = {
> - .name = MBOCHS_TYPE_1,
> - .attrs = mdev_types_attrs,
> -};
> -
> -static struct attribute_group mdev_type_group2 = {
> - .name = MBOCHS_TYPE_2,
> - .attrs = mdev_types_attrs,
> -};
> -
> -static struct attribute_group mdev_type_group3 = {
> - .name = MBOCHS_TYPE_3,
> - .attrs = mdev_types_attrs,
> -};
> -
> -static struct attribute_group *mdev_type_groups[] = {
> - &mdev_type_group1,
> - &mdev_type_group2,
> - &mdev_type_group3,
> - NULL,
> -};
> -
> static const struct vfio_device_ops mbochs_dev_ops = {
> .close_device = mbochs_close_device,
> .read = mbochs_read,
> @@ -1412,7 +1399,7 @@ static struct mdev_driver mbochs_driver = {
> },
> .probe = mbochs_probe,
> .remove = mbochs_remove,
> - .supported_type_groups = mdev_type_groups,
> + .types_attrs = mdev_types_attrs,
> };
>
> static const struct file_operations vd_fops = {
> @@ -1457,7 +1444,9 @@ static int __init mbochs_dev_init(void)
> if (ret)
> goto err_class;
>
> - ret = mdev_register_parent(&mbochs_parent, &mbochs_dev, &mbochs_driver);
> + ret = mdev_register_parent(&mbochs_parent, &mbochs_dev, &mbochs_driver,
> + mbochs_mdev_types,
> + ARRAY_SIZE(mbochs_mdev_types));
> if (ret)
> goto err_device;
>
> diff --git a/samples/vfio-mdev/mdpy.c b/samples/vfio-mdev/mdpy.c
> index 132bb055628a6..2052cc27b1c6d 100644
> --- a/samples/vfio-mdev/mdpy.c
> +++ b/samples/vfio-mdev/mdpy.c
> @@ -51,7 +51,8 @@ MODULE_PARM_DESC(count, "number of " MDPY_NAME " devices");
> #define MDPY_TYPE_2 "xga"
> #define MDPY_TYPE_3 "hd"
>
> -static const struct mdpy_type {
> +static struct mdpy_type {
> + struct mdev_type type;
> const char *name;
> u32 format;
> u32 bytepp;
> @@ -59,18 +60,21 @@ static const struct mdpy_type {
> u32 height;
> } mdpy_types[] = {
> {
> + .type.sysfs_name = MDPY_TYPE_1,
> .name = MDPY_CLASS_NAME "-" MDPY_TYPE_1,
> .format = DRM_FORMAT_XRGB8888,
> .bytepp = 4,
> .width = 640,
> .height = 480,
> }, {
> + .type.sysfs_name = MDPY_TYPE_2,
> .name = MDPY_CLASS_NAME "-" MDPY_TYPE_2,
> .format = DRM_FORMAT_XRGB8888,
> .bytepp = 4,
> .width = 1024,
> .height = 768,
> }, {
> + .type.sysfs_name = MDPY_TYPE_3,
> .name = MDPY_CLASS_NAME "-" MDPY_TYPE_3,
> .format = DRM_FORMAT_XRGB8888,
> .bytepp = 4,
> @@ -79,6 +83,12 @@ static const struct mdpy_type {
> },
> };
>
> +static struct mdev_type *mdpy_mdev_types[] = {
> + &mdpy_types[0].type,
> + &mdpy_types[1].type,
> + &mdpy_types[2].type,
> +};
> +
> static dev_t mdpy_devt;
> static struct class *mdpy_class;
> static struct cdev mdpy_cdev;
> @@ -219,7 +229,7 @@ static int mdpy_reset(struct mdev_state *mdev_state)
> static int mdpy_probe(struct mdev_device *mdev)
> {
> const struct mdpy_type *type =
> - &mdpy_types[mdev_get_type_group_id(mdev)];
> + container_of(mdev->type, struct mdpy_type, type);
> struct device *dev = mdev_dev(mdev);
> struct mdev_state *mdev_state;
> u32 fbsize;
> @@ -644,8 +654,7 @@ static const struct attribute_group *mdev_dev_groups[] = {
> static ssize_t name_show(struct mdev_type *mtype,
> struct mdev_type_attribute *attr, char *buf)
> {
> - const struct mdpy_type *type =
> - &mdpy_types[mtype_get_type_group_id(mtype)];
> + struct mdpy_type *type = container_of(mtype, struct mdpy_type, type);
>
> return sprintf(buf, "%s\n", type->name);
> }
> @@ -654,8 +663,7 @@ static MDEV_TYPE_ATTR_RO(name);
> static ssize_t description_show(struct mdev_type *mtype,
> struct mdev_type_attribute *attr, char *buf)
> {
> - const struct mdpy_type *type =
> - &mdpy_types[mtype_get_type_group_id(mtype)];
> + struct mdpy_type *type = container_of(mtype, struct mdpy_type, type);
>
> return sprintf(buf, "virtual display, %dx%d framebuffer\n",
> type->width, type->height);
> @@ -677,7 +685,7 @@ static ssize_t device_api_show(struct mdev_type *mtype,
> }
> static MDEV_TYPE_ATTR_RO(device_api);
>
> -static struct attribute *mdev_types_attrs[] = {
> +static const struct attribute *mdev_types_attrs[] = {
> &mdev_type_attr_name.attr,
> &mdev_type_attr_description.attr,
> &mdev_type_attr_device_api.attr,
> @@ -685,28 +693,6 @@ static struct attribute *mdev_types_attrs[] = {
> NULL,
> };
>
> -static struct attribute_group mdev_type_group1 = {
> - .name = MDPY_TYPE_1,
> - .attrs = mdev_types_attrs,
> -};
> -
> -static struct attribute_group mdev_type_group2 = {
> - .name = MDPY_TYPE_2,
> - .attrs = mdev_types_attrs,
> -};
> -
> -static struct attribute_group mdev_type_group3 = {
> - .name = MDPY_TYPE_3,
> - .attrs = mdev_types_attrs,
> -};
> -
> -static struct attribute_group *mdev_type_groups[] = {
> - &mdev_type_group1,
> - &mdev_type_group2,
> - &mdev_type_group3,
> - NULL,
> -};
> -
> static const struct vfio_device_ops mdpy_dev_ops = {
> .read = mdpy_read,
> .write = mdpy_write,
> @@ -723,7 +709,7 @@ static struct mdev_driver mdpy_driver = {
> },
> .probe = mdpy_probe,
> .remove = mdpy_remove,
> - .supported_type_groups = mdev_type_groups,
> + .types_attrs = mdev_types_attrs,
> };
>
> static const struct file_operations vd_fops = {
> @@ -766,7 +752,9 @@ static int __init mdpy_dev_init(void)
> if (ret)
> goto err_class;
>
> - ret = mdev_register_parent(&mdpy_parent, &mdpy_dev, &mdpy_driver);
> + ret = mdev_register_parent(&mdpy_parent, &mdpy_dev, &mdpy_driver,
> + mdpy_mdev_types,
> + ARRAY_SIZE(mdpy_mdev_types));
> if (ret)
> goto err_device;
>
> diff --git a/samples/vfio-mdev/mtty.c b/samples/vfio-mdev/mtty.c
> index 8ba5f6084a093..029a19ef8ce7b 100644
> --- a/samples/vfio-mdev/mtty.c
> +++ b/samples/vfio-mdev/mtty.c
> @@ -143,6 +143,20 @@ struct mdev_state {
> int nr_ports;
> };
>
> +static struct mtty_type {
> + struct mdev_type type;
> + int nr_ports;
> + const char *name;
> +} mtty_types[2] = {
> + { .nr_ports = 1, .type.sysfs_name = "1", .name = "Single port serial" },
> + { .nr_ports = 2, .type.sysfs_name = "2", .name = "Dual port serial" },
> +};
> +
> +static struct mdev_type *mtty_mdev_types[] = {
> + &mtty_types[0].type,
> + &mtty_types[1].type,
> +};
> +
> static atomic_t mdev_avail_ports = ATOMIC_INIT(MAX_MTTYS);
>
> static const struct file_operations vd_fops = {
> @@ -704,16 +718,18 @@ static ssize_t mdev_access(struct mdev_state *mdev_state, u8 *buf, size_t count,
>
> static int mtty_probe(struct mdev_device *mdev)
> {
> + struct mtty_type *type =
> + container_of(mdev->type, struct mtty_type, type);
> struct mdev_state *mdev_state;
> - int nr_ports = mdev_get_type_group_id(mdev) + 1;
> int avail_ports = atomic_read(&mdev_avail_ports);
> int ret;
>
> do {
> - if (avail_ports < nr_ports)
> + if (avail_ports < type->nr_ports)
> return -ENOSPC;
> } while (!atomic_try_cmpxchg(&mdev_avail_ports,
> - &avail_ports, avail_ports - nr_ports));
> + &avail_ports,
> + avail_ports - type->nr_ports));
>
> mdev_state = kzalloc(sizeof(struct mdev_state), GFP_KERNEL);
> if (mdev_state == NULL) {
> @@ -723,13 +739,13 @@ static int mtty_probe(struct mdev_device *mdev)
>
> vfio_init_group_dev(&mdev_state->vdev, &mdev->dev, &mtty_dev_ops);
>
> - mdev_state->nr_ports = nr_ports;
> + mdev_state->nr_ports = type->nr_ports;
> mdev_state->irq_index = -1;
> mdev_state->s[0].max_fifo_size = MAX_FIFO_SIZE;
> mdev_state->s[1].max_fifo_size = MAX_FIFO_SIZE;
> mutex_init(&mdev_state->rxtx_lock);
> - mdev_state->vconfig = kzalloc(MTTY_CONFIG_SPACE_SIZE, GFP_KERNEL);
>
> + mdev_state->vconfig = kzalloc(MTTY_CONFIG_SPACE_SIZE, GFP_KERNEL);
> if (mdev_state->vconfig == NULL) {
> ret = -ENOMEM;
> goto err_state;
> @@ -752,7 +768,7 @@ static int mtty_probe(struct mdev_device *mdev)
> vfio_uninit_group_dev(&mdev_state->vdev);
> kfree(mdev_state);
> err_nr_ports:
> - atomic_add(nr_ports, &mdev_avail_ports);
> + atomic_add(type->nr_ports, &mdev_avail_ports);
> return ret;
> }
>
> @@ -1233,11 +1249,9 @@ static const struct attribute_group *mdev_dev_groups[] = {
> static ssize_t name_show(struct mdev_type *mtype,
> struct mdev_type_attribute *attr, char *buf)
> {
> - static const char *name_str[2] = { "Single port serial",
> - "Dual port serial" };
> + struct mtty_type *type = container_of(mtype, struct mtty_type, type);
>
> - return sysfs_emit(buf, "%s\n",
> - name_str[mtype_get_type_group_id(mtype)]);
> + return sysfs_emit(buf, "%s\n", type->name);
> }
>
> static MDEV_TYPE_ATTR_RO(name);
> @@ -1246,9 +1260,10 @@ static ssize_t available_instances_show(struct mdev_type *mtype,
> struct mdev_type_attribute *attr,
> char *buf)
> {
> - unsigned int ports = mtype_get_type_group_id(mtype) + 1;
> + struct mtty_type *type = container_of(mtype, struct mtty_type, type);
>
> - return sprintf(buf, "%d\n", atomic_read(&mdev_avail_ports) / ports);
> + return sprintf(buf, "%d\n", atomic_read(&mdev_avail_ports) /
> + type->nr_ports);
> }
>
> static MDEV_TYPE_ATTR_RO(available_instances);
> @@ -1261,29 +1276,13 @@ static ssize_t device_api_show(struct mdev_type *mtype,
>
> static MDEV_TYPE_ATTR_RO(device_api);
>
> -static struct attribute *mdev_types_attrs[] = {
> +static const struct attribute *mdev_types_attrs[] = {
> &mdev_type_attr_name.attr,
> &mdev_type_attr_device_api.attr,
> &mdev_type_attr_available_instances.attr,
> NULL,
> };
>
> -static struct attribute_group mdev_type_group1 = {
> - .name = "1",
> - .attrs = mdev_types_attrs,
> -};
> -
> -static struct attribute_group mdev_type_group2 = {
> - .name = "2",
> - .attrs = mdev_types_attrs,
> -};
> -
> -static struct attribute_group *mdev_type_groups[] = {
> - &mdev_type_group1,
> - &mdev_type_group2,
> - NULL,
> -};
> -
> static const struct vfio_device_ops mtty_dev_ops = {
> .name = "vfio-mtty",
> .read = mtty_read,
> @@ -1300,7 +1299,7 @@ static struct mdev_driver mtty_driver = {
> },
> .probe = mtty_probe,
> .remove = mtty_remove,
> - .supported_type_groups = mdev_type_groups,
> + .types_attrs = mdev_types_attrs,
> };
>
> static void mtty_device_release(struct device *dev)
> @@ -1352,7 +1351,8 @@ static int __init mtty_dev_init(void)
> goto err_class;
>
> ret = mdev_register_parent(&mtty_dev.parent, &mtty_dev.dev,
> - &mtty_driver);
> + &mtty_driver, mtty_mdev_types,
> + ARRAY_SIZE(mtty_mdev_types));
> if (ret)
> goto err_device;
> return 0;
^ permalink raw reply [flat|nested] 31+ messages in thread
* Re: [PATCH 14/15] vfio/mdev: add mdev available instance checking to the core
2022-07-06 7:42 ` [PATCH 14/15] vfio/mdev: add mdev available instance checking to the core Christoph Hellwig
@ 2022-07-06 13:37 ` Kirti Wankhede
2022-07-07 3:08 ` Eric Farman
1 sibling, 0 replies; 31+ messages in thread
From: Kirti Wankhede @ 2022-07-06 13:37 UTC (permalink / raw)
To: Christoph Hellwig, Tony Krowiak, Halil Pasic, Jason Herne,
Eric Farman, Matthew Rosato, Zhenyu Wang, Zhi Wang,
Alex Williamson
Cc: Jason Gunthorpe, kvm, linux-s390, intel-gvt-dev, Kevin Tian,
Tarun Gupta, Neo Jia, Shounak Deshpande
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
On 7/6/2022 1:12 PM, Christoph Hellwig wrote:
> Many of the mdev drivers use a simple counter for keeping track of the
> available instances. Move this code to the core code and store the counter
> in the mdev_parent. Implement it using correct locking, fixing mdpy.
>
> Drivers just provide the value in the mdev_driver at registration time
> and the core code takes care of maintaining it and exposing the value in
> sysfs.
