[PATCH v3 00/41] cxlflash: OCXL transport support and miscellaneous fixes

[PATCH v3 00/41] cxlflash: OCXL transport support and miscellaneous fixes

[Uma Krishnan]

This patch series adds OCXL support to the cxlflash driver. With this
support, new devices using the OCXL transport will be supported by the
cxlflash driver along with the existing CXL devices. An effort is made
to keep this transport specific function independent of the existing
core driver that communicates with the AFU.

The first three patches contain a minor fix and staging improvements.

This series is intended for 4.17 and is bisectable.

v3 Changes:
- Addressed comments by Frederic Barrat
- Resolved IDR initialization bug
- Properly identify functions that do not have an AFU defined
- Added 3 new patches to the end of the series which resolve corner cases

v2 Changes:
- Replaced OpenCXL with OCXL in the commit messages and comments

Matthew R. Ochs (1):
  cxlflash: Avoid clobbering context control register value

Uma Krishnan (40):
  cxlflash: Preserve number of interrupts for master contexts
  cxlflash: Add argument identifier names
  cxlflash: Introduce OCXL backend
  cxlflash: Hardware AFU for OCXL
  cxlflash: Read host function configuration
  cxlflash: Setup function acTag range
  cxlflash: Read host AFU configuration
  cxlflash: Setup AFU acTag range
  cxlflash: Setup AFU PASID
  cxlflash: Adapter context support for OCXL
  cxlflash: Use IDR to manage adapter contexts
  cxlflash: Support adapter file descriptors for OCXL
  cxlflash: Support adapter context discovery
  cxlflash: Support image reload policy modification
  cxlflash: MMIO map the AFU
  cxlflash: Support starting an adapter context
  cxlflash: Support process specific mappings
  cxlflash: Support AFU state toggling
  cxlflash: Support reading adapter VPD data
  cxlflash: Setup function OCXL link
  cxlflash: Setup OCXL transaction layer
  cxlflash: Support process element lifecycle
  cxlflash: Support AFU interrupt management
  cxlflash: Support AFU interrupt mapping and registration
  cxlflash: Support starting user contexts
  cxlflash: Support adapter context polling
  cxlflash: Support adapter context reading
  cxlflash: Support adapter context mmap and release
  cxlflash: Support file descriptor mapping
  cxlflash: Introduce object handle fop
  cxlflash: Setup LISNs for user contexts
  cxlflash: Setup LISNs for master contexts
  cxlflash: Update synchronous interrupt status bits
  cxlflash: Introduce OCXL context state machine
  cxlflash: Register for translation errors
  cxlflash: Support AFU reset
  cxlflash: Enable OCXL operations
  cxlflash: Synchronize reset and remove ops
  cxlflash: Remove commmands from pending list on timeout
  cxlflash: Handle spurious interrupts

 drivers/scsi/cxlflash/Kconfig     |    2 +-
 drivers/scsi/cxlflash/Makefile    |    2 +-
 drivers/scsi/cxlflash/backend.h   |   50 +-
 drivers/scsi/cxlflash/common.h    |   11 +-
 drivers/scsi/cxlflash/cxl_hw.c    |   13 +
 drivers/scsi/cxlflash/main.c      |   86 ++-
 drivers/scsi/cxlflash/main.h      |    1 +
 drivers/scsi/cxlflash/ocxl_hw.c   | 1436 +++++++++++++++++++++++++++++++++++++
 drivers/scsi/cxlflash/ocxl_hw.h   |   77 ++
 drivers/scsi/cxlflash/sislite.h   |   41 +-
 drivers/scsi/cxlflash/superpipe.c |   14 +
 11 files changed, 1682 insertions(+), 51 deletions(-)
 create mode 100644 drivers/scsi/cxlflash/ocxl_hw.c
 create mode 100644 drivers/scsi/cxlflash/ocxl_hw.h

-- 
2.1.0

[PATCH v3 00/41] cxlflash: OCXL transport support and miscellaneous fixes

[Uma Krishnan]

This patch series adds OCXL support to the cxlflash driver. With this
support, new devices using the OCXL transport will be supported by the
cxlflash driver along with the existing CXL devices. An effort is made
to keep this transport specific function independent of the existing
core driver that communicates with the AFU.

The first three patches contain a minor fix and staging improvements.

This series is intended for 4.17 and is bisectable.

v3 Changes:
- Addressed comments by Frederic Barrat
- Resolved IDR initialization bug
- Properly identify functions that do not have an AFU defined
- Added 3 new patches to the end of the series which resolve corner cases

v2 Changes:
- Replaced OpenCXL with OCXL in the commit messages and comments

Matthew R. Ochs (1):
  cxlflash: Avoid clobbering context control register value

Uma Krishnan (40):
  cxlflash: Preserve number of interrupts for master contexts
  cxlflash: Add argument identifier names
  cxlflash: Introduce OCXL backend
  cxlflash: Hardware AFU for OCXL
  cxlflash: Read host function configuration
  cxlflash: Setup function acTag range
  cxlflash: Read host AFU configuration
  cxlflash: Setup AFU acTag range
  cxlflash: Setup AFU PASID
  cxlflash: Adapter context support for OCXL
  cxlflash: Use IDR to manage adapter contexts
  cxlflash: Support adapter file descriptors for OCXL
  cxlflash: Support adapter context discovery
  cxlflash: Support image reload policy modification
  cxlflash: MMIO map the AFU
  cxlflash: Support starting an adapter context
  cxlflash: Support process specific mappings
  cxlflash: Support AFU state toggling
  cxlflash: Support reading adapter VPD data
  cxlflash: Setup function OCXL link
  cxlflash: Setup OCXL transaction layer
  cxlflash: Support process element lifecycle
  cxlflash: Support AFU interrupt management
  cxlflash: Support AFU interrupt mapping and registration
  cxlflash: Support starting user contexts
  cxlflash: Support adapter context polling
  cxlflash: Support adapter context reading
  cxlflash: Support adapter context mmap and release
  cxlflash: Support file descriptor mapping
  cxlflash: Introduce object handle fop
  cxlflash: Setup LISNs for user contexts
  cxlflash: Setup LISNs for master contexts
  cxlflash: Update synchronous interrupt status bits
  cxlflash: Introduce OCXL context state machine
  cxlflash: Register for translation errors
  cxlflash: Support AFU reset
  cxlflash: Enable OCXL operations
  cxlflash: Synchronize reset and remove ops
  cxlflash: Remove commmands from pending list on timeout
  cxlflash: Handle spurious interrupts

 drivers/scsi/cxlflash/Kconfig     |    2 +-
 drivers/scsi/cxlflash/Makefile    |    2 +-
 drivers/scsi/cxlflash/backend.h   |   50 +-
 drivers/scsi/cxlflash/common.h    |   11 +-
 drivers/scsi/cxlflash/cxl_hw.c    |   13 +
 drivers/scsi/cxlflash/main.c      |   86 ++-
 drivers/scsi/cxlflash/main.h      |    1 +
 drivers/scsi/cxlflash/ocxl_hw.c   | 1436 +++++++++++++++++++++++++++++++++++++
 drivers/scsi/cxlflash/ocxl_hw.h   |   77 ++
 drivers/scsi/cxlflash/sislite.h   |   41 +-
 drivers/scsi/cxlflash/superpipe.c |   14 +
 11 files changed, 1682 insertions(+), 51 deletions(-)
 create mode 100644 drivers/scsi/cxlflash/ocxl_hw.c
 create mode 100644 drivers/scsi/cxlflash/ocxl_hw.h

-- 
2.1.0

[PATCH v3 01/41] cxlflash: Preserve number of interrupts for master contexts

[Uma Krishnan]

The number of interrupts requested for user contexts are stored in the
context specific structures and utilized to manage the interrupts. For the
master contexts, this number is only used once and therefore not saved.

To prepare for future commits where the number of interrupts will be
required in more than one place, preserve the value in the master context
structure.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/common.h |  1 +
 drivers/scsi/cxlflash/main.c   | 11 ++++++++---
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/cxlflash/common.h b/drivers/scsi/cxlflash/common.h
index 102fd26..5d7ca01 100644
--- a/drivers/scsi/cxlflash/common.h
+++ b/drivers/scsi/cxlflash/common.h
@@ -211,6 +211,7 @@ struct hwq {
 	struct sisl_ctrl_map __iomem *ctrl_map;		/* MC control map */
 	ctx_hndl_t ctx_hndl;	/* master's context handle */
 	u32 index;		/* Index of this hwq */
+	int num_irqs;		/* Numer of interrupts requested for context */
 	struct list_head pending_cmds;	/* Commands pending completion */
 
 	atomic_t hsq_credits;
diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c
index d8fe7ab8..3d3e003 100644
--- a/drivers/scsi/cxlflash/main.c
+++ b/drivers/scsi/cxlflash/main.c
@@ -1911,7 +1911,7 @@ static enum undo_level init_intr(struct cxlflash_cfg *cfg,
 	int rc = 0;
 	enum undo_level level = UNDO_NOOP;
 	bool is_primary_hwq = (hwq->index == PRIMARY_HWQ);
-	int num_irqs = is_primary_hwq ? 3 : 2;
+	int num_irqs = hwq->num_irqs;
 
 	rc = cfg->ops->allocate_afu_irqs(ctx, num_irqs);
 	if (unlikely(rc)) {
@@ -1965,16 +1965,20 @@ static int init_mc(struct cxlflash_cfg *cfg, u32 index)
 	struct device *dev = &cfg->dev->dev;
 	struct hwq *hwq = get_hwq(cfg->afu, index);
 	int rc = 0;
+	int num_irqs;
 	enum undo_level level;
 
 	hwq->afu = cfg->afu;
 	hwq->index = index;
 	INIT_LIST_HEAD(&hwq->pending_cmds);
 
-	if (index == PRIMARY_HWQ)
+	if (index == PRIMARY_HWQ) {
 		ctx = cfg->ops->get_context(cfg->dev, cfg->afu_cookie);
-	else
+		num_irqs = 3;
+	} else {
 		ctx = cfg->ops->dev_context_init(cfg->dev, cfg->afu_cookie);
+		num_irqs = 2;
+	}
 	if (IS_ERR_OR_NULL(ctx)) {
 		rc = -ENOMEM;
 		goto err1;
@@ -1982,6 +1986,7 @@ static int init_mc(struct cxlflash_cfg *cfg, u32 index)
 
 	WARN_ON(hwq->ctx_cookie);
 	hwq->ctx_cookie = ctx;
+	hwq->num_irqs = num_irqs;
 
 	/* Set it up as a master with the CXL */
 	cfg->ops->set_master(ctx);
-- 
2.1.0

[PATCH v3 01/41] cxlflash: Preserve number of interrupts for master contexts

[Uma Krishnan]

The number of interrupts requested for user contexts are stored in the
context specific structures and utilized to manage the interrupts. For the
master contexts, this number is only used once and therefore not saved.

To prepare for future commits where the number of interrupts will be
required in more than one place, preserve the value in the master context
structure.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/common.h |  1 +
 drivers/scsi/cxlflash/main.c   | 11 ++++++++---
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/cxlflash/common.h b/drivers/scsi/cxlflash/common.h
index 102fd26..5d7ca01 100644
--- a/drivers/scsi/cxlflash/common.h
+++ b/drivers/scsi/cxlflash/common.h
@@ -211,6 +211,7 @@ struct hwq {
 	struct sisl_ctrl_map __iomem *ctrl_map;		/* MC control map */
 	ctx_hndl_t ctx_hndl;	/* master's context handle */
 	u32 index;		/* Index of this hwq */
+	int num_irqs;		/* Numer of interrupts requested for context */
 	struct list_head pending_cmds;	/* Commands pending completion */
 
 	atomic_t hsq_credits;
diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c
index d8fe7ab8..3d3e003 100644
--- a/drivers/scsi/cxlflash/main.c
+++ b/drivers/scsi/cxlflash/main.c
@@ -1911,7 +1911,7 @@ static enum undo_level init_intr(struct cxlflash_cfg *cfg,
 	int rc = 0;
 	enum undo_level level = UNDO_NOOP;
 	bool is_primary_hwq = (hwq->index == PRIMARY_HWQ);
-	int num_irqs = is_primary_hwq ? 3 : 2;
+	int num_irqs = hwq->num_irqs;
 
 	rc = cfg->ops->allocate_afu_irqs(ctx, num_irqs);
 	if (unlikely(rc)) {
@@ -1965,16 +1965,20 @@ static int init_mc(struct cxlflash_cfg *cfg, u32 index)
 	struct device *dev = &cfg->dev->dev;
 	struct hwq *hwq = get_hwq(cfg->afu, index);
 	int rc = 0;
+	int num_irqs;
 	enum undo_level level;
 
 	hwq->afu = cfg->afu;
 	hwq->index = index;
 	INIT_LIST_HEAD(&hwq->pending_cmds);
 
-	if (index == PRIMARY_HWQ)
+	if (index == PRIMARY_HWQ) {
 		ctx = cfg->ops->get_context(cfg->dev, cfg->afu_cookie);
-	else
+		num_irqs = 3;
+	} else {
 		ctx = cfg->ops->dev_context_init(cfg->dev, cfg->afu_cookie);
+		num_irqs = 2;
+	}
 	if (IS_ERR_OR_NULL(ctx)) {
 		rc = -ENOMEM;
 		goto err1;
@@ -1982,6 +1986,7 @@ static int init_mc(struct cxlflash_cfg *cfg, u32 index)
 
 	WARN_ON(hwq->ctx_cookie);
 	hwq->ctx_cookie = ctx;
+	hwq->num_irqs = num_irqs;
 
 	/* Set it up as a master with the CXL */
 	cfg->ops->set_master(ctx);
-- 
2.1.0

[PATCH v3 02/41] cxlflash: Avoid clobbering context control register value

[Uma Krishnan]

From: "Matthew R. Ochs" <mrochs@linux.vnet.ibm.com>

The SISLite specification originally defined the context control
register with a single field of bits to represent the LISN and
also stipulated that the register reset value be 0. The cxlflash
driver took advantage of this when programming the LISN for the
master contexts via an unconditional write - no other bits were
preserved.

When unmap support was added, SISLite was updated to define bit
0 of the context control register as a way for the AFU to notify
the context owner that unmap operations were supported. Thus the
assumptions under which the register is setup changed and the
existing unconditional write is clobbering the unmap state for
master contexts. This is presently not an issue due to the order
in which the context control register is programmed in relation to
the unmap bit being queried but should be addressed to avoid a
future regression in the event this code is moved elsewhere.

To remedy this issue, preserve the bits when programming the LISN
field in the context control register. Since the LISN will now be
programmed using a read value, assert that the initial state of the
LISN field is as described in SISLite (0).

Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/main.c    | 5 ++++-
 drivers/scsi/cxlflash/sislite.h | 1 +
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c
index 3d3e003..b83a55a 100644
--- a/drivers/scsi/cxlflash/main.c
+++ b/drivers/scsi/cxlflash/main.c
@@ -1303,7 +1303,10 @@ static void afu_err_intr_init(struct afu *afu)
 	for (i = 0; i < afu->num_hwqs; i++) {
 		hwq = get_hwq(afu, i);
 
-		writeq_be(SISL_MSI_SYNC_ERROR, &hwq->host_map->ctx_ctrl);
+		reg = readq_be(&hwq->host_map->ctx_ctrl);
+		WARN_ON((reg & SISL_CTX_CTRL_LISN_MASK) != 0);
+		reg |= SISL_MSI_SYNC_ERROR;
+		writeq_be(reg, &hwq->host_map->ctx_ctrl);
 		writeq_be(SISL_ISTATUS_MASK, &hwq->host_map->intr_mask);
 	}
 }
diff --git a/drivers/scsi/cxlflash/sislite.h b/drivers/scsi/cxlflash/sislite.h
index bedf1ce..d8940f1 100644
--- a/drivers/scsi/cxlflash/sislite.h
+++ b/drivers/scsi/cxlflash/sislite.h
@@ -284,6 +284,7 @@ struct sisl_host_map {
 	__be64 cmd_room;
 	__be64 ctx_ctrl;	/* least significant byte or b56:63 is LISN# */
 #define SISL_CTX_CTRL_UNMAP_SECTOR	0x8000000000000000ULL /* b0 */
+#define SISL_CTX_CTRL_LISN_MASK		(0xFFULL)
 	__be64 mbox_w;		/* restricted use */
 	__be64 sq_start;	/* Submission Queue (R/W): write sequence and */
 	__be64 sq_end;		/* inclusion semantics are the same as RRQ    */
-- 
2.1.0

[PATCH v3 02/41] cxlflash: Avoid clobbering context control register value

[Uma Krishnan]

From: "Matthew R. Ochs" <mrochs@linux.vnet.ibm.com>

The SISLite specification originally defined the context control
register with a single field of bits to represent the LISN and
also stipulated that the register reset value be 0. The cxlflash
driver took advantage of this when programming the LISN for the
master contexts via an unconditional write - no other bits were
preserved.

When unmap support was added, SISLite was updated to define bit
0 of the context control register as a way for the AFU to notify
the context owner that unmap operations were supported. Thus the
assumptions under which the register is setup changed and the
existing unconditional write is clobbering the unmap state for
master contexts. This is presently not an issue due to the order
in which the context control register is programmed in relation to
the unmap bit being queried but should be addressed to avoid a
future regression in the event this code is moved elsewhere.

To remedy this issue, preserve the bits when programming the LISN
field in the context control register. Since the LISN will now be
programmed using a read value, assert that the initial state of the
LISN field is as described in SISLite (0).

Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/main.c    | 5 ++++-
 drivers/scsi/cxlflash/sislite.h | 1 +
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c
index 3d3e003..b83a55a 100644
--- a/drivers/scsi/cxlflash/main.c
+++ b/drivers/scsi/cxlflash/main.c
@@ -1303,7 +1303,10 @@ static void afu_err_intr_init(struct afu *afu)
 	for (i = 0; i < afu->num_hwqs; i++) {
 		hwq = get_hwq(afu, i);
 
-		writeq_be(SISL_MSI_SYNC_ERROR, &hwq->host_map->ctx_ctrl);
+		reg = readq_be(&hwq->host_map->ctx_ctrl);
+		WARN_ON((reg & SISL_CTX_CTRL_LISN_MASK) != 0);
+		reg |= SISL_MSI_SYNC_ERROR;
+		writeq_be(reg, &hwq->host_map->ctx_ctrl);
 		writeq_be(SISL_ISTATUS_MASK, &hwq->host_map->intr_mask);
 	}
 }
diff --git a/drivers/scsi/cxlflash/sislite.h b/drivers/scsi/cxlflash/sislite.h
index bedf1ce..d8940f1 100644
--- a/drivers/scsi/cxlflash/sislite.h
+++ b/drivers/scsi/cxlflash/sislite.h
@@ -284,6 +284,7 @@ struct sisl_host_map {
 	__be64 cmd_room;
 	__be64 ctx_ctrl;	/* least significant byte or b56:63 is LISN# */
 #define SISL_CTX_CTRL_UNMAP_SECTOR	0x8000000000000000ULL /* b0 */
+#define SISL_CTX_CTRL_LISN_MASK		(0xFFULL)
 	__be64 mbox_w;		/* restricted use */
 	__be64 sq_start;	/* Submission Queue (R/W): write sequence and */
 	__be64 sq_end;		/* inclusion semantics are the same as RRQ    */
-- 
2.1.0

[PATCH v3 03/41] cxlflash: Add argument identifier names

[Uma Krishnan]

Checkpatch throws a warning when the argument identifier names are not
included in the function definitions.

To avoid these warnings, argument identifiers are added in the existing
function definitions.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/backend.h | 47 ++++++++++++++++++++++-------------------
 drivers/scsi/cxlflash/common.h  |  4 ++--
 2 files changed, 27 insertions(+), 24 deletions(-)

diff --git a/drivers/scsi/cxlflash/backend.h b/drivers/scsi/cxlflash/backend.h
index 339e42b..7b72149 100644
--- a/drivers/scsi/cxlflash/backend.h
+++ b/drivers/scsi/cxlflash/backend.h
@@ -16,26 +16,29 @@ extern const struct cxlflash_backend_ops cxlflash_cxl_ops;
 
 struct cxlflash_backend_ops {
 	struct module *module;
-	void __iomem * (*psa_map)(void *);
-	void (*psa_unmap)(void __iomem *);
-	int (*process_element)(void *);
-	int (*map_afu_irq)(void *, int, irq_handler_t, void *, char *);
-	void (*unmap_afu_irq)(void *, int, void *);
-	int (*start_context)(void *);
-	int (*stop_context)(void *);
-	int (*afu_reset)(void *);
-	void (*set_master)(void *);
-	void * (*get_context)(struct pci_dev *, void *);
-	void * (*dev_context_init)(struct pci_dev *, void *);
-	int (*release_context)(void *);
-	void (*perst_reloads_same_image)(void *, bool);
-	ssize_t (*read_adapter_vpd)(struct pci_dev *, void *, size_t);
-	int (*allocate_afu_irqs)(void *, int);
-	void (*free_afu_irqs)(void *);
-	void * (*create_afu)(struct pci_dev *);
-	struct file * (*get_fd)(void *, struct file_operations *, int *);
-	void * (*fops_get_context)(struct file *);
-	int (*start_work)(void *, u64);
-	int (*fd_mmap)(struct file *, struct vm_area_struct *);
-	int (*fd_release)(struct inode *, struct file *);
+	void __iomem * (*psa_map)(void *ctx_cookie);
+	void (*psa_unmap)(void __iomem *addr);
+	int (*process_element)(void *ctx_cookie);
+	int (*map_afu_irq)(void *ctx_cookie, int num, irq_handler_t handler,
+			   void *cookie, char *name);
+	void (*unmap_afu_irq)(void *ctx_cookie, int num, void *cookie);
+	int (*start_context)(void *ctx_cookie);
+	int (*stop_context)(void *ctx_cookie);
+	int (*afu_reset)(void *ctx_cookie);
+	void (*set_master)(void *ctx_cookie);
+	void * (*get_context)(struct pci_dev *dev, void *afu_cookie);
+	void * (*dev_context_init)(struct pci_dev *dev, void *afu_cookie);
+	int (*release_context)(void *ctx_cookie);
+	void (*perst_reloads_same_image)(void *afu_cookie, bool image);
+	ssize_t (*read_adapter_vpd)(struct pci_dev *dev, void *buf,
+				    size_t count);
+	int (*allocate_afu_irqs)(void *ctx_cookie, int num);
+	void (*free_afu_irqs)(void *ctx_cookie);
+	void * (*create_afu)(struct pci_dev *dev);
+	struct file * (*get_fd)(void *ctx_cookie, struct file_operations *fops,
+				int *fd);
+	void * (*fops_get_context)(struct file *file);
+	int (*start_work)(void *ctx_cookie, u64 irqs);
+	int (*fd_mmap)(struct file *file, struct vm_area_struct *vm);
+	int (*fd_release)(struct inode *inode, struct file *file);
 };
diff --git a/drivers/scsi/cxlflash/common.h b/drivers/scsi/cxlflash/common.h
index 5d7ca01..d7fccea 100644
--- a/drivers/scsi/cxlflash/common.h
+++ b/drivers/scsi/cxlflash/common.h
@@ -232,8 +232,8 @@ struct hwq {
 
 struct afu {
 	struct hwq hwqs[CXLFLASH_MAX_HWQS];
-	int (*send_cmd)(struct afu *, struct afu_cmd *);
-	int (*context_reset)(struct hwq *);
+	int (*send_cmd)(struct afu *afu, struct afu_cmd *cmd);
+	int (*context_reset)(struct hwq *hwq);
 
 	/* AFU HW */
 	struct cxlflash_afu_map __iomem *afu_map;	/* entire MMIO map */
-- 
2.1.0

[PATCH v3 03/41] cxlflash: Add argument identifier names

[Uma Krishnan]

Checkpatch throws a warning when the argument identifier names are not
included in the function definitions.

