* [PATCH v15 01/12] swiotlb: Refactor swiotlb init functions
2021-06-24 15:55 [PATCH v15 00/12] Restricted DMA Claire Chang
@ 2021-06-24 15:55 ` Claire Chang
2021-06-24 15:55 ` [PATCH v15 02/12] swiotlb: Refactor swiotlb_create_debugfs Claire Chang
` (11 subsequent siblings)
12 siblings, 0 replies; 44+ messages in thread
From: Claire Chang @ 2021-06-24 15:55 UTC (permalink / raw)
To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross,
Christoph Hellwig, Marek Szyprowski
Cc: benh, paulus, list@263.net:IOMMU DRIVERS, sstabellini,
Robin Murphy, grant.likely, xypron.glpk, Thierry Reding, mingo,
bauerman, peterz, Greg KH, Saravana Kannan, Rafael J . Wysocki,
heikki.krogerus, Andy Shevchenko, Randy Dunlap, Dan Williams,
Bartosz Golaszewski, linux-devicetree, lkml, linuxppc-dev,
xen-devel, Nicolas Boichat, Jim Quinlan, tfiga, bskeggs,
bhelgaas, chris, tientzu, daniel, airlied, dri-devel, intel-gfx,
jani.nikula, jxgao, joonas.lahtinen, linux-pci,
maarten.lankhorst, matthew.auld, rodrigo.vivi, thomas.hellstrom,
thomas.lendacky, quic_qiancai
Add a new function, swiotlb_init_io_tlb_mem, for the io_tlb_mem struct
initialization to make the code reusable.
Signed-off-by: Claire Chang <tientzu@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Stefano Stabellini <sstabellini@kernel.org>
Tested-by: Will Deacon <will@kernel.org>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
---
kernel/dma/swiotlb.c | 50 ++++++++++++++++++++++----------------------
1 file changed, 25 insertions(+), 25 deletions(-)
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 52e2ac526757..1f9b2b9e7490 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -168,9 +168,28 @@ void __init swiotlb_update_mem_attributes(void)
memset(vaddr, 0, bytes);
}
-int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose)
+static void swiotlb_init_io_tlb_mem(struct io_tlb_mem *mem, phys_addr_t start,
+ unsigned long nslabs, bool late_alloc)
{
+ void *vaddr = phys_to_virt(start);
unsigned long bytes = nslabs << IO_TLB_SHIFT, i;
+
+ mem->nslabs = nslabs;
+ mem->start = start;
+ mem->end = mem->start + bytes;
+ mem->index = 0;
+ mem->late_alloc = late_alloc;
+ spin_lock_init(&mem->lock);
+ for (i = 0; i < mem->nslabs; i++) {
+ mem->slots[i].list = IO_TLB_SEGSIZE - io_tlb_offset(i);
+ mem->slots[i].orig_addr = INVALID_PHYS_ADDR;
+ mem->slots[i].alloc_size = 0;
+ }
+ memset(vaddr, 0, bytes);
+}
+
+int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose)
+{
struct io_tlb_mem *mem;
size_t alloc_size;
@@ -186,16 +205,8 @@ int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose)
if (!mem)
panic("%s: Failed to allocate %zu bytes align=0x%lx\n",
__func__, alloc_size, PAGE_SIZE);
- mem->nslabs = nslabs;
- mem->start = __pa(tlb);
- mem->end = mem->start + bytes;
- mem->index = 0;
- spin_lock_init(&mem->lock);
- for (i = 0; i < mem->nslabs; i++) {
- mem->slots[i].list = IO_TLB_SEGSIZE - io_tlb_offset(i);
- mem->slots[i].orig_addr = INVALID_PHYS_ADDR;
- mem->slots[i].alloc_size = 0;
- }
+
+ swiotlb_init_io_tlb_mem(mem, __pa(tlb), nslabs, false);
io_tlb_default_mem = mem;
if (verbose)
@@ -282,8 +293,8 @@ swiotlb_late_init_with_default_size(size_t default_size)
int
swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs)
{
- unsigned long bytes = nslabs << IO_TLB_SHIFT, i;
struct io_tlb_mem *mem;
+ unsigned long bytes = nslabs << IO_TLB_SHIFT;
if (swiotlb_force == SWIOTLB_NO_FORCE)
return 0;
@@ -297,20 +308,9 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs)
if (!mem)
return -ENOMEM;
- mem->nslabs = nslabs;
- mem->start = virt_to_phys(tlb);
- mem->end = mem->start + bytes;
- mem->index = 0;
- mem->late_alloc = 1;
- spin_lock_init(&mem->lock);
- for (i = 0; i < mem->nslabs; i++) {
- mem->slots[i].list = IO_TLB_SEGSIZE - io_tlb_offset(i);
- mem->slots[i].orig_addr = INVALID_PHYS_ADDR;
- mem->slots[i].alloc_size = 0;
- }
-
+ memset(mem, 0, sizeof(*mem));
set_memory_decrypted((unsigned long)tlb, bytes >> PAGE_SHIFT);
- memset(tlb, 0, bytes);
+ swiotlb_init_io_tlb_mem(mem, virt_to_phys(tlb), nslabs, true);
io_tlb_default_mem = mem;
swiotlb_print_info();
--
2.32.0.288.g62a8d224e6-goog
^ permalink raw reply related [flat|nested] 44+ messages in thread
* [PATCH v15 02/12] swiotlb: Refactor swiotlb_create_debugfs
2021-06-24 15:55 [PATCH v15 00/12] Restricted DMA Claire Chang
2021-06-24 15:55 ` [PATCH v15 01/12] swiotlb: Refactor swiotlb init functions Claire Chang
@ 2021-06-24 15:55 ` Claire Chang
2021-06-24 15:55 ` [PATCH v15 03/12] swiotlb: Set dev->dma_io_tlb_mem to the swiotlb pool used Claire Chang
` (10 subsequent siblings)
12 siblings, 0 replies; 44+ messages in thread
From: Claire Chang @ 2021-06-24 15:55 UTC (permalink / raw)
To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross,
Christoph Hellwig, Marek Szyprowski
Cc: benh, paulus, list@263.net:IOMMU DRIVERS, sstabellini,
Robin Murphy, grant.likely, xypron.glpk, Thierry Reding, mingo,
bauerman, peterz, Greg KH, Saravana Kannan, Rafael J . Wysocki,
heikki.krogerus, Andy Shevchenko, Randy Dunlap, Dan Williams,
Bartosz Golaszewski, linux-devicetree, lkml, linuxppc-dev,
xen-devel, Nicolas Boichat, Jim Quinlan, tfiga, bskeggs,
bhelgaas, chris, tientzu, daniel, airlied, dri-devel, intel-gfx,
jani.nikula, jxgao, joonas.lahtinen, linux-pci,
maarten.lankhorst, matthew.auld, rodrigo.vivi, thomas.hellstrom,
thomas.lendacky, quic_qiancai
Split the debugfs creation to make the code reusable for supporting
different bounce buffer pools.
Signed-off-by: Claire Chang <tientzu@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Stefano Stabellini <sstabellini@kernel.org>
Tested-by: Will Deacon <will@kernel.org>
---
kernel/dma/swiotlb.c | 21 ++++++++++++++-------
1 file changed, 14 insertions(+), 7 deletions(-)
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 1f9b2b9e7490..ede66df6835b 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -671,19 +671,26 @@ bool is_swiotlb_active(void)
EXPORT_SYMBOL_GPL(is_swiotlb_active);
#ifdef CONFIG_DEBUG_FS
+static struct dentry *debugfs_dir;
-static int __init swiotlb_create_debugfs(void)
+static void swiotlb_create_debugfs_files(struct io_tlb_mem *mem)
{
- struct io_tlb_mem *mem = io_tlb_default_mem;
-
- if (!mem)
- return 0;
- mem->debugfs = debugfs_create_dir("swiotlb", NULL);
debugfs_create_ulong("io_tlb_nslabs", 0400, mem->debugfs, &mem->nslabs);
debugfs_create_ulong("io_tlb_used", 0400, mem->debugfs, &mem->used);
+}
+
+static int __init swiotlb_create_default_debugfs(void)
+{
+ struct io_tlb_mem *mem = io_tlb_default_mem;
+
+ debugfs_dir = debugfs_create_dir("swiotlb", NULL);
+ if (mem) {
+ mem->debugfs = debugfs_dir;
+ swiotlb_create_debugfs_files(mem);
+ }
return 0;
}
-late_initcall(swiotlb_create_debugfs);
+late_initcall(swiotlb_create_default_debugfs);
#endif
--
2.32.0.288.g62a8d224e6-goog
^ permalink raw reply related [flat|nested] 44+ messages in thread
* [PATCH v15 03/12] swiotlb: Set dev->dma_io_tlb_mem to the swiotlb pool used
2021-06-24 15:55 [PATCH v15 00/12] Restricted DMA Claire Chang
2021-06-24 15:55 ` [PATCH v15 01/12] swiotlb: Refactor swiotlb init functions Claire Chang
2021-06-24 15:55 ` [PATCH v15 02/12] swiotlb: Refactor swiotlb_create_debugfs Claire Chang
@ 2021-06-24 15:55 ` Claire Chang
2021-06-24 15:55 ` [PATCH v15 04/12] swiotlb: Update is_swiotlb_buffer to add a struct device argument Claire Chang
` (9 subsequent siblings)
12 siblings, 0 replies; 44+ messages in thread
From: Claire Chang @ 2021-06-24 15:55 UTC (permalink / raw)
To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross,
Christoph Hellwig, Marek Szyprowski
Cc: benh, paulus, list@263.net:IOMMU DRIVERS, sstabellini,
Robin Murphy, grant.likely, xypron.glpk, Thierry Reding, mingo,
bauerman, peterz, Greg KH, Saravana Kannan, Rafael J . Wysocki,
heikki.krogerus, Andy Shevchenko, Randy Dunlap, Dan Williams,
Bartosz Golaszewski, linux-devicetree, lkml, linuxppc-dev,
xen-devel, Nicolas Boichat, Jim Quinlan, tfiga, bskeggs,
bhelgaas, chris, tientzu, daniel, airlied, dri-devel, intel-gfx,
jani.nikula, jxgao, joonas.lahtinen, linux-pci,
maarten.lankhorst, matthew.auld, rodrigo.vivi, thomas.hellstrom,
thomas.lendacky, quic_qiancai
Always have the pointer to the swiotlb pool used in struct device. This
could help simplify the code for other pools.
Signed-off-by: Claire Chang <tientzu@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Stefano Stabellini <sstabellini@kernel.org>
Tested-by: Will Deacon <will@kernel.org>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
---
drivers/base/core.c | 4 ++++
include/linux/device.h | 4 ++++
kernel/dma/swiotlb.c | 8 ++++----
3 files changed, 12 insertions(+), 4 deletions(-)
diff --git a/drivers/base/core.c b/drivers/base/core.c
index f29839382f81..cb3123e3954d 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -27,6 +27,7 @@
#include <linux/netdevice.h>
#include <linux/sched/signal.h>
#include <linux/sched/mm.h>
+#include <linux/swiotlb.h>
#include <linux/sysfs.h>
#include <linux/dma-map-ops.h> /* for dma_default_coherent */
@@ -2736,6 +2737,9 @@ void device_initialize(struct device *dev)
defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL)
dev->dma_coherent = dma_default_coherent;
#endif
+#ifdef CONFIG_SWIOTLB
+ dev->dma_io_tlb_mem = io_tlb_default_mem;
+#endif
}
EXPORT_SYMBOL_GPL(device_initialize);
diff --git a/include/linux/device.h b/include/linux/device.h
index ba660731bd25..240d652a0696 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -416,6 +416,7 @@ struct dev_links_info {
* @dma_pools: Dma pools (if dma'ble device).
* @dma_mem: Internal for coherent mem override.
* @cma_area: Contiguous memory area for dma allocations
+ * @dma_io_tlb_mem: Pointer to the swiotlb pool used. Not for driver use.
* @archdata: For arch-specific additions.
* @of_node: Associated device tree node.
* @fwnode: Associated device node supplied by platform firmware.
@@ -518,6 +519,9 @@ struct device {
#ifdef CONFIG_DMA_CMA
struct cma *cma_area; /* contiguous memory area for dma
allocations */
+#endif
+#ifdef CONFIG_SWIOTLB
+ struct io_tlb_mem *dma_io_tlb_mem;
#endif
/* arch specific additions */
struct dev_archdata archdata;
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index ede66df6835b..72a4289faed1 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -340,7 +340,7 @@ void __init swiotlb_exit(void)
static void swiotlb_bounce(struct device *dev, phys_addr_t tlb_addr, size_t size,
enum dma_data_direction dir)
{
- struct io_tlb_mem *mem = io_tlb_default_mem;
+ struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
int index = (tlb_addr - mem->start) >> IO_TLB_SHIFT;
unsigned int offset = (tlb_addr - mem->start) & (IO_TLB_SIZE - 1);
phys_addr_t orig_addr = mem->slots[index].orig_addr;
@@ -431,7 +431,7 @@ static unsigned int wrap_index(struct io_tlb_mem *mem, unsigned int index)
static int find_slots(struct device *dev, phys_addr_t orig_addr,
size_t alloc_size)
{
- struct io_tlb_mem *mem = io_tlb_default_mem;
+ struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
unsigned long boundary_mask = dma_get_seg_boundary(dev);
dma_addr_t tbl_dma_addr =
phys_to_dma_unencrypted(dev, mem->start) & boundary_mask;
@@ -508,7 +508,7 @@ phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr,
size_t mapping_size, size_t alloc_size,
enum dma_data_direction dir, unsigned long attrs)
{
- struct io_tlb_mem *mem = io_tlb_default_mem;
+ struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
unsigned int offset = swiotlb_align_offset(dev, orig_addr);
unsigned int i;
int index;
@@ -559,7 +559,7 @@ void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr,
size_t mapping_size, enum dma_data_direction dir,
unsigned long attrs)
{
- struct io_tlb_mem *mem = io_tlb_default_mem;
+ struct io_tlb_mem *mem = hwdev->dma_io_tlb_mem;
unsigned long flags;
unsigned int offset = swiotlb_align_offset(hwdev, tlb_addr);
int index = (tlb_addr - offset - mem->start) >> IO_TLB_SHIFT;
--
2.32.0.288.g62a8d224e6-goog
^ permalink raw reply related [flat|nested] 44+ messages in thread
* [PATCH v15 04/12] swiotlb: Update is_swiotlb_buffer to add a struct device argument
2021-06-24 15:55 [PATCH v15 00/12] Restricted DMA Claire Chang
` (2 preceding siblings ...)