>
> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
> [count instances per-parent instead of per-type]
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> Reviewed-by: Kevin Tian <kevin.tian@intel.com>
> ---
> drivers/s390/cio/vfio_ccw_drv.c | 1 -
> drivers/s390/cio/vfio_ccw_ops.c | 14 +-------------
> drivers/s390/cio/vfio_ccw_private.h | 2 --
> drivers/s390/crypto/vfio_ap_ops.c | 21 +++------------------
> drivers/s390/crypto/vfio_ap_private.h | 2 --
> drivers/vfio/mdev/mdev_core.c | 18 +++++++++++++++---
> include/linux/mdev.h | 3 +++
> samples/vfio-mdev/mdpy.c | 23 ++++-------------------
> 8 files changed, 26 insertions(+), 58 deletions(-)
>
> diff --git a/drivers/s390/cio/vfio_ccw_drv.c b/drivers/s390/cio/vfio_ccw_drv.c
> index 750d0315f1f5b..449c76b29a3b5 100644
> --- a/drivers/s390/cio/vfio_ccw_drv.c
> +++ b/drivers/s390/cio/vfio_ccw_drv.c
> @@ -149,7 +149,6 @@ static struct vfio_ccw_private *vfio_ccw_alloc_private(struct subchannel *sch)
> INIT_LIST_HEAD(&private->crw);
> INIT_WORK(&private->io_work, vfio_ccw_sch_io_todo);
> INIT_WORK(&private->crw_work, vfio_ccw_crw_todo);
> - atomic_set(&private->avail, 1);
>
> private->cp.guest_cp = kcalloc(CCWCHAIN_LEN_MAX, sizeof(struct ccw1),
> GFP_KERNEL);
> diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c
> index 6f6a0f2695059..c05d80add7be2 100644
> --- a/drivers/s390/cio/vfio_ccw_ops.c
> +++ b/drivers/s390/cio/vfio_ccw_ops.c
> @@ -70,13 +70,6 @@ static int vfio_ccw_mdev_notifier(struct notifier_block *nb,
> return NOTIFY_DONE;
> }
>
> -static unsigned int vfio_ccw_get_available(struct mdev_type *mtype)
> -{
> - struct vfio_ccw_private *private = dev_get_drvdata(mtype->parent->dev);
> -
> - return atomic_read(&private->avail);
> -}
> -
> static int vfio_ccw_mdev_probe(struct mdev_device *mdev)
> {
> struct vfio_ccw_private *private = dev_get_drvdata(mdev->dev.parent);
> @@ -85,9 +78,6 @@ static int vfio_ccw_mdev_probe(struct mdev_device *mdev)
> if (private->state == VFIO_CCW_STATE_NOT_OPER)
> return -ENODEV;
>
> - if (atomic_dec_if_positive(&private->avail) < 0)
> - return -EPERM;
> -
> memset(&private->vdev, 0, sizeof(private->vdev));
> vfio_init_group_dev(&private->vdev, &mdev->dev,
> &vfio_ccw_dev_ops);
> @@ -108,7 +98,6 @@ static int vfio_ccw_mdev_probe(struct mdev_device *mdev)
>
> err_atomic:
> vfio_uninit_group_dev(&private->vdev);
> - atomic_inc(&private->avail);
> private->mdev = NULL;
> private->state = VFIO_CCW_STATE_IDLE;
> return ret;
> @@ -135,7 +124,6 @@ static void vfio_ccw_mdev_remove(struct mdev_device *mdev)
> vfio_uninit_group_dev(&private->vdev);
> cp_free(&private->cp);
> private->mdev = NULL;
> - atomic_inc(&private->avail);
> }
>
> static int vfio_ccw_mdev_open_device(struct vfio_device *vdev)
> @@ -613,6 +601,7 @@ static const struct vfio_device_ops vfio_ccw_dev_ops = {
>
> struct mdev_driver vfio_ccw_mdev_driver = {
> .device_api = VFIO_DEVICE_API_CCW_STRING,
> + .max_instances = 1,
> .driver = {
> .name = "vfio_ccw_mdev",
> .owner = THIS_MODULE,
> @@ -620,7 +609,6 @@ struct mdev_driver vfio_ccw_mdev_driver = {
> },
> .probe = vfio_ccw_mdev_probe,
> .remove = vfio_ccw_mdev_remove,
> - .get_available = vfio_ccw_get_available,
> };
>
> int vfio_ccw_mdev_reg(struct subchannel *sch)
> diff --git a/drivers/s390/cio/vfio_ccw_private.h b/drivers/s390/cio/vfio_ccw_private.h
> index b7163bac8cc75..9be5baed0cb7f 100644
> --- a/drivers/s390/cio/vfio_ccw_private.h
> +++ b/drivers/s390/cio/vfio_ccw_private.h
> @@ -72,7 +72,6 @@ struct vfio_ccw_crw {
> * @sch: pointer to the subchannel
> * @state: internal state of the device
> * @completion: synchronization helper of the I/O completion
> - * @avail: available for creating a mediated device
> * @mdev: pointer to the mediated device
> * @nb: notifier for vfio events
> * @io_region: MMIO region to input/output I/O arguments/results
> @@ -96,7 +95,6 @@ struct vfio_ccw_private {
> struct subchannel *sch;
> int state;
> struct completion *completion;
> - atomic_t avail;
> struct mdev_device *mdev;
> struct notifier_block nb;
> struct ccw_io_region *io_region;
> diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
> index edeec11c56560..69ed88fdaf383 100644
> --- a/drivers/s390/crypto/vfio_ap_ops.c
> +++ b/drivers/s390/crypto/vfio_ap_ops.c
> @@ -461,14 +461,9 @@ static int vfio_ap_mdev_probe(struct mdev_device *mdev)
> struct ap_matrix_mdev *matrix_mdev;
> int ret;
>
> - if ((atomic_dec_if_positive(&matrix_dev->available_instances) < 0))
> - return -EPERM;
> -
> matrix_mdev = kzalloc(sizeof(*matrix_mdev), GFP_KERNEL);
> - if (!matrix_mdev) {
> - ret = -ENOMEM;
> - goto err_dec_available;
> - }
> + if (!matrix_mdev)
> + return -ENOMEM;
> vfio_init_group_dev(&matrix_mdev->vdev, &mdev->dev,
> &vfio_ap_matrix_dev_ops);
>
> @@ -491,8 +486,6 @@ static int vfio_ap_mdev_probe(struct mdev_device *mdev)
> mutex_unlock(&matrix_dev->lock);
> vfio_uninit_group_dev(&matrix_mdev->vdev);
> kfree(matrix_mdev);
> -err_dec_available:
> - atomic_inc(&matrix_dev->available_instances);
> return ret;
> }
>
> @@ -508,12 +501,6 @@ static void vfio_ap_mdev_remove(struct mdev_device *mdev)
> mutex_unlock(&matrix_dev->lock);
> vfio_uninit_group_dev(&matrix_mdev->vdev);
> kfree(matrix_mdev);
> - atomic_inc(&matrix_dev->available_instances);
> -}
> -
> -static unsigned int vfio_ap_mdev_get_available(struct mdev_type *mtype)
> -{
> - return atomic_read(&matrix_dev->available_instances);
> }
>
> struct vfio_ap_queue_reserved {
> @@ -1427,6 +1414,7 @@ static const struct vfio_device_ops vfio_ap_matrix_dev_ops = {
>
> static struct mdev_driver vfio_ap_matrix_driver = {
> .device_api = VFIO_DEVICE_API_AP_STRING,
> + .max_instances = MAX_ZDEV_ENTRIES_EXT,
> .driver = {
> .name = "vfio_ap_mdev",
> .owner = THIS_MODULE,
> @@ -1435,15 +1423,12 @@ static struct mdev_driver vfio_ap_matrix_driver = {
> },
> .probe = vfio_ap_mdev_probe,
> .remove = vfio_ap_mdev_remove,
> - .get_available = vfio_ap_mdev_get_available,
> };
>
> int vfio_ap_mdev_register(void)
> {
> int ret;
>
> - atomic_set(&matrix_dev->available_instances, MAX_ZDEV_ENTRIES_EXT);
> -
> ret = mdev_register_driver(&vfio_ap_matrix_driver);
> if (ret)
> return ret;
> diff --git a/drivers/s390/crypto/vfio_ap_private.h b/drivers/s390/crypto/vfio_ap_private.h
> index 5dc5050d03791..b808b343b771f 100644
> --- a/drivers/s390/crypto/vfio_ap_private.h
> +++ b/drivers/s390/crypto/vfio_ap_private.h
> @@ -28,7 +28,6 @@
> * struct ap_matrix_dev - Contains the data for the matrix device.
> *
> * @device: generic device structure associated with the AP matrix device
> - * @available_instances: number of mediated matrix devices that can be created
> * @info: the struct containing the output from the PQAP(QCI) instruction
> * @mdev_list: the list of mediated matrix devices created
> * @lock: mutex for locking the AP matrix device. This lock will be
> @@ -40,7 +39,6 @@
> */
> struct ap_matrix_dev {
> struct device device;
> - atomic_t available_instances;
> struct ap_config_info info;
> struct list_head mdev_list;
> struct mutex lock;
> diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c
> index 93f8caf2e5f77..9bc897235c492 100644
> --- a/drivers/vfio/mdev/mdev_core.c
> +++ b/drivers/vfio/mdev/mdev_core.c
> @@ -70,6 +70,7 @@ int mdev_register_parent(struct mdev_parent *parent, struct device *dev,
> parent->mdev_driver = mdev_driver;
> parent->types = types;
> parent->nr_types = nr_types;
> + parent->available_instances = mdev_driver->max_instances;
>
> if (!mdev_bus_compat_class) {
> mdev_bus_compat_class = class_compat_register("mdev_bus");
> @@ -115,14 +116,17 @@ EXPORT_SYMBOL(mdev_unregister_parent);
> static void mdev_device_release(struct device *dev)
> {
> struct mdev_device *mdev = to_mdev_device(dev);
> -
> - /* Pairs with the get in mdev_device_create() */
> - kobject_put(&mdev->type->kobj);
> + struct mdev_parent *parent = mdev->type->parent;
>
> mutex_lock(&mdev_list_lock);
> list_del(&mdev->next);
> + if (!parent->mdev_driver->get_available)
> + parent->available_instances++;
> mutex_unlock(&mdev_list_lock);
>
> + /* Pairs with the get in mdev_device_create() */
> + kobject_put(&mdev->type->kobj);
> +
> dev_dbg(&mdev->dev, "MDEV: destroying\n");
> kfree(mdev);
> }
> @@ -144,6 +148,14 @@ int mdev_device_create(struct mdev_type *type, const guid_t *uuid)
> }
> }
>
> + if (!drv->get_available) {
> + if (!parent->available_instances) {
> + mutex_unlock(&mdev_list_lock);
> + return -EUSERS;
> + }
> + parent->available_instances--;
> + }
> +
> mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
> if (!mdev) {
> mutex_unlock(&mdev_list_lock);
> diff --git a/include/linux/mdev.h b/include/linux/mdev.h
> index dc38ad2b07883..641ed18a61247 100644
> --- a/include/linux/mdev.h
> +++ b/include/linux/mdev.h
> @@ -45,6 +45,7 @@ struct mdev_parent {
> struct rw_semaphore unreg_sem;
> struct mdev_type **types;
> unsigned int nr_types;
> + unsigned int available_instances;
> };
>
> static inline struct mdev_device *to_mdev_device(struct device *dev)
> @@ -55,6 +56,7 @@ static inline struct mdev_device *to_mdev_device(struct device *dev)
> /**
> * struct mdev_driver - Mediated device driver
> * @device_api: string to return for the device_api sysfs
> + * @max_instances: maximum number of instances supported (optional)
> * @probe: called when new device created
> * @remove: called when device removed
> * @get_available: Return the max number of instances that can be created
> @@ -63,6 +65,7 @@ static inline struct mdev_device *to_mdev_device(struct device *dev)
> **/
> struct mdev_driver {
> const char *device_api;
> + unsigned int max_instances;
> int (*probe)(struct mdev_device *dev);
> void (*remove)(struct mdev_device *dev);
> unsigned int (*get_available)(struct mdev_type *mtype);
> diff --git a/samples/vfio-mdev/mdpy.c b/samples/vfio-mdev/mdpy.c
> index 250b7ea2df2e4..7f7ac5491407e 100644
> --- a/samples/vfio-mdev/mdpy.c
> +++ b/samples/vfio-mdev/mdpy.c
> @@ -42,11 +42,6 @@
>
> MODULE_LICENSE("GPL v2");
>
> -static int max_devices = 4;
> -module_param_named(count, max_devices, int, 0444);
> -MODULE_PARM_DESC(count, "number of " MDPY_NAME " devices");
> -
> -
> #define MDPY_TYPE_1 "vga"
> #define MDPY_TYPE_2 "xga"
> #define MDPY_TYPE_3 "hd"
> @@ -93,7 +88,6 @@ static struct class *mdpy_class;
> static struct cdev mdpy_cdev;
> static struct device mdpy_dev;
> static struct mdev_parent mdpy_parent;
> -static u32 mdpy_count;
> static const struct vfio_device_ops mdpy_dev_ops;
>
> /* State of each mdev device */
> @@ -234,9 +228,6 @@ static int mdpy_probe(struct mdev_device *mdev)
> u32 fbsize;
> int ret;
>
> - if (mdpy_count >= max_devices)
> - return -ENOMEM;
> -
> mdev_state = kzalloc(sizeof(struct mdev_state), GFP_KERNEL);
> if (mdev_state == NULL)
> return -ENOMEM;
> @@ -265,8 +256,6 @@ static int mdpy_probe(struct mdev_device *mdev)
> mdpy_create_config_space(mdev_state);
> mdpy_reset(mdev_state);
>
> - mdpy_count++;
> -
> ret = vfio_register_emulated_iommu_dev(&mdev_state->vdev);
> if (ret)
> goto err_mem;
> @@ -293,8 +282,6 @@ static void mdpy_remove(struct mdev_device *mdev)
> kfree(mdev_state->vconfig);
> vfio_uninit_group_dev(&mdev_state->vdev);
> kfree(mdev_state);
> -
> - mdpy_count--;
> }
>
> static ssize_t mdpy_read(struct vfio_device *vdev, char __user *buf,
> @@ -658,11 +645,6 @@ static ssize_t mdpy_show_description(struct mdev_type *mtype, char *buf)
> type->width, type->height);
> }
>
> -static unsigned int mdpy_get_available(struct mdev_type *mtype)
> -{
> - return max_devices - mdpy_count;
> -}
> -
> static const struct vfio_device_ops mdpy_dev_ops = {
> .read = mdpy_read,
> .write = mdpy_write,
> @@ -672,6 +654,7 @@ static const struct vfio_device_ops mdpy_dev_ops = {
>
> static struct mdev_driver mdpy_driver = {
> .device_api = VFIO_DEVICE_API_PCI_STRING,
> + .max_instances = 4,
> .driver = {
> .name = "mdpy",
> .owner = THIS_MODULE,
> @@ -680,7 +663,6 @@ static struct mdev_driver mdpy_driver = {
> },
> .probe = mdpy_probe,
> .remove = mdpy_remove,
> - .get_available = mdpy_get_available,
> .show_description = mdpy_show_description,
> };
>
> @@ -757,5 +739,8 @@ static void __exit mdpy_dev_exit(void)
> mdpy_class = NULL;
> }
>
> +module_param_named(count, mdpy_driver.max_instances, int, 0444);
> +MODULE_PARM_DESC(count, "number of " MDPY_NAME " devices");
> +
> module_init(mdpy_dev_init)
> module_exit(mdpy_dev_exit)
^ permalink raw reply [flat|nested] 31+ messages in thread
* Re: [PATCH 15/15] vfio/mdev: remove an extra parent kobject reference
2022-07-06 7:42 ` [PATCH 15/15] vfio/mdev: remove an extra parent kobject reference Christoph Hellwig
@ 2022-07-06 13:48 ` Kirti Wankhede
2022-07-07 13:37 ` Christoph Hellwig
2022-07-06 14:38 ` Jason Gunthorpe
2022-07-07 2:19 ` Tian, Kevin
2 siblings, 1 reply; 31+ messages in thread
From: Kirti Wankhede @ 2022-07-06 13:48 UTC (permalink / raw)
To: Christoph Hellwig, Tony Krowiak, Halil Pasic, Jason Herne,
Eric Farman, Matthew Rosato, Zhenyu Wang, Zhi Wang,
Alex Williamson
Cc: Jason Gunthorpe, kvm, linux-s390, intel-gvt-dev, Tarun Gupta,
Neo Jia, Shounak Deshpande
On 7/6/2022 1:12 PM, Christoph Hellwig wrote:
> The mdev_type already holds a reference to the parent through
> mdev_types_kset, so drop the extra reference.