To avoid these warnings, argument identifiers are added in the existing
function definitions.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/backend.h | 47 ++++++++++++++++++++++-------------------
 drivers/scsi/cxlflash/common.h  |  4 ++--
 2 files changed, 27 insertions(+), 24 deletions(-)

diff --git a/drivers/scsi/cxlflash/backend.h b/drivers/scsi/cxlflash/backend.h
index 339e42b..7b72149 100644
--- a/drivers/scsi/cxlflash/backend.h
+++ b/drivers/scsi/cxlflash/backend.h
@@ -16,26 +16,29 @@ extern const struct cxlflash_backend_ops cxlflash_cxl_ops;
 
 struct cxlflash_backend_ops {
 	struct module *module;
-	void __iomem * (*psa_map)(void *);
-	void (*psa_unmap)(void __iomem *);
-	int (*process_element)(void *);
-	int (*map_afu_irq)(void *, int, irq_handler_t, void *, char *);
-	void (*unmap_afu_irq)(void *, int, void *);
-	int (*start_context)(void *);
-	int (*stop_context)(void *);
-	int (*afu_reset)(void *);
-	void (*set_master)(void *);
-	void * (*get_context)(struct pci_dev *, void *);
-	void * (*dev_context_init)(struct pci_dev *, void *);
-	int (*release_context)(void *);
-	void (*perst_reloads_same_image)(void *, bool);
-	ssize_t (*read_adapter_vpd)(struct pci_dev *, void *, size_t);
-	int (*allocate_afu_irqs)(void *, int);
-	void (*free_afu_irqs)(void *);
-	void * (*create_afu)(struct pci_dev *);
-	struct file * (*get_fd)(void *, struct file_operations *, int *);
-	void * (*fops_get_context)(struct file *);
-	int (*start_work)(void *, u64);
-	int (*fd_mmap)(struct file *, struct vm_area_struct *);
-	int (*fd_release)(struct inode *, struct file *);
+	void __iomem * (*psa_map)(void *ctx_cookie);
+	void (*psa_unmap)(void __iomem *addr);
+	int (*process_element)(void *ctx_cookie);
+	int (*map_afu_irq)(void *ctx_cookie, int num, irq_handler_t handler,
+			   void *cookie, char *name);
+	void (*unmap_afu_irq)(void *ctx_cookie, int num, void *cookie);
+	int (*start_context)(void *ctx_cookie);
+	int (*stop_context)(void *ctx_cookie);
+	int (*afu_reset)(void *ctx_cookie);
+	void (*set_master)(void *ctx_cookie);
+	void * (*get_context)(struct pci_dev *dev, void *afu_cookie);
+	void * (*dev_context_init)(struct pci_dev *dev, void *afu_cookie);
+	int (*release_context)(void *ctx_cookie);
+	void (*perst_reloads_same_image)(void *afu_cookie, bool image);
+	ssize_t (*read_adapter_vpd)(struct pci_dev *dev, void *buf,
+				    size_t count);
+	int (*allocate_afu_irqs)(void *ctx_cookie, int num);
+	void (*free_afu_irqs)(void *ctx_cookie);
+	void * (*create_afu)(struct pci_dev *dev);
+	struct file * (*get_fd)(void *ctx_cookie, struct file_operations *fops,
+				int *fd);
+	void * (*fops_get_context)(struct file *file);
+	int (*start_work)(void *ctx_cookie, u64 irqs);
+	int (*fd_mmap)(struct file *file, struct vm_area_struct *vm);
+	int (*fd_release)(struct inode *inode, struct file *file);
 };
diff --git a/drivers/scsi/cxlflash/common.h b/drivers/scsi/cxlflash/common.h
index 5d7ca01..d7fccea 100644
--- a/drivers/scsi/cxlflash/common.h
+++ b/drivers/scsi/cxlflash/common.h
@@ -232,8 +232,8 @@ struct hwq {
 
 struct afu {
 	struct hwq hwqs[CXLFLASH_MAX_HWQS];
-	int (*send_cmd)(struct afu *, struct afu_cmd *);
-	int (*context_reset)(struct hwq *);
+	int (*send_cmd)(struct afu *afu, struct afu_cmd *cmd);
+	int (*context_reset)(struct hwq *hwq);
 
 	/* AFU HW */
 	struct cxlflash_afu_map __iomem *afu_map;	/* entire MMIO map */
-- 
2.1.0

[PATCH v3 04/41] cxlflash: Introduce OCXL backend

[Uma Krishnan]

Add initial infrastructure to support a new cxlflash transport, OCXL.

Claim a dependency on OCXL and add a new file, ocxl_hw.c, which will host
the backend routines that are specific to OCXL.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
---
 drivers/scsi/cxlflash/Kconfig   |  2 +-
 drivers/scsi/cxlflash/Makefile  |  2 +-
 drivers/scsi/cxlflash/backend.h |  1 +
 drivers/scsi/cxlflash/ocxl_hw.c | 22 ++++++++++++++++++++++
 4 files changed, 25 insertions(+), 2 deletions(-)
 create mode 100644 drivers/scsi/cxlflash/ocxl_hw.c

diff --git a/drivers/scsi/cxlflash/Kconfig b/drivers/scsi/cxlflash/Kconfig
index a011c5d..e2a3a1b 100644
--- a/drivers/scsi/cxlflash/Kconfig
+++ b/drivers/scsi/cxlflash/Kconfig
@@ -4,7 +4,7 @@
 
 config CXLFLASH
 	tristate "Support for IBM CAPI Flash"
-	depends on PCI && SCSI && CXL && EEH
+	depends on PCI && SCSI && CXL && OCXL && EEH
 	select IRQ_POLL
 	default m
 	help
diff --git a/drivers/scsi/cxlflash/Makefile b/drivers/scsi/cxlflash/Makefile
index 7ec3f6b..5124c68 100644
--- a/drivers/scsi/cxlflash/Makefile
+++ b/drivers/scsi/cxlflash/Makefile
@@ -1,2 +1,2 @@
 obj-$(CONFIG_CXLFLASH) += cxlflash.o
-cxlflash-y += main.o superpipe.o lunmgt.o vlun.o cxl_hw.o
+cxlflash-y += main.o superpipe.o lunmgt.o vlun.o cxl_hw.o ocxl_hw.o
diff --git a/drivers/scsi/cxlflash/backend.h b/drivers/scsi/cxlflash/backend.h
index 7b72149..a60f051 100644
--- a/drivers/scsi/cxlflash/backend.h
+++ b/drivers/scsi/cxlflash/backend.h
@@ -13,6 +13,7 @@
  */
 
 extern const struct cxlflash_backend_ops cxlflash_cxl_ops;
+extern const struct cxlflash_backend_ops cxlflash_ocxl_ops;
 
 struct cxlflash_backend_ops {
 	struct module *module;
diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
new file mode 100644
index 0000000..58a3182
--- /dev/null
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -0,0 +1,22 @@
+/*
+ * CXL Flash Device Driver
+ *
+ * Written by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>, IBM Corporation
+ *             Uma Krishnan <ukrishn@linux.vnet.ibm.com>, IBM Corporation
+ *
+ * Copyright (C) 2018 IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <misc/ocxl.h>
+
+#include "backend.h"
+
+/* Backend ops to ocxlflash services */
+const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
+	.module			= THIS_MODULE,
+};
-- 
2.1.0

[PATCH v3 04/41] cxlflash: Introduce OCXL backend

[Uma Krishnan]

Add initial infrastructure to support a new cxlflash transport, OCXL.

Claim a dependency on OCXL and add a new file, ocxl_hw.c, which will host
the backend routines that are specific to OCXL.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
---
 drivers/scsi/cxlflash/Kconfig   |  2 +-
 drivers/scsi/cxlflash/Makefile  |  2 +-
 drivers/scsi/cxlflash/backend.h |  1 +
 drivers/scsi/cxlflash/ocxl_hw.c | 22 ++++++++++++++++++++++
 4 files changed, 25 insertions(+), 2 deletions(-)
 create mode 100644 drivers/scsi/cxlflash/ocxl_hw.c

diff --git a/drivers/scsi/cxlflash/Kconfig b/drivers/scsi/cxlflash/Kconfig
index a011c5d..e2a3a1b 100644
--- a/drivers/scsi/cxlflash/Kconfig
+++ b/drivers/scsi/cxlflash/Kconfig
@@ -4,7 +4,7 @@
 
 config CXLFLASH
 	tristate "Support for IBM CAPI Flash"
-	depends on PCI && SCSI && CXL && EEH
+	depends on PCI && SCSI && CXL && OCXL && EEH
 	select IRQ_POLL
 	default m
 	help
diff --git a/drivers/scsi/cxlflash/Makefile b/drivers/scsi/cxlflash/Makefile
index 7ec3f6b..5124c68 100644
--- a/drivers/scsi/cxlflash/Makefile
+++ b/drivers/scsi/cxlflash/Makefile
@@ -1,2 +1,2 @@
 obj-$(CONFIG_CXLFLASH) += cxlflash.o
-cxlflash-y += main.o superpipe.o lunmgt.o vlun.o cxl_hw.o
+cxlflash-y += main.o superpipe.o lunmgt.o vlun.o cxl_hw.o ocxl_hw.o
diff --git a/drivers/scsi/cxlflash/backend.h b/drivers/scsi/cxlflash/backend.h
index 7b72149..a60f051 100644
--- a/drivers/scsi/cxlflash/backend.h
+++ b/drivers/scsi/cxlflash/backend.h
@@ -13,6 +13,7 @@
  */
 
 extern const struct cxlflash_backend_ops cxlflash_cxl_ops;
+extern const struct cxlflash_backend_ops cxlflash_ocxl_ops;
 
 struct cxlflash_backend_ops {
 	struct module *module;
diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
new file mode 100644
index 0000000..58a3182
--- /dev/null
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -0,0 +1,22 @@
+/*
+ * CXL Flash Device Driver
+ *
+ * Written by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>, IBM Corporation
+ *             Uma Krishnan <ukrishn@linux.vnet.ibm.com>, IBM Corporation
+ *
+ * Copyright (C) 2018 IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <misc/ocxl.h>
+
+#include "backend.h"
+
+/* Backend ops to ocxlflash services */
+const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
+	.module			= THIS_MODULE,
+};
-- 
2.1.0

[PATCH v3 05/41] cxlflash: Hardware AFU for OCXL

[Uma Krishnan]

When an adapter is initialized, transport specific configuration and MMIO
mapping details need to be saved. For CXL, this data is managed by the
underlying kernel module. To maintain a separation between the cxlflash
core and underlying transports, introduce a new structure to store data
specific to the OCXL AFU.

Initially only the pointers to underlying PCI and generic devices are
added to this new structure - it will be expanded further in future
commits. Services to create and destroy this hardware AFU are added and
integrated in the probe and exit paths of the driver.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
---
 drivers/scsi/cxlflash/backend.h |  1 +
 drivers/scsi/cxlflash/cxl_hw.c  |  6 ++++++
 drivers/scsi/cxlflash/main.c    |  9 +++++++--
 drivers/scsi/cxlflash/ocxl_hw.c | 40 ++++++++++++++++++++++++++++++++++++++++
 drivers/scsi/cxlflash/ocxl_hw.h | 19 +++++++++++++++++++
 5 files changed, 73 insertions(+), 2 deletions(-)
 create mode 100644 drivers/scsi/cxlflash/ocxl_hw.h

diff --git a/drivers/scsi/cxlflash/backend.h b/drivers/scsi/cxlflash/backend.h
index a60f051..f675bcb 100644
--- a/drivers/scsi/cxlflash/backend.h
+++ b/drivers/scsi/cxlflash/backend.h
@@ -36,6 +36,7 @@ struct cxlflash_backend_ops {
 	int (*allocate_afu_irqs)(void *ctx_cookie, int num);
 	void (*free_afu_irqs)(void *ctx_cookie);
 	void * (*create_afu)(struct pci_dev *dev);
+	void (*destroy_afu)(void *afu_cookie);
 	struct file * (*get_fd)(void *ctx_cookie, struct file_operations *fops,
 				int *fd);
 	void * (*fops_get_context)(struct file *file);
diff --git a/drivers/scsi/cxlflash/cxl_hw.c b/drivers/scsi/cxlflash/cxl_hw.c
index db1cada..a1d6d12 100644
--- a/drivers/scsi/cxlflash/cxl_hw.c
+++ b/drivers/scsi/cxlflash/cxl_hw.c
@@ -110,6 +110,11 @@ static void *cxlflash_create_afu(struct pci_dev *dev)
 	return cxl_pci_to_afu(dev);
 }
 
+static void cxlflash_destroy_afu(void *afu)
+{
+	/* Dummy fop for cxl */
+}
+
 static struct file *cxlflash_get_fd(void *ctx_cookie,
 				    struct file_operations *fops, int *fd)
 {
@@ -160,6 +165,7 @@ const struct cxlflash_backend_ops cxlflash_cxl_ops = {
 	.allocate_afu_irqs	= cxlflash_allocate_afu_irqs,
 	.free_afu_irqs		= cxlflash_free_afu_irqs,
 	.create_afu		= cxlflash_create_afu,
+	.destroy_afu		= cxlflash_destroy_afu,
 	.get_fd			= cxlflash_get_fd,
 	.fops_get_context	= cxlflash_fops_get_context,
 	.start_work		= cxlflash_start_work,
diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c
index b83a55a..5d754d1 100644
--- a/drivers/scsi/cxlflash/main.c
+++ b/drivers/scsi/cxlflash/main.c
@@ -971,6 +971,7 @@ static void cxlflash_remove(struct pci_dev *pdev)
 	case INIT_STATE_AFU:
 		term_afu(cfg);
 	case INIT_STATE_PCI:
+		cfg->ops->destroy_afu(cfg->afu_cookie);
 		pci_disable_device(pdev);
 	case INIT_STATE_NONE:
 		free_mem(cfg);
@@ -3689,8 +3690,6 @@ static int cxlflash_probe(struct pci_dev *pdev,
 
 	pci_set_drvdata(pdev, cfg);
 
-	cfg->afu_cookie = cfg->ops->create_afu(pdev);
-
 	rc = init_pci(cfg);
 	if (rc) {
 		dev_err(dev, "%s: init_pci failed rc=%d\n", __func__, rc);
@@ -3698,6 +3697,12 @@ static int cxlflash_probe(struct pci_dev *pdev,
 	}
 	cfg->init_state = INIT_STATE_PCI;
 
+	cfg->afu_cookie = cfg->ops->create_afu(pdev);
+	if (unlikely(!cfg->afu_cookie)) {
+		dev_err(dev, "%s: create_afu failed\n", __func__);
+		goto out_remove;
+	}
+
 	rc = init_afu(cfg);
 	if (rc && !wq_has_sleeper(&cfg->reset_waitq)) {
 		dev_err(dev, "%s: init_afu failed rc=%d\n", __func__, rc);
diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 58a3182..e3a0a9b 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -15,8 +15,48 @@
 #include <misc/ocxl.h>
 
 #include "backend.h"
+#include "ocxl_hw.h"
+
+/**
+ * ocxlflash_destroy_afu() - destroy the AFU structure
+ * @afu_cookie:	AFU to be freed.
+ */
+static void ocxlflash_destroy_afu(void *afu_cookie)
+{
+	struct ocxl_hw_afu *afu = afu_cookie;
+
+	if (!afu)
+		return;
+
+	kfree(afu);
+}
+
+/**
+ * ocxlflash_create_afu() - create the AFU for OCXL
+ * @pdev:	PCI device associated with the host.
+ *
+ * Return: AFU on success, NULL on failure
+ */
+static void *ocxlflash_create_afu(struct pci_dev *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct ocxl_hw_afu *afu;
+
+	afu = kzalloc(sizeof(*afu), GFP_KERNEL);
+	if (unlikely(!afu)) {
+		dev_err(dev, "%s: HW AFU allocation failed\n", __func__);
+		goto out;
+	}
+
+	afu->pdev = pdev;
+	afu->dev = dev;
+out:
+	return afu;
+}
 
 /* Backend ops to ocxlflash services */
 const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.module			= THIS_MODULE,
+	.create_afu		= ocxlflash_create_afu,
+	.destroy_afu		= ocxlflash_destroy_afu,
 };
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
new file mode 100644
index 0000000..c7e5c4d
--- /dev/null
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -0,0 +1,19 @@
+/*
+ * CXL Flash Device Driver
+ *
+ * Written by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>, IBM Corporation
+ *	       Uma Krishnan <ukrishn@linux.vnet.ibm.com>, IBM Corporation
+ *
+ * Copyright (C) 2018 IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+/* OCXL hardware AFU associated with the host */
+struct ocxl_hw_afu {
+	struct pci_dev *pdev;		/* PCI device */
+	struct device *dev;		/* Generic device */
+};
-- 
2.1.0

[PATCH v3 05/41] cxlflash: Hardware AFU for OCXL

[Uma Krishnan]

When an adapter is initialized, transport specific configuration and MMIO
mapping details need to be saved. For CXL, this data is managed by the
underlying kernel module. To maintain a separation between the cxlflash
core and underlying transports, introduce a new structure to store data
specific to the OCXL AFU.

Initially only the pointers to underlying PCI and generic devices are
added to this new structure - it will be expanded further in future
commits. Services to create and destroy this hardware AFU are added and
integrated in the probe and exit paths of the driver.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
---
 drivers/scsi/cxlflash/backend.h |  1 +
 drivers/scsi/cxlflash/cxl_hw.c  |  6 ++++++
 drivers/scsi/cxlflash/main.c    |  9 +++++++--
 drivers/scsi/cxlflash/ocxl_hw.c | 40 ++++++++++++++++++++++++++++++++++++++++
 drivers/scsi/cxlflash/ocxl_hw.h | 19 +++++++++++++++++++
 5 files changed, 73 insertions(+), 2 deletions(-)
 create mode 100644 drivers/scsi/cxlflash/ocxl_hw.h

diff --git a/drivers/scsi/cxlflash/backend.h b/drivers/scsi/cxlflash/backend.h
index a60f051..f675bcb 100644
--- a/drivers/scsi/cxlflash/backend.h
+++ b/drivers/scsi/cxlflash/backend.h
@@ -36,6 +36,7 @@ struct cxlflash_backend_ops {
 	int (*allocate_afu_irqs)(void *ctx_cookie, int num);
 	void (*free_afu_irqs)(void *ctx_cookie);
 	void * (*create_afu)(struct pci_dev *dev);
+	void (*destroy_afu)(void *afu_cookie);
 	struct file * (*get_fd)(void *ctx_cookie, struct file_operations *fops,
 				int *fd);
 	void * (*fops_get_context)(struct file *file);
diff --git a/drivers/scsi/cxlflash/cxl_hw.c b/drivers/scsi/cxlflash/cxl_hw.c
index db1cada..a1d6d12 100644
--- a/drivers/scsi/cxlflash/cxl_hw.c
+++ b/drivers/scsi/cxlflash/cxl_hw.c
@@ -110,6 +110,11 @@ static void *cxlflash_create_afu(struct pci_dev *dev)
 	return cxl_pci_to_afu(dev);
 }
 
+static void cxlflash_destroy_afu(void *afu)
+{
+	/* Dummy fop for cxl */
+}
+
 static struct file *cxlflash_get_fd(void *ctx_cookie,
 				    struct file_operations *fops, int *fd)
 {
@@ -160,6 +165,7 @@ const struct cxlflash_backend_ops cxlflash_cxl_ops = {
 	.allocate_afu_irqs	= cxlflash_allocate_afu_irqs,
 	.free_afu_irqs		= cxlflash_free_afu_irqs,
 	.create_afu		= cxlflash_create_afu,
+	.destroy_afu		= cxlflash_destroy_afu,
 	.get_fd			= cxlflash_get_fd,
 	.fops_get_context	= cxlflash_fops_get_context,
 	.start_work		= cxlflash_start_work,
diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c
index b83a55a..5d754d1 100644
--- a/drivers/scsi/cxlflash/main.c
+++ b/drivers/scsi/cxlflash/main.c
@@ -971,6 +971,7 @@ static void cxlflash_remove(struct pci_dev *pdev)
 	case INIT_STATE_AFU:
 		term_afu(cfg);
 	case INIT_STATE_PCI:
+		cfg->ops->destroy_afu(cfg->afu_cookie);
 		pci_disable_device(pdev);
 	case INIT_STATE_NONE:
 		free_mem(cfg);
@@ -3689,8 +3690,6 @@ static int cxlflash_probe(struct pci_dev *pdev,
 
 	pci_set_drvdata(pdev, cfg);
 
-	cfg->afu_cookie = cfg->ops->create_afu(pdev);
-
 	rc = init_pci(cfg);
 	if (rc) {
 		dev_err(dev, "%s: init_pci failed rc=%d\n", __func__, rc);
@@ -3698,6 +3697,12 @@ static int cxlflash_probe(struct pci_dev *pdev,
 	}
 	cfg->init_state = INIT_STATE_PCI;
 
+	cfg->afu_cookie = cfg->ops->create_afu(pdev);
+	if (unlikely(!cfg->afu_cookie)) {
+		dev_err(dev, "%s: create_afu failed\n", __func__);
+		goto out_remove;
+	}
+
 	rc = init_afu(cfg);
 	if (rc && !wq_has_sleeper(&cfg->reset_waitq)) {
 		dev_err(dev, "%s: init_afu failed rc=%d\n", __func__, rc);
diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 58a3182..e3a0a9b 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -15,8 +15,48 @@
 #include <misc/ocxl.h>
 
 #include "backend.h"
+#include "ocxl_hw.h"
+
+/**
+ * ocxlflash_destroy_afu() - destroy the AFU structure
+ * @afu_cookie:	AFU to be freed.
+ */
+static void ocxlflash_destroy_afu(void *afu_cookie)
+{
+	struct ocxl_hw_afu *afu = afu_cookie;
+
+	if (!afu)
+		return;
+
+	kfree(afu);
+}
+
+/**
+ * ocxlflash_create_afu() - create the AFU for OCXL
+ * @pdev:	PCI device associated with the host.
+ *
+ * Return: AFU on success, NULL on failure
+ */
+static void *ocxlflash_create_afu(struct pci_dev *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct ocxl_hw_afu *afu;
+
+	afu = kzalloc(sizeof(*afu), GFP_KERNEL);
+	if (unlikely(!afu)) {
+		dev_err(dev, "%s: HW AFU allocation failed\n", __func__);
+		goto out;
+	}
+
+	afu->pdev = pdev;
+	afu->dev = dev;
+out:
+	return afu;
+}
 