2021-06-24 15:55 ` [PATCH v15 03/12] swiotlb: Set dev->dma_io_tlb_mem to the swiotlb pool used Claire Chang
@ 2021-06-24 15:55 ` Claire Chang
2021-06-24 15:55 ` [PATCH v15 05/12] swiotlb: Update is_swiotlb_active " Claire Chang
` (8 subsequent siblings)
12 siblings, 0 replies; 44+ messages in thread
From: Claire Chang @ 2021-06-24 15:55 UTC (permalink / raw)
To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross,
Christoph Hellwig, Marek Szyprowski
Cc: benh, paulus, list@263.net:IOMMU DRIVERS, sstabellini,
Robin Murphy, grant.likely, xypron.glpk, Thierry Reding, mingo,
bauerman, peterz, Greg KH, Saravana Kannan, Rafael J . Wysocki,
heikki.krogerus, Andy Shevchenko, Randy Dunlap, Dan Williams,
Bartosz Golaszewski, linux-devicetree, lkml, linuxppc-dev,
xen-devel, Nicolas Boichat, Jim Quinlan, tfiga, bskeggs,
bhelgaas, chris, tientzu, daniel, airlied, dri-devel, intel-gfx,
jani.nikula, jxgao, joonas.lahtinen, linux-pci,
maarten.lankhorst, matthew.auld, rodrigo.vivi, thomas.hellstrom,
thomas.lendacky, quic_qiancai
Update is_swiotlb_buffer to add a struct device argument. This will be
useful later to allow for different pools.
Signed-off-by: Claire Chang <tientzu@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Stefano Stabellini <sstabellini@kernel.org>
Tested-by: Will Deacon <will@kernel.org>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
---
drivers/iommu/dma-iommu.c | 12 ++++++------
drivers/xen/swiotlb-xen.c | 2 +-
include/linux/swiotlb.h | 7 ++++---
kernel/dma/direct.c | 6 +++---
kernel/dma/direct.h | 6 +++---
5 files changed, 17 insertions(+), 16 deletions(-)
diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index 3087d9fa6065..10997ef541f8 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -507,7 +507,7 @@ static void __iommu_dma_unmap_swiotlb(struct device *dev, dma_addr_t dma_addr,
__iommu_dma_unmap(dev, dma_addr, size);
- if (unlikely(is_swiotlb_buffer(phys)))
+ if (unlikely(is_swiotlb_buffer(dev, phys)))
swiotlb_tbl_unmap_single(dev, phys, size, dir, attrs);
}
@@ -578,7 +578,7 @@ static dma_addr_t __iommu_dma_map_swiotlb(struct device *dev, phys_addr_t phys,
}
iova = __iommu_dma_map(dev, phys, aligned_size, prot, dma_mask);
- if (iova == DMA_MAPPING_ERROR && is_swiotlb_buffer(phys))
+ if (iova == DMA_MAPPING_ERROR && is_swiotlb_buffer(dev, phys))
swiotlb_tbl_unmap_single(dev, phys, org_size, dir, attrs);
return iova;
}
@@ -749,7 +749,7 @@ static void iommu_dma_sync_single_for_cpu(struct device *dev,
if (!dev_is_dma_coherent(dev))
arch_sync_dma_for_cpu(phys, size, dir);
- if (is_swiotlb_buffer(phys))
+ if (is_swiotlb_buffer(dev, phys))
swiotlb_sync_single_for_cpu(dev, phys, size, dir);
}
@@ -762,7 +762,7 @@ static void iommu_dma_sync_single_for_device(struct device *dev,
return;
phys = iommu_iova_to_phys(iommu_get_dma_domain(dev), dma_handle);
- if (is_swiotlb_buffer(phys))
+ if (is_swiotlb_buffer(dev, phys))
swiotlb_sync_single_for_device(dev, phys, size, dir);
if (!dev_is_dma_coherent(dev))
@@ -783,7 +783,7 @@ static void iommu_dma_sync_sg_for_cpu(struct device *dev,
if (!dev_is_dma_coherent(dev))
arch_sync_dma_for_cpu(sg_phys(sg), sg->length, dir);
- if (is_swiotlb_buffer(sg_phys(sg)))
+ if (is_swiotlb_buffer(dev, sg_phys(sg)))
swiotlb_sync_single_for_cpu(dev, sg_phys(sg),
sg->length, dir);
}
@@ -800,7 +800,7 @@ static void iommu_dma_sync_sg_for_device(struct device *dev,
return;
for_each_sg(sgl, sg, nelems, i) {
- if (is_swiotlb_buffer(sg_phys(sg)))
+ if (is_swiotlb_buffer(dev, sg_phys(sg)))
swiotlb_sync_single_for_device(dev, sg_phys(sg),
sg->length, dir);
diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c
index 4c89afc0df62..0c6ed09f8513 100644
--- a/drivers/xen/swiotlb-xen.c
+++ b/drivers/xen/swiotlb-xen.c
@@ -100,7 +100,7 @@ static int is_xen_swiotlb_buffer(struct device *dev, dma_addr_t dma_addr)
* in our domain. Therefore _only_ check address within our domain.
*/
if (pfn_valid(PFN_DOWN(paddr)))
- return is_swiotlb_buffer(paddr);
+ return is_swiotlb_buffer(dev, paddr);
return 0;
}
diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index 216854a5e513..d1f3d95881cd 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -2,6 +2,7 @@
#ifndef __LINUX_SWIOTLB_H
#define __LINUX_SWIOTLB_H
+#include <linux/device.h>
#include <linux/dma-direction.h>
#include <linux/init.h>
#include <linux/types.h>
@@ -101,9 +102,9 @@ struct io_tlb_mem {
};
extern struct io_tlb_mem *io_tlb_default_mem;
-static inline bool is_swiotlb_buffer(phys_addr_t paddr)
+static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr)
{
- struct io_tlb_mem *mem = io_tlb_default_mem;
+ struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
return mem && paddr >= mem->start && paddr < mem->end;
}
@@ -115,7 +116,7 @@ bool is_swiotlb_active(void);
void __init swiotlb_adjust_size(unsigned long size);
#else
#define swiotlb_force SWIOTLB_NO_FORCE
-static inline bool is_swiotlb_buffer(phys_addr_t paddr)
+static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr)
{
return false;
}
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index f737e3347059..84c9feb5474a 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -343,7 +343,7 @@ void dma_direct_sync_sg_for_device(struct device *dev,
for_each_sg(sgl, sg, nents, i) {
phys_addr_t paddr = dma_to_phys(dev, sg_dma_address(sg));
- if (unlikely(is_swiotlb_buffer(paddr)))
+ if (unlikely(is_swiotlb_buffer(dev, paddr)))
swiotlb_sync_single_for_device(dev, paddr, sg->length,
dir);
@@ -369,7 +369,7 @@ void dma_direct_sync_sg_for_cpu(struct device *dev,
if (!dev_is_dma_coherent(dev))
arch_sync_dma_for_cpu(paddr, sg->length, dir);
- if (unlikely(is_swiotlb_buffer(paddr)))
+ if (unlikely(is_swiotlb_buffer(dev, paddr)))
swiotlb_sync_single_for_cpu(dev, paddr, sg->length,
dir);
@@ -504,7 +504,7 @@ size_t dma_direct_max_mapping_size(struct device *dev)
bool dma_direct_need_sync(struct device *dev, dma_addr_t dma_addr)
{
return !dev_is_dma_coherent(dev) ||
- is_swiotlb_buffer(dma_to_phys(dev, dma_addr));
+ is_swiotlb_buffer(dev, dma_to_phys(dev, dma_addr));
}
/**
diff --git a/kernel/dma/direct.h b/kernel/dma/direct.h
index 50afc05b6f1d..13e9e7158d94 100644
--- a/kernel/dma/direct.h
+++ b/kernel/dma/direct.h
@@ -56,7 +56,7 @@ static inline void dma_direct_sync_single_for_device(struct device *dev,
{
phys_addr_t paddr = dma_to_phys(dev, addr);
- if (unlikely(is_swiotlb_buffer(paddr)))
+ if (unlikely(is_swiotlb_buffer(dev, paddr)))
swiotlb_sync_single_for_device(dev, paddr, size, dir);
if (!dev_is_dma_coherent(dev))
@@ -73,7 +73,7 @@ static inline void dma_direct_sync_single_for_cpu(struct device *dev,
arch_sync_dma_for_cpu_all();
}
- if (unlikely(is_swiotlb_buffer(paddr)))
+ if (unlikely(is_swiotlb_buffer(dev, paddr)))
swiotlb_sync_single_for_cpu(dev, paddr, size, dir);
if (dir == DMA_FROM_DEVICE)
@@ -113,7 +113,7 @@ static inline void dma_direct_unmap_page(struct device *dev, dma_addr_t addr,
if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
dma_direct_sync_single_for_cpu(dev, addr, size, dir);
- if (unlikely(is_swiotlb_buffer(phys)))
+ if (unlikely(is_swiotlb_buffer(dev, phys)))
swiotlb_tbl_unmap_single(dev, phys, size, dir, attrs);
}
#endif /* _KERNEL_DMA_DIRECT_H */
--
2.32.0.288.g62a8d224e6-goog
^ permalink raw reply related [flat|nested] 44+ messages in thread
* [PATCH v15 05/12] swiotlb: Update is_swiotlb_active to add a struct device argument
2021-06-24 15:55 [PATCH v15 00/12] Restricted DMA Claire Chang
` (3 preceding siblings ...)
2021-06-24 15:55 ` [PATCH v15 04/12] swiotlb: Update is_swiotlb_buffer to add a struct device argument Claire Chang
@ 2021-06-24 15:55 ` Claire Chang
2021-06-24 15:55 ` [PATCH v15 06/12] swiotlb: Use is_swiotlb_force_bounce for swiotlb data bouncing Claire Chang
` (7 subsequent siblings)
12 siblings, 0 replies; 44+ messages in thread
From: Claire Chang @ 2021-06-24 15:55 UTC (permalink / raw)
To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross,
Christoph Hellwig, Marek Szyprowski
Cc: benh, paulus, list@263.net:IOMMU DRIVERS, sstabellini,
Robin Murphy, grant.likely, xypron.glpk, Thierry Reding, mingo,
bauerman, peterz, Greg KH, Saravana Kannan, Rafael J . Wysocki,
heikki.krogerus, Andy Shevchenko, Randy Dunlap, Dan Williams,
Bartosz Golaszewski, linux-devicetree, lkml, linuxppc-dev,
xen-devel, Nicolas Boichat, Jim Quinlan, tfiga, bskeggs,
bhelgaas, chris, tientzu, daniel, airlied, dri-devel, intel-gfx,
jani.nikula, jxgao, joonas.lahtinen, linux-pci,
maarten.lankhorst, matthew.auld, rodrigo.vivi, thomas.hellstrom,
thomas.lendacky, quic_qiancai
Update is_swiotlb_active to add a struct device argument. This will be
useful later to allow for different pools.
Signed-off-by: Claire Chang <tientzu@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Stefano Stabellini <sstabellini@kernel.org>
Tested-by: Will Deacon <will@kernel.org>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
---
drivers/gpu/drm/i915/gem/i915_gem_internal.c | 2 +-
drivers/gpu/drm/nouveau/nouveau_ttm.c | 2 +-
drivers/pci/xen-pcifront.c | 2 +-
include/linux/swiotlb.h | 4 ++--
kernel/dma/direct.c | 2 +-
kernel/dma/swiotlb.c | 4 ++--
6 files changed, 8 insertions(+), 8 deletions(-)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_internal.c b/drivers/gpu/drm/i915/gem/i915_gem_internal.c
index a9d65fc8aa0e..4b7afa0fc85d 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_internal.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_internal.c
@@ -42,7 +42,7 @@ static int i915_gem_object_get_pages_internal(struct drm_i915_gem_object *obj)
max_order = MAX_ORDER;
#ifdef CONFIG_SWIOTLB
- if (is_swiotlb_active()) {
+ if (is_swiotlb_active(obj->base.dev->dev)) {
unsigned int max_segment;
max_segment = swiotlb_max_segment();
diff --git a/drivers/gpu/drm/nouveau/nouveau_ttm.c b/drivers/gpu/drm/nouveau/nouveau_ttm.c
index 9662522aa066..be15bfd9e0ee 100644
--- a/drivers/gpu/drm/nouveau/nouveau_ttm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_ttm.c
@@ -321,7 +321,7 @@ nouveau_ttm_init(struct nouveau_drm *drm)
}
#if IS_ENABLED(CONFIG_SWIOTLB) && IS_ENABLED(CONFIG_X86)
- need_swiotlb = is_swiotlb_active();
+ need_swiotlb = is_swiotlb_active(dev->dev);
#endif
ret = ttm_bo_device_init(&drm->ttm.bdev, &nouveau_bo_driver,
diff --git a/drivers/pci/xen-pcifront.c b/drivers/pci/xen-pcifront.c
index b7a8f3a1921f..0d56985bfe81 100644
--- a/drivers/pci/xen-pcifront.c
+++ b/drivers/pci/xen-pcifront.c
@@ -693,7 +693,7 @@ static int pcifront_connect_and_init_dma(struct pcifront_device *pdev)
spin_unlock(&pcifront_dev_lock);
- if (!err && !is_swiotlb_active()) {
+ if (!err && !is_swiotlb_active(&pdev->xdev->dev)) {
err = pci_xen_swiotlb_init_late();
if (err)
dev_err(&pdev->xdev->dev, "Could not setup SWIOTLB!\n");
diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index d1f3d95881cd..dd1c30a83058 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -112,7 +112,7 @@ static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr)
void __init swiotlb_exit(void);
unsigned int swiotlb_max_segment(void);
size_t swiotlb_max_mapping_size(struct device *dev);
-bool is_swiotlb_active(void);
+bool is_swiotlb_active(struct device *dev);
void __init swiotlb_adjust_size(unsigned long size);
#else
#define swiotlb_force SWIOTLB_NO_FORCE
@@ -132,7 +132,7 @@ static inline size_t swiotlb_max_mapping_size(struct device *dev)
return SIZE_MAX;
}
-static inline bool is_swiotlb_active(void)
+static inline bool is_swiotlb_active(struct device *dev)
{
return false;
}
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 84c9feb5474a..7a88c34d0867 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -495,7 +495,7 @@ int dma_direct_supported(struct device *dev, u64 mask)
size_t dma_direct_max_mapping_size(struct device *dev)
{
/* If SWIOTLB is active, use its maximum mapping size */
- if (is_swiotlb_active() &&
+ if (is_swiotlb_active(dev) &&
(dma_addressing_limited(dev) || swiotlb_force == SWIOTLB_FORCE))
return swiotlb_max_mapping_size(dev);
return SIZE_MAX;
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 72a4289faed1..8a120f42340b 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -664,9 +664,9 @@ size_t swiotlb_max_mapping_size(struct device *dev)
return ((size_t)IO_TLB_SIZE) * IO_TLB_SEGSIZE;
}
-bool is_swiotlb_active(void)
+bool is_swiotlb_active(struct device *dev)
{
- return io_tlb_default_mem != NULL;
+ return dev->dma_io_tlb_mem != NULL;
}
EXPORT_SYMBOL_GPL(is_swiotlb_active);
--
2.32.0.288.g62a8d224e6-goog
^ permalink raw reply related [flat|nested] 44+ messages in thread
* [PATCH v15 06/12] swiotlb: Use is_swiotlb_force_bounce for swiotlb data bouncing
2021-06-24 15:55 [PATCH v15 00/12] Restricted DMA Claire Chang
` (4 preceding siblings ...)