>
> Suggested-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
> drivers/vfio/mdev/mdev_sysfs.c | 9 +--------
> 1 file changed, 1 insertion(+), 8 deletions(-)
>
> diff --git a/drivers/vfio/mdev/mdev_sysfs.c b/drivers/vfio/mdev/mdev_sysfs.c
> index c5cd035d591d0..e2087cac1c859 100644
> --- a/drivers/vfio/mdev/mdev_sysfs.c
> +++ b/drivers/vfio/mdev/mdev_sysfs.c
> @@ -153,8 +153,6 @@ static void mdev_type_release(struct kobject *kobj)
> struct mdev_type *type = to_mdev_type(kobj);
>
> pr_debug("Releasing group %s\n", kobj->name);
> - /* Pairs with the get in add_mdev_supported_type() */
> - put_device(type->parent->dev);
> kfree(type);
> }
>
> @@ -170,16 +168,12 @@ static int mdev_type_add(struct mdev_parent *parent, struct mdev_type *type)
>
> type->kobj.kset = parent->mdev_types_kset;
> type->parent = parent;
> - /* Pairs with the put in mdev_type_release() */
> - get_device(parent->dev);
>
> ret = kobject_init_and_add(&type->kobj, &mdev_type_ktype, NULL,
> "%s-%s", dev_driver_string(parent->dev),
> type->sysfs_name);
> - if (ret) {
> - kobject_put(&type->kobj);
This kobject_put is required here in error case, see description above
kobject_init_and_add().
> + if (ret)
> return ret;
> - }
>
> type->devices_kobj = kobject_create_and_add("devices", &type->kobj);
> if (!type->devices_kobj) {
> @@ -191,7 +185,6 @@ static int mdev_type_add(struct mdev_parent *parent, struct mdev_type *type)
>
> attr_devices_failed:
> kobject_del(&type->kobj);
> - kobject_put(&type->kobj);
Same as above.
Thanks,
Kirti
^ permalink raw reply [flat|nested] 31+ messages in thread
* Re: [PATCH 15/15] vfio/mdev: remove an extra parent kobject reference
2022-07-06 7:42 ` [PATCH 15/15] vfio/mdev: remove an extra parent kobject reference Christoph Hellwig
2022-07-06 13:48 ` Kirti Wankhede
@ 2022-07-06 14:38 ` Jason Gunthorpe
2022-07-07 13:40 ` Christoph Hellwig
2022-07-07 2:19 ` Tian, Kevin
2 siblings, 1 reply; 31+ messages in thread
From: Jason Gunthorpe @ 2022-07-06 14:38 UTC (permalink / raw)
To: Christoph Hellwig
Cc: Kirti Wankhede, Tony Krowiak, Halil Pasic, Jason Herne,
Eric Farman, Matthew Rosato, Zhenyu Wang, Zhi Wang,
Alex Williamson, kvm, linux-s390, intel-gvt-dev
On Wed, Jul 06, 2022 at 09:42:19AM +0200, Christoph Hellwig wrote:
> The mdev_type already holds a reference to the parent through
> mdev_types_kset, so drop the extra reference.
I would drop this patch, but at least the explanation needs tweaking..
kobj's are weird things, they have a kobj.parent, but the refcount for
that is dropped during kobject_del() and parent is NULL'd. vs this
reference which is being put back at kobject release.
So, the extra kset reference isn't contributing more protection - when
mdev_unregister_device() calls kset_unregister() it still has a valid
reference on the parent from the caller.
If this change is safe it is because no accesses to mdev->parent are
happening after mdev_unregister_device() returns, due to things like
the sysfs attribute fencing and the mdev_unreg_sem fencing child
devices. I didn't check everything, but it seems believable it could
be true.
I also suggest this patch should NULL mdev_type->parent during
unregister_device as the kobj stuff does, so any use after unregister
but before release could be crash, we generally shouldn't leave
unref'd pointers floating around.
Jason
^ permalink raw reply [flat|nested] 31+ messages in thread
* RE: [PATCH 02/15] drm/i915/gvt: simplify vgpu configuration management
2022-07-06 7:42 ` [PATCH 02/15] drm/i915/gvt: simplify vgpu configuration management Christoph Hellwig
@ 2022-07-07 2:18 ` Tian, Kevin
0 siblings, 0 replies; 31+ messages in thread
From: Tian, Kevin @ 2022-07-07 2:18 UTC (permalink / raw)
To: Christoph Hellwig, Kirti Wankhede, Tony Krowiak, Halil Pasic,
Jason Herne, Eric Farman, Matthew Rosato, Zhenyu Wang, Wang,
Zhi A, Alex Williamson
Cc: linux-s390, intel-gvt-dev, kvm, Jason Gunthorpe
> From: Christoph Hellwig
> Sent: Wednesday, July 6, 2022 3:42 PM
>
> Instead of copying the information from the vgpu_types arrays into each
> intel_vgpu_type structure, just reference this constant information
> with a pointer to the already existing data structure, and pass it into
> the low-level VGPU creation helpers intead of copying the data into yet
> anothe params data structure.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
> Reviewed-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
^ permalink raw reply [flat|nested] 31+ messages in thread
* RE: [PATCH 15/15] vfio/mdev: remove an extra parent kobject reference
2022-07-06 7:42 ` [PATCH 15/15] vfio/mdev: remove an extra parent kobject reference Christoph Hellwig
2022-07-06 13:48 ` Kirti Wankhede
2022-07-06 14:38 ` Jason Gunthorpe
@ 2022-07-07 2:19 ` Tian, Kevin
2 siblings, 0 replies; 31+ messages in thread
From: Tian, Kevin @ 2022-07-07 2:19 UTC (permalink / raw)
To: Christoph Hellwig, Kirti Wankhede, Tony Krowiak, Halil Pasic,
Jason Herne, Eric Farman, Matthew Rosato, Zhenyu Wang, Wang,
Zhi A, Alex Williamson
Cc: linux-s390, intel-gvt-dev, kvm, Jason Gunthorpe
> From: Christoph Hellwig
> Sent: Wednesday, July 6, 2022 3:42 PM
>
> The mdev_type already holds a reference to the parent through
> mdev_types_kset, so drop the extra reference.
>
> Suggested-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
^ permalink raw reply [flat|nested] 31+ messages in thread
* Re: [PATCH 04/15] vfio/mdev: embedd struct mdev_parent in the parent data structure
2022-07-06 7:42 ` [PATCH 04/15] vfio/mdev: embedd struct mdev_parent in the parent data structure Christoph Hellwig
2022-07-06 13:29 ` Kirti Wankhede
@ 2022-07-07 3:08 ` Eric Farman
2022-07-07 7:22 ` Vineeth Vijayan
1 sibling, 1 reply; 31+ messages in thread
From: Eric Farman @ 2022-07-07 3:08 UTC (permalink / raw)
To: Christoph Hellwig, Kirti Wankhede, Tony Krowiak, Halil Pasic,
Jason Herne, Matthew Rosato, Zhenyu Wang, Zhi Wang,
Alex Williamson, Vineeth Vijayan, Peter Oberparleiter
Cc: Jason Gunthorpe, kvm, linux-s390, intel-gvt-dev, Kevin Tian
On Wed, 2022-07-06 at 09:42 +0200, Christoph Hellwig wrote:
> Simplify mdev_{un}register_device by requiring the caller to pass in
> a structure allocate as part of the parent device structure. This
> removes the need for a list of parents and the separate mdev_parent
> refcount as we can simplify rely on the reference to the parent
> device.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
> Reviewed-by: Kevin Tian <kevin.tian@intel.com>
> ---
> .../driver-api/vfio-mediated-device.rst | 12 +-
> Documentation/s390/vfio-ap.rst | 2 +-
> Documentation/s390/vfio-ccw.rst | 2 +-
> drivers/gpu/drm/i915/gvt/gvt.h | 2 +
> drivers/gpu/drm/i915/gvt/kvmgt.c | 5 +-
> drivers/s390/cio/cio.h | 2 +
> drivers/s390/cio/vfio_ccw_ops.c | 6 +-
(@Vineeth, @Peter FYI regarding struct subchannel)
I haven't had a chance to look at this series with enough focus, but
the change to cio.h (here, and patch 5) caught my eye. I would've
expected the "parent" to be struct vfio_ccw_private, instead of the
subchannel.
Eric
> drivers/s390/crypto/vfio_ap_ops.c | 5 +-
> drivers/s390/crypto/vfio_ap_private.h | 1 +
> drivers/vfio/mdev/mdev_core.c | 120 ++++----------
> ----
> drivers/vfio/mdev/mdev_private.h | 23 ----
> drivers/vfio/mdev/mdev_sysfs.c | 4 +-
> include/linux/mdev.h | 15 ++-
> samples/vfio-mdev/mbochs.c | 5 +-
> samples/vfio-mdev/mdpy.c | 5 +-
> samples/vfio-mdev/mtty.c | 6 +-
> 16 files changed, 69 insertions(+), 146 deletions(-)
>
> diff --git a/Documentation/driver-api/vfio-mediated-device.rst
> b/Documentation/driver-api/vfio-mediated-device.rst
> index 1c57815619fdf..62a82afce161b 100644
> --- a/Documentation/driver-api/vfio-mediated-device.rst
> +++ b/Documentation/driver-api/vfio-mediated-device.rst
> @@ -60,19 +60,19 @@ devices as examples, as these devices are the
> first devices to use this module::
> | MDEV CORE |
> | MODULE |
> | mdev.ko |
> - | +-----------+ | mdev_register_device() +--------------+
> + | +-----------+ | mdev_register_parent() +--------------+
> | | | +<------------------------+ |
> | | | | | nvidia.ko |<->
> physical
> | | | +----------------------
> -->+ | device
> | | | | callbacks +--------------+
> | | Physical | |
> - | | device | | mdev_register_device() +--------------+
> + | | device | | mdev_register_parent() +--------------+
> | | interface | |<------------------------+ |
> | | | | | i915.ko |<->
> physical
> | | | +----------------------
> -->+ | device
> | | | | callbacks +--------------+
> | | | |
> - | | | | mdev_register_device() +--------------+
> + | | | | mdev_register_parent() +--------------+
> | | | +<------------------------+ |
> | | | | | ccw_device.ko|<->
> physical
> | | | +----------------------
> -->+ | device
> @@ -127,8 +127,8 @@ vfio_device_ops.
> When a driver wants to add the GUID creation sysfs to an existing
> device it has
> probe'd to then it should call::
>
> - int mdev_register_device(struct device *dev,
> - struct mdev_driver *mdev_driver);
> + int mdev_register_parent(struct mdev_parent *parent, struct
> device *dev,
> + struct mdev_driver *mdev_driver);
>
> This will provide the 'mdev_supported_types/XX/create' files which
> can then be
> used to trigger the creation of a mdev_device. The created
> mdev_device will be
> @@ -136,7 +136,7 @@ attached to the specified driver.
>
> When the driver needs to remove itself it calls::
>
> - void mdev_unregister_device(struct device *dev);
> + void mdev_unregister_parent(struct mdev_parent *parent);
>
> Which will unbind and destroy all the created mdevs and remove the
> sysfs files.
>
> diff --git a/Documentation/s390/vfio-ap.rst
> b/Documentation/s390/vfio-ap.rst
> index f57ae621f33e8..37e16158c7fbf 100644
> --- a/Documentation/s390/vfio-ap.rst
> +++ b/Documentation/s390/vfio-ap.rst
> @@ -299,7 +299,7 @@ of the VFIO AP mediated matrix device driver::
> | MDEV CORE |
> | MODULE |
> | mdev.ko |
> - | +---------+ | mdev_register_device() +--------------+
> + | +---------+ | mdev_register_parent() +--------------+
> | |Physical | +<-----------------------+ |
> | | device | | | vfio_ap.ko |<-> matrix
> | |interface| +----------------------->+ | device
> diff --git a/Documentation/s390/vfio-ccw.rst
> b/Documentation/s390/vfio-ccw.rst
> index 8aad08a8b8a50..ea928a3806f43 100644
> --- a/Documentation/s390/vfio-ccw.rst
> +++ b/Documentation/s390/vfio-ccw.rst
> @@ -156,7 +156,7 @@ Below is a high Level block diagram::
> | MDEV CORE |
> | MODULE |
> | mdev.ko |
> - | +---------+ | mdev_register_device() +--------------+
> + | +---------+ | mdev_register_parent() +--------------+
> | |Physical | +<-----------------------+ |
> | | device | | | vfio_ccw.ko |<->
> subchannel
> | |interface| +----------------------->+ | device
> diff --git a/drivers/gpu/drm/i915/gvt/gvt.h
> b/drivers/gpu/drm/i915/gvt/gvt.h
> index 392c2ad49d376..bbf0116671ecb 100644
> --- a/drivers/gpu/drm/i915/gvt/gvt.h
> +++ b/drivers/gpu/drm/i915/gvt/gvt.h
> @@ -36,6 +36,7 @@
> #include <uapi/linux/pci_regs.h>
> #include <linux/kvm_host.h>
> #include <linux/vfio.h>
> +#include <linux/mdev.h>
>
> #include "i915_drv.h"
> #include "intel_gvt.h"
> @@ -338,6 +339,7 @@ struct intel_gvt {
> struct intel_gvt_workload_scheduler scheduler;
> struct notifier_block
> shadow_ctx_notifier_block[I915_NUM_ENGINES];
> DECLARE_HASHTABLE(cmd_table, GVT_CMD_HASH_BITS);
> + struct mdev_parent parent;
> struct intel_vgpu_type *types;
> unsigned int num_types;
> struct intel_vgpu *idle_vgpu;
> diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c
> b/drivers/gpu/drm/i915/gvt/kvmgt.c
> index 85e1393d8e55c..e9dba4c0fe6b5 100644
> --- a/drivers/gpu/drm/i915/gvt/kvmgt.c
> +++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
> @@ -1958,7 +1958,7 @@ static void intel_gvt_clean_device(struct
> drm_i915_private *i915)
> if (drm_WARN_ON(&i915->drm, !gvt))
> return;
>
> - mdev_unregister_device(i915->drm.dev);
> + mdev_unregister_parent(&gvt->parent);
> intel_gvt_cleanup_vgpu_type_groups(gvt);
> intel_gvt_destroy_idle_vgpu(gvt->idle_vgpu);
> intel_gvt_clean_vgpu_types(gvt);
> @@ -2063,7 +2063,8 @@ static int intel_gvt_init_device(struct
> drm_i915_private *i915)
> if (ret)
> goto out_destroy_idle_vgpu;
>
> - ret = mdev_register_device(i915->drm.dev,
> &intel_vgpu_mdev_driver);
> + ret = mdev_register_parent(&gvt->parent, i915->drm.dev,
> + &intel_vgpu_mdev_driver);
> if (ret)
> goto out_cleanup_vgpu_type_groups;
>
> diff --git a/drivers/s390/cio/cio.h b/drivers/s390/cio/cio.h
> index fa8df50bb49e3..22be5ac7d23c1 100644
> --- a/drivers/s390/cio/cio.h
> +++ b/drivers/s390/cio/cio.h
> @@ -5,6 +5,7 @@
> #include <linux/mutex.h>
> #include <linux/device.h>
> #include <linux/mod_devicetable.h>
> +#include <linux/mdev.h>
> #include <asm/chpid.h>
> #include <asm/cio.h>
> #include <asm/fcx.h>
> @@ -108,6 +109,7 @@ struct subchannel {
> * frees it. Use driver_set_override() to set or clear it.