 /* Backend ops to ocxlflash services */
 const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.module			= THIS_MODULE,
+	.create_afu		= ocxlflash_create_afu,
+	.destroy_afu		= ocxlflash_destroy_afu,
 };
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
new file mode 100644
index 0000000..c7e5c4d
--- /dev/null
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -0,0 +1,19 @@
+/*
+ * CXL Flash Device Driver
+ *
+ * Written by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>, IBM Corporation
+ *	       Uma Krishnan <ukrishn@linux.vnet.ibm.com>, IBM Corporation
+ *
+ * Copyright (C) 2018 IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+/* OCXL hardware AFU associated with the host */
+struct ocxl_hw_afu {
+	struct pci_dev *pdev;		/* PCI device */
+	struct device *dev;		/* Generic device */
+};
-- 
2.1.0

[PATCH v3 06/41] cxlflash: Read host function configuration

[Uma Krishnan]

Per the OCXL specification, the underlying host can have multiple AFUs
per function with each function supporting its own configuration. The host
function configuration is read on the initialization path to evaluate the
number of functions present and identify the features and configuration of
the functions present. This data is cached for use in later configuration
steps. Note that for the OCXL hardware supported by the cxlflash driver,
only one AFU per function is expected.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 44 +++++++++++++++++++++++++++++++++++++++++
 drivers/scsi/cxlflash/ocxl_hw.h |  4 ++++
 2 files changed, 48 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index e3a0a9b..85c0f84 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -32,6 +32,38 @@ static void ocxlflash_destroy_afu(void *afu_cookie)
 }
 
 /**
+ * ocxlflash_config_fn() - configure the host function
+ * @pdev:	PCI device associated with the host.
+ * @afu:	AFU associated with the host.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_config_fn(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
+{
+	struct ocxl_fn_config *fcfg = &afu->fcfg;
+	struct device *dev = &pdev->dev;
+	int rc = 0;
+
+	/* Read DVSEC config of the function */
+	rc = ocxl_config_read_function(pdev, fcfg);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: ocxl_config_read_function failed rc=%d\n",
+			__func__, rc);
+		goto out;
+	}
+
+	/* Check if function has AFUs defined, only 1 per function supported */
+	if (fcfg->max_afu_index >= 0) {
+		afu->is_present = true;
+		if (fcfg->max_afu_index != 0)
+			dev_warn(dev, "%s: Unexpected AFU index value %d\n",
+				 __func__, fcfg->max_afu_index);
+	}
+out:
+	return rc;
+}
+
+/**
  * ocxlflash_create_afu() - create the AFU for OCXL
  * @pdev:	PCI device associated with the host.
  *
@@ -41,6 +73,7 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct ocxl_hw_afu *afu;
+	int rc;
 
 	afu = kzalloc(sizeof(*afu), GFP_KERNEL);
 	if (unlikely(!afu)) {
@@ -50,8 +83,19 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
 
 	afu->pdev = pdev;
 	afu->dev = dev;
+
+	rc = ocxlflash_config_fn(pdev, afu);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: Function configuration failed rc=%d\n",
+			__func__, rc);
+		goto err1;
+	}
 out:
 	return afu;
+err1:
+	kfree(afu);
+	afu = NULL;
+	goto out;
 }
 
 /* Backend ops to ocxlflash services */
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index c7e5c4d..356a6a3 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -16,4 +16,8 @@
 struct ocxl_hw_afu {
 	struct pci_dev *pdev;		/* PCI device */
 	struct device *dev;		/* Generic device */
+
+	struct ocxl_fn_config fcfg;	/* DVSEC config of the function */
+
+	bool is_present;		/* Function has AFUs defined */
 };
-- 
2.1.0

[PATCH v3 06/41] cxlflash: Read host function configuration

[Uma Krishnan]

Per the OCXL specification, the underlying host can have multiple AFUs
per function with each function supporting its own configuration. The host
function configuration is read on the initialization path to evaluate the
number of functions present and identify the features and configuration of
the functions present. This data is cached for use in later configuration
steps. Note that for the OCXL hardware supported by the cxlflash driver,
only one AFU per function is expected.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 44 +++++++++++++++++++++++++++++++++++++++++
 drivers/scsi/cxlflash/ocxl_hw.h |  4 ++++
 2 files changed, 48 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index e3a0a9b..85c0f84 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -32,6 +32,38 @@ static void ocxlflash_destroy_afu(void *afu_cookie)
 }
 
 /**
+ * ocxlflash_config_fn() - configure the host function
+ * @pdev:	PCI device associated with the host.
+ * @afu:	AFU associated with the host.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_config_fn(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
+{
+	struct ocxl_fn_config *fcfg = &afu->fcfg;
+	struct device *dev = &pdev->dev;
+	int rc = 0;
+
+	/* Read DVSEC config of the function */
+	rc = ocxl_config_read_function(pdev, fcfg);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: ocxl_config_read_function failed rc=%d\n",
+			__func__, rc);
+		goto out;
+	}
+
+	/* Check if function has AFUs defined, only 1 per function supported */
+	if (fcfg->max_afu_index >= 0) {
+		afu->is_present = true;
+		if (fcfg->max_afu_index != 0)
+			dev_warn(dev, "%s: Unexpected AFU index value %d\n",
+				 __func__, fcfg->max_afu_index);
+	}
+out:
+	return rc;
+}
+
+/**
  * ocxlflash_create_afu() - create the AFU for OCXL
  * @pdev:	PCI device associated with the host.
  *
@@ -41,6 +73,7 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct ocxl_hw_afu *afu;
+	int rc;
 
 	afu = kzalloc(sizeof(*afu), GFP_KERNEL);
 	if (unlikely(!afu)) {
@@ -50,8 +83,19 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
 
 	afu->pdev = pdev;
 	afu->dev = dev;
+
+	rc = ocxlflash_config_fn(pdev, afu);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: Function configuration failed rc=%d\n",
+			__func__, rc);
+		goto err1;
+	}
 out:
 	return afu;
+err1:
+	kfree(afu);
+	afu = NULL;
+	goto out;
 }
 
 /* Backend ops to ocxlflash services */
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index c7e5c4d..356a6a3 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -16,4 +16,8 @@
 struct ocxl_hw_afu {
 	struct pci_dev *pdev;		/* PCI device */
 	struct device *dev;		/* Generic device */
+
+	struct ocxl_fn_config fcfg;	/* DVSEC config of the function */
+
+	bool is_present;		/* Function has AFUs defined */
 };
-- 
2.1.0

[PATCH v3 07/41] cxlflash: Setup function acTag range

[Uma Krishnan]

The OCXL specification supports distributing acTags amongst different
AFUs and functions on the link. The platform-specific acTag range for the
link is obtained using the OCXL provider services and then assigned to the
host function based on implementation.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 15 +++++++++++++++
 drivers/scsi/cxlflash/ocxl_hw.h |  3 +++
 2 files changed, 18 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 85c0f84..7783842 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -42,6 +42,7 @@ static int ocxlflash_config_fn(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
 {
 	struct ocxl_fn_config *fcfg = &afu->fcfg;
 	struct device *dev = &pdev->dev;
+	u16 base, enabled, supported;
 	int rc = 0;
 
 	/* Read DVSEC config of the function */
@@ -59,6 +60,20 @@ static int ocxlflash_config_fn(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
 			dev_warn(dev, "%s: Unexpected AFU index value %d\n",
 				 __func__, fcfg->max_afu_index);
 	}
+
+	rc = ocxl_config_get_actag_info(pdev, &base, &enabled, &supported);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: ocxl_config_get_actag_info failed rc=%d\n",
+			__func__, rc);
+		goto out;
+	}
+
+	afu->fn_actag_base = base;
+	afu->fn_actag_enabled = enabled;
+
+	ocxl_config_set_actag(pdev, fcfg->dvsec_function_pos, base, enabled);
+	dev_dbg(dev, "%s: Function acTag range base=%u enabled=%u\n",
+		__func__, base, enabled);
 out:
 	return rc;
 }
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index 356a6a3..55e833cb 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -19,5 +19,8 @@ struct ocxl_hw_afu {
 
 	struct ocxl_fn_config fcfg;	/* DVSEC config of the function */
 
+	int fn_actag_base;		/* Function acTag base */
+	int fn_actag_enabled;		/* Function acTag number enabled */
+
 	bool is_present;		/* Function has AFUs defined */
 };
-- 
2.1.0

[PATCH v3 07/41] cxlflash: Setup function acTag range

[Uma Krishnan]

The OCXL specification supports distributing acTags amongst different
AFUs and functions on the link. The platform-specific acTag range for the
link is obtained using the OCXL provider services and then assigned to the
host function based on implementation.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 15 +++++++++++++++
 drivers/scsi/cxlflash/ocxl_hw.h |  3 +++
 2 files changed, 18 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 85c0f84..7783842 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -42,6 +42,7 @@ static int ocxlflash_config_fn(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
 {
 	struct ocxl_fn_config *fcfg = &afu->fcfg;
 	struct device *dev = &pdev->dev;
+	u16 base, enabled, supported;
 	int rc = 0;
 
 	/* Read DVSEC config of the function */
@@ -59,6 +60,20 @@ static int ocxlflash_config_fn(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
 			dev_warn(dev, "%s: Unexpected AFU index value %d\n",
 				 __func__, fcfg->max_afu_index);
 	}
+
+	rc = ocxl_config_get_actag_info(pdev, &base, &enabled, &supported);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: ocxl_config_get_actag_info failed rc=%d\n",
+			__func__, rc);
+		goto out;
+	}
+
+	afu->fn_actag_base = base;
+	afu->fn_actag_enabled = enabled;
+
+	ocxl_config_set_actag(pdev, fcfg->dvsec_function_pos, base, enabled);
+	dev_dbg(dev, "%s: Function acTag range base=%u enabled=%u\n",
+		__func__, base, enabled);
 out:
 	return rc;
 }
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index 356a6a3..55e833cb 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -19,5 +19,8 @@ struct ocxl_hw_afu {
 
 	struct ocxl_fn_config fcfg;	/* DVSEC config of the function */
 
+	int fn_actag_base;		/* Function acTag base */
+	int fn_actag_enabled;		/* Function acTag number enabled */
+
 	bool is_present;		/* Function has AFUs defined */
 };
-- 
2.1.0

[PATCH v3 08/41] cxlflash: Read host AFU configuration

[Uma Krishnan]

The host AFU configuration is read on the initialization path to identify
the features and configuration of the AFU. This data is cached for use in
later configuration steps.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 38 ++++++++++++++++++++++++++++++++++++++
 drivers/scsi/cxlflash/ocxl_hw.h |  1 +
 2 files changed, 39 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 7783842..11399cf 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -79,6 +79,37 @@ static int ocxlflash_config_fn(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
 }
 
 /**
+ * ocxlflash_config_afu() - configure the host AFU
+ * @pdev:	PCI device associated with the host.
+ * @afu:	AFU associated with the host.
+ *
+ * Must be called _after_ host function configuration.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_config_afu(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
+{
+	struct ocxl_afu_config *acfg = &afu->acfg;
+	struct ocxl_fn_config *fcfg = &afu->fcfg;
+	struct device *dev = &pdev->dev;
+	int rc = 0;
+
+	/* This HW AFU function does not have any AFUs defined */
+	if (!afu->is_present)
+		goto out;
+
+	/* Read AFU config at index 0 */
+	rc = ocxl_config_read_afu(pdev, fcfg, acfg, 0);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: ocxl_config_read_afu failed rc=%d\n",
+			__func__, rc);
+		goto out;
+	}
+out:
+	return rc;
+}
+
+/**
  * ocxlflash_create_afu() - create the AFU for OCXL
  * @pdev:	PCI device associated with the host.
  *
@@ -105,6 +136,13 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
 			__func__, rc);
 		goto err1;
 	}
+
+	rc = ocxlflash_config_afu(pdev, afu);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: AFU configuration failed rc=%d\n",
+			__func__, rc);
+		goto err1;
+	}
 out:
 	return afu;
 err1:
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index 55e833cb..c9b2843 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -18,6 +18,7 @@ struct ocxl_hw_afu {
 	struct device *dev;		/* Generic device */
 
 	struct ocxl_fn_config fcfg;	/* DVSEC config of the function */
+	struct ocxl_afu_config acfg;	/* AFU configuration data */
 
 	int fn_actag_base;		/* Function acTag base */
 	int fn_actag_enabled;		/* Function acTag number enabled */
-- 
2.1.0

[PATCH v3 08/41] cxlflash: Read host AFU configuration

[Uma Krishnan]

The host AFU configuration is read on the initialization path to identify
the features and configuration of the AFU. This data is cached for use in
later configuration steps.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 38 ++++++++++++++++++++++++++++++++++++++
 drivers/scsi/cxlflash/ocxl_hw.h |  1 +
 2 files changed, 39 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 7783842..11399cf 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -79,6 +79,37 @@ static int ocxlflash_config_fn(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
 }
 
 /**
+ * ocxlflash_config_afu() - configure the host AFU
+ * @pdev:	PCI device associated with the host.
+ * @afu:	AFU associated with the host.
+ *
+ * Must be called _after_ host function configuration.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_config_afu(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
+{
+	struct ocxl_afu_config *acfg = &afu->acfg;
+	struct ocxl_fn_config *fcfg = &afu->fcfg;
+	struct device *dev = &pdev->dev;
+	int rc = 0;
+
+	/* This HW AFU function does not have any AFUs defined */
+	if (!afu->is_present)
+		goto out;
+
+	/* Read AFU config at index 0 */
+	rc = ocxl_config_read_afu(pdev, fcfg, acfg, 0);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: ocxl_config_read_afu failed rc=%d\n",
+			__func__, rc);
+		goto out;
+	}
+out:
+	return rc;
+}
+
+/**
  * ocxlflash_create_afu() - create the AFU for OCXL
  * @pdev:	PCI device associated with the host.
  *
@@ -105,6 +136,13 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
 			__func__, rc);
 		goto err1;
 	}
+
+	rc = ocxlflash_config_afu(pdev, afu);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: AFU configuration failed rc=%d\n",
+			__func__, rc);
+		goto err1;
+	}
 out:
 	return afu;
 err1:
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index 55e833cb..c9b2843 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -18,6 +18,7 @@ struct ocxl_hw_afu {
 	struct device *dev;		/* Generic device */
 
 	struct ocxl_fn_config fcfg;	/* DVSEC config of the function */
+	struct ocxl_afu_config acfg;	/* AFU configuration data */
 
 	int fn_actag_base;		/* Function acTag base */
 	int fn_actag_enabled;		/* Function acTag number enabled */
-- 
2.1.0

[PATCH v3 09/41] cxlflash: Setup AFU acTag range

[Uma Krishnan]

The OCXL specification supports distributing acTags amongst different
AFUs and functions on the link. As cxlflash devices are expected to only
support a single AFU per function, the entire range that was assigned to
the function is also assigned to the AFU.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 13 +++++++++++++
 drivers/scsi/cxlflash/ocxl_hw.h |  2 ++
 2 files changed, 15 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 11399cf..105712b 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -92,6 +92,9 @@ static int ocxlflash_config_afu(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
 	struct ocxl_afu_config *acfg = &afu->acfg;
 	struct ocxl_fn_config *fcfg = &afu->fcfg;
 	struct device *dev = &pdev->dev;
+	int count;
+	int base;
+	int pos;
 	int rc = 0;
 
 	/* This HW AFU function does not have any AFUs defined */
@@ -105,6 +108,16 @@ static int ocxlflash_config_afu(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
 			__func__, rc);
 		goto out;
 	}
+
+	/* Only one AFU per function is supported, so actag_base is same */
+	base = afu->fn_actag_base;
+	count = min_t(int, acfg->actag_supported, afu->fn_actag_enabled);
+	pos = acfg->dvsec_afu_control_pos;
+
+	ocxl_config_set_afu_actag(pdev, pos, base, count);
+	dev_dbg(dev, "%s: acTag base=%d enabled=%d\n", __func__, base, count);
+	afu->afu_actag_base = base;
+	afu->afu_actag_enabled = count;
 out:
 	return rc;
 }
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index c9b2843..21803b5 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -22,6 +22,8 @@ struct ocxl_hw_afu {
 
 	int fn_actag_base;		/* Function acTag base */
 	int fn_actag_enabled;		/* Function acTag number enabled */
+	int afu_actag_base;		/* AFU acTag base */
+	int afu_actag_enabled;		/* AFU acTag number enabled */
 
 	bool is_present;		/* Function has AFUs defined */
 };
-- 
2.1.0

[PATCH v3 09/41] cxlflash: Setup AFU acTag range

[Uma Krishnan]

The OCXL specification supports distributing acTags amongst different
AFUs and functions on the link. As cxlflash devices are expected to only
support a single AFU per function, the entire range that was assigned to
the function is also assigned to the AFU.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 13 +++++++++++++
 drivers/scsi/cxlflash/ocxl_hw.h |  2 ++
 2 files changed, 15 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 11399cf..105712b 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -92,6 +92,9 @@ static int ocxlflash_config_afu(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
 	struct ocxl_afu_config *acfg = &afu->acfg;
 	struct ocxl_fn_config *fcfg = &afu->fcfg;
 	struct device *dev = &pdev->dev;
+	int count;
+	int base;
+	int pos;
 	int rc = 0;
 
 	/* This HW AFU function does not have any AFUs defined */
@@ -105,6 +108,16 @@ static int ocxlflash_config_afu(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
 			__func__, rc);
 		goto out;
 	}
+
+	/* Only one AFU per function is supported, so actag_base is same */
+	base = afu->fn_actag_base;
+	count = min_t(int, acfg->actag_supported, afu->fn_actag_enabled);
+	pos = acfg->dvsec_afu_control_pos;
+
+	ocxl_config_set_afu_actag(pdev, pos, base, count);
+	dev_dbg(dev, "%s: acTag base=%d enabled=%d\n", __func__, base, count);
+	afu->afu_actag_base = base;
+	afu->afu_actag_enabled = count;
 out:
 	return rc;
 }
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index c9b2843..21803b5 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -22,6 +22,8 @@ struct ocxl_hw_afu {
 
 	int fn_actag_base;		/* Function acTag base */
 	int fn_actag_enabled;		/* Function acTag number enabled */
+	int afu_actag_base;		/* AFU acTag base */
+	int afu_actag_enabled;		/* AFU acTag number enabled */
 
 	bool is_present;		/* Function has AFUs defined */
 };
-- 
2.1.0

[PATCH v3 10/41] cxlflash: Setup AFU PASID

[Uma Krishnan]

Per the OCXL specification, the maximum PASID supported by the AFU is
indicated by a field within the configuration space. Similar to acTags,
implementations can choose to use any sub-range of PASID within their
assigned range. For cxlflash, the entire range is used.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 3 +++
 drivers/scsi/cxlflash/ocxl_hw.h | 1 +
 2 files changed, 4 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 105712b..44688af 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -118,6 +118,9 @@ static int ocxlflash_config_afu(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
 	dev_dbg(dev, "%s: acTag base=%d enabled=%d\n", __func__, base, count);
 	afu->afu_actag_base = base;
 	afu->afu_actag_enabled = count;
+	afu->max_pasid = 1 << acfg->pasid_supported_log;
+
+	ocxl_config_set_afu_pasid(pdev, pos, 0, acfg->pasid_supported_log);
 out:
 	return rc;
 }
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index 21803b5..46de75b 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -25,5 +25,6 @@ struct ocxl_hw_afu {
 	int afu_actag_base;		/* AFU acTag base */
 	int afu_actag_enabled;		/* AFU acTag number enabled */
 
+	int max_pasid;			/* Maximum number of contexts */
 	bool is_present;		/* Function has AFUs defined */
 };
-- 
2.1.0

[PATCH v3 10/41] cxlflash: Setup AFU PASID

[Uma Krishnan]

Per the OCXL specification, the maximum PASID supported by the AFU is
indicated by a field within the configuration space. Similar to acTags,
implementations can choose to use any sub-range of PASID within their
assigned range. For cxlflash, the entire range is used.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 3 +++
 drivers/scsi/cxlflash/ocxl_hw.h | 1 +
 2 files changed, 4 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 105712b..44688af 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -118,6 +118,9 @@ static int ocxlflash_config_afu(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
 	dev_dbg(dev, "%s: acTag base=%d enabled=%d\n", __func__, base, count);
 	afu->afu_actag_base = base;
 	afu->afu_actag_enabled = count;
+	afu->max_pasid = 1 << acfg->pasid_supported_log;
+
+	ocxl_config_set_afu_pasid(pdev, pos, 0, acfg->pasid_supported_log);
 out:
 	return rc;
 }
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index 21803b5..46de75b 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -25,5 +25,6 @@ struct ocxl_hw_afu {
 	int afu_actag_base;		/* AFU acTag base */
 	int afu_actag_enabled;		/* AFU acTag number enabled */
 
+	int max_pasid;			/* Maximum number of contexts */
 	bool is_present;		/* Function has AFUs defined */
 };
-- 
2.1.0

[PATCH v3 11/41] cxlflash: Adapter context support for OCXL

[Uma Krishnan]

Add support to create and release the adapter contexts for OCXL and
provide means to specify certain contexts as a master.