2021-06-24 15:55 ` [PATCH v15 05/12] swiotlb: Update is_swiotlb_active " Claire Chang
@ 2021-06-24 15:55 ` Claire Chang
[not found] ` <YNvMDFWKXSm4LRfZ@Ryzen-9-3900X.localdomain>
2021-06-24 15:55 ` [PATCH v15 07/12] swiotlb: Move alloc_size to swiotlb_find_slots Claire Chang
` (6 subsequent siblings)
12 siblings, 1 reply; 44+ messages in thread
From: Claire Chang @ 2021-06-24 15:55 UTC (permalink / raw)
To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross,
Christoph Hellwig, Marek Szyprowski
Cc: benh, paulus, list@263.net:IOMMU DRIVERS, sstabellini,
Robin Murphy, grant.likely, xypron.glpk, Thierry Reding, mingo,
bauerman, peterz, Greg KH, Saravana Kannan, Rafael J . Wysocki,
heikki.krogerus, Andy Shevchenko, Randy Dunlap, Dan Williams,
Bartosz Golaszewski, linux-devicetree, lkml, linuxppc-dev,
xen-devel, Nicolas Boichat, Jim Quinlan, tfiga, bskeggs,
bhelgaas, chris, tientzu, daniel, airlied, dri-devel, intel-gfx,
jani.nikula, jxgao, joonas.lahtinen, linux-pci,
maarten.lankhorst, matthew.auld, rodrigo.vivi, thomas.hellstrom,
thomas.lendacky, quic_qiancai
Propagate the swiotlb_force into io_tlb_default_mem->force_bounce and
use it to determine whether to bounce the data or not. This will be
useful later to allow for different pools.
Signed-off-by: Claire Chang <tientzu@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Stefano Stabellini <sstabellini@kernel.org>
Tested-by: Will Deacon <will@kernel.org>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
---
drivers/xen/swiotlb-xen.c | 2 +-
include/linux/swiotlb.h | 13 +++++++++++++
kernel/dma/direct.c | 2 +-
kernel/dma/direct.h | 2 +-
kernel/dma/swiotlb.c | 4 ++++
5 files changed, 20 insertions(+), 3 deletions(-)
diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c
index 0c6ed09f8513..4730a146fa35 100644
--- a/drivers/xen/swiotlb-xen.c
+++ b/drivers/xen/swiotlb-xen.c
@@ -369,7 +369,7 @@ static dma_addr_t xen_swiotlb_map_page(struct device *dev, struct page *page,
if (dma_capable(dev, dev_addr, size, true) &&
!range_straddles_page_boundary(phys, size) &&
!xen_arch_need_swiotlb(dev, phys, dev_addr) &&
- swiotlb_force != SWIOTLB_FORCE)
+ !is_swiotlb_force_bounce(dev))
goto done;
/*
diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index dd1c30a83058..da348671b0d5 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -84,6 +84,7 @@ extern enum swiotlb_force swiotlb_force;
* unmap calls.
* @debugfs: The dentry to debugfs.
* @late_alloc: %true if allocated using the page allocator
+ * @force_bounce: %true if swiotlb bouncing is forced
*/
struct io_tlb_mem {
phys_addr_t start;
@@ -94,6 +95,7 @@ struct io_tlb_mem {
spinlock_t lock;
struct dentry *debugfs;
bool late_alloc;
+ bool force_bounce;
struct io_tlb_slot {
phys_addr_t orig_addr;
size_t alloc_size;
@@ -109,6 +111,13 @@ static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr)
return mem && paddr >= mem->start && paddr < mem->end;
}
+static inline bool is_swiotlb_force_bounce(struct device *dev)
+{
+ struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
+
+ return mem && mem->force_bounce;
+}
+
void __init swiotlb_exit(void);
unsigned int swiotlb_max_segment(void);
size_t swiotlb_max_mapping_size(struct device *dev);
@@ -120,6 +129,10 @@ static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr)
{
return false;
}
+static inline bool is_swiotlb_force_bounce(struct device *dev)
+{
+ return false;
+}
static inline void swiotlb_exit(void)
{
}
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 7a88c34d0867..a92465b4eb12 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -496,7 +496,7 @@ size_t dma_direct_max_mapping_size(struct device *dev)
{
/* If SWIOTLB is active, use its maximum mapping size */
if (is_swiotlb_active(dev) &&
- (dma_addressing_limited(dev) || swiotlb_force == SWIOTLB_FORCE))
+ (dma_addressing_limited(dev) || is_swiotlb_force_bounce(dev)))
return swiotlb_max_mapping_size(dev);
return SIZE_MAX;
}
diff --git a/kernel/dma/direct.h b/kernel/dma/direct.h
index 13e9e7158d94..4632b0f4f72e 100644
--- a/kernel/dma/direct.h
+++ b/kernel/dma/direct.h
@@ -87,7 +87,7 @@ static inline dma_addr_t dma_direct_map_page(struct device *dev,
phys_addr_t phys = page_to_phys(page) + offset;
dma_addr_t dma_addr = phys_to_dma(dev, phys);
- if (unlikely(swiotlb_force == SWIOTLB_FORCE))
+ if (is_swiotlb_force_bounce(dev))
return swiotlb_map(dev, phys, size, dir, attrs);
if (unlikely(!dma_capable(dev, dma_addr, size, true))) {
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 8a120f42340b..0d294bbf274c 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -179,6 +179,10 @@ static void swiotlb_init_io_tlb_mem(struct io_tlb_mem *mem, phys_addr_t start,
mem->end = mem->start + bytes;
mem->index = 0;
mem->late_alloc = late_alloc;
+
+ if (swiotlb_force == SWIOTLB_FORCE)
+ mem->force_bounce = true;
+
spin_lock_init(&mem->lock);
for (i = 0; i < mem->nslabs; i++) {
mem->slots[i].list = IO_TLB_SEGSIZE - io_tlb_offset(i);
--
2.32.0.288.g62a8d224e6-goog
^ permalink raw reply related [flat|nested] 44+ messages in thread
* [PATCH v15 07/12] swiotlb: Move alloc_size to swiotlb_find_slots
2021-06-24 15:55 [PATCH v15 00/12] Restricted DMA Claire Chang
` (5 preceding siblings ...)
2021-06-24 15:55 ` [PATCH v15 06/12] swiotlb: Use is_swiotlb_force_bounce for swiotlb data bouncing Claire Chang
@ 2021-06-24 15:55 ` Claire Chang
2021-06-24 15:55 ` [PATCH v15 08/12] swiotlb: Refactor swiotlb_tbl_unmap_single Claire Chang
` (5 subsequent siblings)
12 siblings, 0 replies; 44+ messages in thread
From: Claire Chang @ 2021-06-24 15:55 UTC (permalink / raw)
To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross,
Christoph Hellwig, Marek Szyprowski
Cc: benh, paulus, list@263.net:IOMMU DRIVERS, sstabellini,
Robin Murphy, grant.likely, xypron.glpk, Thierry Reding, mingo,
bauerman, peterz, Greg KH, Saravana Kannan, Rafael J . Wysocki,
heikki.krogerus, Andy Shevchenko, Randy Dunlap, Dan Williams,
Bartosz Golaszewski, linux-devicetree, lkml, linuxppc-dev,
xen-devel, Nicolas Boichat, Jim Quinlan, tfiga, bskeggs,
bhelgaas, chris, tientzu, daniel, airlied, dri-devel, intel-gfx,
jani.nikula, jxgao, joonas.lahtinen, linux-pci,
maarten.lankhorst, matthew.auld, rodrigo.vivi, thomas.hellstrom,
thomas.lendacky, quic_qiancai
Rename find_slots to swiotlb_find_slots and move the maintenance of
alloc_size to it for better code reusability later.
Signed-off-by: Claire Chang <tientzu@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Stefano Stabellini <sstabellini@kernel.org>
Tested-by: Will Deacon <will@kernel.org>
---
kernel/dma/swiotlb.c | 17 +++++++++--------
1 file changed, 9 insertions(+), 8 deletions(-)
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 0d294bbf274c..b41d16e92cf6 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -432,8 +432,8 @@ static unsigned int wrap_index(struct io_tlb_mem *mem, unsigned int index)
* Find a suitable number of IO TLB entries size that will fit this request and
* allocate a buffer from that IO TLB pool.
*/
-static int find_slots(struct device *dev, phys_addr_t orig_addr,
- size_t alloc_size)
+static int swiotlb_find_slots(struct device *dev, phys_addr_t orig_addr,
+ size_t alloc_size)
{
struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
unsigned long boundary_mask = dma_get_seg_boundary(dev);
@@ -444,6 +444,7 @@ static int find_slots(struct device *dev, phys_addr_t orig_addr,
dma_get_min_align_mask(dev) & ~(IO_TLB_SIZE - 1);
unsigned int nslots = nr_slots(alloc_size), stride;
unsigned int index, wrap, count = 0, i;
+ unsigned int offset = swiotlb_align_offset(dev, orig_addr);
unsigned long flags;
BUG_ON(!nslots);
@@ -488,8 +489,11 @@ static int find_slots(struct device *dev, phys_addr_t orig_addr,
return -1;
found:
- for (i = index; i < index + nslots; i++)
+ for (i = index; i < index + nslots; i++) {
mem->slots[i].list = 0;
+ mem->slots[i].alloc_size =
+ alloc_size - (offset + ((i - index) << IO_TLB_SHIFT));
+ }
for (i = index - 1;
io_tlb_offset(i) != IO_TLB_SEGSIZE - 1 &&
mem->slots[i].list; i--)
@@ -530,7 +534,7 @@ phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr,
return (phys_addr_t)DMA_MAPPING_ERROR;
}
- index = find_slots(dev, orig_addr, alloc_size + offset);
+ index = swiotlb_find_slots(dev, orig_addr, alloc_size + offset);
if (index == -1) {
if (!(attrs & DMA_ATTR_NO_WARN))
dev_warn_ratelimited(dev,
@@ -544,11 +548,8 @@ phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr,
* This is needed when we sync the memory. Then we sync the buffer if
* needed.
*/
- for (i = 0; i < nr_slots(alloc_size + offset); i++) {
+ for (i = 0; i < nr_slots(alloc_size + offset); i++)
mem->slots[index + i].orig_addr = slot_addr(orig_addr, i);
- mem->slots[index + i].alloc_size =
- alloc_size - (i << IO_TLB_SHIFT);
- }
tlb_addr = slot_addr(mem->start, index) + offset;
if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) &&
(dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL))
--
2.32.0.288.g62a8d224e6-goog
^ permalink raw reply related [flat|nested] 44+ messages in thread
* [PATCH v15 08/12] swiotlb: Refactor swiotlb_tbl_unmap_single
2021-06-24 15:55 [PATCH v15 00/12] Restricted DMA Claire Chang
` (6 preceding siblings ...)
2021-06-24 15:55 ` [PATCH v15 07/12] swiotlb: Move alloc_size to swiotlb_find_slots Claire Chang
@ 2021-06-24 15:55 ` Claire Chang
2021-06-24 15:55 ` [PATCH v15 09/12] swiotlb: Add restricted DMA alloc/free support Claire Chang
` (4 subsequent siblings)
12 siblings, 0 replies; 44+ messages in thread
From: Claire Chang @ 2021-06-24 15:55 UTC (permalink / raw)
To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross,
Christoph Hellwig, Marek Szyprowski
Cc: benh, paulus, list@263.net:IOMMU DRIVERS, sstabellini,
Robin Murphy, grant.likely, xypron.glpk, Thierry Reding, mingo,
bauerman, peterz, Greg KH, Saravana Kannan, Rafael J . Wysocki,
heikki.krogerus, Andy Shevchenko, Randy Dunlap, Dan Williams,
Bartosz Golaszewski, linux-devicetree, lkml, linuxppc-dev,
xen-devel, Nicolas Boichat, Jim Quinlan, tfiga, bskeggs,
bhelgaas, chris, tientzu, daniel, airlied, dri-devel, intel-gfx,
jani.nikula, jxgao, joonas.lahtinen, linux-pci,
maarten.lankhorst, matthew.auld, rodrigo.vivi, thomas.hellstrom,
thomas.lendacky, quic_qiancai
Add a new function, swiotlb_release_slots, to make the code reusable for
supporting different bounce buffer pools.
Signed-off-by: Claire Chang <tientzu@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Stefano Stabellini <sstabellini@kernel.org>
Tested-by: Will Deacon <will@kernel.org>
---
kernel/dma/swiotlb.c | 35 ++++++++++++++++++++---------------
1 file changed, 20 insertions(+), 15 deletions(-)
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index b41d16e92cf6..93752e752e76 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -557,27 +557,15 @@ phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr,
return tlb_addr;
}
-/*
- * tlb_addr is the physical address of the bounce buffer to unmap.
- */
-void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr,
- size_t mapping_size, enum dma_data_direction dir,
- unsigned long attrs)
+static void swiotlb_release_slots(struct device *dev, phys_addr_t tlb_addr)
{
- struct io_tlb_mem *mem = hwdev->dma_io_tlb_mem;
+ struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
unsigned long flags;
- unsigned int offset = swiotlb_align_offset(hwdev, tlb_addr);
+ unsigned int offset = swiotlb_align_offset(dev, tlb_addr);
int index = (tlb_addr - offset - mem->start) >> IO_TLB_SHIFT;
int nslots = nr_slots(mem->slots[index].alloc_size + offset);
int count, i;
- /*
- * First, sync the memory before unmapping the entry
- */
- if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) &&
- (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL))
- swiotlb_bounce(hwdev, tlb_addr, mapping_size, DMA_FROM_DEVICE);
-
/*
* Return the buffer to the free list by setting the corresponding
* entries to indicate the number of contiguous entries available.
@@ -612,6 +600,23 @@ void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr,
spin_unlock_irqrestore(&mem->lock, flags);
}
+/*
+ * tlb_addr is the physical address of the bounce buffer to unmap.