> */
> const char *driver_override;
> + struct mdev_parent parent;
> } __attribute__ ((aligned(8)));
>
> DECLARE_PER_CPU_ALIGNED(struct irb, cio_irb);
> diff --git a/drivers/s390/cio/vfio_ccw_ops.c
> b/drivers/s390/cio/vfio_ccw_ops.c
> index b49e2e9db2dc6..9192a21085ce4 100644
> --- a/drivers/s390/cio/vfio_ccw_ops.c
> +++ b/drivers/s390/cio/vfio_ccw_ops.c
> @@ -11,7 +11,6 @@
> */
>
> #include <linux/vfio.h>
> -#include <linux/mdev.h>
> #include <linux/nospec.h>
> #include <linux/slab.h>
>
> @@ -660,10 +659,11 @@ struct mdev_driver vfio_ccw_mdev_driver = {
>
> int vfio_ccw_mdev_reg(struct subchannel *sch)
> {
> - return mdev_register_device(&sch->dev, &vfio_ccw_mdev_driver);
> + return mdev_register_parent(&sch->parent, &sch->dev,
> + &vfio_ccw_mdev_driver);
> }
>
> void vfio_ccw_mdev_unreg(struct subchannel *sch)
> {
> - mdev_unregister_device(&sch->dev);
> + mdev_unregister_parent(&sch->parent);
> }
> diff --git a/drivers/s390/crypto/vfio_ap_ops.c
> b/drivers/s390/crypto/vfio_ap_ops.c
> index a7d2a95796d36..834945150dc9f 100644
> --- a/drivers/s390/crypto/vfio_ap_ops.c
> +++ b/drivers/s390/crypto/vfio_ap_ops.c
> @@ -1485,7 +1485,8 @@ int vfio_ap_mdev_register(void)
> if (ret)
> return ret;
>
> - ret = mdev_register_device(&matrix_dev->device,
> &vfio_ap_matrix_driver);
> + ret = mdev_register_parent(&matrix_dev->parent, &matrix_dev-
> >device,
> + &vfio_ap_matrix_driver);
> if (ret)
> goto err_driver;
> return 0;
> @@ -1497,6 +1498,6 @@ int vfio_ap_mdev_register(void)
>
> void vfio_ap_mdev_unregister(void)
> {
> - mdev_unregister_device(&matrix_dev->device);
> + mdev_unregister_parent(&matrix_dev->parent);
> mdev_unregister_driver(&vfio_ap_matrix_driver);
> }
> diff --git a/drivers/s390/crypto/vfio_ap_private.h
> b/drivers/s390/crypto/vfio_ap_private.h
> index 6616aa83347ad..0191f6bc973a4 100644
> --- a/drivers/s390/crypto/vfio_ap_private.h
> +++ b/drivers/s390/crypto/vfio_ap_private.h
> @@ -45,6 +45,7 @@ struct ap_matrix_dev {
> struct list_head mdev_list;
> struct mutex lock;
> struct ap_driver *vfio_ap_drv;
> + struct mdev_parent parent;
> };
>
> extern struct ap_matrix_dev *matrix_dev;
> diff --git a/drivers/vfio/mdev/mdev_core.c
> b/drivers/vfio/mdev/mdev_core.c
> index 2c32923fbad27..fa05ac3396950 100644
> --- a/drivers/vfio/mdev/mdev_core.c
> +++ b/drivers/vfio/mdev/mdev_core.c
> @@ -18,8 +18,6 @@
> #define DRIVER_AUTHOR "NVIDIA Corporation"
> #define DRIVER_DESC "Mediated device Core Driver"
>
> -static LIST_HEAD(parent_list);
> -static DEFINE_MUTEX(parent_list_lock);
> static struct class_compat *mdev_bus_compat_class;
>
> static LIST_HEAD(mdev_list);
> @@ -61,28 +59,6 @@ struct device *mtype_get_parent_dev(struct
> mdev_type *mtype)
> }
> EXPORT_SYMBOL(mtype_get_parent_dev);
>
> -/* Should be called holding parent_list_lock */
> -static struct mdev_parent *__find_parent_device(struct device *dev)
> -{
> - struct mdev_parent *parent;
> -
> - list_for_each_entry(parent, &parent_list, next) {
> - if (parent->dev == dev)
> - return parent;
> - }
> - return NULL;
> -}
> -
> -void mdev_release_parent(struct kref *kref)
> -{
> - struct mdev_parent *parent = container_of(kref, struct
> mdev_parent,
> - ref);
> - struct device *dev = parent->dev;
> -
> - kfree(parent);
> - put_device(dev);
> -}
> -
> /* Caller must hold parent unreg_sem read or write lock */
> static void mdev_device_remove_common(struct mdev_device *mdev)
> {
> @@ -105,125 +81,73 @@ static int mdev_device_remove_cb(struct device
> *dev, void *data)
> }
>
> /*
> - * mdev_register_device : Register a device
> + * mdev_register_parent: Register a device as parent for mdevs
> + * @parent: parent structure registered
> * @dev: device structure representing parent device.
> * @mdev_driver: Device driver to bind to the newly created mdev
> *
> - * Add device to list of registered parent devices.
> + * Registers the @parent stucture as a parent for mdev types and
> thus mdev
> + * devices. The caller needs to hold a reference on @dev that must
> not be
> + * released until after the call to mdev_unregister_parent().
> + *
> * Returns a negative value on error, otherwise 0.
> */
> -int mdev_register_device(struct device *dev, struct mdev_driver
> *mdev_driver)
> +int mdev_register_parent(struct mdev_parent *parent, struct device
> *dev,
> + struct mdev_driver *mdev_driver)
> {
> - int ret;
> - struct mdev_parent *parent;
> char *env_string = "MDEV_STATE=registered";
> char *envp[] = { env_string, NULL };
> + int ret;
>
> /* check for mandatory ops */
> if (!mdev_driver->supported_type_groups)
> return -EINVAL;
>
> - dev = get_device(dev);
> - if (!dev)
> - return -EINVAL;
> -
> - mutex_lock(&parent_list_lock);
> -
> - /* Check for duplicate */
> - parent = __find_parent_device(dev);
> - if (parent) {
> - parent = NULL;
> - ret = -EEXIST;
> - goto add_dev_err;
> - }
> -
> - parent = kzalloc(sizeof(*parent), GFP_KERNEL);
> - if (!parent) {
> - ret = -ENOMEM;
> - goto add_dev_err;
> - }
> -
> - kref_init(&parent->ref);
> + memset(parent, 0, sizeof(*parent));
> init_rwsem(&parent->unreg_sem);
> -
> parent->dev = dev;
> parent->mdev_driver = mdev_driver;
>
> if (!mdev_bus_compat_class) {
> mdev_bus_compat_class =
> class_compat_register("mdev_bus");
> - if (!mdev_bus_compat_class) {
> - ret = -ENOMEM;
> - goto add_dev_err;
> - }
> + if (!mdev_bus_compat_class)
> + return -ENOMEM;
> }
>
> ret = parent_create_sysfs_files(parent);
> if (ret)
> - goto add_dev_err;
> + return ret;
>
> ret = class_compat_create_link(mdev_bus_compat_class, dev,
> NULL);
> if (ret)
> dev_warn(dev, "Failed to create compatibility class
> link\n");
>
> - list_add(&parent->next, &parent_list);
> - mutex_unlock(&parent_list_lock);
> -
> dev_info(dev, "MDEV: Registered\n");
> kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
> -
> return 0;
> -
> -add_dev_err:
> - mutex_unlock(&parent_list_lock);
> - if (parent)
> - mdev_put_parent(parent);
> - else
> - put_device(dev);
> - return ret;
> }
> -EXPORT_SYMBOL(mdev_register_device);
> +EXPORT_SYMBOL(mdev_register_parent);
>
> /*
> - * mdev_unregister_device : Unregister a parent device
> - * @dev: device structure representing parent device.
> - *
> - * Remove device from list of registered parent devices. Give a
> chance to free
> - * existing mediated devices for given device.
> + * mdev_unregister_parent : Unregister a parent device
> + * @parent: parent structure to unregister
> */
> -
> -void mdev_unregister_device(struct device *dev)
> +void mdev_unregister_parent(struct mdev_parent *parent)
> {
> - struct mdev_parent *parent;
> char *env_string = "MDEV_STATE=unregistered";
> char *envp[] = { env_string, NULL };
>
> - mutex_lock(&parent_list_lock);
> - parent = __find_parent_device(dev);
> -
> - if (!parent) {
> - mutex_unlock(&parent_list_lock);
> - return;
> - }
> - dev_info(dev, "MDEV: Unregistering\n");
> -
> - list_del(&parent->next);
> - mutex_unlock(&parent_list_lock);
> + dev_info(parent->dev, "MDEV: Unregistering\n");
>
> down_write(&parent->unreg_sem);
> -
> - class_compat_remove_link(mdev_bus_compat_class, dev, NULL);
> -
> - device_for_each_child(dev, NULL, mdev_device_remove_cb);
> -
> + class_compat_remove_link(mdev_bus_compat_class, parent->dev,
> NULL);
> + device_for_each_child(parent->dev, NULL,
> mdev_device_remove_cb);
> parent_remove_sysfs_files(parent);
> up_write(&parent->unreg_sem);
>
> - mdev_put_parent(parent);
> -
> - /* We still have the caller's reference to use for the uevent
> */
> - kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
> + kobject_uevent_env(&parent->dev->kobj, KOBJ_CHANGE, envp);
> }
> -EXPORT_SYMBOL(mdev_unregister_device);
> +EXPORT_SYMBOL(mdev_unregister_parent);
>
> static void mdev_device_release(struct device *dev)
> {
> diff --git a/drivers/vfio/mdev/mdev_private.h
> b/drivers/vfio/mdev/mdev_private.h
> index 7c9fc79f3d838..297f911fdc890 100644
> --- a/drivers/vfio/mdev/mdev_private.h
> +++ b/drivers/vfio/mdev/mdev_private.h
> @@ -13,17 +13,6 @@
> int mdev_bus_register(void);
> void mdev_bus_unregister(void);
>
> -struct mdev_parent {
> - struct device *dev;
> - struct mdev_driver *mdev_driver;
> - struct kref ref;
> - struct list_head next;
> - struct kset *mdev_types_kset;
> - struct list_head type_list;
> - /* Synchronize device creation/removal with parent
> unregistration */
> - struct rw_semaphore unreg_sem;
> -};
> -
> struct mdev_type {
> struct kobject kobj;
> struct kobject *devices_kobj;
> @@ -48,16 +37,4 @@ void mdev_remove_sysfs_files(struct mdev_device
> *mdev);
> int mdev_device_create(struct mdev_type *kobj, const guid_t *uuid);
> int mdev_device_remove(struct mdev_device *dev);
>
> -void mdev_release_parent(struct kref *kref);
> -
> -static inline void mdev_get_parent(struct mdev_parent *parent)
> -{
> - kref_get(&parent->ref);
> -}
> -
> -static inline void mdev_put_parent(struct mdev_parent *parent)
> -{
> - kref_put(&parent->ref, mdev_release_parent);
> -}
> -
> #endif /* MDEV_PRIVATE_H */
> diff --git a/drivers/vfio/mdev/mdev_sysfs.c
> b/drivers/vfio/mdev/mdev_sysfs.c
> index 4bfbf49aaa66a..b71ffc5594870 100644
> --- a/drivers/vfio/mdev/mdev_sysfs.c
> +++ b/drivers/vfio/mdev/mdev_sysfs.c
> @@ -81,7 +81,7 @@ static void mdev_type_release(struct kobject *kobj)
>
> pr_debug("Releasing group %s\n", kobj->name);
> /* Pairs with the get in add_mdev_supported_type() */
> - mdev_put_parent(type->parent);
> + put_device(type->parent->dev);
> kfree(type);
> }
>
> @@ -110,7 +110,7 @@ static struct mdev_type
> *add_mdev_supported_type(struct mdev_parent *parent,
> type->kobj.kset = parent->mdev_types_kset;
> type->parent = parent;
> /* Pairs with the put in mdev_type_release() */
> - mdev_get_parent(parent);
> + get_device(parent->dev);
> type->type_group_id = type_group_id;
>
> ret = kobject_init_and_add(&type->kobj, &mdev_type_ktype, NULL,
> diff --git a/include/linux/mdev.h b/include/linux/mdev.h
> index 555c1d015b5f0..327ce3e5c6b5f 100644
> --- a/include/linux/mdev.h
> +++ b/include/linux/mdev.h
> @@ -23,6 +23,16 @@ struct mdev_device {
> bool active;
> };
>
> +/* embedded into the struct device that the mdev devices hang off */
> +struct mdev_parent {
> + struct device *dev;
> + struct mdev_driver *mdev_driver;
> + struct kset *mdev_types_kset;
> + struct list_head type_list;
> + /* Synchronize device creation/removal with parent
> unregistration */
> + struct rw_semaphore unreg_sem;
> +};
> +
> static inline struct mdev_device *to_mdev_device(struct device *dev)
> {
> return container_of(dev, struct mdev_device, dev);
> @@ -75,8 +85,9 @@ static inline const guid_t *mdev_uuid(struct
> mdev_device *mdev)
>
> extern struct bus_type mdev_bus_type;
>
> -int mdev_register_device(struct device *dev, struct mdev_driver
> *mdev_driver);
> -void mdev_unregister_device(struct device *dev);
> +int mdev_register_parent(struct mdev_parent *parent, struct device
> *dev,
> + struct mdev_driver *mdev_driver);
> +void mdev_unregister_parent(struct mdev_parent *parent);