The existing cxlflash core has a design requirement that each host will
have a single host context available by default. To satisfy this
requirement, one host adapter context is created when the hardware AFU is
initialized. This is returned by the get_context() fop.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 90 +++++++++++++++++++++++++++++++++++++++++
 drivers/scsi/cxlflash/ocxl_hw.h |  6 +++
 2 files changed, 96 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 44688af..cbe4d93 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -18,6 +18,80 @@
 #include "ocxl_hw.h"
 
 /**
+ * ocxlflash_set_master() - sets the context as master
+ * @ctx_cookie:	Adapter context to set as master.
+ */
+static void ocxlflash_set_master(void *ctx_cookie)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+
+	ctx->master = true;
+}
+
+/**
+ * ocxlflash_get_context() - obtains the context associated with the host
+ * @pdev:	PCI device associated with the host.
+ * @afu_cookie:	Hardware AFU associated with the host.
+ *
+ * Return: returns the pointer to host adapter context
+ */
+static void *ocxlflash_get_context(struct pci_dev *pdev, void *afu_cookie)
+{
+	struct ocxl_hw_afu *afu = afu_cookie;
+
+	return afu->ocxl_ctx;
+}
+
+/**
+ * ocxlflash_dev_context_init() - allocate and initialize an adapter context
+ * @pdev:	PCI device associated with the host.
+ * @afu_cookie:	Hardware AFU associated with the host.
+ *
+ * Return: returns the adapter context on success, ERR_PTR on failure
+ */
+static void *ocxlflash_dev_context_init(struct pci_dev *pdev, void *afu_cookie)
+{
+	struct ocxl_hw_afu *afu = afu_cookie;
+	struct device *dev = afu->dev;
+	struct ocxlflash_context *ctx;
+	int rc;
+
+	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+	if (unlikely(!ctx)) {
+		dev_err(dev, "%s: Context allocation failed\n", __func__);
+		rc = -ENOMEM;
+		goto err;
+	}
+
+	ctx->master = false;
+	ctx->hw_afu = afu;
+out:
+	return ctx;
+err:
+	ctx = ERR_PTR(rc);
+	goto out;
+}
+
+/**
+ * ocxlflash_release_context() - releases an adapter context
+ * @ctx_cookie:	Adapter context to be released.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_release_context(void *ctx_cookie)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+	int rc = 0;
+
+	if (!ctx)
+		goto out;
+
+	kfree(ctx);
+out:
+	return rc;
+}
+
+/**
  * ocxlflash_destroy_afu() - destroy the AFU structure
  * @afu_cookie:	AFU to be freed.
  */
@@ -28,6 +102,7 @@ static void ocxlflash_destroy_afu(void *afu_cookie)
 	if (!afu)
 		return;
 
+	ocxlflash_release_context(afu->ocxl_ctx);
 	kfree(afu);
 }
 
@@ -134,6 +209,7 @@ static int ocxlflash_config_afu(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
 static void *ocxlflash_create_afu(struct pci_dev *pdev)
 {
 	struct device *dev = &pdev->dev;
+	struct ocxlflash_context *ctx;
 	struct ocxl_hw_afu *afu;
 	int rc;
 
@@ -159,6 +235,16 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
 			__func__, rc);
 		goto err1;
 	}
+
+	ctx = ocxlflash_dev_context_init(pdev, afu);
+	if (IS_ERR(ctx)) {
+		rc = PTR_ERR(ctx);
+		dev_err(dev, "%s: ocxlflash_dev_context_init failed rc=%d\n",
+			__func__, rc);
+		goto err1;
+	}
+
+	afu->ocxl_ctx = ctx;
 out:
 	return afu;
 err1:
@@ -170,6 +256,10 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
 /* Backend ops to ocxlflash services */
 const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.module			= THIS_MODULE,
+	.set_master		= ocxlflash_set_master,
+	.get_context		= ocxlflash_get_context,
+	.dev_context_init	= ocxlflash_dev_context_init,
+	.release_context	= ocxlflash_release_context,
 	.create_afu		= ocxlflash_create_afu,
 	.destroy_afu		= ocxlflash_destroy_afu,
 };
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index 46de75b..f41ba0b 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -14,6 +14,7 @@
 
 /* OCXL hardware AFU associated with the host */
 struct ocxl_hw_afu {
+	struct ocxlflash_context *ocxl_ctx; /* Host context */
 	struct pci_dev *pdev;		/* PCI device */
 	struct device *dev;		/* Generic device */
 
@@ -28,3 +29,8 @@ struct ocxl_hw_afu {
 	int max_pasid;			/* Maximum number of contexts */
 	bool is_present;		/* Function has AFUs defined */
 };
+
+struct ocxlflash_context {
+	struct ocxl_hw_afu *hw_afu;	/* HW AFU back pointer */
+	bool master;			/* Whether this is a master context */
+};
-- 
2.1.0

[PATCH v3 11/41] cxlflash: Adapter context support for OCXL

[Uma Krishnan]

Add support to create and release the adapter contexts for OCXL and
provide means to specify certain contexts as a master.

The existing cxlflash core has a design requirement that each host will
have a single host context available by default. To satisfy this
requirement, one host adapter context is created when the hardware AFU is
initialized. This is returned by the get_context() fop.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 90 +++++++++++++++++++++++++++++++++++++++++
 drivers/scsi/cxlflash/ocxl_hw.h |  6 +++
 2 files changed, 96 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 44688af..cbe4d93 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -18,6 +18,80 @@
 #include "ocxl_hw.h"
 
 /**
+ * ocxlflash_set_master() - sets the context as master
+ * @ctx_cookie:	Adapter context to set as master.
+ */
+static void ocxlflash_set_master(void *ctx_cookie)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+
+	ctx->master = true;
+}
+
+/**
+ * ocxlflash_get_context() - obtains the context associated with the host
+ * @pdev:	PCI device associated with the host.
+ * @afu_cookie:	Hardware AFU associated with the host.
+ *
+ * Return: returns the pointer to host adapter context
+ */
+static void *ocxlflash_get_context(struct pci_dev *pdev, void *afu_cookie)
+{
+	struct ocxl_hw_afu *afu = afu_cookie;
+
+	return afu->ocxl_ctx;
+}
+
+/**
+ * ocxlflash_dev_context_init() - allocate and initialize an adapter context
+ * @pdev:	PCI device associated with the host.
+ * @afu_cookie:	Hardware AFU associated with the host.
+ *
+ * Return: returns the adapter context on success, ERR_PTR on failure
+ */
+static void *ocxlflash_dev_context_init(struct pci_dev *pdev, void *afu_cookie)
+{
+	struct ocxl_hw_afu *afu = afu_cookie;
+	struct device *dev = afu->dev;
+	struct ocxlflash_context *ctx;
+	int rc;
+
+	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+	if (unlikely(!ctx)) {
+		dev_err(dev, "%s: Context allocation failed\n", __func__);
+		rc = -ENOMEM;
+		goto err;
+	}
+
+	ctx->master = false;
+	ctx->hw_afu = afu;
+out:
+	return ctx;
+err:
+	ctx = ERR_PTR(rc);
+	goto out;
+}
+
+/**
+ * ocxlflash_release_context() - releases an adapter context
+ * @ctx_cookie:	Adapter context to be released.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_release_context(void *ctx_cookie)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+	int rc = 0;
+
+	if (!ctx)
+		goto out;
+
+	kfree(ctx);
+out:
+	return rc;
+}
+
+/**
  * ocxlflash_destroy_afu() - destroy the AFU structure
  * @afu_cookie:	AFU to be freed.
  */
@@ -28,6 +102,7 @@ static void ocxlflash_destroy_afu(void *afu_cookie)
 	if (!afu)
 		return;
 
+	ocxlflash_release_context(afu->ocxl_ctx);
 	kfree(afu);
 }
 
@@ -134,6 +209,7 @@ static int ocxlflash_config_afu(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
 static void *ocxlflash_create_afu(struct pci_dev *pdev)
 {
 	struct device *dev = &pdev->dev;
+	struct ocxlflash_context *ctx;
 	struct ocxl_hw_afu *afu;
 	int rc;
 
@@ -159,6 +235,16 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
 			__func__, rc);
 		goto err1;
 	}
+
+	ctx = ocxlflash_dev_context_init(pdev, afu);
+	if (IS_ERR(ctx)) {
+		rc = PTR_ERR(ctx);
+		dev_err(dev, "%s: ocxlflash_dev_context_init failed rc=%d\n",
+			__func__, rc);
+		goto err1;
+	}
+
+	afu->ocxl_ctx = ctx;
 out:
 	return afu;
 err1:
@@ -170,6 +256,10 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
 /* Backend ops to ocxlflash services */
 const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.module			= THIS_MODULE,
+	.set_master		= ocxlflash_set_master,
+	.get_context		= ocxlflash_get_context,
+	.dev_context_init	= ocxlflash_dev_context_init,
+	.release_context	= ocxlflash_release_context,
 	.create_afu		= ocxlflash_create_afu,
 	.destroy_afu		= ocxlflash_destroy_afu,
 };
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index 46de75b..f41ba0b 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -14,6 +14,7 @@
 
 /* OCXL hardware AFU associated with the host */
 struct ocxl_hw_afu {
+	struct ocxlflash_context *ocxl_ctx; /* Host context */
 	struct pci_dev *pdev;		/* PCI device */
 	struct device *dev;		/* Generic device */
 
@@ -28,3 +29,8 @@ struct ocxl_hw_afu {
 	int max_pasid;			/* Maximum number of contexts */
 	bool is_present;		/* Function has AFUs defined */
 };
+
+struct ocxlflash_context {
+	struct ocxl_hw_afu *hw_afu;	/* HW AFU back pointer */
+	bool master;			/* Whether this is a master context */
+};
-- 
2.1.0

[PATCH v3 12/41] cxlflash: Use IDR to manage adapter contexts

[Uma Krishnan]

A range of PASIDs are used as identifiers for the adapter contexts. These
contexts may be destroyed and created randomly. Use an IDR to keep track
of contexts that are in use and assign a unique identifier to new ones.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 21 +++++++++++++++++++--
 drivers/scsi/cxlflash/ocxl_hw.h |  2 ++
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index cbe4d93..e8864a1 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -12,6 +12,8 @@
  * 2 of the License, or (at your option) any later version.
  */
 
+#include <linux/idr.h>
+
 #include <misc/ocxl.h>
 
 #include "backend.h"
@@ -60,14 +62,25 @@ static void *ocxlflash_dev_context_init(struct pci_dev *pdev, void *afu_cookie)
 	if (unlikely(!ctx)) {
 		dev_err(dev, "%s: Context allocation failed\n", __func__);
 		rc = -ENOMEM;
-		goto err;
+		goto err1;
+	}
+
+	idr_preload(GFP_KERNEL);
+	rc = idr_alloc(&afu->idr, ctx, 0, afu->max_pasid, GFP_NOWAIT);
+	idr_preload_end();
+	if (unlikely(rc < 0)) {
+		dev_err(dev, "%s: idr_alloc failed rc=%d\n", __func__, rc);
+		goto err2;
 	}
 
+	ctx->pe = rc;
 	ctx->master = false;
 	ctx->hw_afu = afu;
 out:
 	return ctx;
-err:
+err2:
+	kfree(ctx);
+err1:
 	ctx = ERR_PTR(rc);
 	goto out;
 }
@@ -86,6 +99,7 @@ static int ocxlflash_release_context(void *ctx_cookie)
 	if (!ctx)
 		goto out;
 
+	idr_remove(&ctx->hw_afu->idr, ctx->pe);
 	kfree(ctx);
 out:
 	return rc;
@@ -103,6 +117,7 @@ static void ocxlflash_destroy_afu(void *afu_cookie)
 		return;
 
 	ocxlflash_release_context(afu->ocxl_ctx);
+	idr_destroy(&afu->idr);
 	kfree(afu);
 }
 
@@ -221,6 +236,7 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
 
 	afu->pdev = pdev;
 	afu->dev = dev;
+	idr_init(&afu->idr);
 
 	rc = ocxlflash_config_fn(pdev, afu);
 	if (unlikely(rc)) {
@@ -248,6 +264,7 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
 out:
 	return afu;
 err1:
+	idr_destroy(&afu->idr);
 	kfree(afu);
 	afu = NULL;
 	goto out;
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index f41ba0b..a5337b6 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -26,6 +26,7 @@ struct ocxl_hw_afu {
 	int afu_actag_base;		/* AFU acTag base */
 	int afu_actag_enabled;		/* AFU acTag number enabled */
 
+	struct idr idr;			/* IDR to manage contexts */
 	int max_pasid;			/* Maximum number of contexts */
 	bool is_present;		/* Function has AFUs defined */
 };
@@ -33,4 +34,5 @@ struct ocxl_hw_afu {
 struct ocxlflash_context {
 	struct ocxl_hw_afu *hw_afu;	/* HW AFU back pointer */
 	bool master;			/* Whether this is a master context */
+	int pe;				/* Process element */
 };
-- 
2.1.0

[PATCH v3 12/41] cxlflash: Use IDR to manage adapter contexts

[Uma Krishnan]

A range of PASIDs are used as identifiers for the adapter contexts. These
contexts may be destroyed and created randomly. Use an IDR to keep track
of contexts that are in use and assign a unique identifier to new ones.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 21 +++++++++++++++++++--
 drivers/scsi/cxlflash/ocxl_hw.h |  2 ++
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index cbe4d93..e8864a1 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -12,6 +12,8 @@
  * 2 of the License, or (at your option) any later version.
  */
 
+#include <linux/idr.h>
+
 #include <misc/ocxl.h>
 
 #include "backend.h"
@@ -60,14 +62,25 @@ static void *ocxlflash_dev_context_init(struct pci_dev *pdev, void *afu_cookie)
 	if (unlikely(!ctx)) {
 		dev_err(dev, "%s: Context allocation failed\n", __func__);
 		rc = -ENOMEM;
-		goto err;
+		goto err1;
+	}
+
+	idr_preload(GFP_KERNEL);
+	rc = idr_alloc(&afu->idr, ctx, 0, afu->max_pasid, GFP_NOWAIT);
+	idr_preload_end();
+	if (unlikely(rc < 0)) {
+		dev_err(dev, "%s: idr_alloc failed rc=%d\n", __func__, rc);
+		goto err2;
 	}
 
+	ctx->pe = rc;
 	ctx->master = false;
 	ctx->hw_afu = afu;
 out:
 	return ctx;
-err:
+err2:
+	kfree(ctx);
+err1:
 	ctx = ERR_PTR(rc);
 	goto out;
 }
@@ -86,6 +99,7 @@ static int ocxlflash_release_context(void *ctx_cookie)
 	if (!ctx)
 		goto out;
 
+	idr_remove(&ctx->hw_afu->idr, ctx->pe);
 	kfree(ctx);
 out:
 	return rc;
@@ -103,6 +117,7 @@ static void ocxlflash_destroy_afu(void *afu_cookie)
 		return;
 
 	ocxlflash_release_context(afu->ocxl_ctx);
+	idr_destroy(&afu->idr);
 	kfree(afu);
 }
 
@@ -221,6 +236,7 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
 
 	afu->pdev = pdev;
 	afu->dev = dev;
+	idr_init(&afu->idr);
 
 	rc = ocxlflash_config_fn(pdev, afu);
 	if (unlikely(rc)) {
@@ -248,6 +264,7 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
 out:
 	return afu;
 err1:
+	idr_destroy(&afu->idr);
 	kfree(afu);
 	afu = NULL;
 	goto out;
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index f41ba0b..a5337b6 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -26,6 +26,7 @@ struct ocxl_hw_afu {
 	int afu_actag_base;		/* AFU acTag base */
 	int afu_actag_enabled;		/* AFU acTag number enabled */
 
+	struct idr idr;			/* IDR to manage contexts */
 	int max_pasid;			/* Maximum number of contexts */
 	bool is_present;		/* Function has AFUs defined */
 };
@@ -33,4 +34,5 @@ struct ocxl_hw_afu {
 struct ocxlflash_context {
 	struct ocxl_hw_afu *hw_afu;	/* HW AFU back pointer */
 	bool master;			/* Whether this is a master context */
+	int pe;				/* Process element */
 };
-- 
2.1.0

[PATCH v3 13/41] cxlflash: Support adapter file descriptors for OCXL

[Uma Krishnan]

Allocate a file descriptor for an adapter context when requested. In order
to allocate inodes for the file descriptors, a pseudo filesystem is created
and used.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 200 ++++++++++++++++++++++++++++++++++++++++
 drivers/scsi/cxlflash/ocxl_hw.h |   1 +
 2 files changed, 201 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index e8864a1..49af059 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -12,13 +12,144 @@
  * 2 of the License, or (at your option) any later version.
  */
 
+#include <linux/file.h>
 #include <linux/idr.h>
+#include <linux/module.h>
+#include <linux/mount.h>
 
 #include <misc/ocxl.h>
 
 #include "backend.h"
 #include "ocxl_hw.h"
 
+/*
+ * Pseudo-filesystem to allocate inodes.
+ */
+
+#define OCXLFLASH_FS_MAGIC      0x1697698f
+
+static int ocxlflash_fs_cnt;
+static struct vfsmount *ocxlflash_vfs_mount;
+
+static const struct dentry_operations ocxlflash_fs_dops = {
+	.d_dname	= simple_dname,
+};
+
+/*
+ * ocxlflash_fs_mount() - mount the pseudo-filesystem
+ * @fs_type:	File system type.
+ * @flags:	Flags for the filesystem.
+ * @dev_name:	Device name associated with the filesystem.
+ * @data:	Data pointer.
+ *
+ * Return: pointer to the directory entry structure
+ */
+static struct dentry *ocxlflash_fs_mount(struct file_system_type *fs_type,
+					 int flags, const char *dev_name,
+					 void *data)
+{
+	return mount_pseudo(fs_type, "ocxlflash:", NULL, &ocxlflash_fs_dops,
+			    OCXLFLASH_FS_MAGIC);
+}
+
+static struct file_system_type ocxlflash_fs_type = {
+	.name		= "ocxlflash",
+	.owner		= THIS_MODULE,
+	.mount		= ocxlflash_fs_mount,
+	.kill_sb	= kill_anon_super,
+};
+
+/*
+ * ocxlflash_release_mapping() - release the memory mapping
+ * @ctx:	Context whose mapping is to be released.
+ */
+static void ocxlflash_release_mapping(struct ocxlflash_context *ctx)
+{
+	if (ctx->mapping)
+		simple_release_fs(&ocxlflash_vfs_mount, &ocxlflash_fs_cnt);
+	ctx->mapping = NULL;
+}
+
+/*
+ * ocxlflash_getfile() - allocate pseudo filesystem, inode, and the file
+ * @dev:	Generic device of the host.
+ * @name:	Name of the pseudo filesystem.
+ * @fops:	File operations.
+ * @priv:	Private data.
+ * @flags:	Flags for the file.
+ *
+ * Return: pointer to the file on success, ERR_PTR on failure
+ */
+static struct file *ocxlflash_getfile(struct device *dev, const char *name,
+				      const struct file_operations *fops,
+				      void *priv, int flags)
+{
+	struct qstr this;
+	struct path path;
+	struct file *file;
+	struct inode *inode = NULL;
+	int rc;
+
+	if (fops->owner && !try_module_get(fops->owner)) {
+		dev_err(dev, "%s: Owner does not exist\n", __func__);
+		rc = -ENOENT;
+		goto err1;
+	}
+
+	rc = simple_pin_fs(&ocxlflash_fs_type, &ocxlflash_vfs_mount,
+			   &ocxlflash_fs_cnt);
+	if (unlikely(rc < 0)) {
+		dev_err(dev, "%s: Cannot mount ocxlflash pseudofs rc=%d\n",
+			__func__, rc);
+		goto err2;
+	}
+
+	inode = alloc_anon_inode(ocxlflash_vfs_mount->mnt_sb);
+	if (IS_ERR(inode)) {
+		rc = PTR_ERR(inode);
+		dev_err(dev, "%s: alloc_anon_inode failed rc=%d\n",
+			__func__, rc);
+		goto err3;
+	}
+
+	this.name = name;
+	this.len = strlen(name);
+	this.hash = 0;
+	path.dentry = d_alloc_pseudo(ocxlflash_vfs_mount->mnt_sb, &this);
+	if (!path.dentry) {
+		dev_err(dev, "%s: d_alloc_pseudo failed\n", __func__);
+		rc = -ENOMEM;
+		goto err4;
+	}
+
+	path.mnt = mntget(ocxlflash_vfs_mount);
+	d_instantiate(path.dentry, inode);
+
+	file = alloc_file(&path, OPEN_FMODE(flags), fops);
+	if (IS_ERR(file)) {
+		rc = PTR_ERR(file);
+		dev_err(dev, "%s: alloc_file failed rc=%d\n",
+			__func__, rc);
+		goto err5;
+	}
+
+	file->f_flags = flags & (O_ACCMODE | O_NONBLOCK);
+	file->private_data = priv;
+out:
+	return file;
+err5:
+	path_put(&path);
+err4:
+	iput(inode);
+err3:
+	simple_release_fs(&ocxlflash_vfs_mount, &ocxlflash_fs_cnt);
+err2:
+	module_put(fops->owner);
+err1:
+	file = ERR_PTR(rc);
+	goto out;
+}
+
 /**
  * ocxlflash_set_master() - sets the context as master
  * @ctx_cookie:	Adapter context to set as master.
@@ -75,6 +206,7 @@ static void *ocxlflash_dev_context_init(struct pci_dev *pdev, void *afu_cookie)
 
 	ctx->pe = rc;
 	ctx->master = false;
+	ctx->mapping = NULL;
 	ctx->hw_afu = afu;
 out:
 	return ctx;
@@ -100,6 +232,7 @@ static int ocxlflash_release_context(void *ctx_cookie)
 		goto out;
 
 	idr_remove(&ctx->hw_afu->idr, ctx->pe);
+	ocxlflash_release_mapping(ctx);
 	kfree(ctx);
 out:
 	return rc;
@@ -270,6 +403,72 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
 	goto out;
 }
 
+static const struct file_operations ocxl_afu_fops = {
+	.owner		= THIS_MODULE,
+};
+
+/**
+ * ocxlflash_get_fd() - get file descriptor for an adapter context
+ * @ctx_cookie:	Adapter context.
+ * @fops:	File operations to be associated.
+ * @fd:		File descriptor to be returned back.
+ *
+ * Return: pointer to the file on success, ERR_PTR on failure
+ */
+static struct file *ocxlflash_get_fd(void *ctx_cookie,
+				     struct file_operations *fops, int *fd)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+	struct device *dev = ctx->hw_afu->dev;
+	struct file *file;
+	int flags, fdtmp;
+	int rc = 0;
+	char *name = NULL;
+
+	/* Only allow one fd per context */
+	if (ctx->mapping) {
+		dev_err(dev, "%s: Context is already mapped to an fd\n",
+			__func__);
+		rc = -EEXIST;
+		goto err1;
+	}
+
+	flags = O_RDWR | O_CLOEXEC;
+
+	/* This code is similar to anon_inode_getfd() */
+	rc = get_unused_fd_flags(flags);
+	if (unlikely(rc < 0)) {
+		dev_err(dev, "%s: get_unused_fd_flags failed rc=%d\n",
+			__func__, rc);
+		goto err1;
+	}
+	fdtmp = rc;
+
+	/* Use default ops if there is no fops */
+	if (!fops)
+		fops = (struct file_operations *)&ocxl_afu_fops;
+
+	name = kasprintf(GFP_KERNEL, "ocxlflash:%d", ctx->pe);
+	file = ocxlflash_getfile(dev, name, fops, ctx, flags);
+	kfree(name);
+	if (IS_ERR(file)) {
+		rc = PTR_ERR(file);
+		dev_err(dev, "%s: ocxlflash_getfile failed rc=%d\n",
+			__func__, rc);
+		goto err2;
+	}
+
+	ctx->mapping = file->f_mapping;
+	*fd = fdtmp;
+out:
+	return file;
+err2:
+	put_unused_fd(fdtmp);
+err1:
+	file = ERR_PTR(rc);
+	goto out;
+}
+
 /* Backend ops to ocxlflash services */
 const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.module			= THIS_MODULE,
@@ -279,4 +478,5 @@ const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.release_context	= ocxlflash_release_context,
 	.create_afu		= ocxlflash_create_afu,
 	.destroy_afu		= ocxlflash_destroy_afu,
+	.get_fd			= ocxlflash_get_fd,
 };
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index a5337b6..55db005 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -33,6 +33,7 @@ struct ocxl_hw_afu {
 
 struct ocxlflash_context {
 	struct ocxl_hw_afu *hw_afu;	/* HW AFU back pointer */
+	struct address_space *mapping;	/* Mapping for pseudo filesystem */
 	bool master;			/* Whether this is a master context */
 	int pe;				/* Process element */
 };
-- 
2.1.0

[PATCH v3 13/41] cxlflash: Support adapter file descriptors for OCXL

[Uma Krishnan]