+ */
+void swiotlb_tbl_unmap_single(struct device *dev, phys_addr_t tlb_addr,
+ size_t mapping_size, enum dma_data_direction dir,
+ unsigned long attrs)
+{
+ /*
+ * First, sync the memory before unmapping the entry
+ */
+ if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) &&
+ (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL))
+ swiotlb_bounce(dev, tlb_addr, mapping_size, DMA_FROM_DEVICE);
+
+ swiotlb_release_slots(dev, tlb_addr);
+}
+
void swiotlb_sync_single_for_device(struct device *dev, phys_addr_t tlb_addr,
size_t size, enum dma_data_direction dir)
{
--
2.32.0.288.g62a8d224e6-goog
^ permalink raw reply related [flat|nested] 44+ messages in thread
* [PATCH v15 09/12] swiotlb: Add restricted DMA alloc/free support
2021-06-24 15:55 [PATCH v15 00/12] Restricted DMA Claire Chang
` (7 preceding siblings ...)
2021-06-24 15:55 ` [PATCH v15 08/12] swiotlb: Refactor swiotlb_tbl_unmap_single Claire Chang
@ 2021-06-24 15:55 ` Claire Chang
2021-06-24 15:55 ` [PATCH v15 10/12] swiotlb: Add restricted DMA pool initialization Claire Chang
` (3 subsequent siblings)
12 siblings, 0 replies; 44+ messages in thread
From: Claire Chang @ 2021-06-24 15:55 UTC (permalink / raw)
To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross,
Christoph Hellwig, Marek Szyprowski
Cc: benh, paulus, list@263.net:IOMMU DRIVERS, sstabellini,
Robin Murphy, grant.likely, xypron.glpk, Thierry Reding, mingo,
bauerman, peterz, Greg KH, Saravana Kannan, Rafael J . Wysocki,
heikki.krogerus, Andy Shevchenko, Randy Dunlap, Dan Williams,
Bartosz Golaszewski, linux-devicetree, lkml, linuxppc-dev,
xen-devel, Nicolas Boichat, Jim Quinlan, tfiga, bskeggs,
bhelgaas, chris, tientzu, daniel, airlied, dri-devel, intel-gfx,
jani.nikula, jxgao, joonas.lahtinen, linux-pci,
maarten.lankhorst, matthew.auld, rodrigo.vivi, thomas.hellstrom,
thomas.lendacky, quic_qiancai
Add the functions, swiotlb_{alloc,free} and is_swiotlb_for_alloc to
support the memory allocation from restricted DMA pool.
The restricted DMA pool is preferred if available.
Note that since coherent allocation needs remapping, one must set up
another device coherent pool by shared-dma-pool and use
dma_alloc_from_dev_coherent instead for atomic coherent allocation.
Signed-off-by: Claire Chang <tientzu@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Stefano Stabellini <sstabellini@kernel.org>
Tested-by: Will Deacon <will@kernel.org>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
---
include/linux/swiotlb.h | 26 ++++++++++++++++++++++
kernel/dma/direct.c | 49 +++++++++++++++++++++++++++++++----------
kernel/dma/swiotlb.c | 38 ++++++++++++++++++++++++++++++--
3 files changed, 99 insertions(+), 14 deletions(-)
diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index da348671b0d5..3b9454d1e498 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -85,6 +85,7 @@ extern enum swiotlb_force swiotlb_force;
* @debugfs: The dentry to debugfs.
* @late_alloc: %true if allocated using the page allocator
* @force_bounce: %true if swiotlb bouncing is forced
+ * @for_alloc: %true if the pool is used for memory allocation
*/
struct io_tlb_mem {
phys_addr_t start;
@@ -96,6 +97,7 @@ struct io_tlb_mem {
struct dentry *debugfs;
bool late_alloc;
bool force_bounce;
+ bool for_alloc;
struct io_tlb_slot {
phys_addr_t orig_addr;
size_t alloc_size;
@@ -158,4 +160,28 @@ static inline void swiotlb_adjust_size(unsigned long size)
extern void swiotlb_print_info(void);
extern void swiotlb_set_max_segment(unsigned int);
+#ifdef CONFIG_DMA_RESTRICTED_POOL
+struct page *swiotlb_alloc(struct device *dev, size_t size);
+bool swiotlb_free(struct device *dev, struct page *page, size_t size);
+
+static inline bool is_swiotlb_for_alloc(struct device *dev)
+{
+ return dev->dma_io_tlb_mem->for_alloc;
+}
+#else
+static inline struct page *swiotlb_alloc(struct device *dev, size_t size)
+{
+ return NULL;
+}
+static inline bool swiotlb_free(struct device *dev, struct page *page,
+ size_t size)
+{
+ return false;
+}
+static inline bool is_swiotlb_for_alloc(struct device *dev)
+{
+ return false;
+}
+#endif /* CONFIG_DMA_RESTRICTED_POOL */
+
#endif /* __LINUX_SWIOTLB_H */
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index a92465b4eb12..2de33e5d302b 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -75,6 +75,15 @@ static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size)
min_not_zero(dev->coherent_dma_mask, dev->bus_dma_limit);
}
+static void __dma_direct_free_pages(struct device *dev, struct page *page,
+ size_t size)
+{
+ if (IS_ENABLED(CONFIG_DMA_RESTRICTED_POOL) &&
+ swiotlb_free(dev, page, size))
+ return;
+ dma_free_contiguous(dev, page, size);
+}
+
static struct page *__dma_direct_alloc_pages(struct device *dev, size_t size,
gfp_t gfp)
{
@@ -86,6 +95,16 @@ static struct page *__dma_direct_alloc_pages(struct device *dev, size_t size,
gfp |= dma_direct_optimal_gfp_mask(dev, dev->coherent_dma_mask,
&phys_limit);
+ if (IS_ENABLED(CONFIG_DMA_RESTRICTED_POOL) &&
+ is_swiotlb_for_alloc(dev)) {
+ page = swiotlb_alloc(dev, size);
+ if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {
+ __dma_direct_free_pages(dev, page, size);
+ return NULL;
+ }
+ return page;
+ }
+
page = dma_alloc_contiguous(dev, size, gfp);
if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {
dma_free_contiguous(dev, page, size);
@@ -142,7 +161,7 @@ void *dma_direct_alloc(struct device *dev, size_t size,
gfp |= __GFP_NOWARN;
if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) &&
- !force_dma_unencrypted(dev)) {
+ !force_dma_unencrypted(dev) && !is_swiotlb_for_alloc(dev)) {
page = __dma_direct_alloc_pages(dev, size, gfp & ~__GFP_ZERO);
if (!page)
return NULL;
@@ -155,18 +174,23 @@ void *dma_direct_alloc(struct device *dev, size_t size,
}
if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) &&
- !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
- !dev_is_dma_coherent(dev))
+ !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && !dev_is_dma_coherent(dev) &&
+ !is_swiotlb_for_alloc(dev))
return arch_dma_alloc(dev, size, dma_handle, gfp, attrs);
/*
* Remapping or decrypting memory may block. If either is required and
* we can't block, allocate the memory from the atomic pools.
+ * If restricted DMA (i.e., is_swiotlb_for_alloc) is required, one must
+ * set up another device coherent pool by shared-dma-pool and use
+ * dma_alloc_from_dev_coherent instead.
*/
if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) &&
!gfpflags_allow_blocking(gfp) &&
(force_dma_unencrypted(dev) ||
- (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && !dev_is_dma_coherent(dev))))
+ (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
+ !dev_is_dma_coherent(dev))) &&
+ !is_swiotlb_for_alloc(dev))
return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp);
/* we always manually zero the memory once we are done */
@@ -237,7 +261,7 @@ void *dma_direct_alloc(struct device *dev, size_t size,
return NULL;
}
out_free_pages:
- dma_free_contiguous(dev, page, size);
+ __dma_direct_free_pages(dev, page, size);
return NULL;
}
@@ -247,15 +271,15 @@ void dma_direct_free(struct device *dev, size_t size,
unsigned int page_order = get_order(size);
if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) &&
- !force_dma_unencrypted(dev)) {
+ !force_dma_unencrypted(dev) && !is_swiotlb_for_alloc(dev)) {
/* cpu_addr is a struct page cookie, not a kernel address */
dma_free_contiguous(dev, cpu_addr, size);
return;
}
if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) &&
- !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
- !dev_is_dma_coherent(dev)) {
+ !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && !dev_is_dma_coherent(dev) &&
+ !is_swiotlb_for_alloc(dev)) {
arch_dma_free(dev, size, cpu_addr, dma_addr, attrs);
return;
}
@@ -273,7 +297,7 @@ void dma_direct_free(struct device *dev, size_t size,
else if (IS_ENABLED(CONFIG_ARCH_HAS_DMA_CLEAR_UNCACHED))
arch_dma_clear_uncached(cpu_addr, size);
- dma_free_contiguous(dev, dma_direct_to_page(dev, dma_addr), size);
+ __dma_direct_free_pages(dev, dma_direct_to_page(dev, dma_addr), size);
}
struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
@@ -283,7 +307,8 @@ struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
void *ret;
if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) &&
- force_dma_unencrypted(dev) && !gfpflags_allow_blocking(gfp))
+ force_dma_unencrypted(dev) && !gfpflags_allow_blocking(gfp) &&
+ !is_swiotlb_for_alloc(dev))
return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp);
page = __dma_direct_alloc_pages(dev, size, gfp);
@@ -310,7 +335,7 @@ struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
*dma_handle = phys_to_dma_direct(dev, page_to_phys(page));
return page;
out_free_pages:
- dma_free_contiguous(dev, page, size);
+ __dma_direct_free_pages(dev, page, size);
return NULL;
}
@@ -329,7 +354,7 @@ void dma_direct_free_pages(struct device *dev, size_t size,
if (force_dma_unencrypted(dev))
set_memory_encrypted((unsigned long)vaddr, 1 << page_order);
- dma_free_contiguous(dev, page, size);
+ __dma_direct_free_pages(dev, page, size);
}
#if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 93752e752e76..6a7c6e30eb4b 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -464,8 +464,9 @@ static int swiotlb_find_slots(struct device *dev, phys_addr_t orig_addr,
index = wrap = wrap_index(mem, ALIGN(mem->index, stride));
do {
- if ((slot_addr(tbl_dma_addr, index) & iotlb_align_mask) !=
- (orig_addr & iotlb_align_mask)) {
+ if (orig_addr &&
+ (slot_addr(tbl_dma_addr, index) & iotlb_align_mask) !=
+ (orig_addr & iotlb_align_mask)) {
index = wrap_index(mem, index + 1);
continue;
}
@@ -704,3 +705,36 @@ static int __init swiotlb_create_default_debugfs(void)
late_initcall(swiotlb_create_default_debugfs);
#endif
+
+#ifdef CONFIG_DMA_RESTRICTED_POOL
+struct page *swiotlb_alloc(struct device *dev, size_t size)
+{
+ struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
+ phys_addr_t tlb_addr;
+ int index;
+
+ if (!mem)
+ return NULL;
+
+ index = swiotlb_find_slots(dev, 0, size);
+ if (index == -1)
+ return NULL;
+
+ tlb_addr = slot_addr(mem->start, index);
+
+ return pfn_to_page(PFN_DOWN(tlb_addr));
+}
+
+bool swiotlb_free(struct device *dev, struct page *page, size_t size)
+{
+ phys_addr_t tlb_addr = page_to_phys(page);
+
+ if (!is_swiotlb_buffer(dev, tlb_addr))
+ return false;
+
+ swiotlb_release_slots(dev, tlb_addr);
+
+ return true;
+}
+
+#endif /* CONFIG_DMA_RESTRICTED_POOL */
--
2.32.0.288.g62a8d224e6-goog
^ permalink raw reply related [flat|nested] 44+ messages in thread
* [PATCH v15 10/12] swiotlb: Add restricted DMA pool initialization
2021-06-24 15:55 [PATCH v15 00/12] Restricted DMA Claire Chang
` (8 preceding siblings ...)
2021-06-24 15:55 ` [PATCH v15 09/12] swiotlb: Add restricted DMA alloc/free support Claire Chang
@ 2021-06-24 15:55 ` Claire Chang
2021-08-24 14:26 ` Guenter Roeck
2021-08-27 6:58 ` Andy Shevchenko
2021-06-24 15:55 ` [PATCH v15 11/12] dt-bindings: of: Add restricted DMA pool Claire Chang
` (2 subsequent siblings)
12 siblings, 2 replies; 44+ messages in thread
From: Claire Chang @ 2021-06-24 15:55 UTC (permalink / raw)
To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross,
Christoph Hellwig, Marek Szyprowski
Cc: benh, paulus, list@263.net:IOMMU DRIVERS, sstabellini,
Robin Murphy, grant.likely, xypron.glpk, Thierry Reding, mingo,
bauerman, peterz, Greg KH, Saravana Kannan, Rafael J . Wysocki,
heikki.krogerus, Andy Shevchenko, Randy Dunlap, Dan Williams,
Bartosz Golaszewski, linux-devicetree, lkml, linuxppc-dev,
xen-devel, Nicolas Boichat, Jim Quinlan, tfiga, bskeggs,
bhelgaas, chris, tientzu, daniel, airlied, dri-devel, intel-gfx,
jani.nikula, jxgao, joonas.lahtinen, linux-pci,
maarten.lankhorst, matthew.auld, rodrigo.vivi, thomas.hellstrom,
thomas.lendacky, quic_qiancai
Add the initialization function to create restricted DMA pools from
matching reserved-memory nodes.
Regardless of swiotlb setting, the restricted DMA pool is preferred if
available.
The restricted DMA pools provide a basic level of protection against the
DMA overwriting buffer contents at unexpected times. However, to protect
against general data leakage and system memory corruption, the system
needs to provide a way to lock down the memory access, e.g., MPU.
Signed-off-by: Claire Chang <tientzu@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Stefano Stabellini <sstabellini@kernel.org>
Tested-by: Will Deacon <will@kernel.org>
---
include/linux/swiotlb.h | 3 +-
kernel/dma/Kconfig | 14 ++++++++
kernel/dma/swiotlb.c | 76 +++++++++++++++++++++++++++++++++++++++++
3 files changed, 92 insertions(+), 1 deletion(-)
diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index 3b9454d1e498..39284ff2a6cd 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -73,7 +73,8 @@ extern enum swiotlb_force swiotlb_force;
* range check to see if the memory was in fact allocated by this
* API.
* @nslabs: The number of IO TLB blocks (in groups of 64) between @start and
- * @end. This is command line adjustable via setup_io_tlb_npages.