>
> int mdev_register_driver(struct mdev_driver *drv);
> void mdev_unregister_driver(struct mdev_driver *drv);
> diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c
> index d0d1bb7747240..30b3643b3b389 100644
> --- a/samples/vfio-mdev/mbochs.c
> +++ b/samples/vfio-mdev/mbochs.c
> @@ -128,6 +128,7 @@ static dev_t mbochs_devt;
> static struct class *mbochs_class;
> static struct cdev mbochs_cdev;
> static struct device mbochs_dev;
> +static struct mdev_parent mbochs_parent;
> static atomic_t mbochs_avail_mbytes;
> static const struct vfio_device_ops mbochs_dev_ops;
>
> @@ -1456,7 +1457,7 @@ static int __init mbochs_dev_init(void)
> if (ret)
> goto err_class;
>
> - ret = mdev_register_device(&mbochs_dev, &mbochs_driver);
> + ret = mdev_register_parent(&mbochs_parent, &mbochs_dev,
> &mbochs_driver);
> if (ret)
> goto err_device;
>
> @@ -1477,7 +1478,7 @@ static int __init mbochs_dev_init(void)
> static void __exit mbochs_dev_exit(void)
> {
> mbochs_dev.bus = NULL;
> - mdev_unregister_device(&mbochs_dev);
> + mdev_unregister_parent(&mbochs_parent);
>
> device_unregister(&mbochs_dev);
> mdev_unregister_driver(&mbochs_driver);
> diff --git a/samples/vfio-mdev/mdpy.c b/samples/vfio-mdev/mdpy.c
> index 0c4ca1f4be7ed..132bb055628a6 100644
> --- a/samples/vfio-mdev/mdpy.c
> +++ b/samples/vfio-mdev/mdpy.c
> @@ -83,6 +83,7 @@ static dev_t mdpy_devt;
> static struct class *mdpy_class;
> static struct cdev mdpy_cdev;
> static struct device mdpy_dev;
> +static struct mdev_parent mdpy_parent;
> static u32 mdpy_count;
> static const struct vfio_device_ops mdpy_dev_ops;
>
> @@ -765,7 +766,7 @@ static int __init mdpy_dev_init(void)
> if (ret)
> goto err_class;
>
> - ret = mdev_register_device(&mdpy_dev, &mdpy_driver);
> + ret = mdev_register_parent(&mdpy_parent, &mdpy_dev,
> &mdpy_driver);
> if (ret)
> goto err_device;
>
> @@ -786,7 +787,7 @@ static int __init mdpy_dev_init(void)
> static void __exit mdpy_dev_exit(void)
> {
> mdpy_dev.bus = NULL;
> - mdev_unregister_device(&mdpy_dev);
> + mdev_unregister_parent(&mdpy_parent);
>
> device_unregister(&mdpy_dev);
> mdev_unregister_driver(&mdpy_driver);
> diff --git a/samples/vfio-mdev/mtty.c b/samples/vfio-mdev/mtty.c
> index 4f5a6f2d3629d..8ba5f6084a093 100644
> --- a/samples/vfio-mdev/mtty.c
> +++ b/samples/vfio-mdev/mtty.c
> @@ -72,6 +72,7 @@ static struct mtty_dev {
> struct cdev vd_cdev;
> struct idr vd_idr;
> struct device dev;
> + struct mdev_parent parent;
> } mtty_dev;
>
> struct mdev_region_info {
> @@ -1350,7 +1351,8 @@ static int __init mtty_dev_init(void)
> if (ret)
> goto err_class;
>
> - ret = mdev_register_device(&mtty_dev.dev, &mtty_driver);
> + ret = mdev_register_parent(&mtty_dev.parent, &mtty_dev.dev,
> + &mtty_driver);
> if (ret)
> goto err_device;
> return 0;
> @@ -1370,7 +1372,7 @@ static int __init mtty_dev_init(void)
> static void __exit mtty_dev_exit(void)
> {
> mtty_dev.dev.bus = NULL;
> - mdev_unregister_device(&mtty_dev.dev);
> + mdev_unregister_parent(&mtty_dev.parent);
>
> device_unregister(&mtty_dev.dev);
> idr_destroy(&mtty_dev.vd_idr);
^ permalink raw reply [flat|nested] 31+ messages in thread
* Re: [PATCH 14/15] vfio/mdev: add mdev available instance checking to the core
2022-07-06 7:42 ` [PATCH 14/15] vfio/mdev: add mdev available instance checking to the core Christoph Hellwig
2022-07-06 13:37 ` Kirti Wankhede
@ 2022-07-07 3:08 ` Eric Farman
2022-07-08 5:48 ` Christoph Hellwig
1 sibling, 1 reply; 31+ messages in thread
From: Eric Farman @ 2022-07-07 3:08 UTC (permalink / raw)
To: Christoph Hellwig, Kirti Wankhede, Tony Krowiak, Halil Pasic,
Jason Herne, Matthew Rosato, Zhenyu Wang, Zhi Wang,
Alex Williamson
Cc: Jason Gunthorpe, kvm, linux-s390, intel-gvt-dev, Kevin Tian
On Wed, 2022-07-06 at 09:42 +0200, Christoph Hellwig wrote:
> Many of the mdev drivers use a simple counter for keeping track of
> the
> available instances. Move this code to the core code and store the
> counter
> in the mdev_parent. Implement it using correct locking, fixing mdpy.
>
> Drivers just provide the value in the mdev_driver at registration
> time
> and the core code takes care of maintaining it and exposing the value
> in
> sysfs.
If I read this right, .get_available and .max_instances are mutually
exclusive. Which means that available_instances_show() from patch 12
would need to emit parent->available_instances if .get_available is
NULL.
Eric
>
> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
> [count instances per-parent instead of per-type]
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> Reviewed-by: Kevin Tian <kevin.tian@intel.com>
> ---
> drivers/s390/cio/vfio_ccw_drv.c | 1 -
> drivers/s390/cio/vfio_ccw_ops.c | 14 +-------------
> drivers/s390/cio/vfio_ccw_private.h | 2 --
> drivers/s390/crypto/vfio_ap_ops.c | 21 +++------------------
> drivers/s390/crypto/vfio_ap_private.h | 2 --
> drivers/vfio/mdev/mdev_core.c | 18 +++++++++++++++---
> include/linux/mdev.h | 3 +++
> samples/vfio-mdev/mdpy.c | 23 ++++-------------------
> 8 files changed, 26 insertions(+), 58 deletions(-)
>
> diff --git a/drivers/s390/cio/vfio_ccw_drv.c
> b/drivers/s390/cio/vfio_ccw_drv.c
> index 750d0315f1f5b..449c76b29a3b5 100644
> --- a/drivers/s390/cio/vfio_ccw_drv.c
> +++ b/drivers/s390/cio/vfio_ccw_drv.c
> @@ -149,7 +149,6 @@ static struct vfio_ccw_private
> *vfio_ccw_alloc_private(struct subchannel *sch)
> INIT_LIST_HEAD(&private->crw);
> INIT_WORK(&private->io_work, vfio_ccw_sch_io_todo);
> INIT_WORK(&private->crw_work, vfio_ccw_crw_todo);
> - atomic_set(&private->avail, 1);
>
> private->cp.guest_cp = kcalloc(CCWCHAIN_LEN_MAX, sizeof(struct
> ccw1),
> GFP_KERNEL);
> diff --git a/drivers/s390/cio/vfio_ccw_ops.c
> b/drivers/s390/cio/vfio_ccw_ops.c
> index 6f6a0f2695059..c05d80add7be2 100644
> --- a/drivers/s390/cio/vfio_ccw_ops.c
> +++ b/drivers/s390/cio/vfio_ccw_ops.c
> @@ -70,13 +70,6 @@ static int vfio_ccw_mdev_notifier(struct
> notifier_block *nb,
> return NOTIFY_DONE;
> }
>
> -static unsigned int vfio_ccw_get_available(struct mdev_type *mtype)
> -{
> - struct vfio_ccw_private *private = dev_get_drvdata(mtype-
> >parent->dev);
> -
> - return atomic_read(&private->avail);
> -}
> -
> static int vfio_ccw_mdev_probe(struct mdev_device *mdev)
> {
> struct vfio_ccw_private *private = dev_get_drvdata(mdev-
> >dev.parent);
> @@ -85,9 +78,6 @@ static int vfio_ccw_mdev_probe(struct mdev_device
> *mdev)
> if (private->state == VFIO_CCW_STATE_NOT_OPER)
> return -ENODEV;
>
> - if (atomic_dec_if_positive(&private->avail) < 0)
> - return -EPERM;
> -
> memset(&private->vdev, 0, sizeof(private->vdev));
> vfio_init_group_dev(&private->vdev, &mdev->dev,
> &vfio_ccw_dev_ops);
> @@ -108,7 +98,6 @@ static int vfio_ccw_mdev_probe(struct mdev_device
> *mdev)
>
> err_atomic:
> vfio_uninit_group_dev(&private->vdev);
> - atomic_inc(&private->avail);
> private->mdev = NULL;
> private->state = VFIO_CCW_STATE_IDLE;
> return ret;
> @@ -135,7 +124,6 @@ static void vfio_ccw_mdev_remove(struct
> mdev_device *mdev)
> vfio_uninit_group_dev(&private->vdev);
> cp_free(&private->cp);
> private->mdev = NULL;
> - atomic_inc(&private->avail);
> }
>
> static int vfio_ccw_mdev_open_device(struct vfio_device *vdev)
> @@ -613,6 +601,7 @@ static const struct vfio_device_ops
> vfio_ccw_dev_ops = {
>
> struct mdev_driver vfio_ccw_mdev_driver = {
> .device_api = VFIO_DEVICE_API_CCW_STRING,
> + .max_instances = 1,
> .driver = {
> .name = "vfio_ccw_mdev",
> .owner = THIS_MODULE,
> @@ -620,7 +609,6 @@ struct mdev_driver vfio_ccw_mdev_driver = {
> },
> .probe = vfio_ccw_mdev_probe,
> .remove = vfio_ccw_mdev_remove,
> - .get_available = vfio_ccw_get_available,
> };
>
> int vfio_ccw_mdev_reg(struct subchannel *sch)
> diff --git a/drivers/s390/cio/vfio_ccw_private.h
> b/drivers/s390/cio/vfio_ccw_private.h
> index b7163bac8cc75..9be5baed0cb7f 100644
> --- a/drivers/s390/cio/vfio_ccw_private.h
> +++ b/drivers/s390/cio/vfio_ccw_private.h
> @@ -72,7 +72,6 @@ struct vfio_ccw_crw {
> * @sch: pointer to the subchannel
> * @state: internal state of the device
> * @completion: synchronization helper of the I/O completion
> - * @avail: available for creating a mediated device
> * @mdev: pointer to the mediated device
> * @nb: notifier for vfio events
> * @io_region: MMIO region to input/output I/O arguments/results
> @@ -96,7 +95,6 @@ struct vfio_ccw_private {
> struct subchannel *sch;
> int state;
> struct completion *completion;
> - atomic_t avail;
> struct mdev_device *mdev;
> struct notifier_block nb;
> struct ccw_io_region *io_region;
> diff --git a/drivers/s390/crypto/vfio_ap_ops.c
> b/drivers/s390/crypto/vfio_ap_ops.c
> index edeec11c56560..69ed88fdaf383 100644
> --- a/drivers/s390/crypto/vfio_ap_ops.c
> +++ b/drivers/s390/crypto/vfio_ap_ops.c
> @@ -461,14 +461,9 @@ static int vfio_ap_mdev_probe(struct mdev_device
> *mdev)
> struct ap_matrix_mdev *matrix_mdev;
> int ret;
>
> - if ((atomic_dec_if_positive(&matrix_dev->available_instances) <
> 0))
> - return -EPERM;
> -
> matrix_mdev = kzalloc(sizeof(*matrix_mdev), GFP_KERNEL);
> - if (!matrix_mdev) {
> - ret = -ENOMEM;
> - goto err_dec_available;
> - }
> + if (!matrix_mdev)
> + return -ENOMEM;
> vfio_init_group_dev(&matrix_mdev->vdev, &mdev->dev,
> &vfio_ap_matrix_dev_ops);
>
> @@ -491,8 +486,6 @@ static int vfio_ap_mdev_probe(struct mdev_device
> *mdev)
> mutex_unlock(&matrix_dev->lock);
> vfio_uninit_group_dev(&matrix_mdev->vdev);
> kfree(matrix_mdev);
> -err_dec_available:
> - atomic_inc(&matrix_dev->available_instances);
> return ret;
> }
>
> @@ -508,12 +501,6 @@ static void vfio_ap_mdev_remove(struct
> mdev_device *mdev)
> mutex_unlock(&matrix_dev->lock);
> vfio_uninit_group_dev(&matrix_mdev->vdev);
> kfree(matrix_mdev);
> - atomic_inc(&matrix_dev->available_instances);
> -}
> -
> -static unsigned int vfio_ap_mdev_get_available(struct mdev_type
> *mtype)
> -{
> - return atomic_read(&matrix_dev->available_instances);
> }
>
> struct vfio_ap_queue_reserved {
> @@ -1427,6 +1414,7 @@ static const struct vfio_device_ops
> vfio_ap_matrix_dev_ops = {
>
> static struct mdev_driver vfio_ap_matrix_driver = {
> .device_api = VFIO_DEVICE_API_AP_STRING,
> + .max_instances = MAX_ZDEV_ENTRIES_EXT,
> .driver = {
> .name = "vfio_ap_mdev",
> .owner = THIS_MODULE,
> @@ -1435,15 +1423,12 @@ static struct mdev_driver
> vfio_ap_matrix_driver = {
> },
> .probe = vfio_ap_mdev_probe,
> .remove = vfio_ap_mdev_remove,
> - .get_available = vfio_ap_mdev_get_available,
> };
>
> int vfio_ap_mdev_register(void)
> {
> int ret;
>
> - atomic_set(&matrix_dev->available_instances,
> MAX_ZDEV_ENTRIES_EXT);
> -
> ret = mdev_register_driver(&vfio_ap_matrix_driver);
> if (ret)
> return ret;
> diff --git a/drivers/s390/crypto/vfio_ap_private.h
> b/drivers/s390/crypto/vfio_ap_private.h
> index 5dc5050d03791..b808b343b771f 100644
> --- a/drivers/s390/crypto/vfio_ap_private.h
> +++ b/drivers/s390/crypto/vfio_ap_private.h
> @@ -28,7 +28,6 @@
> * struct ap_matrix_dev - Contains the data for the matrix device.