Allocate a file descriptor for an adapter context when requested. In order
to allocate inodes for the file descriptors, a pseudo filesystem is created
and used.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 200 ++++++++++++++++++++++++++++++++++++++++
 drivers/scsi/cxlflash/ocxl_hw.h |   1 +
 2 files changed, 201 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index e8864a1..49af059 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -12,13 +12,144 @@
  * 2 of the License, or (at your option) any later version.
  */
 
+#include <linux/file.h>
 #include <linux/idr.h>
+#include <linux/module.h>
+#include <linux/mount.h>
 
 #include <misc/ocxl.h>
 
 #include "backend.h"
 #include "ocxl_hw.h"
 
+/*
+ * Pseudo-filesystem to allocate inodes.
+ */
+
+#define OCXLFLASH_FS_MAGIC      0x1697698f
+
+static int ocxlflash_fs_cnt;
+static struct vfsmount *ocxlflash_vfs_mount;
+
+static const struct dentry_operations ocxlflash_fs_dops = {
+	.d_dname	= simple_dname,
+};
+
+/*
+ * ocxlflash_fs_mount() - mount the pseudo-filesystem
+ * @fs_type:	File system type.
+ * @flags:	Flags for the filesystem.
+ * @dev_name:	Device name associated with the filesystem.
+ * @data:	Data pointer.
+ *
+ * Return: pointer to the directory entry structure
+ */
+static struct dentry *ocxlflash_fs_mount(struct file_system_type *fs_type,
+					 int flags, const char *dev_name,
+					 void *data)
+{
+	return mount_pseudo(fs_type, "ocxlflash:", NULL, &ocxlflash_fs_dops,
+			    OCXLFLASH_FS_MAGIC);
+}
+
+static struct file_system_type ocxlflash_fs_type = {
+	.name		= "ocxlflash",
+	.owner		= THIS_MODULE,
+	.mount		= ocxlflash_fs_mount,
+	.kill_sb	= kill_anon_super,
+};
+
+/*
+ * ocxlflash_release_mapping() - release the memory mapping
+ * @ctx:	Context whose mapping is to be released.
+ */
+static void ocxlflash_release_mapping(struct ocxlflash_context *ctx)
+{
+	if (ctx->mapping)
+		simple_release_fs(&ocxlflash_vfs_mount, &ocxlflash_fs_cnt);
+	ctx->mapping = NULL;
+}
+
+/*
+ * ocxlflash_getfile() - allocate pseudo filesystem, inode, and the file
+ * @dev:	Generic device of the host.
+ * @name:	Name of the pseudo filesystem.
+ * @fops:	File operations.
+ * @priv:	Private data.
+ * @flags:	Flags for the file.
+ *
+ * Return: pointer to the file on success, ERR_PTR on failure
+ */
+static struct file *ocxlflash_getfile(struct device *dev, const char *name,
+				      const struct file_operations *fops,
+				      void *priv, int flags)
+{
+	struct qstr this;
+	struct path path;
+	struct file *file;
+	struct inode *inode = NULL;
+	int rc;
+
+	if (fops->owner && !try_module_get(fops->owner)) {
+		dev_err(dev, "%s: Owner does not exist\n", __func__);
+		rc = -ENOENT;
+		goto err1;
+	}
+
+	rc = simple_pin_fs(&ocxlflash_fs_type, &ocxlflash_vfs_mount,
+			   &ocxlflash_fs_cnt);
+	if (unlikely(rc < 0)) {
+		dev_err(dev, "%s: Cannot mount ocxlflash pseudofs rc=%d\n",
+			__func__, rc);
+		goto err2;
+	}
+
+	inode = alloc_anon_inode(ocxlflash_vfs_mount->mnt_sb);
+	if (IS_ERR(inode)) {
+		rc = PTR_ERR(inode);
+		dev_err(dev, "%s: alloc_anon_inode failed rc=%d\n",
+			__func__, rc);
+		goto err3;
+	}
+
+	this.name = name;
+	this.len = strlen(name);
+	this.hash = 0;
+	path.dentry = d_alloc_pseudo(ocxlflash_vfs_mount->mnt_sb, &this);
+	if (!path.dentry) {
+		dev_err(dev, "%s: d_alloc_pseudo failed\n", __func__);
+		rc = -ENOMEM;
+		goto err4;
+	}
+
+	path.mnt = mntget(ocxlflash_vfs_mount);
+	d_instantiate(path.dentry, inode);
+
+	file = alloc_file(&path, OPEN_FMODE(flags), fops);
+	if (IS_ERR(file)) {
+		rc = PTR_ERR(file);
+		dev_err(dev, "%s: alloc_file failed rc=%d\n",
+			__func__, rc);
+		goto err5;
+	}
+
+	file->f_flags = flags & (O_ACCMODE | O_NONBLOCK);
+	file->private_data = priv;
+out:
+	return file;
+err5:
+	path_put(&path);
+err4:
+	iput(inode);
+err3:
+	simple_release_fs(&ocxlflash_vfs_mount, &ocxlflash_fs_cnt);
+err2:
+	module_put(fops->owner);
+err1:
+	file = ERR_PTR(rc);
+	goto out;
+}
+
 /**
  * ocxlflash_set_master() - sets the context as master
  * @ctx_cookie:	Adapter context to set as master.
@@ -75,6 +206,7 @@ static void *ocxlflash_dev_context_init(struct pci_dev *pdev, void *afu_cookie)
 
 	ctx->pe = rc;
 	ctx->master = false;
+	ctx->mapping = NULL;
 	ctx->hw_afu = afu;
 out:
 	return ctx;
@@ -100,6 +232,7 @@ static int ocxlflash_release_context(void *ctx_cookie)
 		goto out;
 
 	idr_remove(&ctx->hw_afu->idr, ctx->pe);
+	ocxlflash_release_mapping(ctx);
 	kfree(ctx);
 out:
 	return rc;
@@ -270,6 +403,72 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
 	goto out;
 }
 
+static const struct file_operations ocxl_afu_fops = {
+	.owner		= THIS_MODULE,
+};
+
+/**
+ * ocxlflash_get_fd() - get file descriptor for an adapter context
+ * @ctx_cookie:	Adapter context.
+ * @fops:	File operations to be associated.
+ * @fd:		File descriptor to be returned back.
+ *
+ * Return: pointer to the file on success, ERR_PTR on failure
+ */
+static struct file *ocxlflash_get_fd(void *ctx_cookie,
+				     struct file_operations *fops, int *fd)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+	struct device *dev = ctx->hw_afu->dev;
+	struct file *file;
+	int flags, fdtmp;
+	int rc = 0;
+	char *name = NULL;
+
+	/* Only allow one fd per context */
+	if (ctx->mapping) {
+		dev_err(dev, "%s: Context is already mapped to an fd\n",
+			__func__);
+		rc = -EEXIST;
+		goto err1;
+	}
+
+	flags = O_RDWR | O_CLOEXEC;
+
+	/* This code is similar to anon_inode_getfd() */
+	rc = get_unused_fd_flags(flags);
+	if (unlikely(rc < 0)) {
+		dev_err(dev, "%s: get_unused_fd_flags failed rc=%d\n",
+			__func__, rc);
+		goto err1;
+	}
+	fdtmp = rc;
+
+	/* Use default ops if there is no fops */
+	if (!fops)
+		fops = (struct file_operations *)&ocxl_afu_fops;
+
+	name = kasprintf(GFP_KERNEL, "ocxlflash:%d", ctx->pe);
+	file = ocxlflash_getfile(dev, name, fops, ctx, flags);
+	kfree(name);
+	if (IS_ERR(file)) {
+		rc = PTR_ERR(file);
+		dev_err(dev, "%s: ocxlflash_getfile failed rc=%d\n",
+			__func__, rc);
+		goto err2;
+	}
+
+	ctx->mapping = file->f_mapping;
+	*fd = fdtmp;
+out:
+	return file;
+err2:
+	put_unused_fd(fdtmp);
+err1:
+	file = ERR_PTR(rc);
+	goto out;
+}
+
 /* Backend ops to ocxlflash services */
 const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.module			= THIS_MODULE,
@@ -279,4 +478,5 @@ const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.release_context	= ocxlflash_release_context,
 	.create_afu		= ocxlflash_create_afu,
 	.destroy_afu		= ocxlflash_destroy_afu,
+	.get_fd			= ocxlflash_get_fd,
 };
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index a5337b6..55db005 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -33,6 +33,7 @@ struct ocxl_hw_afu {
 
 struct ocxlflash_context {
 	struct ocxl_hw_afu *hw_afu;	/* HW AFU back pointer */
+	struct address_space *mapping;	/* Mapping for pseudo filesystem */
 	bool master;			/* Whether this is a master context */
 	int pe;				/* Process element */
 };
-- 
2.1.0

[PATCH v3 14/41] cxlflash: Support adapter context discovery

[Uma Krishnan]

Provide means to obtain the process element of an adapter context as well
as locate an adapter context by file.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 49af059..21915b7 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -151,6 +151,19 @@ static struct file *ocxlflash_getfile(struct device *dev, const char *name,
 }
 
 /**
+ * ocxlflash_process_element() - get process element of the adapter context
+ * @ctx_cookie:	Adapter context associated with the process element.
+ *
+ * Return: process element of the adapter context
+ */
+static int ocxlflash_process_element(void *ctx_cookie)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+
+	return ctx->pe;
+}
+
+/**
  * ocxlflash_set_master() - sets the context as master
  * @ctx_cookie:	Adapter context to set as master.
  */
@@ -469,9 +482,21 @@ static struct file *ocxlflash_get_fd(void *ctx_cookie,
 	goto out;
 }
 
+/**
+ * ocxlflash_fops_get_context() - get the context associated with the file
+ * @file:	File associated with the adapter context.
+ *
+ * Return: pointer to the context
+ */
+static void *ocxlflash_fops_get_context(struct file *file)
+{
+	return file->private_data;
+}
+
 /* Backend ops to ocxlflash services */
 const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.module			= THIS_MODULE,
+	.process_element	= ocxlflash_process_element,
 	.set_master		= ocxlflash_set_master,
 	.get_context		= ocxlflash_get_context,
 	.dev_context_init	= ocxlflash_dev_context_init,
@@ -479,4 +504,5 @@ const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.create_afu		= ocxlflash_create_afu,
 	.destroy_afu		= ocxlflash_destroy_afu,
 	.get_fd			= ocxlflash_get_fd,
+	.fops_get_context	= ocxlflash_fops_get_context,
 };
-- 
2.1.0

[PATCH v3 14/41] cxlflash: Support adapter context discovery

[Uma Krishnan]

Provide means to obtain the process element of an adapter context as well
as locate an adapter context by file.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 49af059..21915b7 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -151,6 +151,19 @@ static struct file *ocxlflash_getfile(struct device *dev, const char *name,
 }
 
 /**
+ * ocxlflash_process_element() - get process element of the adapter context
+ * @ctx_cookie:	Adapter context associated with the process element.
+ *
+ * Return: process element of the adapter context
+ */
+static int ocxlflash_process_element(void *ctx_cookie)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+
+	return ctx->pe;
+}
+
+/**
  * ocxlflash_set_master() - sets the context as master
  * @ctx_cookie:	Adapter context to set as master.
  */
@@ -469,9 +482,21 @@ static struct file *ocxlflash_get_fd(void *ctx_cookie,
 	goto out;
 }
 
+/**
+ * ocxlflash_fops_get_context() - get the context associated with the file
+ * @file:	File associated with the adapter context.
+ *
+ * Return: pointer to the context
+ */
+static void *ocxlflash_fops_get_context(struct file *file)
+{
+	return file->private_data;
+}
+
 /* Backend ops to ocxlflash services */
 const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.module			= THIS_MODULE,
+	.process_element	= ocxlflash_process_element,
 	.set_master		= ocxlflash_set_master,
 	.get_context		= ocxlflash_get_context,
 	.dev_context_init	= ocxlflash_dev_context_init,
@@ -479,4 +504,5 @@ const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.create_afu		= ocxlflash_create_afu,
 	.destroy_afu		= ocxlflash_destroy_afu,
 	.get_fd			= ocxlflash_get_fd,
+	.fops_get_context	= ocxlflash_fops_get_context,
 };
-- 
2.1.0

[PATCH v3 15/41] cxlflash: Support image reload policy modification

[Uma Krishnan]

On a PERST, the AFU image can be reloaded or left intact. Provide means to
set this image reload policy.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 13 +++++++++++++
 drivers/scsi/cxlflash/ocxl_hw.h |  1 +
 2 files changed, 14 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 21915b7..f26bbb7 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -252,6 +252,18 @@ static int ocxlflash_release_context(void *ctx_cookie)
 }
 
 /**
+ * ocxlflash_perst_reloads_same_image() - sets the image reload policy
+ * @afu_cookie:	Hardware AFU associated with the host.
+ * @image:	Whether to load the same image on PERST.
+ */
+static void ocxlflash_perst_reloads_same_image(void *afu_cookie, bool image)
+{
+	struct ocxl_hw_afu *afu = afu_cookie;
+
+	afu->perst_same_image = image;
+}
+
+/**
  * ocxlflash_destroy_afu() - destroy the AFU structure
  * @afu_cookie:	AFU to be freed.
  */
@@ -501,6 +513,7 @@ const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.get_context		= ocxlflash_get_context,
 	.dev_context_init	= ocxlflash_dev_context_init,
 	.release_context	= ocxlflash_release_context,
+	.perst_reloads_same_image = ocxlflash_perst_reloads_same_image,
 	.create_afu		= ocxlflash_create_afu,
 	.destroy_afu		= ocxlflash_destroy_afu,
 	.get_fd			= ocxlflash_get_fd,
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index 55db005..b963871 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -17,6 +17,7 @@ struct ocxl_hw_afu {
 	struct ocxlflash_context *ocxl_ctx; /* Host context */
 	struct pci_dev *pdev;		/* PCI device */
 	struct device *dev;		/* Generic device */
+	bool perst_same_image;		/* Same image loaded on perst */
 
 	struct ocxl_fn_config fcfg;	/* DVSEC config of the function */
 	struct ocxl_afu_config acfg;	/* AFU configuration data */
-- 
2.1.0

[PATCH v3 15/41] cxlflash: Support image reload policy modification

[Uma Krishnan]

On a PERST, the AFU image can be reloaded or left intact. Provide means to
set this image reload policy.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 13 +++++++++++++
 drivers/scsi/cxlflash/ocxl_hw.h |  1 +
 2 files changed, 14 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 21915b7..f26bbb7 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -252,6 +252,18 @@ static int ocxlflash_release_context(void *ctx_cookie)
 }
 
 /**
+ * ocxlflash_perst_reloads_same_image() - sets the image reload policy
+ * @afu_cookie:	Hardware AFU associated with the host.
+ * @image:	Whether to load the same image on PERST.
+ */
+static void ocxlflash_perst_reloads_same_image(void *afu_cookie, bool image)
+{
+	struct ocxl_hw_afu *afu = afu_cookie;
+
+	afu->perst_same_image = image;
+}
+
+/**
  * ocxlflash_destroy_afu() - destroy the AFU structure
  * @afu_cookie:	AFU to be freed.
  */
@@ -501,6 +513,7 @@ const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.get_context		= ocxlflash_get_context,
 	.dev_context_init	= ocxlflash_dev_context_init,
 	.release_context	= ocxlflash_release_context,
+	.perst_reloads_same_image = ocxlflash_perst_reloads_same_image,
 	.create_afu		= ocxlflash_create_afu,
 	.destroy_afu		= ocxlflash_destroy_afu,
 	.get_fd			= ocxlflash_get_fd,
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index 55db005..b963871 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -17,6 +17,7 @@ struct ocxl_hw_afu {
 	struct ocxlflash_context *ocxl_ctx; /* Host context */
 	struct pci_dev *pdev;		/* PCI device */
 	struct device *dev;		/* Generic device */
+	bool perst_same_image;		/* Same image loaded on perst */
 
 	struct ocxl_fn_config fcfg;	/* DVSEC config of the function */
 	struct ocxl_afu_config acfg;	/* AFU configuration data */
-- 
2.1.0

[PATCH v3 16/41] cxlflash: MMIO map the AFU

[Uma Krishnan]

When the AFU is configured, the global and per process MMIO regions
are presented by the configuration space. Save these regions and
map the global MMIO region that is used to access all of the control
and provisioning data in the AFU.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 74 ++++++++++++++++++++++++++++++++++++++++-
 drivers/scsi/cxlflash/ocxl_hw.h |  4 +++
 2 files changed, 77 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index f26bbb7..2358034 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -264,6 +264,18 @@ static void ocxlflash_perst_reloads_same_image(void *afu_cookie, bool image)
 }
 
 /**
+ * ocxlflash_unconfig_afu() - unconfigure the AFU
+ * @afu: AFU associated with the host.
+ */
+static void ocxlflash_unconfig_afu(struct ocxl_hw_afu *afu)
+{
+	if (afu->gmmio_virt) {
+		iounmap(afu->gmmio_virt);
+		afu->gmmio_virt = NULL;
+	}
+}
+
+/**
  * ocxlflash_destroy_afu() - destroy the AFU structure
  * @afu_cookie:	AFU to be freed.
  */
@@ -276,6 +288,7 @@ static void ocxlflash_destroy_afu(void *afu_cookie)
 
 	ocxlflash_release_context(afu->ocxl_ctx);
 	idr_destroy(&afu->idr);
+	ocxlflash_unconfig_afu(afu);
 	kfree(afu);
 }
 
@@ -327,6 +340,56 @@ static int ocxlflash_config_fn(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
 }
 
 /**
+ * ocxlflash_map_mmio() - map the AFU MMIO space
+ * @afu: AFU associated with the host.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_map_mmio(struct ocxl_hw_afu *afu)
+{
+	struct ocxl_afu_config *acfg = &afu->acfg;
+	struct pci_dev *pdev = afu->pdev;
+	struct device *dev = afu->dev;
+	phys_addr_t gmmio, ppmmio;
+	int rc = 0;
+
+	rc = pci_request_region(pdev, acfg->global_mmio_bar, "ocxlflash");
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: pci_request_region for global failed rc=%d\n",
+			__func__, rc);
+		goto out;
+	}
+	gmmio = pci_resource_start(pdev, acfg->global_mmio_bar);
+	gmmio += acfg->global_mmio_offset;
+
+	rc = pci_request_region(pdev, acfg->pp_mmio_bar, "ocxlflash");
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: pci_request_region for pp bar failed rc=%d\n",
+			__func__, rc);
+		goto err1;
+	}
+	ppmmio = pci_resource_start(pdev, acfg->pp_mmio_bar);
+	ppmmio += acfg->pp_mmio_offset;
+
+	afu->gmmio_virt = ioremap(gmmio, acfg->global_mmio_size);
+	if (unlikely(!afu->gmmio_virt)) {
+		dev_err(dev, "%s: MMIO mapping failed\n", __func__);
+		rc = -ENOMEM;
+		goto err2;
+	}
+
+	afu->gmmio_phys = gmmio;
+	afu->ppmmio_phys = ppmmio;
+out:
+	return rc;
+err2:
+	pci_release_region(pdev, acfg->pp_mmio_bar);
+err1:
+	pci_release_region(pdev, acfg->global_mmio_bar);
+	goto out;
+}
+
+/**
  * ocxlflash_config_afu() - configure the host AFU
  * @pdev:	PCI device associated with the host.
  * @afu:	AFU associated with the host.
@@ -369,6 +432,13 @@ static int ocxlflash_config_afu(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
 	afu->max_pasid = 1 << acfg->pasid_supported_log;
 
 	ocxl_config_set_afu_pasid(pdev, pos, 0, acfg->pasid_supported_log);
+
+	rc = ocxlflash_map_mmio(afu);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: ocxlflash_map_mmio failed rc=%d\n",
+			__func__, rc);
+		goto out;
+	}
 out:
 	return rc;
 }
@@ -415,12 +485,14 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
 		rc = PTR_ERR(ctx);
 		dev_err(dev, "%s: ocxlflash_dev_context_init failed rc=%d\n",
 			__func__, rc);
-		goto err1;
+		goto err2;
 	}
 
 	afu->ocxl_ctx = ctx;
 out:
 	return afu;
+err2:
+	ocxlflash_unconfig_afu(afu);
 err1:
 	idr_destroy(&afu->idr);
 	kfree(afu);
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index b963871..18236e6 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -27,6 +27,10 @@ struct ocxl_hw_afu {
 	int afu_actag_base;		/* AFU acTag base */
 	int afu_actag_enabled;		/* AFU acTag number enabled */
 
+	phys_addr_t ppmmio_phys;	/* Per process MMIO space */
+	phys_addr_t gmmio_phys;		/* Global AFU MMIO space */
+	void __iomem *gmmio_virt;	/* Global MMIO map */
+
 	struct idr idr;			/* IDR to manage contexts */
 	int max_pasid;			/* Maximum number of contexts */
 	bool is_present;		/* Function has AFUs defined */
-- 
2.1.0

[PATCH v3 16/41] cxlflash: MMIO map the AFU

[Uma Krishnan]

When the AFU is configured, the global and per process MMIO regions
are presented by the configuration space. Save these regions and
map the global MMIO region that is used to access all of the control
and provisioning data in the AFU.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 74 ++++++++++++++++++++++++++++++++++++++++-
 drivers/scsi/cxlflash/ocxl_hw.h |  4 +++
 2 files changed, 77 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index f26bbb7..2358034 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -264,6 +264,18 @@ static void ocxlflash_perst_reloads_same_image(void *afu_cookie, bool image)
 }
 
 /**
+ * ocxlflash_unconfig_afu() - unconfigure the AFU
+ * @afu: AFU associated with the host.
+ */
+static void ocxlflash_unconfig_afu(struct ocxl_hw_afu *afu)
+{
+	if (afu->gmmio_virt) {
+		iounmap(afu->gmmio_virt);
+		afu->gmmio_virt = NULL;
+	}
+}
+
+/**
  * ocxlflash_destroy_afu() - destroy the AFU structure
  * @afu_cookie:	AFU to be freed.
  */
@@ -276,6 +288,7 @@ static void ocxlflash_destroy_afu(void *afu_cookie)
 
 	ocxlflash_release_context(afu->ocxl_ctx);
 	idr_destroy(&afu->idr);
+	ocxlflash_unconfig_afu(afu);
 	kfree(afu);
 }
 
@@ -327,6 +340,56 @@ static int ocxlflash_config_fn(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
 }
 