+ * @end. For default swiotlb, this is command line adjustable via
+ * setup_io_tlb_npages.
* @used: The number of used IO TLB block.
* @list: The free list describing the number of free entries available
* from each index.
diff --git a/kernel/dma/Kconfig b/kernel/dma/Kconfig
index 77b405508743..3e961dc39634 100644
--- a/kernel/dma/Kconfig
+++ b/kernel/dma/Kconfig
@@ -80,6 +80,20 @@ config SWIOTLB
bool
select NEED_DMA_MAP_STATE
+config DMA_RESTRICTED_POOL
+ bool "DMA Restricted Pool"
+ depends on OF && OF_RESERVED_MEM
+ select SWIOTLB
+ help
+ This enables support for restricted DMA pools which provide a level of
+ DMA memory protection on systems with limited hardware protection
+ capabilities, such as those lacking an IOMMU.
+
+ For more information see
+ <Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt>
+ and <kernel/dma/swiotlb.c>.
+ If unsure, say "n".
+
#
# Should be selected if we can mmap non-coherent mappings to userspace.
# The only thing that is really required is a way to set an uncached bit
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 6a7c6e30eb4b..3baf49c9b766 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -39,6 +39,13 @@
#ifdef CONFIG_DEBUG_FS
#include <linux/debugfs.h>
#endif
+#ifdef CONFIG_DMA_RESTRICTED_POOL
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <linux/of_reserved_mem.h>
+#include <linux/slab.h>
+#endif
#include <asm/io.h>
#include <asm/dma.h>
@@ -737,4 +744,73 @@ bool swiotlb_free(struct device *dev, struct page *page, size_t size)
return true;
}
+static int rmem_swiotlb_device_init(struct reserved_mem *rmem,
+ struct device *dev)
+{
+ struct io_tlb_mem *mem = rmem->priv;
+ unsigned long nslabs = rmem->size >> IO_TLB_SHIFT;
+
+ /*
+ * Since multiple devices can share the same pool, the private data,
+ * io_tlb_mem struct, will be initialized by the first device attached
+ * to it.
+ */
+ if (!mem) {
+ mem = kzalloc(struct_size(mem, slots, nslabs), GFP_KERNEL);
+ if (!mem)
+ return -ENOMEM;
+
+ set_memory_decrypted((unsigned long)phys_to_virt(rmem->base),
+ rmem->size >> PAGE_SHIFT);
+ swiotlb_init_io_tlb_mem(mem, rmem->base, nslabs, false);
+ mem->force_bounce = true;
+ mem->for_alloc = true;
+
+ rmem->priv = mem;
+
+ if (IS_ENABLED(CONFIG_DEBUG_FS)) {
+ mem->debugfs =
+ debugfs_create_dir(rmem->name, debugfs_dir);
+ swiotlb_create_debugfs_files(mem);
+ }
+ }
+
+ dev->dma_io_tlb_mem = mem;
+
+ return 0;
+}
+
+static void rmem_swiotlb_device_release(struct reserved_mem *rmem,
+ struct device *dev)
+{
+ dev->dma_io_tlb_mem = io_tlb_default_mem;
+}
+
+static const struct reserved_mem_ops rmem_swiotlb_ops = {
+ .device_init = rmem_swiotlb_device_init,
+ .device_release = rmem_swiotlb_device_release,
+};
+
+static int __init rmem_swiotlb_setup(struct reserved_mem *rmem)
+{
+ unsigned long node = rmem->fdt_node;
+
+ if (of_get_flat_dt_prop(node, "reusable", NULL) ||
+ of_get_flat_dt_prop(node, "linux,cma-default", NULL) ||
+ of_get_flat_dt_prop(node, "linux,dma-default", NULL) ||
+ of_get_flat_dt_prop(node, "no-map", NULL))
+ return -EINVAL;
+
+ if (PageHighMem(pfn_to_page(PHYS_PFN(rmem->base)))) {
+ pr_err("Restricted DMA pool must be accessible within the linear mapping.");
+ return -EINVAL;
+ }
+
+ rmem->ops = &rmem_swiotlb_ops;
+ pr_info("Reserved memory: created restricted DMA pool at %pa, size %ld MiB\n",
+ &rmem->base, (unsigned long)rmem->size / SZ_1M);
+ return 0;
+}
+
+RESERVEDMEM_OF_DECLARE(dma, "restricted-dma-pool", rmem_swiotlb_setup);
#endif /* CONFIG_DMA_RESTRICTED_POOL */
--
2.32.0.288.g62a8d224e6-goog
^ permalink raw reply related [flat|nested] 44+ messages in thread
* Re: [PATCH v15 10/12] swiotlb: Add restricted DMA pool initialization
2021-06-24 15:55 ` [PATCH v15 10/12] swiotlb: Add restricted DMA pool initialization Claire Chang
@ 2021-08-24 14:26 ` Guenter Roeck
2021-08-27 3:50 ` Claire Chang
2021-08-27 6:58 ` Andy Shevchenko
1 sibling, 1 reply; 44+ messages in thread
From: Guenter Roeck @ 2021-08-24 14:26 UTC (permalink / raw)
To: Claire Chang
Cc: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross,
Christoph Hellwig, Marek Szyprowski, benh, paulus,
list@263.net:IOMMU DRIVERS, sstabellini, Robin Murphy,
grant.likely, xypron.glpk, Thierry Reding, mingo, bauerman,
peterz, Greg KH, Saravana Kannan, Rafael J . Wysocki,
heikki.krogerus, Andy Shevchenko, Randy Dunlap, Dan Williams,
Bartosz Golaszewski, linux-devicetree, lkml, linuxppc-dev,
xen-devel, Nicolas Boichat, Jim Quinlan, tfiga, bskeggs,
bhelgaas, chris, daniel, airlied, dri-devel, intel-gfx,
jani.nikula, jxgao, joonas.lahtinen, linux-pci,
maarten.lankhorst, matthew.auld, rodrigo.vivi, thomas.hellstrom,
thomas.lendacky, quic_qiancai
Hi Claire,
On Thu, Jun 24, 2021 at 11:55:24PM +0800, Claire Chang wrote:
> Add the initialization function to create restricted DMA pools from
> matching reserved-memory nodes.
>
> Regardless of swiotlb setting, the restricted DMA pool is preferred if
> available.
>
> The restricted DMA pools provide a basic level of protection against the
> DMA overwriting buffer contents at unexpected times. However, to protect
> against general data leakage and system memory corruption, the system
> needs to provide a way to lock down the memory access, e.g., MPU.
>
> Signed-off-by: Claire Chang <tientzu@chromium.org>
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> Tested-by: Stefano Stabellini <sstabellini@kernel.org>
> Tested-by: Will Deacon <will@kernel.org>
> ---
> include/linux/swiotlb.h | 3 +-
> kernel/dma/Kconfig | 14 ++++++++
> kernel/dma/swiotlb.c | 76 +++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 92 insertions(+), 1 deletion(-)
>
> diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
> index 3b9454d1e498..39284ff2a6cd 100644
> --- a/include/linux/swiotlb.h
> +++ b/include/linux/swiotlb.h
> @@ -73,7 +73,8 @@ extern enum swiotlb_force swiotlb_force;
> * range check to see if the memory was in fact allocated by this
> * API.
> * @nslabs: The number of IO TLB blocks (in groups of 64) between @start and
> - * @end. This is command line adjustable via setup_io_tlb_npages.
> + * @end. For default swiotlb, this is command line adjustable via
> + * setup_io_tlb_npages.
> * @used: The number of used IO TLB block.
> * @list: The free list describing the number of free entries available
> * from each index.
> diff --git a/kernel/dma/Kconfig b/kernel/dma/Kconfig
> index 77b405508743..3e961dc39634 100644
> --- a/kernel/dma/Kconfig
> +++ b/kernel/dma/Kconfig
> @@ -80,6 +80,20 @@ config SWIOTLB
> bool
> select NEED_DMA_MAP_STATE
>
> +config DMA_RESTRICTED_POOL
> + bool "DMA Restricted Pool"
> + depends on OF && OF_RESERVED_MEM
> + select SWIOTLB
This makes SWIOTLB user configurable, which in turn results in
mips64-linux-ld: arch/mips/kernel/setup.o: in function `arch_mem_init':
setup.c:(.init.text+0x19c8): undefined reference to `plat_swiotlb_setup'
make[1]: *** [Makefile:1280: vmlinux] Error 1
when building mips:allmodconfig.
Should this possibly be "depends on SWIOTLB" ?
Thanks,
Guenter
^ permalink raw reply [flat|nested] 44+ messages in thread
* Re: [PATCH v15 10/12] swiotlb: Add restricted DMA pool initialization
2021-08-24 14:26 ` Guenter Roeck
@ 2021-08-27 3:50 ` Claire Chang
0 siblings, 0 replies; 44+ messages in thread
From: Claire Chang @ 2021-08-27 3:50 UTC (permalink / raw)
To: Guenter Roeck
Cc: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross,
Christoph Hellwig, Marek Szyprowski, benh, paulus,
list@263.net:IOMMU DRIVERS, Stefano Stabellini, Robin Murphy,
grant.likely, xypron.glpk, Thierry Reding, mingo, bauerman,
peterz, Greg KH, Saravana Kannan, Rafael J . Wysocki,
heikki.krogerus, Andy Shevchenko, Randy Dunlap, Dan Williams,
Bartosz Golaszewski, linux-devicetree, lkml, linuxppc-dev,
xen-devel, Nicolas Boichat, Jim Quinlan, Tomasz Figa, bskeggs,
Bjorn Helgaas, chris, Daniel Vetter, airlied, dri-devel,
intel-gfx, jani.nikula, Jianxiong Gao, joonas.lahtinen,
linux-pci, maarten.lankhorst, matthew.auld, rodrigo.vivi,
thomas.hellstrom, Tom Lendacky, Qian Cai
On Tue, Aug 24, 2021 at 10:26 PM Guenter Roeck <linux@roeck-us.net> wrote:
>
> Hi Claire,
>
> On Thu, Jun 24, 2021 at 11:55:24PM +0800, Claire Chang wrote:
> > Add the initialization function to create restricted DMA pools from
> > matching reserved-memory nodes.
> >
> > Regardless of swiotlb setting, the restricted DMA pool is preferred if
> > available.
> >
> > The restricted DMA pools provide a basic level of protection against the
> > DMA overwriting buffer contents at unexpected times. However, to protect
> > against general data leakage and system memory corruption, the system
> > needs to provide a way to lock down the memory access, e.g., MPU.
> >
> > Signed-off-by: Claire Chang <tientzu@chromium.org>
> > Reviewed-by: Christoph Hellwig <hch@lst.de>
> > Tested-by: Stefano Stabellini <sstabellini@kernel.org>
> > Tested-by: Will Deacon <will@kernel.org>
> > ---
> > include/linux/swiotlb.h | 3 +-
> > kernel/dma/Kconfig | 14 ++++++++
> > kernel/dma/swiotlb.c | 76 +++++++++++++++++++++++++++++++++++++++++
> > 3 files changed, 92 insertions(+), 1 deletion(-)
> >
> > diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
> > index 3b9454d1e498..39284ff2a6cd 100644
> > --- a/include/linux/swiotlb.h
> > +++ b/include/linux/swiotlb.h
> > @@ -73,7 +73,8 @@ extern enum swiotlb_force swiotlb_force;
> > * range check to see if the memory was in fact allocated by this
> > * API.
> > * @nslabs: The number of IO TLB blocks (in groups of 64) between @start and
> > - * @end. This is command line adjustable via setup_io_tlb_npages.
> > + * @end. For default swiotlb, this is command line adjustable via
> > + * setup_io_tlb_npages.
> > * @used: The number of used IO TLB block.
> > * @list: The free list describing the number of free entries available
> > * from each index.
> > diff --git a/kernel/dma/Kconfig b/kernel/dma/Kconfig
> > index 77b405508743..3e961dc39634 100644
> > --- a/kernel/dma/Kconfig
> > +++ b/kernel/dma/Kconfig
> > @@ -80,6 +80,20 @@ config SWIOTLB
> > bool
> > select NEED_DMA_MAP_STATE
> >
> > +config DMA_RESTRICTED_POOL
> > + bool "DMA Restricted Pool"
> > + depends on OF && OF_RESERVED_MEM
> > + select SWIOTLB
>
> This makes SWIOTLB user configurable, which in turn results in
>
> mips64-linux-ld: arch/mips/kernel/setup.o: in function `arch_mem_init':
> setup.c:(.init.text+0x19c8): undefined reference to `plat_swiotlb_setup'
> make[1]: *** [Makefile:1280: vmlinux] Error 1
>
> when building mips:allmodconfig.
>
> Should this possibly be "depends on SWIOTLB" ?
Patch is sent here: https://lkml.org/lkml/2021/8/26/932
>
> Thanks,
> Guenter
Thanks,
Claire
^ permalink raw reply [flat|nested] 44+ messages in thread
* Re: [PATCH v15 10/12] swiotlb: Add restricted DMA pool initialization
2021-06-24 15:55 ` [PATCH v15 10/12] swiotlb: Add restricted DMA pool initialization Claire Chang
2021-08-24 14:26 ` Guenter Roeck
@ 2021-08-27 6:58 ` Andy Shevchenko
1 sibling, 0 replies; 44+ messages in thread
From: Andy Shevchenko @ 2021-08-27 6:58 UTC (permalink / raw)
To: Claire Chang
Cc: Rob Herring, Michael Ellerman, Joerg Roedel, Will Deacon,
Frank Rowand, Konrad Rzeszutek Wilk, Boris Ostrovsky,
Juergen Gross, Christoph Hellwig, Marek Szyprowski, benh, paulus,
list@263.net:IOMMU DRIVERS, sstabellini, Robin Murphy,
grant.likely, xypron.glpk, Thierry Reding, mingo, bauerman,
peterz, Greg KH, Saravana Kannan, Rafael J . Wysocki,
heikki.krogerus, Andy Shevchenko, Randy Dunlap, Dan Williams,
Bartosz Golaszewski, linux-devicetree, lkml, linuxppc-dev,
xen-devel, Nicolas Boichat, Jim Quinlan, tfiga, bskeggs,
bhelgaas, chris, daniel, airlied, dri-devel, intel-gfx,
jani.nikula, jxgao, joonas.lahtinen, linux-pci,
maarten.lankhorst, matthew.auld, rodrigo.vivi, thomas.hellstrom,
thomas.lendacky, quic_qiancai
On Thu, Jun 24, 2021 at 6:59 PM Claire Chang <tientzu@chromium.org> wrote:
>
> Add the initialization function to create restricted DMA pools from
> matching reserved-memory nodes.
>
> Regardless of swiotlb setting, the restricted DMA pool is preferred if
> available.