> *
> * @device: generic device structure associated with the AP matrix
> device
> - * @available_instances: number of mediated matrix devices that can
> be created
> * @info: the struct containing the output from the PQAP(QCI)
> instruction
> * @mdev_list: the list of mediated matrix devices created
> * @lock: mutex for locking the AP matrix device. This lock will
> be
> @@ -40,7 +39,6 @@
> */
> struct ap_matrix_dev {
> struct device device;
> - atomic_t available_instances;
> struct ap_config_info info;
> struct list_head mdev_list;
> struct mutex lock;
> diff --git a/drivers/vfio/mdev/mdev_core.c
> b/drivers/vfio/mdev/mdev_core.c
> index 93f8caf2e5f77..9bc897235c492 100644
> --- a/drivers/vfio/mdev/mdev_core.c
> +++ b/drivers/vfio/mdev/mdev_core.c
> @@ -70,6 +70,7 @@ int mdev_register_parent(struct mdev_parent
> *parent, struct device *dev,
> parent->mdev_driver = mdev_driver;
> parent->types = types;
> parent->nr_types = nr_types;
> + parent->available_instances = mdev_driver->max_instances;
>
> if (!mdev_bus_compat_class) {
> mdev_bus_compat_class =
> class_compat_register("mdev_bus");
> @@ -115,14 +116,17 @@ EXPORT_SYMBOL(mdev_unregister_parent);
> static void mdev_device_release(struct device *dev)
> {
> struct mdev_device *mdev = to_mdev_device(dev);
> -
> - /* Pairs with the get in mdev_device_create() */
> - kobject_put(&mdev->type->kobj);
> + struct mdev_parent *parent = mdev->type->parent;
>
> mutex_lock(&mdev_list_lock);
> list_del(&mdev->next);
> + if (!parent->mdev_driver->get_available)
> + parent->available_instances++;
> mutex_unlock(&mdev_list_lock);
>
> + /* Pairs with the get in mdev_device_create() */
> + kobject_put(&mdev->type->kobj);
> +
> dev_dbg(&mdev->dev, "MDEV: destroying\n");
> kfree(mdev);
> }
> @@ -144,6 +148,14 @@ int mdev_device_create(struct mdev_type *type,
> const guid_t *uuid)
> }
> }
>
> + if (!drv->get_available) {
> + if (!parent->available_instances) {
> + mutex_unlock(&mdev_list_lock);
> + return -EUSERS;
> + }
> + parent->available_instances--;
> + }
> +
> mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
> if (!mdev) {
> mutex_unlock(&mdev_list_lock);
> diff --git a/include/linux/mdev.h b/include/linux/mdev.h
> index dc38ad2b07883..641ed18a61247 100644
> --- a/include/linux/mdev.h
> +++ b/include/linux/mdev.h
> @@ -45,6 +45,7 @@ struct mdev_parent {
> struct rw_semaphore unreg_sem;
> struct mdev_type **types;
> unsigned int nr_types;
> + unsigned int available_instances;
> };
>
> static inline struct mdev_device *to_mdev_device(struct device *dev)
> @@ -55,6 +56,7 @@ static inline struct mdev_device
> *to_mdev_device(struct device *dev)
> /**
> * struct mdev_driver - Mediated device driver
> * @device_api: string to return for the device_api sysfs
> + * @max_instances: maximum number of instances supported (optional)
> * @probe: called when new device created
> * @remove: called when device removed
> * @get_available: Return the max number of instances that can be
> created
> @@ -63,6 +65,7 @@ static inline struct mdev_device
> *to_mdev_device(struct device *dev)
> **/
> struct mdev_driver {
> const char *device_api;
> + unsigned int max_instances;
> int (*probe)(struct mdev_device *dev);
> void (*remove)(struct mdev_device *dev);
> unsigned int (*get_available)(struct mdev_type *mtype);
> diff --git a/samples/vfio-mdev/mdpy.c b/samples/vfio-mdev/mdpy.c
> index 250b7ea2df2e4..7f7ac5491407e 100644
> --- a/samples/vfio-mdev/mdpy.c
> +++ b/samples/vfio-mdev/mdpy.c
> @@ -42,11 +42,6 @@
>
> MODULE_LICENSE("GPL v2");
>
> -static int max_devices = 4;
> -module_param_named(count, max_devices, int, 0444);
> -MODULE_PARM_DESC(count, "number of " MDPY_NAME " devices");
> -
> -
> #define MDPY_TYPE_1 "vga"
> #define MDPY_TYPE_2 "xga"
> #define MDPY_TYPE_3 "hd"
> @@ -93,7 +88,6 @@ static struct class *mdpy_class;
> static struct cdev mdpy_cdev;
> static struct device mdpy_dev;
> static struct mdev_parent mdpy_parent;
> -static u32 mdpy_count;
> static const struct vfio_device_ops mdpy_dev_ops;
>
> /* State of each mdev device */
> @@ -234,9 +228,6 @@ static int mdpy_probe(struct mdev_device *mdev)
> u32 fbsize;
> int ret;
>
> - if (mdpy_count >= max_devices)
> - return -ENOMEM;
> -
> mdev_state = kzalloc(sizeof(struct mdev_state), GFP_KERNEL);
> if (mdev_state == NULL)
> return -ENOMEM;
> @@ -265,8 +256,6 @@ static int mdpy_probe(struct mdev_device *mdev)
> mdpy_create_config_space(mdev_state);
> mdpy_reset(mdev_state);
>
> - mdpy_count++;
> -
> ret = vfio_register_emulated_iommu_dev(&mdev_state->vdev);
> if (ret)
> goto err_mem;
> @@ -293,8 +282,6 @@ static void mdpy_remove(struct mdev_device *mdev)
> kfree(mdev_state->vconfig);
> vfio_uninit_group_dev(&mdev_state->vdev);
> kfree(mdev_state);
> -
> - mdpy_count--;
> }
>
> static ssize_t mdpy_read(struct vfio_device *vdev, char __user *buf,
> @@ -658,11 +645,6 @@ static ssize_t mdpy_show_description(struct
> mdev_type *mtype, char *buf)
> type->width, type->height);
> }
>
> -static unsigned int mdpy_get_available(struct mdev_type *mtype)
> -{
> - return max_devices - mdpy_count;
> -}
> -
> static const struct vfio_device_ops mdpy_dev_ops = {
> .read = mdpy_read,
> .write = mdpy_write,
> @@ -672,6 +654,7 @@ static const struct vfio_device_ops mdpy_dev_ops
> = {
>
> static struct mdev_driver mdpy_driver = {
> .device_api = VFIO_DEVICE_API_PCI_STRING,
> + .max_instances = 4,
> .driver = {
> .name = "mdpy",
> .owner = THIS_MODULE,
> @@ -680,7 +663,6 @@ static struct mdev_driver mdpy_driver = {
> },
> .probe = mdpy_probe,
> .remove = mdpy_remove,
> - .get_available = mdpy_get_available,
> .show_description = mdpy_show_description,
> };
>
> @@ -757,5 +739,8 @@ static void __exit mdpy_dev_exit(void)
> mdpy_class = NULL;
> }
>
> +module_param_named(count, mdpy_driver.max_instances, int, 0444);
> +MODULE_PARM_DESC(count, "number of " MDPY_NAME " devices");
> +
> module_init(mdpy_dev_init)
> module_exit(mdpy_dev_exit)
^ permalink raw reply [flat|nested] 31+ messages in thread
* Re: [PATCH 04/15] vfio/mdev: embedd struct mdev_parent in the parent data structure
2022-07-07 3:08 ` Eric Farman
@ 2022-07-07 7:22 ` Vineeth Vijayan
2022-07-07 13:40 ` Christoph Hellwig
0 siblings, 1 reply; 31+ messages in thread
From: Vineeth Vijayan @ 2022-07-07 7:22 UTC (permalink / raw)
To: Eric Farman
Cc: Christoph Hellwig, Kirti Wankhede, Tony Krowiak, Halil Pasic,
Jason Herne, Matthew Rosato, Zhenyu Wang, Zhi Wang,
Alex Williamson, Peter Oberparleiter, Jason Gunthorpe, kvm,
linux-s390, intel-gvt-dev, Kevin Tian
On Wed, Jul 06, 2022 at 11:08:28PM -0400, Eric Farman wrote:
> On Wed, 2022-07-06 at 09:42 +0200, Christoph Hellwig wrote:
> > Simplify mdev_{un}register_device by requiring the caller to pass in
> > a structure allocate as part of the parent device structure. This
> > removes the need for a list of parents and the separate mdev_parent
> > refcount as we can simplify rely on the reference to the parent
> > device.
> >
> > Signed-off-by: Christoph Hellwig <hch@lst.de>
> > Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
> > Reviewed-by: Kevin Tian <kevin.tian@intel.com>
> > ---
> > .../driver-api/vfio-mediated-device.rst | 12 +-
> > Documentation/s390/vfio-ap.rst | 2 +-
> > Documentation/s390/vfio-ccw.rst | 2 +-
> > drivers/gpu/drm/i915/gvt/gvt.h | 2 +
> > drivers/gpu/drm/i915/gvt/kvmgt.c | 5 +-
> > drivers/s390/cio/cio.h | 2 +
> > drivers/s390/cio/vfio_ccw_ops.c | 6 +-
>
> (@Vineeth, @Peter FYI regarding struct subchannel)
>
> I haven't had a chance to look at this series with enough focus, but
> the change to cio.h (here, and patch 5) caught my eye. I would've
> expected the "parent" to be struct vfio_ccw_private, instead of the
> subchannel.
>
> Eric
Thank you Eric for pointing it out. You are right. I think the struct
subchannel is obviously the wrong place.
Also, in this case, the mdev_parent should be in one of the vfio-ccw
io-subchannel structure, which as you mentioned should be in vfio-ccw*.
@Halil, Could you please have a look. I am not very familier with the
vfio yet.
>
> > drivers/s390/crypto/vfio_ap_ops.c | 5 +-
> > drivers/s390/crypto/vfio_ap_private.h | 1 +
> > drivers/vfio/mdev/mdev_core.c | 120 ++++----------
> > ----
> > drivers/vfio/mdev/mdev_private.h | 23 ----
> > drivers/vfio/mdev/mdev_sysfs.c | 4 +-
> > include/linux/mdev.h | 15 ++-
> > samples/vfio-mdev/mbochs.c | 5 +-
> > samples/vfio-mdev/mdpy.c | 5 +-
> > samples/vfio-mdev/mtty.c | 6 +-
> > 16 files changed, 69 insertions(+), 146 deletions(-)
> >
> > diff --git a/Documentation/driver-api/vfio-mediated-device.rst
> > b/Documentation/driver-api/vfio-mediated-device.rst
> > index 1c57815619fdf..62a82afce161b 100644
> > --- a/Documentation/driver-api/vfio-mediated-device.rst
> > +++ b/Documentation/driver-api/vfio-mediated-device.rst
> > @@ -60,19 +60,19 @@ devices as examples, as these devices are the
> > first devices to use this module::
> > | MDEV CORE |
> > | MODULE |
> > | mdev.ko |
> > - | +-----------+ | mdev_register_device() +--------------+
> > + | +-----------+ | mdev_register_parent() +--------------+
> > | | | +<------------------------+ |
> > | | | | | nvidia.ko |<->
> > physical
> > | | | +----------------------
> > -->+ | device
> > | | | | callbacks +--------------+
> > | | Physical | |
> > - | | device | | mdev_register_device() +--------------+
> > + | | device | | mdev_register_parent() +--------------+
> > | | interface | |<------------------------+ |
> > | | | | | i915.ko |<->
> > physical
> > | | | +----------------------
> > -->+ | device
> > | | | | callbacks +--------------+
> > | | | |
> > - | | | | mdev_register_device() +--------------+
> > + | | | | mdev_register_parent() +--------------+
> > | | | +<------------------------+ |
> > | | | | | ccw_device.ko|<->
> > physical
> > | | | +----------------------
> > -->+ | device
> > @@ -127,8 +127,8 @@ vfio_device_ops.
> > When a driver wants to add the GUID creation sysfs to an existing
> > device it has
> > probe'd to then it should call::
> >
> > - int mdev_register_device(struct device *dev,
> > - struct mdev_driver *mdev_driver);
> > + int mdev_register_parent(struct mdev_parent *parent, struct
> > device *dev,
> > + struct mdev_driver *mdev_driver);
> >
> > This will provide the 'mdev_supported_types/XX/create' files which
> > can then be
> > used to trigger the creation of a mdev_device. The created
> > mdev_device will be
> > @@ -136,7 +136,7 @@ attached to the specified driver.
> >
> > When the driver needs to remove itself it calls::
> >
> > - void mdev_unregister_device(struct device *dev);
> > + void mdev_unregister_parent(struct mdev_parent *parent);
> >
> > Which will unbind and destroy all the created mdevs and remove the
> > sysfs files.
> >
> > diff --git a/Documentation/s390/vfio-ap.rst
> > b/Documentation/s390/vfio-ap.rst
> > index f57ae621f33e8..37e16158c7fbf 100644
> > --- a/Documentation/s390/vfio-ap.rst
> > +++ b/Documentation/s390/vfio-ap.rst
> > @@ -299,7 +299,7 @@ of the VFIO AP mediated matrix device driver::
> > | MDEV CORE |
> > | MODULE |
> > | mdev.ko |
> > - | +---------+ | mdev_register_device() +--------------+
> > + | +---------+ | mdev_register_parent() +--------------+
> > | |Physical | +<-----------------------+ |
> > | | device | | | vfio_ap.ko |<-> matrix
> > | |interface| +----------------------->+ | device
> > diff --git a/Documentation/s390/vfio-ccw.rst
> > b/Documentation/s390/vfio-ccw.rst
> > index 8aad08a8b8a50..ea928a3806f43 100644
> > --- a/Documentation/s390/vfio-ccw.rst
> > +++ b/Documentation/s390/vfio-ccw.rst
> > @@ -156,7 +156,7 @@ Below is a high Level block diagram::
> > | MDEV CORE |
> > | MODULE |
> > | mdev.ko |
> > - | +---------+ | mdev_register_device() +--------------+
> > + | +---------+ | mdev_register_parent() +--------------+
> > | |Physical | +<-----------------------+ |
> > | | device | | | vfio_ccw.ko |<->
> > subchannel
> > | |interface| +----------------------->+ | device
> > diff --git a/drivers/gpu/drm/i915/gvt/gvt.h
> > b/drivers/gpu/drm/i915/gvt/gvt.h
> > index 392c2ad49d376..bbf0116671ecb 100644
> > --- a/drivers/gpu/drm/i915/gvt/gvt.h
> > +++ b/drivers/gpu/drm/i915/gvt/gvt.h
> > @@ -36,6 +36,7 @@
> > #include <uapi/linux/pci_regs.h>
> > #include <linux/kvm_host.h>
> > #include <linux/vfio.h>
> > +#include <linux/mdev.h>
> >
> > #include "i915_drv.h"
> > #include "intel_gvt.h"
> > @@ -338,6 +339,7 @@ struct intel_gvt {
> > struct intel_gvt_workload_scheduler scheduler;
> > struct notifier_block
> > shadow_ctx_notifier_block[I915_NUM_ENGINES];
> > DECLARE_HASHTABLE(cmd_table, GVT_CMD_HASH_BITS);
> > + struct mdev_parent parent;
> > struct intel_vgpu_type *types;
> > unsigned int num_types;
> > struct intel_vgpu *idle_vgpu;
> > diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c
> > b/drivers/gpu/drm/i915/gvt/kvmgt.c
> > index 85e1393d8e55c..e9dba4c0fe6b5 100644
> > --- a/drivers/gpu/drm/i915/gvt/kvmgt.c
> > +++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
> > @@ -1958,7 +1958,7 @@ static void intel_gvt_clean_device(struct
> > drm_i915_private *i915)
> > if (drm_WARN_ON(&i915->drm, !gvt))
> > return;
> >
> > - mdev_unregister_device(i915->drm.dev);
> > + mdev_unregister_parent(&gvt->parent);
> > intel_gvt_cleanup_vgpu_type_groups(gvt);
> > intel_gvt_destroy_idle_vgpu(gvt->idle_vgpu);
> > intel_gvt_clean_vgpu_types(gvt);
> > @@ -2063,7 +2063,8 @@ static int intel_gvt_init_device(struct
> > drm_i915_private *i915)
> > if (ret)
> > goto out_destroy_idle_vgpu;
> >
> > - ret = mdev_register_device(i915->drm.dev,
> > &intel_vgpu_mdev_driver);
> > + ret = mdev_register_parent(&gvt->parent, i915->drm.dev,
> > + &intel_vgpu_mdev_driver);
> > if (ret)
> > goto out_cleanup_vgpu_type_groups;
> >
> > diff --git a/drivers/s390/cio/cio.h b/drivers/s390/cio/cio.h
> > index fa8df50bb49e3..22be5ac7d23c1 100644
> > --- a/drivers/s390/cio/cio.h
> > +++ b/drivers/s390/cio/cio.h
> > @@ -5,6 +5,7 @@
> > #include <linux/mutex.h>
> > #include <linux/device.h>
> > #include <linux/mod_devicetable.h>
> > +#include <linux/mdev.h>
> > #include <asm/chpid.h>
> > #include <asm/cio.h>
> > #include <asm/fcx.h>
> > @@ -108,6 +109,7 @@ struct subchannel {
> > * frees it. Use driver_set_override() to set or clear it.