 /**
+ * ocxlflash_map_mmio() - map the AFU MMIO space
+ * @afu: AFU associated with the host.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_map_mmio(struct ocxl_hw_afu *afu)
+{
+	struct ocxl_afu_config *acfg = &afu->acfg;
+	struct pci_dev *pdev = afu->pdev;
+	struct device *dev = afu->dev;
+	phys_addr_t gmmio, ppmmio;
+	int rc = 0;
+
+	rc = pci_request_region(pdev, acfg->global_mmio_bar, "ocxlflash");
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: pci_request_region for global failed rc=%d\n",
+			__func__, rc);
+		goto out;
+	}
+	gmmio = pci_resource_start(pdev, acfg->global_mmio_bar);
+	gmmio += acfg->global_mmio_offset;
+
+	rc = pci_request_region(pdev, acfg->pp_mmio_bar, "ocxlflash");
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: pci_request_region for pp bar failed rc=%d\n",
+			__func__, rc);
+		goto err1;
+	}
+	ppmmio = pci_resource_start(pdev, acfg->pp_mmio_bar);
+	ppmmio += acfg->pp_mmio_offset;
+
+	afu->gmmio_virt = ioremap(gmmio, acfg->global_mmio_size);
+	if (unlikely(!afu->gmmio_virt)) {
+		dev_err(dev, "%s: MMIO mapping failed\n", __func__);
+		rc = -ENOMEM;
+		goto err2;
+	}
+
+	afu->gmmio_phys = gmmio;
+	afu->ppmmio_phys = ppmmio;
+out:
+	return rc;
+err2:
+	pci_release_region(pdev, acfg->pp_mmio_bar);
+err1:
+	pci_release_region(pdev, acfg->global_mmio_bar);
+	goto out;
+}
+
+/**
  * ocxlflash_config_afu() - configure the host AFU
  * @pdev:	PCI device associated with the host.
  * @afu:	AFU associated with the host.
@@ -369,6 +432,13 @@ static int ocxlflash_config_afu(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
 	afu->max_pasid = 1 << acfg->pasid_supported_log;
 
 	ocxl_config_set_afu_pasid(pdev, pos, 0, acfg->pasid_supported_log);
+
+	rc = ocxlflash_map_mmio(afu);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: ocxlflash_map_mmio failed rc=%d\n",
+			__func__, rc);
+		goto out;
+	}
 out:
 	return rc;
 }
@@ -415,12 +485,14 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
 		rc = PTR_ERR(ctx);
 		dev_err(dev, "%s: ocxlflash_dev_context_init failed rc=%d\n",
 			__func__, rc);
-		goto err1;
+		goto err2;
 	}
 
 	afu->ocxl_ctx = ctx;
 out:
 	return afu;
+err2:
+	ocxlflash_unconfig_afu(afu);
 err1:
 	idr_destroy(&afu->idr);
 	kfree(afu);
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index b963871..18236e6 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -27,6 +27,10 @@ struct ocxl_hw_afu {
 	int afu_actag_base;		/* AFU acTag base */
 	int afu_actag_enabled;		/* AFU acTag number enabled */
 
+	phys_addr_t ppmmio_phys;	/* Per process MMIO space */
+	phys_addr_t gmmio_phys;		/* Global AFU MMIO space */
+	void __iomem *gmmio_virt;	/* Global MMIO map */
+
 	struct idr idr;			/* IDR to manage contexts */
 	int max_pasid;			/* Maximum number of contexts */
 	bool is_present;		/* Function has AFUs defined */
-- 
2.1.0

[PATCH v3 17/41] cxlflash: Support starting an adapter context

[Uma Krishnan]

Once the adapter context is created, it needs to be started by assigning
the MMIO space for the context and by enabling the process element in the
link. This commit adds the skeleton for starting the context and assigns
the context specific MMIO space. Master contexts have access to the global
MMIO space while the rest have access to the context specific space.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 39 +++++++++++++++++++++++++++++++++++++++
 drivers/scsi/cxlflash/ocxl_hw.h |  3 +++
 2 files changed, 42 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 2358034..b39a03d 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -164,6 +164,44 @@ static int ocxlflash_process_element(void *ctx_cookie)
 }
 
 /**
+ * start_context() - local routine to start a context
+ * @ctx:	Adapter context to be started.
+ *
+ * Assign the context specific MMIO space.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int start_context(struct ocxlflash_context *ctx)
+{
+	struct ocxl_hw_afu *afu = ctx->hw_afu;
+	struct ocxl_afu_config *acfg = &afu->acfg;
+	bool master = ctx->master;
+
+	if (master) {
+		ctx->psn_size = acfg->global_mmio_size;
+		ctx->psn_phys = afu->gmmio_phys;
+	} else {
+		ctx->psn_size = acfg->pp_mmio_stride;
+		ctx->psn_phys = afu->ppmmio_phys + (ctx->pe * ctx->psn_size);
+	}
+
+	return 0;
+}
+
+/**
+ * ocxlflash_start_context() - start a kernel context
+ * @ctx_cookie:	Adapter context to be started.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_start_context(void *ctx_cookie)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+
+	return start_context(ctx);
+}
+
+/**
  * ocxlflash_set_master() - sets the context as master
  * @ctx_cookie:	Adapter context to set as master.
  */
@@ -581,6 +619,7 @@ static void *ocxlflash_fops_get_context(struct file *file)
 const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.module			= THIS_MODULE,
 	.process_element	= ocxlflash_process_element,
+	.start_context		= ocxlflash_start_context,
 	.set_master		= ocxlflash_set_master,
 	.get_context		= ocxlflash_get_context,
 	.dev_context_init	= ocxlflash_dev_context_init,
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index 18236e6..ee19717 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -41,4 +41,7 @@ struct ocxlflash_context {
 	struct address_space *mapping;	/* Mapping for pseudo filesystem */
 	bool master;			/* Whether this is a master context */
 	int pe;				/* Process element */
+
+	phys_addr_t psn_phys;		/* Process mapping */
+	u64 psn_size;			/* Process mapping size */
 };
-- 
2.1.0

[PATCH v3 17/41] cxlflash: Support starting an adapter context

[Uma Krishnan]

Once the adapter context is created, it needs to be started by assigning
the MMIO space for the context and by enabling the process element in the
link. This commit adds the skeleton for starting the context and assigns
the context specific MMIO space. Master contexts have access to the global
MMIO space while the rest have access to the context specific space.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 39 +++++++++++++++++++++++++++++++++++++++
 drivers/scsi/cxlflash/ocxl_hw.h |  3 +++
 2 files changed, 42 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 2358034..b39a03d 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -164,6 +164,44 @@ static int ocxlflash_process_element(void *ctx_cookie)
 }
 
 /**
+ * start_context() - local routine to start a context
+ * @ctx:	Adapter context to be started.
+ *
+ * Assign the context specific MMIO space.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int start_context(struct ocxlflash_context *ctx)
+{
+	struct ocxl_hw_afu *afu = ctx->hw_afu;
+	struct ocxl_afu_config *acfg = &afu->acfg;
+	bool master = ctx->master;
+
+	if (master) {
+		ctx->psn_size = acfg->global_mmio_size;
+		ctx->psn_phys = afu->gmmio_phys;
+	} else {
+		ctx->psn_size = acfg->pp_mmio_stride;
+		ctx->psn_phys = afu->ppmmio_phys + (ctx->pe * ctx->psn_size);
+	}
+
+	return 0;
+}
+
+/**
+ * ocxlflash_start_context() - start a kernel context
+ * @ctx_cookie:	Adapter context to be started.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_start_context(void *ctx_cookie)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+
+	return start_context(ctx);
+}
+
+/**
  * ocxlflash_set_master() - sets the context as master
  * @ctx_cookie:	Adapter context to set as master.
  */
@@ -581,6 +619,7 @@ static void *ocxlflash_fops_get_context(struct file *file)
 const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.module			= THIS_MODULE,
 	.process_element	= ocxlflash_process_element,
+	.start_context		= ocxlflash_start_context,
 	.set_master		= ocxlflash_set_master,
 	.get_context		= ocxlflash_get_context,
 	.dev_context_init	= ocxlflash_dev_context_init,
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index 18236e6..ee19717 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -41,4 +41,7 @@ struct ocxlflash_context {
 	struct address_space *mapping;	/* Mapping for pseudo filesystem */
 	bool master;			/* Whether this is a master context */
 	int pe;				/* Process element */
+
+	phys_addr_t psn_phys;		/* Process mapping */
+	u64 psn_size;			/* Process mapping size */
 };
-- 
2.1.0

[PATCH v3 18/41] cxlflash: Support process specific mappings

[Uma Krishnan]

Once the context is started, the assigned MMIO space can be mapped
and unmapped. Provide means to map and unmap the context MMIO space.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index b39a03d..73b0b10 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -151,6 +151,28 @@ static struct file *ocxlflash_getfile(struct device *dev, const char *name,
 }
 
 /**
+ * ocxlflash_psa_map() - map the process specific MMIO space
+ * @ctx_cookie:	Adapter context for which the mapping needs to be done.
+ *
+ * Return: MMIO pointer of the mapped region
+ */
+static void __iomem *ocxlflash_psa_map(void *ctx_cookie)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+
+	return ioremap(ctx->psn_phys, ctx->psn_size);
+}
+
+/**
+ * ocxlflash_psa_unmap() - unmap the process specific MMIO space
+ * @addr:	MMIO pointer to unmap.
+ */
+static void ocxlflash_psa_unmap(void __iomem *addr)
+{
+	iounmap(addr);
+}
+
+/**
  * ocxlflash_process_element() - get process element of the adapter context
  * @ctx_cookie:	Adapter context associated with the process element.
  *
@@ -618,6 +640,8 @@ static void *ocxlflash_fops_get_context(struct file *file)
 /* Backend ops to ocxlflash services */
 const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.module			= THIS_MODULE,
+	.psa_map		= ocxlflash_psa_map,
+	.psa_unmap		= ocxlflash_psa_unmap,
 	.process_element	= ocxlflash_process_element,
 	.start_context		= ocxlflash_start_context,
 	.set_master		= ocxlflash_set_master,
-- 
2.1.0

[PATCH v3 18/41] cxlflash: Support process specific mappings

[Uma Krishnan]

Once the context is started, the assigned MMIO space can be mapped
and unmapped. Provide means to map and unmap the context MMIO space.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index b39a03d..73b0b10 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -151,6 +151,28 @@ static struct file *ocxlflash_getfile(struct device *dev, const char *name,
 }
 
 /**
+ * ocxlflash_psa_map() - map the process specific MMIO space
+ * @ctx_cookie:	Adapter context for which the mapping needs to be done.
+ *
+ * Return: MMIO pointer of the mapped region
+ */
+static void __iomem *ocxlflash_psa_map(void *ctx_cookie)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+
+	return ioremap(ctx->psn_phys, ctx->psn_size);
+}
+
+/**
+ * ocxlflash_psa_unmap() - unmap the process specific MMIO space
+ * @addr:	MMIO pointer to unmap.
+ */
+static void ocxlflash_psa_unmap(void __iomem *addr)
+{
+	iounmap(addr);
+}
+
+/**
  * ocxlflash_process_element() - get process element of the adapter context
  * @ctx_cookie:	Adapter context associated with the process element.
  *
@@ -618,6 +640,8 @@ static void *ocxlflash_fops_get_context(struct file *file)
 /* Backend ops to ocxlflash services */
 const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.module			= THIS_MODULE,
+	.psa_map		= ocxlflash_psa_map,
+	.psa_unmap		= ocxlflash_psa_unmap,
 	.process_element	= ocxlflash_process_element,
 	.start_context		= ocxlflash_start_context,
 	.set_master		= ocxlflash_set_master,
-- 
2.1.0

[PATCH v3 19/41] cxlflash: Support AFU state toggling

[Uma Krishnan]

The AFU should be enabled following a successful configuration and
disabled near the end of the cleanup path.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 73b0b10..3042057 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -342,12 +342,18 @@ static void ocxlflash_unconfig_afu(struct ocxl_hw_afu *afu)
 static void ocxlflash_destroy_afu(void *afu_cookie)
 {
 	struct ocxl_hw_afu *afu = afu_cookie;
+	int pos;
 
 	if (!afu)
 		return;
 
 	ocxlflash_release_context(afu->ocxl_ctx);
 	idr_destroy(&afu->idr);
+
+	/* Disable the AFU */
+	pos = afu->acfg.dvsec_afu_control_pos;
+	ocxl_config_set_afu_state(afu->pdev, pos, 0);
+
 	ocxlflash_unconfig_afu(afu);
 	kfree(afu);
 }
@@ -499,6 +505,9 @@ static int ocxlflash_config_afu(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
 			__func__, rc);
 		goto out;
 	}
+
+	/* Enable the AFU */
+	ocxl_config_set_afu_state(pdev, acfg->dvsec_afu_control_pos, 1);
 out:
 	return rc;
 }
-- 
2.1.0

[PATCH v3 19/41] cxlflash: Support AFU state toggling

[Uma Krishnan]

The AFU should be enabled following a successful configuration and
disabled near the end of the cleanup path.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 73b0b10..3042057 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -342,12 +342,18 @@ static void ocxlflash_unconfig_afu(struct ocxl_hw_afu *afu)
 static void ocxlflash_destroy_afu(void *afu_cookie)
 {
 	struct ocxl_hw_afu *afu = afu_cookie;
+	int pos;
 
 	if (!afu)
 		return;
 
 	ocxlflash_release_context(afu->ocxl_ctx);
 	idr_destroy(&afu->idr);
+
+	/* Disable the AFU */
+	pos = afu->acfg.dvsec_afu_control_pos;
+	ocxl_config_set_afu_state(afu->pdev, pos, 0);
+
 	ocxlflash_unconfig_afu(afu);
 	kfree(afu);
 }
@@ -499,6 +505,9 @@ static int ocxlflash_config_afu(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
 			__func__, rc);
 		goto out;
 	}
+
+	/* Enable the AFU */
+	ocxl_config_set_afu_state(pdev, acfg->dvsec_afu_control_pos, 1);
 out:
 	return rc;
 }
-- 
2.1.0

[PATCH v3 20/41] cxlflash: Support reading adapter VPD data

[Uma Krishnan]

Use the PCI VPD services to support reading the VPD data of the
underlying adapter.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 3042057..a2f04d3 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -324,6 +324,20 @@ static void ocxlflash_perst_reloads_same_image(void *afu_cookie, bool image)
 }
 
 /**
+ * ocxlflash_read_adapter_vpd() - reads the adapter VPD
+ * @pdev:	PCI device associated with the host.
+ * @buf:	Buffer to get the VPD data.
+ * @count:	Size of buffer (maximum bytes that can be read).
+ *
+ * Return: size of VPD on success, -errno on failure
+ */
+static ssize_t ocxlflash_read_adapter_vpd(struct pci_dev *pdev, void *buf,
+					  size_t count)
+{
+	return pci_read_vpd(pdev, 0, count, buf);
+}
+
+/**
  * ocxlflash_unconfig_afu() - unconfigure the AFU
  * @afu: AFU associated with the host.
  */
@@ -658,6 +672,7 @@ const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.dev_context_init	= ocxlflash_dev_context_init,
 	.release_context	= ocxlflash_release_context,
 	.perst_reloads_same_image = ocxlflash_perst_reloads_same_image,
+	.read_adapter_vpd	= ocxlflash_read_adapter_vpd,
 	.create_afu		= ocxlflash_create_afu,
 	.destroy_afu		= ocxlflash_destroy_afu,
 	.get_fd			= ocxlflash_get_fd,
-- 
2.1.0

[PATCH v3 20/41] cxlflash: Support reading adapter VPD data

[Uma Krishnan]

Use the PCI VPD services to support reading the VPD data of the
underlying adapter.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 3042057..a2f04d3 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -324,6 +324,20 @@ static void ocxlflash_perst_reloads_same_image(void *afu_cookie, bool image)
 }
 
 /**
+ * ocxlflash_read_adapter_vpd() - reads the adapter VPD
+ * @pdev:	PCI device associated with the host.
+ * @buf:	Buffer to get the VPD data.
+ * @count:	Size of buffer (maximum bytes that can be read).
+ *
+ * Return: size of VPD on success, -errno on failure
+ */
+static ssize_t ocxlflash_read_adapter_vpd(struct pci_dev *pdev, void *buf,
+					  size_t count)
+{
+	return pci_read_vpd(pdev, 0, count, buf);
+}
+
+/**
  * ocxlflash_unconfig_afu() - unconfigure the AFU
  * @afu: AFU associated with the host.
  */
@@ -658,6 +672,7 @@ const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.dev_context_init	= ocxlflash_dev_context_init,
 	.release_context	= ocxlflash_release_context,
 	.perst_reloads_same_image = ocxlflash_perst_reloads_same_image,
+	.read_adapter_vpd	= ocxlflash_read_adapter_vpd,
 	.create_afu		= ocxlflash_create_afu,
 	.destroy_afu		= ocxlflash_destroy_afu,
 	.get_fd			= ocxlflash_get_fd,
-- 
2.1.0

[PATCH v3 21/41] cxlflash: Setup function OCXL link

[Uma Krishnan]

After reading and modifying the function configuration, setup the OCXL
link using the OCXL provider services. The link is released when the
adapter is unconfigured.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 25 ++++++++++++++++++++++---
 drivers/scsi/cxlflash/ocxl_hw.h |  1 +
 2 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index a2f04d3..67517f8 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -415,11 +415,28 @@ static int ocxlflash_config_fn(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
 	ocxl_config_set_actag(pdev, fcfg->dvsec_function_pos, base, enabled);
 	dev_dbg(dev, "%s: Function acTag range base=%u enabled=%u\n",
 		__func__, base, enabled);
+
+	rc = ocxl_link_setup(pdev, 0, &afu->link_token);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: ocxl_link_setup failed rc=%d\n",
+			__func__, rc);
+		goto out;
+	}
 out:
 	return rc;
 }
 
 /**
+ * ocxlflash_unconfig_fn() - unconfigure the host function
+ * @pdev:	PCI device associated with the host.
+ * @afu:	AFU associated with the host.
+ */
+static void ocxlflash_unconfig_fn(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
+{
+	ocxl_link_release(pdev, afu->link_token);
+}
+
+/**
  * ocxlflash_map_mmio() - map the AFU MMIO space
  * @afu: AFU associated with the host.
  *
@@ -560,7 +577,7 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
 	if (unlikely(rc)) {
 		dev_err(dev, "%s: AFU configuration failed rc=%d\n",
 			__func__, rc);
-		goto err1;
+		goto err2;
 	}
 
 	ctx = ocxlflash_dev_context_init(pdev, afu);
@@ -568,14 +585,16 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
 		rc = PTR_ERR(ctx);
 		dev_err(dev, "%s: ocxlflash_dev_context_init failed rc=%d\n",
 			__func__, rc);
-		goto err2;
+		goto err3;
 	}
 
 	afu->ocxl_ctx = ctx;
 out:
 	return afu;
-err2:
+err3:
 	ocxlflash_unconfig_afu(afu);
+err2:
+	ocxlflash_unconfig_fn(pdev, afu);
 err1:
 	idr_destroy(&afu->idr);
 	kfree(afu);
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index ee19717..09fa94c 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -31,6 +31,7 @@ struct ocxl_hw_afu {
 	phys_addr_t gmmio_phys;		/* Global AFU MMIO space */
 	void __iomem *gmmio_virt;	/* Global MMIO map */
 
+	void *link_token;		/* Link token for the SPA */
 	struct idr idr;			/* IDR to manage contexts */
 	int max_pasid;			/* Maximum number of contexts */
 	bool is_present;		/* Function has AFUs defined */
-- 
2.1.0

[PATCH v3 21/41] cxlflash: Setup function OCXL link

[Uma Krishnan]

After reading and modifying the function configuration, setup the OCXL
link using the OCXL provider services. The link is released when the
adapter is unconfigured.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 25 ++++++++++++++++++++++---
 drivers/scsi/cxlflash/ocxl_hw.h |  1 +
 2 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index a2f04d3..67517f8 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -415,11 +415,28 @@ static int ocxlflash_config_fn(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
 	ocxl_config_set_actag(pdev, fcfg->dvsec_function_pos, base, enabled);
 	dev_dbg(dev, "%s: Function acTag range base=%u enabled=%u\n",
 		__func__, base, enabled);
+
+	rc = ocxl_link_setup(pdev, 0, &afu->link_token);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: ocxl_link_setup failed rc=%d\n",
+			__func__, rc);
+		goto out;
+	}
 out:
 	return rc;
 }
 
 /**
+ * ocxlflash_unconfig_fn() - unconfigure the host function
+ * @pdev:	PCI device associated with the host.
+ * @afu:	AFU associated with the host.
+ */
+static void ocxlflash_unconfig_fn(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
+{
+	ocxl_link_release(pdev, afu->link_token);
+}
+
+/**
  * ocxlflash_map_mmio() - map the AFU MMIO space
  * @afu: AFU associated with the host.
  *
@@ -560,7 +577,7 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
 	if (unlikely(rc)) {
 		dev_err(dev, "%s: AFU configuration failed rc=%d\n",
 			__func__, rc);
-		goto err1;
+		goto err2;
 	}
 
 	ctx = ocxlflash_dev_context_init(pdev, afu);
@@ -568,14 +585,16 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
 		rc = PTR_ERR(ctx);
 		dev_err(dev, "%s: ocxlflash_dev_context_init failed rc=%d\n",
 			__func__, rc);
-		goto err2;
+		goto err3;
 	}
 
 	afu->ocxl_ctx = ctx;
 out:
 	return afu;
-err2:
+err3:
 	ocxlflash_unconfig_afu(afu);
+err2:
+	ocxlflash_unconfig_fn(pdev, afu);
 err1:
 	idr_destroy(&afu->idr);
 	kfree(afu);
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index ee19717..09fa94c 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -31,6 +31,7 @@ struct ocxl_hw_afu {
 	phys_addr_t gmmio_phys;		/* Global AFU MMIO space */
 	void __iomem *gmmio_virt;	/* Global MMIO map */
 
+	void *link_token;		/* Link token for the SPA */
 	struct idr idr;			/* IDR to manage contexts */
 	int max_pasid;			/* Maximum number of contexts */
 	bool is_present;		/* Function has AFUs defined */
-- 
2.1.0

[PATCH v3 22/41] cxlflash: Setup OCXL transaction layer

[Uma Krishnan]

The first function of the link needs to configure the transaction layer
between the host and device. This is accomplished by a call to the OCXL
provider services.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 67517f8..db612bd 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -422,8 +422,18 @@ static int ocxlflash_config_fn(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
 			__func__, rc);
 		goto out;
 	}
+
+	rc = ocxl_config_set_TL(pdev, fcfg->dvsec_tl_pos);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: ocxl_config_set_TL failed rc=%d\n",
+			__func__, rc);
+		goto err;
+	}
 out:
 	return rc;
+err:
+	ocxl_link_release(pdev, afu->link_token);
+	goto out;
 }
 
 /**
-- 
2.1.0

[PATCH v3 22/41] cxlflash: Setup OCXL transaction layer

[Uma Krishnan]

The first function of the link needs to configure the transaction layer
between the host and device. This is accomplished by a call to the OCXL
provider services.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 67517f8..db612bd 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -422,8 +422,18 @@ static int ocxlflash_config_fn(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
 			__func__, rc);
 		goto out;
 	}
+
+	rc = ocxl_config_set_TL(pdev, fcfg->dvsec_tl_pos);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: ocxl_config_set_TL failed rc=%d\n",
+			__func__, rc);
+		goto err;
+	}
 out:
 	return rc;
+err:
+	ocxl_link_release(pdev, afu->link_token);
+	goto out;
 }
 
 /**
-- 
2.1.0

[PATCH v3 23/41] cxlflash: Support process element lifecycle

[Uma Krishnan]

As part of the context lifecycle, the associated process element within
the Shared Process Area (SPA) of the link must be updated. Each process
is defined by various parameters (pid, tid, PASID mm) that are stored in
the SPA upon starting a context and invalidated when a context is stopped.