>
> The restricted DMA pools provide a basic level of protection against the
> DMA overwriting buffer contents at unexpected times. However, to protect
> against general data leakage and system memory corruption, the system
> needs to provide a way to lock down the memory access, e.g., MPU.
> +static int rmem_swiotlb_device_init(struct reserved_mem *rmem,
> + struct device *dev)
> +{
> + struct io_tlb_mem *mem = rmem->priv;
> + unsigned long nslabs = rmem->size >> IO_TLB_SHIFT;
> +
> + /*
> + * Since multiple devices can share the same pool, the private data,
> + * io_tlb_mem struct, will be initialized by the first device attached
> + * to it.
> + */
> + if (!mem) {
Can it be rather
if (mem)
goto out_assign;
or so?
> + mem = kzalloc(struct_size(mem, slots, nslabs), GFP_KERNEL);
> + if (!mem)
> + return -ENOMEM;
> +
> + set_memory_decrypted((unsigned long)phys_to_virt(rmem->base),
> + rmem->size >> PAGE_SHIFT);
Below you are using a macro from pfn.h, but not here, I think it's PFN_DOWN().
> + swiotlb_init_io_tlb_mem(mem, rmem->base, nslabs, false);
> + mem->force_bounce = true;
> + mem->for_alloc = true;
> +
> + rmem->priv = mem;
> +
> + if (IS_ENABLED(CONFIG_DEBUG_FS)) {
> + mem->debugfs =
> + debugfs_create_dir(rmem->name, debugfs_dir);
> + swiotlb_create_debugfs_files(mem);
> + }
> + }
> +
> + dev->dma_io_tlb_mem = mem;
> +
> + return 0;
> +}
> +
> +static void rmem_swiotlb_device_release(struct reserved_mem *rmem,
> + struct device *dev)
> +{
> + dev->dma_io_tlb_mem = io_tlb_default_mem;
> +}
> +
> +static const struct reserved_mem_ops rmem_swiotlb_ops = {
> + .device_init = rmem_swiotlb_device_init,
> + .device_release = rmem_swiotlb_device_release,
> +};
> +
> +static int __init rmem_swiotlb_setup(struct reserved_mem *rmem)
> +{
> + unsigned long node = rmem->fdt_node;
> +
> + if (of_get_flat_dt_prop(node, "reusable", NULL) ||
> + of_get_flat_dt_prop(node, "linux,cma-default", NULL) ||
> + of_get_flat_dt_prop(node, "linux,dma-default", NULL) ||
> + of_get_flat_dt_prop(node, "no-map", NULL))
> + return -EINVAL;
> +
> + if (PageHighMem(pfn_to_page(PHYS_PFN(rmem->base)))) {
> + pr_err("Restricted DMA pool must be accessible within the linear mapping.");
> + return -EINVAL;
> + }
> +
> + rmem->ops = &rmem_swiotlb_ops;
> + pr_info("Reserved memory: created restricted DMA pool at %pa, size %ld MiB\n",
> + &rmem->base, (unsigned long)rmem->size / SZ_1M);
Oh là là, besides explicit casting that I believe can be avoided, %ld
!= unsigned long. Can you check the printk-formats.rst document?
> + return 0;
> +}
> +
> +RESERVEDMEM_OF_DECLARE(dma, "restricted-dma-pool", rmem_swiotlb_setup);
> #endif /* CONFIG_DMA_RESTRICTED_POOL */
--
With Best Regards,
Andy Shevchenko
^ permalink raw reply [flat|nested] 44+ messages in thread
* [PATCH v15 11/12] dt-bindings: of: Add restricted DMA pool
2021-06-24 15:55 [PATCH v15 00/12] Restricted DMA Claire Chang
` (9 preceding siblings ...)
2021-06-24 15:55 ` [PATCH v15 10/12] swiotlb: Add restricted DMA pool initialization Claire Chang
@ 2021-06-24 15:55 ` Claire Chang
2021-06-24 15:55 ` [PATCH v15 12/12] of: Add plumbing for " Claire Chang
2021-06-24 19:19 ` [PATCH v15 00/12] Restricted DMA Konrad Rzeszutek Wilk
12 siblings, 0 replies; 44+ messages in thread
From: Claire Chang @ 2021-06-24 15:55 UTC (permalink / raw)
To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross,
Christoph Hellwig, Marek Szyprowski
Cc: benh, paulus, list@263.net:IOMMU DRIVERS, sstabellini,
Robin Murphy, grant.likely, xypron.glpk, Thierry Reding, mingo,
bauerman, peterz, Greg KH, Saravana Kannan, Rafael J . Wysocki,
heikki.krogerus, Andy Shevchenko, Randy Dunlap, Dan Williams,
Bartosz Golaszewski, linux-devicetree, lkml, linuxppc-dev,
xen-devel, Nicolas Boichat, Jim Quinlan, tfiga, bskeggs,
bhelgaas, chris, tientzu, daniel, airlied, dri-devel, intel-gfx,
jani.nikula, jxgao, joonas.lahtinen, linux-pci,
maarten.lankhorst, matthew.auld, rodrigo.vivi, thomas.hellstrom,
thomas.lendacky, quic_qiancai
Introduce the new compatible string, restricted-dma-pool, for restricted
DMA. One can specify the address and length of the restricted DMA memory
region by restricted-dma-pool in the reserved-memory node.
Signed-off-by: Claire Chang <tientzu@chromium.org>
Tested-by: Stefano Stabellini <sstabellini@kernel.org>
Tested-by: Will Deacon <will@kernel.org>
---
.../reserved-memory/reserved-memory.txt | 36 +++++++++++++++++--
1 file changed, 33 insertions(+), 3 deletions(-)
diff --git a/Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt b/Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt
index e8d3096d922c..39b5f4c5a511 100644
--- a/Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt
+++ b/Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt
@@ -51,6 +51,23 @@ compatible (optional) - standard definition
used as a shared pool of DMA buffers for a set of devices. It can
be used by an operating system to instantiate the necessary pool
management subsystem if necessary.
+ - restricted-dma-pool: This indicates a region of memory meant to be
+ used as a pool of restricted DMA buffers for a set of devices. The
+ memory region would be the only region accessible to those devices.
+ When using this, the no-map and reusable properties must not be set,
+ so the operating system can create a virtual mapping that will be used
+ for synchronization. The main purpose for restricted DMA is to
+ mitigate the lack of DMA access control on systems without an IOMMU,
+ which could result in the DMA accessing the system memory at
+ unexpected times and/or unexpected addresses, possibly leading to data
+ leakage or corruption. The feature on its own provides a basic level
+ of protection against the DMA overwriting buffer contents at
+ unexpected times. However, to protect against general data leakage and
+ system memory corruption, the system needs to provide way to lock down
+ the memory access, e.g., MPU. Note that since coherent allocation
+ needs remapping, one must set up another device coherent pool by
+ shared-dma-pool and use dma_alloc_from_dev_coherent instead for atomic
+ coherent allocation.
- vendor specific string in the form <vendor>,[<device>-]<usage>
no-map (optional) - empty property
- Indicates the operating system must not create a virtual mapping
@@ -85,10 +102,11 @@ memory-region-names (optional) - a list of names, one for each corresponding
Example
-------
-This example defines 3 contiguous regions are defined for Linux kernel:
+This example defines 4 contiguous regions for Linux kernel:
one default of all device drivers (named linux,cma@72000000 and 64MiB in size),
-one dedicated to the framebuffer device (named framebuffer@78000000, 8MiB), and
-one for multimedia processing (named multimedia-memory@77000000, 64MiB).
+one dedicated to the framebuffer device (named framebuffer@78000000, 8MiB),
+one for multimedia processing (named multimedia-memory@77000000, 64MiB), and
+one for restricted dma pool (named restricted_dma_reserved@0x50000000, 64MiB).
/ {
#address-cells = <1>;
@@ -120,6 +138,11 @@ one for multimedia processing (named multimedia-memory@77000000, 64MiB).
compatible = "acme,multimedia-memory";
reg = <0x77000000 0x4000000>;
};
+
+ restricted_dma_reserved: restricted_dma_reserved {
+ compatible = "restricted-dma-pool";
+ reg = <0x50000000 0x4000000>;
+ };
};
/* ... */
@@ -138,4 +161,11 @@ one for multimedia processing (named multimedia-memory@77000000, 64MiB).
memory-region = <&multimedia_reserved>;
/* ... */
};
+
+ pcie_device: pcie_device@0,0 {
+ reg = <0x83010000 0x0 0x00000000 0x0 0x00100000
+ 0x83010000 0x0 0x00100000 0x0 0x00100000>;
+ memory-region = <&restricted_dma_reserved>;
+ /* ... */
+ };
};
--
2.32.0.288.g62a8d224e6-goog
^ permalink raw reply related [flat|nested] 44+ messages in thread
* [PATCH v15 12/12] of: Add plumbing for restricted DMA pool
2021-06-24 15:55 [PATCH v15 00/12] Restricted DMA Claire Chang
` (10 preceding siblings ...)
2021-06-24 15:55 ` [PATCH v15 11/12] dt-bindings: of: Add restricted DMA pool Claire Chang
@ 2021-06-24 15:55 ` Claire Chang
2021-07-02 3:08 ` Guenter Roeck
2021-06-24 19:19 ` [PATCH v15 00/12] Restricted DMA Konrad Rzeszutek Wilk
12 siblings, 1 reply; 44+ messages in thread
From: Claire Chang @ 2021-06-24 15:55 UTC (permalink / raw)
To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross,
Christoph Hellwig, Marek Szyprowski
Cc: benh, paulus, list@263.net:IOMMU DRIVERS, sstabellini,
Robin Murphy, grant.likely, xypron.glpk, Thierry Reding, mingo,
bauerman, peterz, Greg KH, Saravana Kannan, Rafael J . Wysocki,
heikki.krogerus, Andy Shevchenko, Randy Dunlap, Dan Williams,
Bartosz Golaszewski, linux-devicetree, lkml, linuxppc-dev,
xen-devel, Nicolas Boichat, Jim Quinlan, tfiga, bskeggs,
bhelgaas, chris, tientzu, daniel, airlied, dri-devel, intel-gfx,
jani.nikula, jxgao, joonas.lahtinen, linux-pci,
maarten.lankhorst, matthew.auld, rodrigo.vivi, thomas.hellstrom,
thomas.lendacky, quic_qiancai
If a device is not behind an IOMMU, we look up the device node and set
up the restricted DMA when the restricted-dma-pool is presented.
Signed-off-by: Claire Chang <tientzu@chromium.org>
Tested-by: Stefano Stabellini <sstabellini@kernel.org>
Tested-by: Will Deacon <will@kernel.org>
---
drivers/of/address.c | 33 +++++++++++++++++++++++++++++++++
drivers/of/device.c | 3 +++
drivers/of/of_private.h | 6 ++++++
3 files changed, 42 insertions(+)
diff --git a/drivers/of/address.c b/drivers/of/address.c
index 73ddf2540f3f..cdf700fba5c4 100644
--- a/drivers/of/address.c
+++ b/drivers/of/address.c
@@ -8,6 +8,7 @@
#include <linux/logic_pio.h>
#include <linux/module.h>
#include <linux/of_address.h>
+#include <linux/of_reserved_mem.h>
#include <linux/pci.h>
#include <linux/pci_regs.h>
#include <linux/sizes.h>
@@ -1022,6 +1023,38 @@ int of_dma_get_range(struct device_node *np, const struct bus_dma_region **map)
of_node_put(node);
return ret;
}
+
+int of_dma_set_restricted_buffer(struct device *dev, struct device_node *np)
+{
+ struct device_node *node, *of_node = dev->of_node;
+ int count, i;
+
+ count = of_property_count_elems_of_size(of_node, "memory-region",
+ sizeof(u32));
+ /*
+ * If dev->of_node doesn't exist or doesn't contain memory-region, try
+ * the OF node having DMA configuration.
+ */
+ if (count <= 0) {
+ of_node = np;
+ count = of_property_count_elems_of_size(
+ of_node, "memory-region", sizeof(u32));
+ }
+
+ for (i = 0; i < count; i++) {
+ node = of_parse_phandle(of_node, "memory-region", i);
+ /*
+ * There might be multiple memory regions, but only one
+ * restricted-dma-pool region is allowed.
+ */
+ if (of_device_is_compatible(node, "restricted-dma-pool") &&
+ of_device_is_available(node))
+ return of_reserved_mem_device_init_by_idx(dev, of_node,
+ i);
+ }
+
+ return 0;
+}
#endif /* CONFIG_HAS_DMA */
/**
diff --git a/drivers/of/device.c b/drivers/of/device.c
index 6cb86de404f1..e68316836a7a 100644
--- a/drivers/of/device.c
+++ b/drivers/of/device.c
@@ -165,6 +165,9 @@ int of_dma_configure_id(struct device *dev, struct device_node *np,
arch_setup_dma_ops(dev, dma_start, size, iommu, coherent);
+ if (!iommu)
+ return of_dma_set_restricted_buffer(dev, np);
+
return 0;
}
EXPORT_SYMBOL_GPL(of_dma_configure_id);
diff --git a/drivers/of/of_private.h b/drivers/of/of_private.h
index d9e6a324de0a..25cebbed5f02 100644
--- a/drivers/of/of_private.h
+++ b/drivers/of/of_private.h
@@ -161,12 +161,18 @@ struct bus_dma_region;
#if defined(CONFIG_OF_ADDRESS) && defined(CONFIG_HAS_DMA)
int of_dma_get_range(struct device_node *np,
const struct bus_dma_region **map);
+int of_dma_set_restricted_buffer(struct device *dev, struct device_node *np);
#else
static inline int of_dma_get_range(struct device_node *np,
const struct bus_dma_region **map)
{
return -ENODEV;
}
+static inline int of_dma_set_restricted_buffer(struct device *dev,
+ struct device_node *np)
+{
+ return -ENODEV;
+}
#endif
#endif /* _LINUX_OF_PRIVATE_H */
--
2.32.0.288.g62a8d224e6-goog
^ permalink raw reply related [flat|nested] 44+ messages in thread
* Re: [PATCH v15 12/12] of: Add plumbing for restricted DMA pool
2021-06-24 15:55 ` [PATCH v15 12/12] of: Add plumbing for " Claire Chang
@ 2021-07-02 3:08 ` Guenter Roeck
2021-07-02 11:39 ` Robin Murphy
0 siblings, 1 reply; 44+ messages in thread
From: Guenter Roeck @ 2021-07-02 3:08 UTC (permalink / raw)
To: Claire Chang
Cc: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross,
Christoph Hellwig, Marek Szyprowski, heikki.krogerus,
thomas.hellstrom, peterz, dri-devel, chris, grant.likely, paulus,
mingo, jxgao, sstabellini, Saravana Kannan, xypron.glpk,
Rafael J . Wysocki, Bartosz Golaszewski, bskeggs, linux-pci,
xen-devel, Thierry Reding, intel-gfx, matthew.auld,
linux-devicetree, airlied, Robin Murphy, Nicolas Boichat,
rodrigo.vivi, bhelgaas, Dan Williams, Andy Shevchenko, Greg KH,
Randy Dunlap, quic_qiancai, lkml, tfiga,
list@263.net:IOMMU DRIVERS, Jim Quinlan, thomas.lendacky,
linuxppc-dev, bauerman
Hi,
On Thu, Jun 24, 2021 at 11:55:26PM +0800, Claire Chang wrote:
> If a device is not behind an IOMMU, we look up the device node and set
> up the restricted DMA when the restricted-dma-pool is presented.