> > */
> > const char *driver_override;
> > + struct mdev_parent parent;
> > } __attribute__ ((aligned(8)));
> >
> > DECLARE_PER_CPU_ALIGNED(struct irb, cio_irb);
> > diff --git a/drivers/s390/cio/vfio_ccw_ops.c
> > b/drivers/s390/cio/vfio_ccw_ops.c
> > index b49e2e9db2dc6..9192a21085ce4 100644
> > --- a/drivers/s390/cio/vfio_ccw_ops.c
> > +++ b/drivers/s390/cio/vfio_ccw_ops.c
> > @@ -11,7 +11,6 @@
> > */
> >
> > #include <linux/vfio.h>
> > -#include <linux/mdev.h>
> > #include <linux/nospec.h>
> > #include <linux/slab.h>
> >
> > @@ -660,10 +659,11 @@ struct mdev_driver vfio_ccw_mdev_driver = {
> >
> > int vfio_ccw_mdev_reg(struct subchannel *sch)
> > {
> > - return mdev_register_device(&sch->dev, &vfio_ccw_mdev_driver);
> > + return mdev_register_parent(&sch->parent, &sch->dev,
> > + &vfio_ccw_mdev_driver);
> > }
> >
> > void vfio_ccw_mdev_unreg(struct subchannel *sch)
> > {
> > - mdev_unregister_device(&sch->dev);
> > + mdev_unregister_parent(&sch->parent);
> > }
> > diff --git a/drivers/s390/crypto/vfio_ap_ops.c
> > b/drivers/s390/crypto/vfio_ap_ops.c
> > index a7d2a95796d36..834945150dc9f 100644
> > --- a/drivers/s390/crypto/vfio_ap_ops.c
> > +++ b/drivers/s390/crypto/vfio_ap_ops.c
> > @@ -1485,7 +1485,8 @@ int vfio_ap_mdev_register(void)
> > if (ret)
> > return ret;
> >
> > - ret = mdev_register_device(&matrix_dev->device,
> > &vfio_ap_matrix_driver);
> > + ret = mdev_register_parent(&matrix_dev->parent, &matrix_dev-
> > >device,
> > + &vfio_ap_matrix_driver);
> > if (ret)
> > goto err_driver;
> > return 0;
> > @@ -1497,6 +1498,6 @@ int vfio_ap_mdev_register(void)
> >
> > void vfio_ap_mdev_unregister(void)
> > {
> > - mdev_unregister_device(&matrix_dev->device);
> > + mdev_unregister_parent(&matrix_dev->parent);
> > mdev_unregister_driver(&vfio_ap_matrix_driver);
> > }
> > diff --git a/drivers/s390/crypto/vfio_ap_private.h
> > b/drivers/s390/crypto/vfio_ap_private.h
> > index 6616aa83347ad..0191f6bc973a4 100644
> > --- a/drivers/s390/crypto/vfio_ap_private.h
> > +++ b/drivers/s390/crypto/vfio_ap_private.h
> > @@ -45,6 +45,7 @@ struct ap_matrix_dev {
> > struct list_head mdev_list;
> > struct mutex lock;
> > struct ap_driver *vfio_ap_drv;
> > + struct mdev_parent parent;
> > };
> >
> > extern struct ap_matrix_dev *matrix_dev;
> > diff --git a/drivers/vfio/mdev/mdev_core.c
> > b/drivers/vfio/mdev/mdev_core.c
> > index 2c32923fbad27..fa05ac3396950 100644
> > --- a/drivers/vfio/mdev/mdev_core.c
> > +++ b/drivers/vfio/mdev/mdev_core.c
> > @@ -18,8 +18,6 @@
> > #define DRIVER_AUTHOR "NVIDIA Corporation"
> > #define DRIVER_DESC "Mediated device Core Driver"
> >
> > -static LIST_HEAD(parent_list);
> > -static DEFINE_MUTEX(parent_list_lock);
> > static struct class_compat *mdev_bus_compat_class;
> >
> > static LIST_HEAD(mdev_list);
> > @@ -61,28 +59,6 @@ struct device *mtype_get_parent_dev(struct
> > mdev_type *mtype)
> > }
> > EXPORT_SYMBOL(mtype_get_parent_dev);
> >
> > -/* Should be called holding parent_list_lock */
> > -static struct mdev_parent *__find_parent_device(struct device *dev)
> > -{
> > - struct mdev_parent *parent;
> > -
> > - list_for_each_entry(parent, &parent_list, next) {
> > - if (parent->dev == dev)
> > - return parent;
> > - }
> > - return NULL;
> > -}
> > -
> > -void mdev_release_parent(struct kref *kref)
> > -{
> > - struct mdev_parent *parent = container_of(kref, struct
> > mdev_parent,
> > - ref);
> > - struct device *dev = parent->dev;
> > -
> > - kfree(parent);
> > - put_device(dev);
> > -}
> > -
> > /* Caller must hold parent unreg_sem read or write lock */
> > static void mdev_device_remove_common(struct mdev_device *mdev)
> > {
> > @@ -105,125 +81,73 @@ static int mdev_device_remove_cb(struct device
> > *dev, void *data)
> > }
> >
> > /*
> > - * mdev_register_device : Register a device
> > + * mdev_register_parent: Register a device as parent for mdevs
> > + * @parent: parent structure registered
> > * @dev: device structure representing parent device.
> > * @mdev_driver: Device driver to bind to the newly created mdev
> > *
> > - * Add device to list of registered parent devices.
> > + * Registers the @parent stucture as a parent for mdev types and
> > thus mdev
> > + * devices. The caller needs to hold a reference on @dev that must
> > not be
> > + * released until after the call to mdev_unregister_parent().
> > + *
> > * Returns a negative value on error, otherwise 0.
> > */
> > -int mdev_register_device(struct device *dev, struct mdev_driver
> > *mdev_driver)
> > +int mdev_register_parent(struct mdev_parent *parent, struct device
> > *dev,
> > + struct mdev_driver *mdev_driver)
> > {
> > - int ret;
> > - struct mdev_parent *parent;
> > char *env_string = "MDEV_STATE=registered";
> > char *envp[] = { env_string, NULL };
> > + int ret;
> >
> > /* check for mandatory ops */
> > if (!mdev_driver->supported_type_groups)
> > return -EINVAL;
> >
> > - dev = get_device(dev);
> > - if (!dev)
> > - return -EINVAL;
> > -
> > - mutex_lock(&parent_list_lock);
> > -
> > - /* Check for duplicate */
> > - parent = __find_parent_device(dev);
> > - if (parent) {
> > - parent = NULL;
> > - ret = -EEXIST;
> > - goto add_dev_err;
> > - }
> > -
> > - parent = kzalloc(sizeof(*parent), GFP_KERNEL);
> > - if (!parent) {
> > - ret = -ENOMEM;
> > - goto add_dev_err;
> > - }
> > -
> > - kref_init(&parent->ref);
> > + memset(parent, 0, sizeof(*parent));
> > init_rwsem(&parent->unreg_sem);
> > -
> > parent->dev = dev;
> > parent->mdev_driver = mdev_driver;
> >
> > if (!mdev_bus_compat_class) {
> > mdev_bus_compat_class =
> > class_compat_register("mdev_bus");
> > - if (!mdev_bus_compat_class) {
> > - ret = -ENOMEM;
> > - goto add_dev_err;
> > - }
> > + if (!mdev_bus_compat_class)
> > + return -ENOMEM;
> > }
> >
> > ret = parent_create_sysfs_files(parent);
> > if (ret)
> > - goto add_dev_err;
> > + return ret;
> >
> > ret = class_compat_create_link(mdev_bus_compat_class, dev,
> > NULL);
> > if (ret)
> > dev_warn(dev, "Failed to create compatibility class
> > link\n");
> >
> > - list_add(&parent->next, &parent_list);
> > - mutex_unlock(&parent_list_lock);
> > -
> > dev_info(dev, "MDEV: Registered\n");
> > kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
> > -
> > return 0;
> > -
> > -add_dev_err:
> > - mutex_unlock(&parent_list_lock);
> > - if (parent)
> > - mdev_put_parent(parent);
> > - else
> > - put_device(dev);
> > - return ret;
> > }
> > -EXPORT_SYMBOL(mdev_register_device);
> > +EXPORT_SYMBOL(mdev_register_parent);
> >
> > /*
> > - * mdev_unregister_device : Unregister a parent device
> > - * @dev: device structure representing parent device.
> > - *
> > - * Remove device from list of registered parent devices. Give a
> > chance to free
> > - * existing mediated devices for given device.
> > + * mdev_unregister_parent : Unregister a parent device
> > + * @parent: parent structure to unregister
> > */
> > -
> > -void mdev_unregister_device(struct device *dev)
> > +void mdev_unregister_parent(struct mdev_parent *parent)
> > {
> > - struct mdev_parent *parent;
> > char *env_string = "MDEV_STATE=unregistered";
> > char *envp[] = { env_string, NULL };
> >
> > - mutex_lock(&parent_list_lock);
> > - parent = __find_parent_device(dev);
> > -
> > - if (!parent) {
> > - mutex_unlock(&parent_list_lock);
> > - return;
> > - }
> > - dev_info(dev, "MDEV: Unregistering\n");
> > -
> > - list_del(&parent->next);
> > - mutex_unlock(&parent_list_lock);
> > + dev_info(parent->dev, "MDEV: Unregistering\n");
> >
> > down_write(&parent->unreg_sem);
> > -
> > - class_compat_remove_link(mdev_bus_compat_class, dev, NULL);
> > -
> > - device_for_each_child(dev, NULL, mdev_device_remove_cb);
> > -
> > + class_compat_remove_link(mdev_bus_compat_class, parent->dev,
> > NULL);
> > + device_for_each_child(parent->dev, NULL,
> > mdev_device_remove_cb);
> > parent_remove_sysfs_files(parent);
> > up_write(&parent->unreg_sem);
> >
> > - mdev_put_parent(parent);
> > -
> > - /* We still have the caller's reference to use for the uevent
> > */
> > - kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
> > + kobject_uevent_env(&parent->dev->kobj, KOBJ_CHANGE, envp);
> > }
> > -EXPORT_SYMBOL(mdev_unregister_device);
> > +EXPORT_SYMBOL(mdev_unregister_parent);
> >
> > static void mdev_device_release(struct device *dev)
> > {
> > diff --git a/drivers/vfio/mdev/mdev_private.h
> > b/drivers/vfio/mdev/mdev_private.h
> > index 7c9fc79f3d838..297f911fdc890 100644
> > --- a/drivers/vfio/mdev/mdev_private.h
> > +++ b/drivers/vfio/mdev/mdev_private.h
> > @@ -13,17 +13,6 @@
> > int mdev_bus_register(void);
> > void mdev_bus_unregister(void);
> >
> > -struct mdev_parent {
> > - struct device *dev;
> > - struct mdev_driver *mdev_driver;
> > - struct kref ref;
> > - struct list_head next;
> > - struct kset *mdev_types_kset;
> > - struct list_head type_list;
> > - /* Synchronize device creation/removal with parent
> > unregistration */
> > - struct rw_semaphore unreg_sem;
> > -};
> > -
> > struct mdev_type {
> > struct kobject kobj;
> > struct kobject *devices_kobj;
> > @@ -48,16 +37,4 @@ void mdev_remove_sysfs_files(struct mdev_device
> > *mdev);
> > int mdev_device_create(struct mdev_type *kobj, const guid_t *uuid);
> > int mdev_device_remove(struct mdev_device *dev);
> >
> > -void mdev_release_parent(struct kref *kref);
> > -
> > -static inline void mdev_get_parent(struct mdev_parent *parent)
> > -{
> > - kref_get(&parent->ref);
> > -}
> > -
> > -static inline void mdev_put_parent(struct mdev_parent *parent)
> > -{
> > - kref_put(&parent->ref, mdev_release_parent);
> > -}
> > -
> > #endif /* MDEV_PRIVATE_H */
> > diff --git a/drivers/vfio/mdev/mdev_sysfs.c
> > b/drivers/vfio/mdev/mdev_sysfs.c
> > index 4bfbf49aaa66a..b71ffc5594870 100644
> > --- a/drivers/vfio/mdev/mdev_sysfs.c
> > +++ b/drivers/vfio/mdev/mdev_sysfs.c
> > @@ -81,7 +81,7 @@ static void mdev_type_release(struct kobject *kobj)
> >
> > pr_debug("Releasing group %s\n", kobj->name);
> > /* Pairs with the get in add_mdev_supported_type() */
> > - mdev_put_parent(type->parent);
> > + put_device(type->parent->dev);
> > kfree(type);
> > }
> >
> > @@ -110,7 +110,7 @@ static struct mdev_type
> > *add_mdev_supported_type(struct mdev_parent *parent,
> > type->kobj.kset = parent->mdev_types_kset;
> > type->parent = parent;
> > /* Pairs with the put in mdev_type_release() */
> > - mdev_get_parent(parent);
> > + get_device(parent->dev);
> > type->type_group_id = type_group_id;
> >
> > ret = kobject_init_and_add(&type->kobj, &mdev_type_ktype, NULL,
> > diff --git a/include/linux/mdev.h b/include/linux/mdev.h
> > index 555c1d015b5f0..327ce3e5c6b5f 100644
> > --- a/include/linux/mdev.h
> > +++ b/include/linux/mdev.h
> > @@ -23,6 +23,16 @@ struct mdev_device {
> > bool active;
> > };
> >
> > +/* embedded into the struct device that the mdev devices hang off */
> > +struct mdev_parent {
> > + struct device *dev;
> > + struct mdev_driver *mdev_driver;
> > + struct kset *mdev_types_kset;
> > + struct list_head type_list;
> > + /* Synchronize device creation/removal with parent
> > unregistration */
> > + struct rw_semaphore unreg_sem;
> > +};
> > +
> > static inline struct mdev_device *to_mdev_device(struct device *dev)
> > {
> > return container_of(dev, struct mdev_device, dev);
> > @@ -75,8 +85,9 @@ static inline const guid_t *mdev_uuid(struct
> > mdev_device *mdev)
> >
> > extern struct bus_type mdev_bus_type;
> >
> > -int mdev_register_device(struct device *dev, struct mdev_driver
> > *mdev_driver);