Use the OCXL provider services to configure the SPA with the appropriate
data that is unique to the process when starting a context. Initially only
kernel contexts are supported and therefore these process values are not
applicable. Note that the OCXL service used has an optional callback for
translation fault error notification. While not used here, it will be
expanded in a future commit.

Also add a service to stop a context by terminating the corresponding
PASID and remove the process element from the SPA.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 52 +++++++++++++++++++++++++++++++++++++++--
 1 file changed, 50 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index db612bd..8d21f94 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -189,7 +189,7 @@ static int ocxlflash_process_element(void *ctx_cookie)
  * start_context() - local routine to start a context
  * @ctx:	Adapter context to be started.
  *
- * Assign the context specific MMIO space.
+ * Assign the context specific MMIO space, add and enable the PE.
  *
  * Return: 0 on success, -errno on failure
  */
@@ -197,7 +197,10 @@ static int start_context(struct ocxlflash_context *ctx)
 {
 	struct ocxl_hw_afu *afu = ctx->hw_afu;
 	struct ocxl_afu_config *acfg = &afu->acfg;
+	void *link_token = afu->link_token;
+	struct device *dev = afu->dev;
 	bool master = ctx->master;
+	int rc = 0;
 
 	if (master) {
 		ctx->psn_size = acfg->global_mmio_size;
@@ -207,7 +210,16 @@ static int start_context(struct ocxlflash_context *ctx)
 		ctx->psn_phys = afu->ppmmio_phys + (ctx->pe * ctx->psn_size);
 	}
 
-	return 0;
+
+	/* pid, tid, amr and mm are zeroes/NULL for a kernel context */
+	rc = ocxl_link_add_pe(link_token, ctx->pe, 0, 0, 0, NULL, NULL, NULL);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: ocxl_link_add_pe failed rc=%d\n",
+			__func__, rc);
+		goto out;
+	}
+out:
+	return rc;
 }
 
 /**
@@ -224,6 +236,41 @@ static int ocxlflash_start_context(void *ctx_cookie)
 }
 
 /**
+ * ocxlflash_stop_context() - stop a context
+ * @ctx_cookie:	Adapter context to be stopped.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_stop_context(void *ctx_cookie)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+	struct ocxl_hw_afu *afu = ctx->hw_afu;
+	struct ocxl_afu_config *acfg = &afu->acfg;
+	struct pci_dev *pdev = afu->pdev;
+	struct device *dev = afu->dev;
+	int rc;
+
+	rc = ocxl_config_terminate_pasid(pdev, acfg->dvsec_afu_control_pos,
+					 ctx->pe);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: ocxl_config_terminate_pasid failed rc=%d\n",
+			__func__, rc);
+		/* If EBUSY, PE could be referenced in future by the AFU */
+		if (rc == -EBUSY)
+			goto out;
+	}
+
+	rc = ocxl_link_remove_pe(afu->link_token, ctx->pe);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: ocxl_link_remove_pe failed rc=%d\n",
+			__func__, rc);
+		goto out;
+	}
+out:
+	return rc;
+}
+
+/**
  * ocxlflash_set_master() - sets the context as master
  * @ctx_cookie:	Adapter context to set as master.
  */
@@ -696,6 +743,7 @@ const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.psa_unmap		= ocxlflash_psa_unmap,
 	.process_element	= ocxlflash_process_element,
 	.start_context		= ocxlflash_start_context,
+	.stop_context		= ocxlflash_stop_context,
 	.set_master		= ocxlflash_set_master,
 	.get_context		= ocxlflash_get_context,
 	.dev_context_init	= ocxlflash_dev_context_init,
-- 
2.1.0

[PATCH v3 23/41] cxlflash: Support process element lifecycle

[Uma Krishnan]

As part of the context lifecycle, the associated process element within
the Shared Process Area (SPA) of the link must be updated. Each process
is defined by various parameters (pid, tid, PASID mm) that are stored in
the SPA upon starting a context and invalidated when a context is stopped.

Use the OCXL provider services to configure the SPA with the appropriate
data that is unique to the process when starting a context. Initially only
kernel contexts are supported and therefore these process values are not
applicable. Note that the OCXL service used has an optional callback for
translation fault error notification. While not used here, it will be
expanded in a future commit.

Also add a service to stop a context by terminating the corresponding
PASID and remove the process element from the SPA.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 52 +++++++++++++++++++++++++++++++++++++++--
 1 file changed, 50 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index db612bd..8d21f94 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -189,7 +189,7 @@ static int ocxlflash_process_element(void *ctx_cookie)
  * start_context() - local routine to start a context
  * @ctx:	Adapter context to be started.
  *
- * Assign the context specific MMIO space.
+ * Assign the context specific MMIO space, add and enable the PE.
  *
  * Return: 0 on success, -errno on failure
  */
@@ -197,7 +197,10 @@ static int start_context(struct ocxlflash_context *ctx)
 {
 	struct ocxl_hw_afu *afu = ctx->hw_afu;
 	struct ocxl_afu_config *acfg = &afu->acfg;
+	void *link_token = afu->link_token;
+	struct device *dev = afu->dev;
 	bool master = ctx->master;
+	int rc = 0;
 
 	if (master) {
 		ctx->psn_size = acfg->global_mmio_size;
@@ -207,7 +210,16 @@ static int start_context(struct ocxlflash_context *ctx)
 		ctx->psn_phys = afu->ppmmio_phys + (ctx->pe * ctx->psn_size);
 	}
 
-	return 0;
+
+	/* pid, tid, amr and mm are zeroes/NULL for a kernel context */
+	rc = ocxl_link_add_pe(link_token, ctx->pe, 0, 0, 0, NULL, NULL, NULL);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: ocxl_link_add_pe failed rc=%d\n",
+			__func__, rc);
+		goto out;
+	}
+out:
+	return rc;
 }
 
 /**
@@ -224,6 +236,41 @@ static int ocxlflash_start_context(void *ctx_cookie)
 }
 
 /**
+ * ocxlflash_stop_context() - stop a context
+ * @ctx_cookie:	Adapter context to be stopped.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_stop_context(void *ctx_cookie)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+	struct ocxl_hw_afu *afu = ctx->hw_afu;
+	struct ocxl_afu_config *acfg = &afu->acfg;
+	struct pci_dev *pdev = afu->pdev;
+	struct device *dev = afu->dev;
+	int rc;
+
+	rc = ocxl_config_terminate_pasid(pdev, acfg->dvsec_afu_control_pos,
+					 ctx->pe);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: ocxl_config_terminate_pasid failed rc=%d\n",
+			__func__, rc);
+		/* If EBUSY, PE could be referenced in future by the AFU */
+		if (rc == -EBUSY)
+			goto out;
+	}
+
+	rc = ocxl_link_remove_pe(afu->link_token, ctx->pe);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: ocxl_link_remove_pe failed rc=%d\n",
+			__func__, rc);
+		goto out;
+	}
+out:
+	return rc;
+}
+
+/**
  * ocxlflash_set_master() - sets the context as master
  * @ctx_cookie:	Adapter context to set as master.
  */
@@ -696,6 +743,7 @@ const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.psa_unmap		= ocxlflash_psa_unmap,
 	.process_element	= ocxlflash_process_element,
 	.start_context		= ocxlflash_start_context,
+	.stop_context		= ocxlflash_stop_context,
 	.set_master		= ocxlflash_set_master,
 	.get_context		= ocxlflash_get_context,
 	.dev_context_init	= ocxlflash_dev_context_init,
-- 
2.1.0

[PATCH v3 24/41] cxlflash: Support AFU interrupt management

[Uma Krishnan]

Add support to allocate and free AFU interrupts using the OCXL provider
services. The trigger page returned upon successful allocation will be
mapped and exposed to the cxlflash core in a future commit.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 104 ++++++++++++++++++++++++++++++++++++++++
 drivers/scsi/cxlflash/ocxl_hw.h |  10 ++++
 2 files changed, 114 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 8d21f94..75351c3 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -385,6 +385,108 @@ static ssize_t ocxlflash_read_adapter_vpd(struct pci_dev *pdev, void *buf,
 }
 
 /**
+ * free_afu_irqs() - internal service to free interrupts
+ * @ctx:	Adapter context.
+ */
+static void free_afu_irqs(struct ocxlflash_context *ctx)
+{
+	struct ocxl_hw_afu *afu = ctx->hw_afu;
+	struct device *dev = afu->dev;
+	int i;
+
+	if (!ctx->irqs) {
+		dev_err(dev, "%s: Interrupts not allocated\n", __func__);
+		return;
+	}
+
+	for (i = ctx->num_irqs; i >= 0; i--)
+		ocxl_link_free_irq(afu->link_token, ctx->irqs[i].hwirq);
+
+	kfree(ctx->irqs);
+	ctx->irqs = NULL;
+}
+
+/**
+ * alloc_afu_irqs() - internal service to allocate interrupts
+ * @ctx:	Context associated with the request.
+ * @num:	Number of interrupts requested.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int alloc_afu_irqs(struct ocxlflash_context *ctx, int num)
+{
+	struct ocxl_hw_afu *afu = ctx->hw_afu;
+	struct device *dev = afu->dev;
+	struct ocxlflash_irqs *irqs;
+	u64 addr;
+	int rc = 0;
+	int hwirq;
+	int i;
+
+	if (ctx->irqs) {
+		dev_err(dev, "%s: Interrupts already allocated\n", __func__);
+		rc = -EEXIST;
+		goto out;
+	}
+
+	if (num > OCXL_MAX_IRQS) {
+		dev_err(dev, "%s: Too many interrupts num=%d\n", __func__, num);
+		rc = -EINVAL;
+		goto out;
+	}
+
+	irqs = kcalloc(num, sizeof(*irqs), GFP_KERNEL);
+	if (unlikely(!irqs)) {
+		dev_err(dev, "%s: Context irqs allocation failed\n", __func__);
+		rc = -ENOMEM;
+		goto out;
+	}
+
+	for (i = 0; i < num; i++) {
+		rc = ocxl_link_irq_alloc(afu->link_token, &hwirq, &addr);
+		if (unlikely(rc)) {
+			dev_err(dev, "%s: ocxl_link_irq_alloc failed rc=%d\n",
+				__func__, rc);
+			goto err;
+		}
+
+		irqs[i].hwirq = hwirq;
+		irqs[i].ptrig = addr;
+	}
+
+	ctx->irqs = irqs;
+	ctx->num_irqs = num;
+out:
+	return rc;
+err:
+	for (i = i-1; i >= 0; i--)
+		ocxl_link_free_irq(afu->link_token, irqs[i].hwirq);
+	kfree(irqs);
+	goto out;
+}
+
+/**
+ * ocxlflash_allocate_afu_irqs() - allocates the requested number of interrupts
+ * @ctx_cookie:	Context associated with the request.
+ * @num:	Number of interrupts requested.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_allocate_afu_irqs(void *ctx_cookie, int num)
+{
+	return alloc_afu_irqs(ctx_cookie, num);
+}
+
+/**
+ * ocxlflash_free_afu_irqs() - frees the interrupts of an adapter context
+ * @ctx_cookie:	Adapter context.
+ */
+static void ocxlflash_free_afu_irqs(void *ctx_cookie)
+{
+	free_afu_irqs(ctx_cookie);
+}
+
+/**
  * ocxlflash_unconfig_afu() - unconfigure the AFU
  * @afu: AFU associated with the host.
  */
@@ -750,6 +852,8 @@ const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.release_context	= ocxlflash_release_context,
 	.perst_reloads_same_image = ocxlflash_perst_reloads_same_image,
 	.read_adapter_vpd	= ocxlflash_read_adapter_vpd,
+	.allocate_afu_irqs	= ocxlflash_allocate_afu_irqs,
+	.free_afu_irqs		= ocxlflash_free_afu_irqs,
 	.create_afu		= ocxlflash_create_afu,
 	.destroy_afu		= ocxlflash_destroy_afu,
 	.get_fd			= ocxlflash_get_fd,
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index 09fa94c..85b3fad 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -12,6 +12,13 @@
  * 2 of the License, or (at your option) any later version.
  */
 
+#define OCXL_MAX_IRQS	4	/* Max interrupts per process */
+
+struct ocxlflash_irqs {
+	int hwirq;
+	u64 ptrig;
+};
+
 /* OCXL hardware AFU associated with the host */
 struct ocxl_hw_afu {
 	struct ocxlflash_context *ocxl_ctx; /* Host context */
@@ -45,4 +52,7 @@ struct ocxlflash_context {
 
 	phys_addr_t psn_phys;		/* Process mapping */
 	u64 psn_size;			/* Process mapping size */
+
+	struct ocxlflash_irqs *irqs;	/* Pointer to array of structures */
+	int num_irqs;			/* Number of interrupts */
 };
-- 
2.1.0

[PATCH v3 24/41] cxlflash: Support AFU interrupt management

[Uma Krishnan]

Add support to allocate and free AFU interrupts using the OCXL provider
services. The trigger page returned upon successful allocation will be
mapped and exposed to the cxlflash core in a future commit.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 104 ++++++++++++++++++++++++++++++++++++++++
 drivers/scsi/cxlflash/ocxl_hw.h |  10 ++++
 2 files changed, 114 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 8d21f94..75351c3 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -385,6 +385,108 @@ static ssize_t ocxlflash_read_adapter_vpd(struct pci_dev *pdev, void *buf,
 }
 
 /**
+ * free_afu_irqs() - internal service to free interrupts
+ * @ctx:	Adapter context.
+ */
+static void free_afu_irqs(struct ocxlflash_context *ctx)
+{
+	struct ocxl_hw_afu *afu = ctx->hw_afu;
+	struct device *dev = afu->dev;
+	int i;
+
+	if (!ctx->irqs) {
+		dev_err(dev, "%s: Interrupts not allocated\n", __func__);
+		return;
+	}
+
+	for (i = ctx->num_irqs; i >= 0; i--)
+		ocxl_link_free_irq(afu->link_token, ctx->irqs[i].hwirq);
+
+	kfree(ctx->irqs);
+	ctx->irqs = NULL;
+}
+
+/**
+ * alloc_afu_irqs() - internal service to allocate interrupts
+ * @ctx:	Context associated with the request.
+ * @num:	Number of interrupts requested.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int alloc_afu_irqs(struct ocxlflash_context *ctx, int num)
+{
+	struct ocxl_hw_afu *afu = ctx->hw_afu;
+	struct device *dev = afu->dev;
+	struct ocxlflash_irqs *irqs;
+	u64 addr;
+	int rc = 0;
+	int hwirq;
+	int i;
+
+	if (ctx->irqs) {
+		dev_err(dev, "%s: Interrupts already allocated\n", __func__);
+		rc = -EEXIST;
+		goto out;
+	}
+
+	if (num > OCXL_MAX_IRQS) {
+		dev_err(dev, "%s: Too many interrupts num=%d\n", __func__, num);
+		rc = -EINVAL;
+		goto out;
+	}
+
+	irqs = kcalloc(num, sizeof(*irqs), GFP_KERNEL);
+	if (unlikely(!irqs)) {
+		dev_err(dev, "%s: Context irqs allocation failed\n", __func__);
+		rc = -ENOMEM;
+		goto out;
+	}
+
+	for (i = 0; i < num; i++) {
+		rc = ocxl_link_irq_alloc(afu->link_token, &hwirq, &addr);
+		if (unlikely(rc)) {
+			dev_err(dev, "%s: ocxl_link_irq_alloc failed rc=%d\n",
+				__func__, rc);
+			goto err;
+		}
+
+		irqs[i].hwirq = hwirq;
+		irqs[i].ptrig = addr;
+	}
+
+	ctx->irqs = irqs;
+	ctx->num_irqs = num;
+out:
+	return rc;
+err:
+	for (i = i-1; i >= 0; i--)
+		ocxl_link_free_irq(afu->link_token, irqs[i].hwirq);
+	kfree(irqs);
+	goto out;
+}
+
+/**
+ * ocxlflash_allocate_afu_irqs() - allocates the requested number of interrupts
+ * @ctx_cookie:	Context associated with the request.
+ * @num:	Number of interrupts requested.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_allocate_afu_irqs(void *ctx_cookie, int num)
+{
+	return alloc_afu_irqs(ctx_cookie, num);
+}
+
+/**
+ * ocxlflash_free_afu_irqs() - frees the interrupts of an adapter context
+ * @ctx_cookie:	Adapter context.
+ */
+static void ocxlflash_free_afu_irqs(void *ctx_cookie)
+{
+	free_afu_irqs(ctx_cookie);
+}
+
+/**
  * ocxlflash_unconfig_afu() - unconfigure the AFU
  * @afu: AFU associated with the host.
  */
@@ -750,6 +852,8 @@ const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.release_context	= ocxlflash_release_context,
 	.perst_reloads_same_image = ocxlflash_perst_reloads_same_image,
 	.read_adapter_vpd	= ocxlflash_read_adapter_vpd,
+	.allocate_afu_irqs	= ocxlflash_allocate_afu_irqs,
+	.free_afu_irqs		= ocxlflash_free_afu_irqs,
 	.create_afu		= ocxlflash_create_afu,
 	.destroy_afu		= ocxlflash_destroy_afu,
 	.get_fd			= ocxlflash_get_fd,
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index 09fa94c..85b3fad 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -12,6 +12,13 @@
  * 2 of the License, or (at your option) any later version.
  */
 
+#define OCXL_MAX_IRQS	4	/* Max interrupts per process */
+
+struct ocxlflash_irqs {
+	int hwirq;
+	u64 ptrig;
+};
+
 /* OCXL hardware AFU associated with the host */
 struct ocxl_hw_afu {
 	struct ocxlflash_context *ocxl_ctx; /* Host context */
@@ -45,4 +52,7 @@ struct ocxlflash_context {
 
 	phys_addr_t psn_phys;		/* Process mapping */
 	u64 psn_size;			/* Process mapping size */
+
+	struct ocxlflash_irqs *irqs;	/* Pointer to array of structures */
+	int num_irqs;			/* Number of interrupts */
 };
-- 
2.1.0

[PATCH v3 25/41] cxlflash: Support AFU interrupt mapping and registration

[Uma Krishnan]

Add support to map and unmap the irq space and manage irq registrations
with the kernel for each allocated AFU interrupt. Also support mapping
the physical trigger page to obtain an effective address that will be
provided to the cxlflash core in a future commit.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 120 ++++++++++++++++++++++++++++++++++++++++
 drivers/scsi/cxlflash/ocxl_hw.h |   2 +
 2 files changed, 122 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 75351c3..c53405e 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -186,6 +186,124 @@ static int ocxlflash_process_element(void *ctx_cookie)
 }
 
 /**
+ * afu_map_irq() - map the interrupt of the adapter context
+ * @flags:	Flags.
+ * @ctx:	Adapter context.
+ * @num:	Per-context AFU interrupt number.
+ * @handler:	Interrupt handler to register.
+ * @cookie:	Interrupt handler private data.
+ * @name:	Name of the interrupt.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int afu_map_irq(u64 flags, struct ocxlflash_context *ctx, int num,
+		       irq_handler_t handler, void *cookie, char *name)
+{
+	struct ocxl_hw_afu *afu = ctx->hw_afu;
+	struct device *dev = afu->dev;
+	struct ocxlflash_irqs *irq;
+	void __iomem *vtrig;
+	u32 virq;
+	int rc = 0;
+
+	if (num < 0 || num >= ctx->num_irqs) {
+		dev_err(dev, "%s: Interrupt %d not allocated\n", __func__, num);
+		rc = -ENOENT;
+		goto out;
+	}
+
+	irq = &ctx->irqs[num];
+	virq = irq_create_mapping(NULL, irq->hwirq);
+	if (unlikely(!virq)) {
+		dev_err(dev, "%s: irq_create_mapping failed\n", __func__);
+		rc = -ENOMEM;
+		goto out;
+	}
+
+	rc = request_irq(virq, handler, 0, name, cookie);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: request_irq failed rc=%d\n", __func__, rc);
+		goto err1;
+	}
+
+	vtrig = ioremap(irq->ptrig, PAGE_SIZE);
+	if (unlikely(!vtrig)) {
+		dev_err(dev, "%s: Trigger page mapping failed\n", __func__);
+		rc = -ENOMEM;
+		goto err2;
+	}
+
+	irq->virq = virq;
+	irq->vtrig = vtrig;
+out:
+	return rc;
+err2:
+	free_irq(virq, cookie);
+err1:
+	irq_dispose_mapping(virq);
+	goto out;
+}
+
+/**
+ * ocxlflash_map_afu_irq() - map the interrupt of the adapter context
+ * @ctx_cookie:	Adapter context.
+ * @num:	Per-context AFU interrupt number.
+ * @handler:	Interrupt handler to register.
+ * @cookie:	Interrupt handler private data.
+ * @name:	Name of the interrupt.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_map_afu_irq(void *ctx_cookie, int num,
+				 irq_handler_t handler, void *cookie,
+				 char *name)
+{
+	return afu_map_irq(0, ctx_cookie, num, handler, cookie, name);
+}
+
+/**
+ * afu_unmap_irq() - unmap the interrupt
+ * @flags:	Flags.
+ * @ctx:	Adapter context.
+ * @num:	Per-context AFU interrupt number.
+ * @cookie:	Interrupt handler private data.
+ */
+static void afu_unmap_irq(u64 flags, struct ocxlflash_context *ctx, int num,
+			  void *cookie)
+{
+	struct ocxl_hw_afu *afu = ctx->hw_afu;
+	struct device *dev = afu->dev;
+	struct ocxlflash_irqs *irq;
+
+	if (num < 0 || num >= ctx->num_irqs) {
+		dev_err(dev, "%s: Interrupt %d not allocated\n", __func__, num);
+		return;
+	}
+
+	irq = &ctx->irqs[num];
+	if (irq->vtrig)
+		iounmap(irq->vtrig);
+
+	if (irq_find_mapping(NULL, irq->hwirq)) {
+		free_irq(irq->virq, cookie);
+		irq_dispose_mapping(irq->virq);
+	}
+
+	memset(irq, 0, sizeof(*irq));
+}
+
+/**
+ * ocxlflash_unmap_afu_irq() - unmap the interrupt
+ * @ctx_cookie:	Adapter context.
+ * @num:	Per-context AFU interrupt number.
+ * @cookie:	Interrupt handler private data.
+ */
+static void ocxlflash_unmap_afu_irq(void *ctx_cookie, int num, void *cookie)
+{
+	return afu_unmap_irq(0, ctx_cookie, num, cookie);
+}
+
+/**
  * start_context() - local routine to start a context
  * @ctx:	Adapter context to be started.
  *
@@ -844,6 +962,8 @@ const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.psa_map		= ocxlflash_psa_map,
 	.psa_unmap		= ocxlflash_psa_unmap,
 	.process_element	= ocxlflash_process_element,
+	.map_afu_irq		= ocxlflash_map_afu_irq,
+	.unmap_afu_irq		= ocxlflash_unmap_afu_irq,
 	.start_context		= ocxlflash_start_context,
 	.stop_context		= ocxlflash_stop_context,
 	.set_master		= ocxlflash_set_master,
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index 85b3fad..9011af0 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -16,7 +16,9 @@
 
 struct ocxlflash_irqs {
 	int hwirq;
+	u32 virq;
 	u64 ptrig;
+	void __iomem *vtrig;
 };
 