>
> Signed-off-by: Claire Chang <tientzu@chromium.org>
> Tested-by: Stefano Stabellini <sstabellini@kernel.org>
> Tested-by: Will Deacon <will@kernel.org>
With this patch in place, all sparc and sparc64 qemu emulations
fail to boot. Symptom is that the root file system is not found.
Reverting this patch fixes the problem. Bisect log is attached.
Guenter
---
# bad: [fb0ca446157a86b75502c1636b0d81e642fe6bf1] Add linux-next specific files for 20210701
# good: [62fb9874f5da54fdb243003b386128037319b219] Linux 5.13
git bisect start 'HEAD' 'v5.13'
# bad: [f63c4fda987a19b1194cc45cb72fd5bf968d9d90] Merge remote-tracking branch 'rdma/for-next'
git bisect bad f63c4fda987a19b1194cc45cb72fd5bf968d9d90
# good: [46bb5dd1d2a63e906e374e97dfd4a5e33934b1c4] Merge remote-tracking branch 'ipsec/master'
git bisect good 46bb5dd1d2a63e906e374e97dfd4a5e33934b1c4
# good: [43ba6969cfb8185353a7a6fc79070f13b9e3d6d3] Merge remote-tracking branch 'clk/clk-next'
git bisect good 43ba6969cfb8185353a7a6fc79070f13b9e3d6d3
# good: [1ca5eddcf8dca1d6345471c6404e7364af0d7019] Merge remote-tracking branch 'fuse/for-next'
git bisect good 1ca5eddcf8dca1d6345471c6404e7364af0d7019
# good: [8f6d7b3248705920187263a4e7147b0752ec7dcf] Merge remote-tracking branch 'pci/next'
git bisect good 8f6d7b3248705920187263a4e7147b0752ec7dcf
# good: [df1885a755784da3ef285f36d9230c1d090ef186] RDMA/rtrs_clt: Alloc less memory with write path fast memory registration
git bisect good df1885a755784da3ef285f36d9230c1d090ef186
# good: [93d31efb58c8ad4a66bbedbc2d082df458c04e45] Merge remote-tracking branch 'cpufreq-arm/cpufreq/arm/linux-next'
git bisect good 93d31efb58c8ad4a66bbedbc2d082df458c04e45
# good: [46308965ae6fdc7c25deb2e8c048510ae51bbe66] RDMA/irdma: Check contents of user-space irdma_mem_reg_req object
git bisect good 46308965ae6fdc7c25deb2e8c048510ae51bbe66
# good: [6de7a1d006ea9db235492b288312838d6878385f] thermal/drivers/int340x/processor_thermal: Split enumeration and processing part
git bisect good 6de7a1d006ea9db235492b288312838d6878385f
# good: [081bec2577cda3d04f6559c60b6f4e2242853520] dt-bindings: of: Add restricted DMA pool
git bisect good 081bec2577cda3d04f6559c60b6f4e2242853520
# good: [bf95ac0bcd69979af146852f6a617a60285ebbc1] Merge remote-tracking branch 'thermal/thermal/linux-next'
git bisect good bf95ac0bcd69979af146852f6a617a60285ebbc1
# good: [3d8287544223a3d2f37981c1f9ffd94d0b5e9ffc] RDMA/core: Always release restrack object
git bisect good 3d8287544223a3d2f37981c1f9ffd94d0b5e9ffc
# bad: [cff1f23fad6e0bd7d671acce0d15285c709f259c] Merge remote-tracking branch 'swiotlb/linux-next'
git bisect bad cff1f23fad6e0bd7d671acce0d15285c709f259c
# bad: [b655006619b7bccd0dc1e055bd72de5d613e7b5c] of: Add plumbing for restricted DMA pool
git bisect bad b655006619b7bccd0dc1e055bd72de5d613e7b5c
# first bad commit: [b655006619b7bccd0dc1e055bd72de5d613e7b5c] of: Add plumbing for restricted DMA pool
^ permalink raw reply [flat|nested] 44+ messages in thread
* Re: [PATCH v15 12/12] of: Add plumbing for restricted DMA pool
2021-07-02 3:08 ` Guenter Roeck
@ 2021-07-02 11:39 ` Robin Murphy
2021-07-02 13:18 ` Will Deacon
0 siblings, 1 reply; 44+ messages in thread
From: Robin Murphy @ 2021-07-02 11:39 UTC (permalink / raw)
To: Guenter Roeck, Claire Chang
Cc: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross,
Christoph Hellwig, Marek Szyprowski, heikki.krogerus,
thomas.hellstrom, peterz, dri-devel, chris, grant.likely, paulus,
mingo, jxgao, sstabellini, Saravana Kannan, xypron.glpk,
Rafael J . Wysocki, Bartosz Golaszewski, bskeggs, linux-pci,
xen-devel, Thierry Reding, intel-gfx, matthew.auld,
linux-devicetree, airlied, Nicolas Boichat, rodrigo.vivi,
bhelgaas, Dan Williams, Andy Shevchenko, Greg KH, Randy Dunlap,
quic_qiancai, lkml, tfiga, list@263.net:IOMMU DRIVERS,
Jim Quinlan, thomas.lendacky, linuxppc-dev, bauerman
On 2021-07-02 04:08, Guenter Roeck wrote:
> Hi,
>
> On Thu, Jun 24, 2021 at 11:55:26PM +0800, Claire Chang wrote:
>> If a device is not behind an IOMMU, we look up the device node and set
>> up the restricted DMA when the restricted-dma-pool is presented.
>>
>> Signed-off-by: Claire Chang <tientzu@chromium.org>
>> Tested-by: Stefano Stabellini <sstabellini@kernel.org>
>> Tested-by: Will Deacon <will@kernel.org>
>
> With this patch in place, all sparc and sparc64 qemu emulations
> fail to boot. Symptom is that the root file system is not found.
> Reverting this patch fixes the problem. Bisect log is attached.
Ah, OF_ADDRESS depends on !SPARC, so of_dma_configure_id() is presumably
returning an unexpected -ENODEV from the of_dma_set_restricted_buffer()
stub. That should probably be returning 0 instead, since either way it's
not an error condition for it to simply do nothing.
Robin.
>
> Guenter
>
> ---
> # bad: [fb0ca446157a86b75502c1636b0d81e642fe6bf1] Add linux-next specific files for 20210701
> # good: [62fb9874f5da54fdb243003b386128037319b219] Linux 5.13
> git bisect start 'HEAD' 'v5.13'
> # bad: [f63c4fda987a19b1194cc45cb72fd5bf968d9d90] Merge remote-tracking branch 'rdma/for-next'
> git bisect bad f63c4fda987a19b1194cc45cb72fd5bf968d9d90
> # good: [46bb5dd1d2a63e906e374e97dfd4a5e33934b1c4] Merge remote-tracking branch 'ipsec/master'
> git bisect good 46bb5dd1d2a63e906e374e97dfd4a5e33934b1c4
> # good: [43ba6969cfb8185353a7a6fc79070f13b9e3d6d3] Merge remote-tracking branch 'clk/clk-next'
> git bisect good 43ba6969cfb8185353a7a6fc79070f13b9e3d6d3
> # good: [1ca5eddcf8dca1d6345471c6404e7364af0d7019] Merge remote-tracking branch 'fuse/for-next'
> git bisect good 1ca5eddcf8dca1d6345471c6404e7364af0d7019
> # good: [8f6d7b3248705920187263a4e7147b0752ec7dcf] Merge remote-tracking branch 'pci/next'
> git bisect good 8f6d7b3248705920187263a4e7147b0752ec7dcf
> # good: [df1885a755784da3ef285f36d9230c1d090ef186] RDMA/rtrs_clt: Alloc less memory with write path fast memory registration
> git bisect good df1885a755784da3ef285f36d9230c1d090ef186
> # good: [93d31efb58c8ad4a66bbedbc2d082df458c04e45] Merge remote-tracking branch 'cpufreq-arm/cpufreq/arm/linux-next'
> git bisect good 93d31efb58c8ad4a66bbedbc2d082df458c04e45
> # good: [46308965ae6fdc7c25deb2e8c048510ae51bbe66] RDMA/irdma: Check contents of user-space irdma_mem_reg_req object
> git bisect good 46308965ae6fdc7c25deb2e8c048510ae51bbe66
> # good: [6de7a1d006ea9db235492b288312838d6878385f] thermal/drivers/int340x/processor_thermal: Split enumeration and processing part
> git bisect good 6de7a1d006ea9db235492b288312838d6878385f
> # good: [081bec2577cda3d04f6559c60b6f4e2242853520] dt-bindings: of: Add restricted DMA pool
> git bisect good 081bec2577cda3d04f6559c60b6f4e2242853520
> # good: [bf95ac0bcd69979af146852f6a617a60285ebbc1] Merge remote-tracking branch 'thermal/thermal/linux-next'
> git bisect good bf95ac0bcd69979af146852f6a617a60285ebbc1
> # good: [3d8287544223a3d2f37981c1f9ffd94d0b5e9ffc] RDMA/core: Always release restrack object
> git bisect good 3d8287544223a3d2f37981c1f9ffd94d0b5e9ffc
> # bad: [cff1f23fad6e0bd7d671acce0d15285c709f259c] Merge remote-tracking branch 'swiotlb/linux-next'
> git bisect bad cff1f23fad6e0bd7d671acce0d15285c709f259c
> # bad: [b655006619b7bccd0dc1e055bd72de5d613e7b5c] of: Add plumbing for restricted DMA pool
> git bisect bad b655006619b7bccd0dc1e055bd72de5d613e7b5c
> # first bad commit: [b655006619b7bccd0dc1e055bd72de5d613e7b5c] of: Add plumbing for restricted DMA pool
>
^ permalink raw reply [flat|nested] 44+ messages in thread
* Re: [PATCH v15 12/12] of: Add plumbing for restricted DMA pool
2021-07-02 11:39 ` Robin Murphy
@ 2021-07-02 13:18 ` Will Deacon
2021-07-02 13:48 ` Guenter Roeck
0 siblings, 1 reply; 44+ messages in thread
From: Will Deacon @ 2021-07-02 13:18 UTC (permalink / raw)
To: Robin Murphy
Cc: Guenter Roeck, Claire Chang, Rob Herring, mpe, Joerg Roedel,
Frank Rowand, Konrad Rzeszutek Wilk, boris.ostrovsky, jgross,
Christoph Hellwig, Marek Szyprowski, heikki.krogerus,
thomas.hellstrom, peterz, dri-devel, chris, grant.likely, paulus,
mingo, jxgao, sstabellini, Saravana Kannan, xypron.glpk,
Rafael J . Wysocki, Bartosz Golaszewski, bskeggs, linux-pci,
xen-devel, Thierry Reding, intel-gfx, matthew.auld,
linux-devicetree, airlied, Nicolas Boichat, rodrigo.vivi,
bhelgaas, Dan Williams, Andy Shevchenko, Greg KH, Randy Dunlap,
quic_qiancai, lkml, tfiga, list@263.net:IOMMU DRIVERS,
Jim Quinlan, thomas.lendacky, linuxppc-dev, bauerman
On Fri, Jul 02, 2021 at 12:39:41PM +0100, Robin Murphy wrote:
> On 2021-07-02 04:08, Guenter Roeck wrote:
> > On Thu, Jun 24, 2021 at 11:55:26PM +0800, Claire Chang wrote:
> > > If a device is not behind an IOMMU, we look up the device node and set
> > > up the restricted DMA when the restricted-dma-pool is presented.
> > >
> > > Signed-off-by: Claire Chang <tientzu@chromium.org>
> > > Tested-by: Stefano Stabellini <sstabellini@kernel.org>
> > > Tested-by: Will Deacon <will@kernel.org>
> >
> > With this patch in place, all sparc and sparc64 qemu emulations
> > fail to boot. Symptom is that the root file system is not found.
> > Reverting this patch fixes the problem. Bisect log is attached.
>
> Ah, OF_ADDRESS depends on !SPARC, so of_dma_configure_id() is presumably
> returning an unexpected -ENODEV from the of_dma_set_restricted_buffer()
> stub. That should probably be returning 0 instead, since either way it's not
> an error condition for it to simply do nothing.
Something like below?
Will
--->8
From 4d9dcb9210c1f37435b6088284e04b6b36ee8c4d Mon Sep 17 00:00:00 2001
From: Will Deacon <will@kernel.org>
Date: Fri, 2 Jul 2021 14:13:28 +0100
Subject: [PATCH] of: Return success from of_dma_set_restricted_buffer() when
!OF_ADDRESS
When CONFIG_OF_ADDRESS=n, of_dma_set_restricted_buffer() returns -ENODEV
and breaks the boot for sparc[64] machines. Return 0 instead, since the
function is essentially a glorified NOP in this configuration.