> > -void mdev_unregister_device(struct device *dev);
> > +int mdev_register_parent(struct mdev_parent *parent, struct device
> > *dev,
> > + struct mdev_driver *mdev_driver);
> > +void mdev_unregister_parent(struct mdev_parent *parent);
> >
> > int mdev_register_driver(struct mdev_driver *drv);
> > void mdev_unregister_driver(struct mdev_driver *drv);
> > diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c
> > index d0d1bb7747240..30b3643b3b389 100644
> > --- a/samples/vfio-mdev/mbochs.c
> > +++ b/samples/vfio-mdev/mbochs.c
> > @@ -128,6 +128,7 @@ static dev_t mbochs_devt;
> > static struct class *mbochs_class;
> > static struct cdev mbochs_cdev;
> > static struct device mbochs_dev;
> > +static struct mdev_parent mbochs_parent;
> > static atomic_t mbochs_avail_mbytes;
> > static const struct vfio_device_ops mbochs_dev_ops;
> >
> > @@ -1456,7 +1457,7 @@ static int __init mbochs_dev_init(void)
> > if (ret)
> > goto err_class;
> >
> > - ret = mdev_register_device(&mbochs_dev, &mbochs_driver);
> > + ret = mdev_register_parent(&mbochs_parent, &mbochs_dev,
> > &mbochs_driver);
> > if (ret)
> > goto err_device;
> >
> > @@ -1477,7 +1478,7 @@ static int __init mbochs_dev_init(void)
> > static void __exit mbochs_dev_exit(void)
> > {
> > mbochs_dev.bus = NULL;
> > - mdev_unregister_device(&mbochs_dev);
> > + mdev_unregister_parent(&mbochs_parent);
> >
> > device_unregister(&mbochs_dev);
> > mdev_unregister_driver(&mbochs_driver);
> > diff --git a/samples/vfio-mdev/mdpy.c b/samples/vfio-mdev/mdpy.c
> > index 0c4ca1f4be7ed..132bb055628a6 100644
> > --- a/samples/vfio-mdev/mdpy.c
> > +++ b/samples/vfio-mdev/mdpy.c
> > @@ -83,6 +83,7 @@ static dev_t mdpy_devt;
> > static struct class *mdpy_class;
> > static struct cdev mdpy_cdev;
> > static struct device mdpy_dev;
> > +static struct mdev_parent mdpy_parent;
> > static u32 mdpy_count;
> > static const struct vfio_device_ops mdpy_dev_ops;
> >
> > @@ -765,7 +766,7 @@ static int __init mdpy_dev_init(void)
> > if (ret)
> > goto err_class;
> >
> > - ret = mdev_register_device(&mdpy_dev, &mdpy_driver);
> > + ret = mdev_register_parent(&mdpy_parent, &mdpy_dev,
> > &mdpy_driver);
> > if (ret)
> > goto err_device;
> >
> > @@ -786,7 +787,7 @@ static int __init mdpy_dev_init(void)
> > static void __exit mdpy_dev_exit(void)
> > {
> > mdpy_dev.bus = NULL;
> > - mdev_unregister_device(&mdpy_dev);
> > + mdev_unregister_parent(&mdpy_parent);
> >
> > device_unregister(&mdpy_dev);
> > mdev_unregister_driver(&mdpy_driver);
> > diff --git a/samples/vfio-mdev/mtty.c b/samples/vfio-mdev/mtty.c
> > index 4f5a6f2d3629d..8ba5f6084a093 100644
> > --- a/samples/vfio-mdev/mtty.c
> > +++ b/samples/vfio-mdev/mtty.c
> > @@ -72,6 +72,7 @@ static struct mtty_dev {
> > struct cdev vd_cdev;
> > struct idr vd_idr;
> > struct device dev;
> > + struct mdev_parent parent;
> > } mtty_dev;
> >
> > struct mdev_region_info {
> > @@ -1350,7 +1351,8 @@ static int __init mtty_dev_init(void)
> > if (ret)
> > goto err_class;
> >
> > - ret = mdev_register_device(&mtty_dev.dev, &mtty_driver);
> > + ret = mdev_register_parent(&mtty_dev.parent, &mtty_dev.dev,
> > + &mtty_driver);
> > if (ret)
> > goto err_device;
> > return 0;
> > @@ -1370,7 +1372,7 @@ static int __init mtty_dev_init(void)
> > static void __exit mtty_dev_exit(void)
> > {
> > mtty_dev.dev.bus = NULL;
> > - mdev_unregister_device(&mtty_dev.dev);
> > + mdev_unregister_parent(&mtty_dev.parent);
> >
> > device_unregister(&mtty_dev.dev);
> > idr_destroy(&mtty_dev.vd_idr);
>
^ permalink raw reply [flat|nested] 31+ messages in thread
* Re: [PATCH 15/15] vfio/mdev: remove an extra parent kobject reference
2022-07-06 13:48 ` Kirti Wankhede
@ 2022-07-07 13:37 ` Christoph Hellwig
0 siblings, 0 replies; 31+ messages in thread
From: Christoph Hellwig @ 2022-07-07 13:37 UTC (permalink / raw)
To: Kirti Wankhede
Cc: Christoph Hellwig, Tony Krowiak, Halil Pasic, Jason Herne,
Eric Farman, Matthew Rosato, Zhenyu Wang, Zhi Wang,
Alex Williamson, Jason Gunthorpe, kvm, linux-s390, intel-gvt-dev,
Tarun Gupta, Neo Jia, Shounak Deshpande
On Wed, Jul 06, 2022 at 07:18:48PM +0530, Kirti Wankhede wrote:
>> - kobject_put(&type->kobj);
>
> This kobject_put is required here in error case, see description above
> kobject_init_and_add().
And they are completely unrelated anyway, this should have never slipped
in.
^ permalink raw reply [flat|nested] 31+ messages in thread
* Re: [PATCH 04/15] vfio/mdev: embedd struct mdev_parent in the parent data structure
2022-07-07 7:22 ` Vineeth Vijayan
@ 2022-07-07 13:40 ` Christoph Hellwig
0 siblings, 0 replies; 31+ messages in thread
From: Christoph Hellwig @ 2022-07-07 13:40 UTC (permalink / raw)
To: Vineeth Vijayan
Cc: Eric Farman, Christoph Hellwig, Kirti Wankhede, Tony Krowiak,
Halil Pasic, Jason Herne, Matthew Rosato, Zhenyu Wang, Zhi Wang,
Alex Williamson, Peter Oberparleiter, Jason Gunthorpe, kvm,
linux-s390, intel-gvt-dev, Kevin Tian
On Thu, Jul 07, 2022 at 09:22:21AM +0200, Vineeth Vijayan wrote:
> Thank you Eric for pointing it out. You are right. I think the struct
> subchannel is obviously the wrong place.
> Also, in this case, the mdev_parent should be in one of the vfio-ccw
> io-subchannel structure, which as you mentioned should be in vfio-ccw*.
It is where the parent dev is embedded into, so it sticks to the
spirit of the old code. I'm totally fine with you guys moving it
to another structure of your choice, but for making progress on this
series it should be good enough.
^ permalink raw reply [flat|nested] 31+ messages in thread
* Re: [PATCH 15/15] vfio/mdev: remove an extra parent kobject reference
2022-07-06 14:38 ` Jason Gunthorpe
@ 2022-07-07 13:40 ` Christoph Hellwig
2022-07-07 23:01 ` Alex Williamson
0 siblings, 1 reply; 31+ messages in thread
From: Christoph Hellwig @ 2022-07-07 13:40 UTC (permalink / raw)
To: Jason Gunthorpe
Cc: Christoph Hellwig, Kirti Wankhede, Tony Krowiak, Halil Pasic,
Jason Herne, Eric Farman, Matthew Rosato, Zhenyu Wang, Zhi Wang,
Alex Williamson, kvm, linux-s390, intel-gvt-dev
On Wed, Jul 06, 2022 at 11:38:33AM -0300, Jason Gunthorpe wrote:
> On Wed, Jul 06, 2022 at 09:42:19AM +0200, Christoph Hellwig wrote:
> > The mdev_type already holds a reference to the parent through
> > mdev_types_kset, so drop the extra reference.
>
> I would drop this patch, but at least the explanation needs tweaking..
I'm fine with that. Alex, any preferences?
^ permalink raw reply [flat|nested] 31+ messages in thread
* Re: [PATCH 15/15] vfio/mdev: remove an extra parent kobject reference
2022-07-07 13:40 ` Christoph Hellwig
@ 2022-07-07 23:01 ` Alex Williamson
0 siblings, 0 replies; 31+ messages in thread
From: Alex Williamson @ 2022-07-07 23:01 UTC (permalink / raw)
To: Christoph Hellwig
Cc: Jason Gunthorpe, Kirti Wankhede, Tony Krowiak, Halil Pasic,
Jason Herne, Eric Farman, Matthew Rosato, Zhenyu Wang, Zhi Wang,
kvm, linux-s390, intel-gvt-dev
On Thu, 7 Jul 2022 15:40:52 +0200
Christoph Hellwig <hch@lst.de> wrote:
> On Wed, Jul 06, 2022 at 11:38:33AM -0300, Jason Gunthorpe wrote:
> > On Wed, Jul 06, 2022 at 09:42:19AM +0200, Christoph Hellwig wrote:
> > > The mdev_type already holds a reference to the parent through
> > > mdev_types_kset, so drop the extra reference.
> >
> > I would drop this patch, but at least the explanation needs tweaking..
>
> I'm fine with that. Alex, any preferences?
Modulo the bogus kobject_put()s, this essentially reverts:
commit 9a302449a58d45d0ef2aab686f64b35919bc604c
Author: Jason Gunthorpe <jgg@ziepe.ca>
Date: Tue Apr 6 16:40:30 2021 -0300
vfio/mdev: Add missing reference counting to mdev_type
struct mdev_type holds a pointer to the kref'd object struct mdev_parent,
but doesn't hold the kref. The lifetime of the parent becomes implicit
because parent_remove_sysfs_files() is supposed to remove all the access
before the parent can be freed, but this is very hard to reason about.
Make it obviously correct by adding the missing get.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Message-Id: <7-v2-d36939638fc6+d54-vfio2_jgg@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Which we all seemed to think was a good thing 15 months ago. It is
still difficult to reason when the mdev_type_ktype.release function
occurs relative to the parent reference held by the kset, but without
an explanation how we're safe, I'm ok with a little paranoia and
explicit references. Thanks,
Alex
^ permalink raw reply [flat|nested] 31+ messages in thread
* Re: [PATCH 14/15] vfio/mdev: add mdev available instance checking to the core
2022-07-07 3:08 ` Eric Farman
@ 2022-07-08 5:48 ` Christoph Hellwig
0 siblings, 0 replies; 31+ messages in thread
From: Christoph Hellwig @ 2022-07-08 5:48 UTC (permalink / raw)
To: Eric Farman
Cc: Christoph Hellwig, Kirti Wankhede, Tony Krowiak, Halil Pasic,
Jason Herne, Matthew Rosato, Zhenyu Wang, Zhi Wang,
Alex Williamson, Jason Gunthorpe, kvm, linux-s390, intel-gvt-dev,
Kevin Tian
On Wed, Jul 06, 2022 at 11:08:57PM -0400, Eric Farman wrote:
> If I read this right, .get_available and .max_instances are mutually
> exclusive.
Yes.
> Which means that available_instances_show() from patch 12
> would need to emit parent->available_instances if .get_available is
> NULL.
Indeed.
^ permalink raw reply [flat|nested] 31+ messages in thread
end of thread, other threads:[~2022-07-08 5:48 UTC | newest]
Thread overview: 31+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-07-06 7:42 simplify the mdev interface v5 Christoph Hellwig
2022-07-06 7:42 ` [PATCH 01/15] drm/i915/gvt: fix a memory leak in intel_gvt_init_vgpu_types Christoph Hellwig
2022-07-06 7:42 ` [PATCH 02/15] drm/i915/gvt: simplify vgpu configuration management Christoph Hellwig
2022-07-07 2:18 ` Tian, Kevin
2022-07-06 7:42 ` [PATCH 03/15] vfio/mdev: make mdev.h standalone includable Christoph Hellwig
2022-07-06 7:42 ` [PATCH 04/15] vfio/mdev: embedd struct mdev_parent in the parent data structure Christoph Hellwig
2022-07-06 13:29 ` Kirti Wankhede
2022-07-07 3:08 ` Eric Farman
2022-07-07 7:22 ` Vineeth Vijayan
2022-07-07 13:40 ` Christoph Hellwig
2022-07-06 7:42 ` [PATCH 05/15] vfio/mdev: simplify mdev_type handling Christoph Hellwig
2022-07-06 13:31 ` Kirti Wankhede
2022-07-06 7:42 ` [PATCH 06/15] vfio/mdev: remove mdev_from_dev Christoph Hellwig
2022-07-06 7:42 ` [PATCH 07/15] vfio/mdev: unexport mdev_bus_type Christoph Hellwig
2022-07-06 7:42 ` [PATCH 08/15] vfio/mdev: remove mdev_parent_dev Christoph Hellwig
2022-07-06 7:42 ` [PATCH 09/15] vfio/mdev: remove mtype_get_parent_dev Christoph Hellwig
2022-07-06 7:42 ` [PATCH 10/15] vfio/mdev: consolidate all the device_api sysfs into the core code Christoph Hellwig
2022-07-06 7:42 ` [PATCH 11/15] vfio/mdev: consolidate all the name " Christoph Hellwig
2022-07-06 7:42 ` [PATCH 12/15] vfio/mdev: consolidate all the available_instance " Christoph Hellwig
2022-07-06 7:42 ` [PATCH 13/15] vfio/mdev: consolidate all the description " Christoph Hellwig
2022-07-06 7:42 ` [PATCH 14/15] vfio/mdev: add mdev available instance checking to the core Christoph Hellwig
2022-07-06 13:37 ` Kirti Wankhede
2022-07-07 3:08 ` Eric Farman
2022-07-08 5:48 ` Christoph Hellwig
2022-07-06 7:42 ` [PATCH 15/15] vfio/mdev: remove an extra parent kobject reference Christoph Hellwig
2022-07-06 13:48 ` Kirti Wankhede
2022-07-07 13:37 ` Christoph Hellwig
2022-07-06 14:38 ` Jason Gunthorpe
2022-07-07 13:40 ` Christoph Hellwig
2022-07-07 23:01 ` Alex Williamson
2022-07-07 2:19 ` Tian, Kevin
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