Cc: Claire Chang <tientzu@chromium.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Suggested-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/20210702030807.GA2685166@roeck-us.net
Signed-off-by: Will Deacon <will@kernel.org>
---
drivers/of/of_private.h | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/of/of_private.h b/drivers/of/of_private.h
index 8fde97565d11..34dd548c5eac 100644
--- a/drivers/of/of_private.h
+++ b/drivers/of/of_private.h
@@ -173,7 +173,8 @@ static inline int of_dma_get_range(struct device_node *np,
static inline int of_dma_set_restricted_buffer(struct device *dev,
struct device_node *np)
{
- return -ENODEV;
+ /* Do nothing, successfully. */
+ return 0;
}
#endif
--
2.32.0.93.g670b81a890-goog
^ permalink raw reply related [flat|nested] 44+ messages in thread
* Re: [PATCH v15 12/12] of: Add plumbing for restricted DMA pool
2021-07-02 13:18 ` Will Deacon
@ 2021-07-02 13:48 ` Guenter Roeck
0 siblings, 0 replies; 44+ messages in thread
From: Guenter Roeck @ 2021-07-02 13:48 UTC (permalink / raw)
To: Will Deacon, Robin Murphy
Cc: Claire Chang, Rob Herring, mpe, Joerg Roedel, Frank Rowand,
Konrad Rzeszutek Wilk, boris.ostrovsky, jgross,
Christoph Hellwig, Marek Szyprowski, heikki.krogerus,
thomas.hellstrom, peterz, dri-devel, chris, grant.likely, paulus,
mingo, jxgao, sstabellini, Saravana Kannan, xypron.glpk,
Rafael J . Wysocki, Bartosz Golaszewski, bskeggs, linux-pci,
xen-devel, Thierry Reding, intel-gfx, matthew.auld,
linux-devicetree, airlied, Nicolas Boichat, rodrigo.vivi,
bhelgaas, Dan Williams, Andy Shevchenko, Greg KH, Randy Dunlap,
quic_qiancai, lkml, tfiga, list@263.net:IOMMU DRIVERS,
Jim Quinlan, thomas.lendacky, linuxppc-dev, bauerman
On 7/2/21 6:18 AM, Will Deacon wrote:
> On Fri, Jul 02, 2021 at 12:39:41PM +0100, Robin Murphy wrote:
>> On 2021-07-02 04:08, Guenter Roeck wrote:
>>> On Thu, Jun 24, 2021 at 11:55:26PM +0800, Claire Chang wrote:
>>>> If a device is not behind an IOMMU, we look up the device node and set
>>>> up the restricted DMA when the restricted-dma-pool is presented.
>>>>
>>>> Signed-off-by: Claire Chang <tientzu@chromium.org>
>>>> Tested-by: Stefano Stabellini <sstabellini@kernel.org>
>>>> Tested-by: Will Deacon <will@kernel.org>
>>>
>>> With this patch in place, all sparc and sparc64 qemu emulations
>>> fail to boot. Symptom is that the root file system is not found.
>>> Reverting this patch fixes the problem. Bisect log is attached.
>>
>> Ah, OF_ADDRESS depends on !SPARC, so of_dma_configure_id() is presumably
>> returning an unexpected -ENODEV from the of_dma_set_restricted_buffer()
>> stub. That should probably be returning 0 instead, since either way it's not
>> an error condition for it to simply do nothing.
>
> Something like below?
>
Yes, that does the trick.
> Will
>
> --->8
>
>>From 4d9dcb9210c1f37435b6088284e04b6b36ee8c4d Mon Sep 17 00:00:00 2001
> From: Will Deacon <will@kernel.org>
> Date: Fri, 2 Jul 2021 14:13:28 +0100
> Subject: [PATCH] of: Return success from of_dma_set_restricted_buffer() when
> !OF_ADDRESS
>
> When CONFIG_OF_ADDRESS=n, of_dma_set_restricted_buffer() returns -ENODEV
> and breaks the boot for sparc[64] machines. Return 0 instead, since the
> function is essentially a glorified NOP in this configuration.
>
> Cc: Claire Chang <tientzu@chromium.org>
> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
> Reported-by: Guenter Roeck <linux@roeck-us.net>
> Suggested-by: Robin Murphy <robin.murphy@arm.com>
> Link: https://lore.kernel.org/r/20210702030807.GA2685166@roeck-us.net
> Signed-off-by: Will Deacon <will@kernel.org>
Tested-by: Guenter Roeck <linux@roeck-us.net>
> ---
> drivers/of/of_private.h | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/of/of_private.h b/drivers/of/of_private.h
> index 8fde97565d11..34dd548c5eac 100644
> --- a/drivers/of/of_private.h
> +++ b/drivers/of/of_private.h
> @@ -173,7 +173,8 @@ static inline int of_dma_get_range(struct device_node *np,
> static inline int of_dma_set_restricted_buffer(struct device *dev,
> struct device_node *np)
> {
> - return -ENODEV;
> + /* Do nothing, successfully. */
> + return 0;
> }
> #endif
>
>
^ permalink raw reply [flat|nested] 44+ messages in thread
* Re: [PATCH v15 00/12] Restricted DMA
2021-06-24 15:55 [PATCH v15 00/12] Restricted DMA Claire Chang
` (11 preceding siblings ...)
2021-06-24 15:55 ` [PATCH v15 12/12] of: Add plumbing for " Claire Chang
@ 2021-06-24 19:19 ` Konrad Rzeszutek Wilk
2021-06-25 0:41 ` Claire Chang
2021-06-25 12:30 ` Will Deacon
12 siblings, 2 replies; 44+ messages in thread
From: Konrad Rzeszutek Wilk @ 2021-06-24 19:19 UTC (permalink / raw)
To: Claire Chang
Cc: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
boris.ostrovsky, jgross, Christoph Hellwig, Marek Szyprowski,
benh, paulus, list@263.net:IOMMU DRIVERS, sstabellini,
Robin Murphy, grant.likely, xypron.glpk, Thierry Reding, mingo,
bauerman, peterz, Greg KH, Saravana Kannan, Rafael J . Wysocki,
heikki.krogerus, Andy Shevchenko, Randy Dunlap, Dan Williams,
Bartosz Golaszewski, linux-devicetree, lkml, linuxppc-dev,
xen-devel, Nicolas Boichat, Jim Quinlan, tfiga, bskeggs,
bhelgaas, chris, daniel, airlied, dri-devel, intel-gfx,
jani.nikula, jxgao, joonas.lahtinen, linux-pci,
maarten.lankhorst, matthew.auld, rodrigo.vivi, thomas.hellstrom,
thomas.lendacky, quic_qiancai
On Thu, Jun 24, 2021 at 11:55:14PM +0800, Claire Chang wrote:
> This series implements mitigations for lack of DMA access control on
> systems without an IOMMU, which could result in the DMA accessing the
> system memory at unexpected times and/or unexpected addresses, possibly
> leading to data leakage or corruption.
>
> For example, we plan to use the PCI-e bus for Wi-Fi and that PCI-e bus is
> not behind an IOMMU. As PCI-e, by design, gives the device full access to
> system memory, a vulnerability in the Wi-Fi firmware could easily escalate
> to a full system exploit (remote wifi exploits: [1a], [1b] that shows a
> full chain of exploits; [2], [3]).
>
> To mitigate the security concerns, we introduce restricted DMA. Restricted
> DMA utilizes the existing swiotlb to bounce streaming DMA in and out of a
> specially allocated region and does memory allocation from the same region.
> The feature on its own provides a basic level of protection against the DMA
> overwriting buffer contents at unexpected times. However, to protect
> against general data leakage and system memory corruption, the system needs
> to provide a way to restrict the DMA to a predefined memory region (this is
> usually done at firmware level, e.g. MPU in ATF on some ARM platforms [4]).
>
> [1a] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_4.html
> [1b] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_11.html
> [2] https://blade.tencent.com/en/advisories/qualpwn/
> [3] https://www.bleepingcomputer.com/news/security/vulnerabilities-found-in-highly-popular-firmware-for-wifi-chips/
> [4] https://github.com/ARM-software/arm-trusted-firmware/blob/master/plat/mediatek/mt8183/drivers/emi_mpu/emi_mpu.c#L132
>
> v15:
> - Apply Will's diff (https://lore.kernel.org/patchwork/patch/1448957/#1647521)
> to fix the crash reported by Qian.
> - Add Stefano's Acked-by tag for patch 01/12 from v14
That all should be now be on
https://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb.git/
devel/for-linus-5.14 (and linux-next)
^ permalink raw reply [flat|nested] 44+ messages in thread
* Re: [PATCH v15 00/12] Restricted DMA
2021-06-24 19:19 ` [PATCH v15 00/12] Restricted DMA Konrad Rzeszutek Wilk
@ 2021-06-25 0:41 ` Claire Chang
2021-06-25 12:30 ` Will Deacon
1 sibling, 0 replies; 44+ messages in thread
From: Claire Chang @ 2021-06-25 0:41 UTC (permalink / raw)
To: Konrad Rzeszutek Wilk
Cc: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
boris.ostrovsky, jgross, Christoph Hellwig, Marek Szyprowski,
benh, paulus, list@263.net:IOMMU DRIVERS, Stefano Stabellini,
Robin Murphy, grant.likely, xypron.glpk, Thierry Reding, mingo,
bauerman, peterz, Greg KH, Saravana Kannan, Rafael J . Wysocki,
heikki.krogerus, Andy Shevchenko, Randy Dunlap, Dan Williams,
Bartosz Golaszewski, linux-devicetree, lkml, linuxppc-dev,
xen-devel, Nicolas Boichat, Jim Quinlan, Tomasz Figa, bskeggs,
Bjorn Helgaas, chris, Daniel Vetter, airlied, dri-devel,
intel-gfx, jani.nikula, Jianxiong Gao, joonas.lahtinen,
linux-pci, maarten.lankhorst, matthew.auld, rodrigo.vivi,
thomas.hellstrom, Tom Lendacky, Qian Cai
On Fri, Jun 25, 2021 at 3:20 AM Konrad Rzeszutek Wilk
<konrad.wilk@oracle.com> wrote:
>
> On Thu, Jun 24, 2021 at 11:55:14PM +0800, Claire Chang wrote:
> > This series implements mitigations for lack of DMA access control on
> > systems without an IOMMU, which could result in the DMA accessing the
> > system memory at unexpected times and/or unexpected addresses, possibly
> > leading to data leakage or corruption.
> >
> > For example, we plan to use the PCI-e bus for Wi-Fi and that PCI-e bus is
> > not behind an IOMMU. As PCI-e, by design, gives the device full access to
> > system memory, a vulnerability in the Wi-Fi firmware could easily escalate
> > to a full system exploit (remote wifi exploits: [1a], [1b] that shows a
> > full chain of exploits; [2], [3]).
> >
> > To mitigate the security concerns, we introduce restricted DMA. Restricted
> > DMA utilizes the existing swiotlb to bounce streaming DMA in and out of a
> > specially allocated region and does memory allocation from the same region.
> > The feature on its own provides a basic level of protection against the DMA
> > overwriting buffer contents at unexpected times. However, to protect
> > against general data leakage and system memory corruption, the system needs
> > to provide a way to restrict the DMA to a predefined memory region (this is
> > usually done at firmware level, e.g. MPU in ATF on some ARM platforms [4]).
> >
> > [1a] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_4.html
> > [1b] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_11.html
> > [2] https://blade.tencent.com/en/advisories/qualpwn/
> > [3] https://www.bleepingcomputer.com/news/security/vulnerabilities-found-in-highly-popular-firmware-for-wifi-chips/
> > [4] https://github.com/ARM-software/arm-trusted-firmware/blob/master/plat/mediatek/mt8183/drivers/emi_mpu/emi_mpu.c#L132
> >
> > v15:
> > - Apply Will's diff (https://lore.kernel.org/patchwork/patch/1448957/#1647521)
> > to fix the crash reported by Qian.
> > - Add Stefano's Acked-by tag for patch 01/12 from v14
>
> That all should be now be on
>
> https://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb.git/
> devel/for-linus-5.14 (and linux-next)
>
devel/for-linus-5.14 looks good. Thanks!
^ permalink raw reply [flat|nested] 44+ messages in thread
* Re: [PATCH v15 00/12] Restricted DMA
2021-06-24 19:19 ` [PATCH v15 00/12] Restricted DMA Konrad Rzeszutek Wilk
2021-06-25 0:41 ` Claire Chang
@ 2021-06-25 12:30 ` Will Deacon
1 sibling, 0 replies; 44+ messages in thread
From: Will Deacon @ 2021-06-25 12:30 UTC (permalink / raw)
To: Konrad Rzeszutek Wilk
Cc: Claire Chang, Rob Herring, mpe, Joerg Roedel, Frank Rowand,
boris.ostrovsky, jgross, Christoph Hellwig, Marek Szyprowski,
benh, paulus, list@263.net:IOMMU DRIVERS, sstabellini,
Robin Murphy, grant.likely, xypron.glpk, Thierry Reding, mingo,
bauerman, peterz, Greg KH, Saravana Kannan, Rafael J . Wysocki,
heikki.krogerus, Andy Shevchenko, Randy Dunlap, Dan Williams,
Bartosz Golaszewski, linux-devicetree, lkml, linuxppc-dev,
xen-devel, Nicolas Boichat, Jim Quinlan, tfiga, bskeggs,
bhelgaas, chris, daniel, airlied, dri-devel, intel-gfx,
jani.nikula, jxgao, joonas.lahtinen, linux-pci,
maarten.lankhorst, matthew.auld, rodrigo.vivi, thomas.hellstrom,
thomas.lendacky, quic_qiancai
On Thu, Jun 24, 2021 at 03:19:48PM -0400, Konrad Rzeszutek Wilk wrote:
> On Thu, Jun 24, 2021 at 11:55:14PM +0800, Claire Chang wrote:
> > This series implements mitigations for lack of DMA access control on
> > systems without an IOMMU, which could result in the DMA accessing the
> > system memory at unexpected times and/or unexpected addresses, possibly
> > leading to data leakage or corruption.
> >
> > For example, we plan to use the PCI-e bus for Wi-Fi and that PCI-e bus is
> > not behind an IOMMU. As PCI-e, by design, gives the device full access to
> > system memory, a vulnerability in the Wi-Fi firmware could easily escalate
> > to a full system exploit (remote wifi exploits: [1a], [1b] that shows a
> > full chain of exploits; [2], [3]).
> >
> > To mitigate the security concerns, we introduce restricted DMA. Restricted
> > DMA utilizes the existing swiotlb to bounce streaming DMA in and out of a
> > specially allocated region and does memory allocation from the same region.
> > The feature on its own provides a basic level of protection against the DMA
> > overwriting buffer contents at unexpected times. However, to protect
> > against general data leakage and system memory corruption, the system needs
> > to provide a way to restrict the DMA to a predefined memory region (this is
> > usually done at firmware level, e.g. MPU in ATF on some ARM platforms [4]).
> >
> > [1a] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_4.html
> > [1b] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_11.html
> > [2] https://blade.tencent.com/en/advisories/qualpwn/
> > [3] https://www.bleepingcomputer.com/news/security/vulnerabilities-found-in-highly-popular-firmware-for-wifi-chips/
> > [4] https://github.com/ARM-software/arm-trusted-firmware/blob/master/plat/mediatek/mt8183/drivers/emi_mpu/emi_mpu.c#L132
> >
> > v15:
> > - Apply Will's diff (https://lore.kernel.org/patchwork/patch/1448957/#1647521)
> > to fix the crash reported by Qian.
> > - Add Stefano's Acked-by tag for patch 01/12 from v14
>
> That all should be now be on
>
> https://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb.git/
> devel/for-linus-5.14 (and linux-next)
Thanks Konrad!
Will
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