 /* OCXL hardware AFU associated with the host */
-- 
2.1.0

[PATCH v3 25/41] cxlflash: Support AFU interrupt mapping and registration

[Uma Krishnan]

Add support to map and unmap the irq space and manage irq registrations
with the kernel for each allocated AFU interrupt. Also support mapping
the physical trigger page to obtain an effective address that will be
provided to the cxlflash core in a future commit.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 120 ++++++++++++++++++++++++++++++++++++++++
 drivers/scsi/cxlflash/ocxl_hw.h |   2 +
 2 files changed, 122 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 75351c3..c53405e 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -186,6 +186,124 @@ static int ocxlflash_process_element(void *ctx_cookie)
 }
 
 /**
+ * afu_map_irq() - map the interrupt of the adapter context
+ * @flags:	Flags.
+ * @ctx:	Adapter context.
+ * @num:	Per-context AFU interrupt number.
+ * @handler:	Interrupt handler to register.
+ * @cookie:	Interrupt handler private data.
+ * @name:	Name of the interrupt.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int afu_map_irq(u64 flags, struct ocxlflash_context *ctx, int num,
+		       irq_handler_t handler, void *cookie, char *name)
+{
+	struct ocxl_hw_afu *afu = ctx->hw_afu;
+	struct device *dev = afu->dev;
+	struct ocxlflash_irqs *irq;
+	void __iomem *vtrig;
+	u32 virq;
+	int rc = 0;
+
+	if (num < 0 || num >= ctx->num_irqs) {
+		dev_err(dev, "%s: Interrupt %d not allocated\n", __func__, num);
+		rc = -ENOENT;
+		goto out;
+	}
+
+	irq = &ctx->irqs[num];
+	virq = irq_create_mapping(NULL, irq->hwirq);
+	if (unlikely(!virq)) {
+		dev_err(dev, "%s: irq_create_mapping failed\n", __func__);
+		rc = -ENOMEM;
+		goto out;
+	}
+
+	rc = request_irq(virq, handler, 0, name, cookie);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: request_irq failed rc=%d\n", __func__, rc);
+		goto err1;
+	}
+
+	vtrig = ioremap(irq->ptrig, PAGE_SIZE);
+	if (unlikely(!vtrig)) {
+		dev_err(dev, "%s: Trigger page mapping failed\n", __func__);
+		rc = -ENOMEM;
+		goto err2;
+	}
+
+	irq->virq = virq;
+	irq->vtrig = vtrig;
+out:
+	return rc;
+err2:
+	free_irq(virq, cookie);
+err1:
+	irq_dispose_mapping(virq);
+	goto out;
+}
+
+/**
+ * ocxlflash_map_afu_irq() - map the interrupt of the adapter context
+ * @ctx_cookie:	Adapter context.
+ * @num:	Per-context AFU interrupt number.
+ * @handler:	Interrupt handler to register.
+ * @cookie:	Interrupt handler private data.
+ * @name:	Name of the interrupt.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_map_afu_irq(void *ctx_cookie, int num,
+				 irq_handler_t handler, void *cookie,
+				 char *name)
+{
+	return afu_map_irq(0, ctx_cookie, num, handler, cookie, name);
+}
+
+/**
+ * afu_unmap_irq() - unmap the interrupt
+ * @flags:	Flags.
+ * @ctx:	Adapter context.
+ * @num:	Per-context AFU interrupt number.
+ * @cookie:	Interrupt handler private data.
+ */
+static void afu_unmap_irq(u64 flags, struct ocxlflash_context *ctx, int num,
+			  void *cookie)
+{
+	struct ocxl_hw_afu *afu = ctx->hw_afu;
+	struct device *dev = afu->dev;
+	struct ocxlflash_irqs *irq;
+
+	if (num < 0 || num >= ctx->num_irqs) {
+		dev_err(dev, "%s: Interrupt %d not allocated\n", __func__, num);
+		return;
+	}
+
+	irq = &ctx->irqs[num];
+	if (irq->vtrig)
+		iounmap(irq->vtrig);
+
+	if (irq_find_mapping(NULL, irq->hwirq)) {
+		free_irq(irq->virq, cookie);
+		irq_dispose_mapping(irq->virq);
+	}
+
+	memset(irq, 0, sizeof(*irq));
+}
+
+/**
+ * ocxlflash_unmap_afu_irq() - unmap the interrupt
+ * @ctx_cookie:	Adapter context.
+ * @num:	Per-context AFU interrupt number.
+ * @cookie:	Interrupt handler private data.
+ */
+static void ocxlflash_unmap_afu_irq(void *ctx_cookie, int num, void *cookie)
+{
+	return afu_unmap_irq(0, ctx_cookie, num, cookie);
+}
+
+/**
  * start_context() - local routine to start a context
  * @ctx:	Adapter context to be started.
  *
@@ -844,6 +962,8 @@ const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.psa_map		= ocxlflash_psa_map,
 	.psa_unmap		= ocxlflash_psa_unmap,
 	.process_element	= ocxlflash_process_element,
+	.map_afu_irq		= ocxlflash_map_afu_irq,
+	.unmap_afu_irq		= ocxlflash_unmap_afu_irq,
 	.start_context		= ocxlflash_start_context,
 	.stop_context		= ocxlflash_stop_context,
 	.set_master		= ocxlflash_set_master,
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index 85b3fad..9011af0 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -16,7 +16,9 @@
 
 struct ocxlflash_irqs {
 	int hwirq;
+	u32 virq;
 	u64 ptrig;
+	void __iomem *vtrig;
 };
 
 /* OCXL hardware AFU associated with the host */
-- 
2.1.0

[PATCH v3 26/41] cxlflash: Support starting user contexts

[Uma Krishnan]

User contexts request interrupts and are started using the "start work"
interface. Populate the start_work() fop to allocate and map interrupts
before starting the user context. As part of starting the context, update
the user process identification logic to properly derive the data required
by the SPA. Also, introduce a skeleton interrupt handler using a bitmap,
flag, and spinlock to track interrupts. This handler will be expanded in
future commits.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 99 ++++++++++++++++++++++++++++++++++++++++-
 drivers/scsi/cxlflash/ocxl_hw.h |  3 ++
 2 files changed, 100 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index c53405e..576a39e 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -318,7 +318,9 @@ static int start_context(struct ocxlflash_context *ctx)
 	void *link_token = afu->link_token;
 	struct device *dev = afu->dev;
 	bool master = ctx->master;
+	struct mm_struct *mm;
 	int rc = 0;
+	u32 pid;
 
 	if (master) {
 		ctx->psn_size = acfg->global_mmio_size;
@@ -328,9 +330,16 @@ static int start_context(struct ocxlflash_context *ctx)
 		ctx->psn_phys = afu->ppmmio_phys + (ctx->pe * ctx->psn_size);
 	}
 
+	/* pid and mm not set for master contexts */
+	if (master) {
+		pid = 0;
+		mm = NULL;
+	} else {
+		pid = current->mm->context.id;
+		mm = current->mm;
+	}
 
-	/* pid, tid, amr and mm are zeroes/NULL for a kernel context */
-	rc = ocxl_link_add_pe(link_token, ctx->pe, 0, 0, 0, NULL, NULL, NULL);
+	rc = ocxl_link_add_pe(link_token, ctx->pe, pid, 0, 0, mm, NULL, NULL);
 	if (unlikely(rc)) {
 		dev_err(dev, "%s: ocxl_link_add_pe failed rc=%d\n",
 			__func__, rc);
@@ -442,10 +451,14 @@ static void *ocxlflash_dev_context_init(struct pci_dev *pdev, void *afu_cookie)
 		goto err2;
 	}
 
+	spin_lock_init(&ctx->slock);
+
 	ctx->pe = rc;
 	ctx->master = false;
 	ctx->mapping = NULL;
 	ctx->hw_afu = afu;
+	ctx->irq_bitmap = 0;
+	ctx->pending_irq = false;
 out:
 	return ctx;
 err2:
@@ -956,6 +969,87 @@ static void *ocxlflash_fops_get_context(struct file *file)
 	return file->private_data;
 }
 
+/**
+ * ocxlflash_afu_irq() - interrupt handler for user contexts
+ * @irq:	Interrupt number.
+ * @data:	Private data provided at interrupt registration, the context.
+ *
+ * Return: Always return IRQ_HANDLED.
+ */
+static irqreturn_t ocxlflash_afu_irq(int irq, void *data)
+{
+	struct ocxlflash_context *ctx = data;
+	struct device *dev = ctx->hw_afu->dev;
+	int i;
+
+	dev_dbg(dev, "%s: Interrupt raised for pe %i virq %i\n",
+		__func__, ctx->pe, irq);
+
+	for (i = 0; i < ctx->num_irqs; i++) {
+		if (ctx->irqs[i].virq == irq)
+			break;
+	}
+	if (unlikely(i >= ctx->num_irqs)) {
+		dev_err(dev, "%s: Received AFU IRQ out of range\n", __func__);
+		goto out;
+	}
+
+	spin_lock(&ctx->slock);
+	set_bit(i - 1, &ctx->irq_bitmap);
+	ctx->pending_irq = true;
+	spin_unlock(&ctx->slock);
+out:
+	return IRQ_HANDLED;
+}
+
+/**
+ * ocxlflash_start_work() - start a user context
+ * @ctx_cookie:	Context to be started.
+ * @num_irqs:	Number of interrupts requested.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_start_work(void *ctx_cookie, u64 num_irqs)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+	struct ocxl_hw_afu *afu = ctx->hw_afu;
+	struct device *dev = afu->dev;
+	char *name;
+	int rc = 0;
+	int i;
+
+	rc = alloc_afu_irqs(ctx, num_irqs);
+	if (unlikely(rc < 0)) {
+		dev_err(dev, "%s: alloc_afu_irqs failed rc=%d\n", __func__, rc);
+		goto out;
+	}
+
+	for (i = 0; i < num_irqs; i++) {
+		name = kasprintf(GFP_KERNEL, "ocxlflash-%s-pe%i-%i",
+				 dev_name(dev), ctx->pe, i);
+		rc = afu_map_irq(0, ctx, i, ocxlflash_afu_irq, ctx, name);
+		kfree(name);
+		if (unlikely(rc < 0)) {
+			dev_err(dev, "%s: afu_map_irq failed rc=%d\n",
+				__func__, rc);
+			goto err;
+		}
+	}
+
+	rc = start_context(ctx);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: start_context failed rc=%d\n", __func__, rc);
+		goto err;
+	}
+out:
+	return rc;
+err:
+	for (i = i-1; i >= 0; i--)
+		afu_unmap_irq(0, ctx, i, ctx);
+	free_afu_irqs(ctx);
+	goto out;
+}
+
 /* Backend ops to ocxlflash services */
 const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.module			= THIS_MODULE,
@@ -978,4 +1072,5 @@ const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.destroy_afu		= ocxlflash_destroy_afu,
 	.get_fd			= ocxlflash_get_fd,
 	.fops_get_context	= ocxlflash_fops_get_context,
+	.start_work		= ocxlflash_start_work,
 };
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index 9011af0..2eb5390 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -55,6 +55,9 @@ struct ocxlflash_context {
 	phys_addr_t psn_phys;		/* Process mapping */
 	u64 psn_size;			/* Process mapping size */
 
+	spinlock_t slock;		/* Protects irq/fault/event updates */
 	struct ocxlflash_irqs *irqs;	/* Pointer to array of structures */
 	int num_irqs;			/* Number of interrupts */
+	bool pending_irq;		/* Pending interrupt on the context */
+	ulong irq_bitmap;		/* Bits indicating pending irq num */
 };
-- 
2.1.0

[PATCH v3 26/41] cxlflash: Support starting user contexts

[Uma Krishnan]

User contexts request interrupts and are started using the "start work"
interface. Populate the start_work() fop to allocate and map interrupts
before starting the user context. As part of starting the context, update
the user process identification logic to properly derive the data required
by the SPA. Also, introduce a skeleton interrupt handler using a bitmap,
flag, and spinlock to track interrupts. This handler will be expanded in
future commits.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 99 ++++++++++++++++++++++++++++++++++++++++-
 drivers/scsi/cxlflash/ocxl_hw.h |  3 ++
 2 files changed, 100 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index c53405e..576a39e 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -318,7 +318,9 @@ static int start_context(struct ocxlflash_context *ctx)
 	void *link_token = afu->link_token;
 	struct device *dev = afu->dev;
 	bool master = ctx->master;
+	struct mm_struct *mm;
 	int rc = 0;
+	u32 pid;
 
 	if (master) {
 		ctx->psn_size = acfg->global_mmio_size;
@@ -328,9 +330,16 @@ static int start_context(struct ocxlflash_context *ctx)
 		ctx->psn_phys = afu->ppmmio_phys + (ctx->pe * ctx->psn_size);
 	}
 
+	/* pid and mm not set for master contexts */
+	if (master) {
+		pid = 0;
+		mm = NULL;
+	} else {
+		pid = current->mm->context.id;
+		mm = current->mm;
+	}
 
-	/* pid, tid, amr and mm are zeroes/NULL for a kernel context */
-	rc = ocxl_link_add_pe(link_token, ctx->pe, 0, 0, 0, NULL, NULL, NULL);
+	rc = ocxl_link_add_pe(link_token, ctx->pe, pid, 0, 0, mm, NULL, NULL);
 	if (unlikely(rc)) {
 		dev_err(dev, "%s: ocxl_link_add_pe failed rc=%d\n",
 			__func__, rc);
@@ -442,10 +451,14 @@ static void *ocxlflash_dev_context_init(struct pci_dev *pdev, void *afu_cookie)
 		goto err2;
 	}
 
+	spin_lock_init(&ctx->slock);
+
 	ctx->pe = rc;
 	ctx->master = false;
 	ctx->mapping = NULL;
 	ctx->hw_afu = afu;
+	ctx->irq_bitmap = 0;
+	ctx->pending_irq = false;
 out:
 	return ctx;
 err2:
@@ -956,6 +969,87 @@ static void *ocxlflash_fops_get_context(struct file *file)
 	return file->private_data;
 }
 
+/**
+ * ocxlflash_afu_irq() - interrupt handler for user contexts
+ * @irq:	Interrupt number.
+ * @data:	Private data provided at interrupt registration, the context.
+ *
+ * Return: Always return IRQ_HANDLED.
+ */
+static irqreturn_t ocxlflash_afu_irq(int irq, void *data)
+{
+	struct ocxlflash_context *ctx = data;
+	struct device *dev = ctx->hw_afu->dev;
+	int i;
+
+	dev_dbg(dev, "%s: Interrupt raised for pe %i virq %i\n",
+		__func__, ctx->pe, irq);
+
+	for (i = 0; i < ctx->num_irqs; i++) {
+		if (ctx->irqs[i].virq == irq)
+			break;
+	}
+	if (unlikely(i >= ctx->num_irqs)) {
+		dev_err(dev, "%s: Received AFU IRQ out of range\n", __func__);
+		goto out;
+	}
+
+	spin_lock(&ctx->slock);
+	set_bit(i - 1, &ctx->irq_bitmap);
+	ctx->pending_irq = true;
+	spin_unlock(&ctx->slock);
+out:
+	return IRQ_HANDLED;
+}
+
+/**
+ * ocxlflash_start_work() - start a user context
+ * @ctx_cookie:	Context to be started.
+ * @num_irqs:	Number of interrupts requested.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_start_work(void *ctx_cookie, u64 num_irqs)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+	struct ocxl_hw_afu *afu = ctx->hw_afu;
+	struct device *dev = afu->dev;
+	char *name;
+	int rc = 0;
+	int i;
+
+	rc = alloc_afu_irqs(ctx, num_irqs);
+	if (unlikely(rc < 0)) {
+		dev_err(dev, "%s: alloc_afu_irqs failed rc=%d\n", __func__, rc);
+		goto out;
+	}
+
+	for (i = 0; i < num_irqs; i++) {
+		name = kasprintf(GFP_KERNEL, "ocxlflash-%s-pe%i-%i",
+				 dev_name(dev), ctx->pe, i);
+		rc = afu_map_irq(0, ctx, i, ocxlflash_afu_irq, ctx, name);
+		kfree(name);
+		if (unlikely(rc < 0)) {
+			dev_err(dev, "%s: afu_map_irq failed rc=%d\n",
+				__func__, rc);
+			goto err;
+		}
+	}
+
+	rc = start_context(ctx);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: start_context failed rc=%d\n", __func__, rc);
+		goto err;
+	}
+out:
+	return rc;
+err:
+	for (i = i-1; i >= 0; i--)
+		afu_unmap_irq(0, ctx, i, ctx);
+	free_afu_irqs(ctx);
+	goto out;
+}
+
 /* Backend ops to ocxlflash services */
 const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.module			= THIS_MODULE,
@@ -978,4 +1072,5 @@ const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.destroy_afu		= ocxlflash_destroy_afu,
 	.get_fd			= ocxlflash_get_fd,
 	.fops_get_context	= ocxlflash_fops_get_context,
+	.start_work		= ocxlflash_start_work,
 };
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index 9011af0..2eb5390 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -55,6 +55,9 @@ struct ocxlflash_context {
 	phys_addr_t psn_phys;		/* Process mapping */
 	u64 psn_size;			/* Process mapping size */
 
+	spinlock_t slock;		/* Protects irq/fault/event updates */
 	struct ocxlflash_irqs *irqs;	/* Pointer to array of structures */
 	int num_irqs;			/* Number of interrupts */
+	bool pending_irq;		/* Pending interrupt on the context */
+	ulong irq_bitmap;		/* Bits indicating pending irq num */
 };
-- 
2.1.0

[PATCH v3 27/41] cxlflash: Support adapter context polling

[Uma Krishnan]

The cxlflash userspace API requires that users be able to poll the adapter
context for any pending events or interrupts from the AFU. Support polling
on various events by implementing the AFU poll fop using a waitqueue.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 57 +++++++++++++++++++++++++++++++++++++++--
 drivers/scsi/cxlflash/ocxl_hw.h |  2 ++
 2 files changed, 57 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 576a39e..655377d 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -16,6 +16,7 @@
 #include <linux/idr.h>
 #include <linux/module.h>
 #include <linux/mount.h>
+#include <linux/poll.h>
 
 #include <misc/ocxl.h>
 
@@ -452,6 +453,7 @@ static void *ocxlflash_dev_context_init(struct pci_dev *pdev, void *afu_cookie)
 	}
 
 	spin_lock_init(&ctx->slock);
+	init_waitqueue_head(&ctx->wq);
 
 	ctx->pe = rc;
 	ctx->master = false;
@@ -892,10 +894,57 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
 	goto out;
 }
 
+/**
+ * ctx_event_pending() - check for any event pending on the context
+ * @ctx:	Context to be checked.
+ *
+ * Return: true if there is an event pending, false if none pending
+ */
+static inline bool ctx_event_pending(struct ocxlflash_context *ctx)
+{
+	if (ctx->pending_irq)
+		return true;
+
+	return false;
+}
+
+/**
+ * afu_poll() - poll the AFU for events on the context
+ * @file:	File associated with the adapter context.
+ * @poll:	Poll structure from the user.
+ *
+ * Return: poll mask
+ */
+static unsigned int afu_poll(struct file *file, struct poll_table_struct *poll)
+{
+	struct ocxlflash_context *ctx = file->private_data;
+	struct device *dev = ctx->hw_afu->dev;
+	ulong lock_flags;
+	int mask = 0;
+
+	poll_wait(file, &ctx->wq, poll);
+
+	spin_lock_irqsave(&ctx->slock, lock_flags);
+	if (ctx_event_pending(ctx))
+		mask |= POLLIN | POLLRDNORM;
+	else
+		mask |= POLLERR;
+	spin_unlock_irqrestore(&ctx->slock, lock_flags);
+
+	dev_dbg(dev, "%s: Poll wait completed for pe %i mask %i\n",
+		__func__, ctx->pe, mask);
+
+	return mask;
+}
+
 static const struct file_operations ocxl_afu_fops = {
 	.owner		= THIS_MODULE,
+	.poll		= afu_poll,
 };
 
+#define PATCH_FOPS(NAME)						\
+	do { if (!fops->NAME) fops->NAME = ocxl_afu_fops.NAME; } while (0)
+
 /**
  * ocxlflash_get_fd() - get file descriptor for an adapter context
  * @ctx_cookie:	Adapter context.
@@ -933,8 +982,10 @@ static struct file *ocxlflash_get_fd(void *ctx_cookie,
 	}
 	fdtmp = rc;
 
-	/* Use default ops if there is no fops */
-	if (!fops)
+	/* Patch the file ops that are not defined */
+	if (fops) {
+		PATCH_FOPS(poll);
+	} else /* Use default ops */
 		fops = (struct file_operations *)&ocxl_afu_fops;
 
 	name = kasprintf(GFP_KERNEL, "ocxlflash:%d", ctx->pe);
@@ -998,6 +1049,8 @@ static irqreturn_t ocxlflash_afu_irq(int irq, void *data)
 	set_bit(i - 1, &ctx->irq_bitmap);
 	ctx->pending_irq = true;
 	spin_unlock(&ctx->slock);
+
+	wake_up_all(&ctx->wq);
 out:
 	return IRQ_HANDLED;
 }
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index 2eb5390..acd2801 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -56,6 +56,8 @@ struct ocxlflash_context {
 	u64 psn_size;			/* Process mapping size */
 
 	spinlock_t slock;		/* Protects irq/fault/event updates */
+	wait_queue_head_t wq;		/* Wait queue for poll and interrupts */
+
 	struct ocxlflash_irqs *irqs;	/* Pointer to array of structures */
 	int num_irqs;			/* Number of interrupts */
 	bool pending_irq;		/* Pending interrupt on the context */
-- 
2.1.0

[PATCH v3 27/41] cxlflash: Support adapter context polling

[Uma Krishnan]

The cxlflash userspace API requires that users be able to poll the adapter
context for any pending events or interrupts from the AFU. Support polling
on various events by implementing the AFU poll fop using a waitqueue.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 57 +++++++++++++++++++++++++++++++++++++++--
 drivers/scsi/cxlflash/ocxl_hw.h |  2 ++
 2 files changed, 57 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 576a39e..655377d 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -16,6 +16,7 @@
 #include <linux/idr.h>
 #include <linux/module.h>
 #include <linux/mount.h>
+#include <linux/poll.h>
 
 #include <misc/ocxl.h>
 
@@ -452,6 +453,7 @@ static void *ocxlflash_dev_context_init(struct pci_dev *pdev, void *afu_cookie)
 	}
 
 	spin_lock_init(&ctx->slock);
+	init_waitqueue_head(&ctx->wq);
 
 	ctx->pe = rc;
 	ctx->master = false;
@@ -892,10 +894,57 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
 	goto out;
 }
 
+/**
+ * ctx_event_pending() - check for any event pending on the context
+ * @ctx:	Context to be checked.
+ *
+ * Return: true if there is an event pending, false if none pending
+ */
+static inline bool ctx_event_pending(struct ocxlflash_context *ctx)
+{
+	if (ctx->pending_irq)
+		return true;
+
+	return false;
+}
+
+/**
+ * afu_poll() - poll the AFU for events on the context
+ * @file:	File associated with the adapter context.
+ * @poll:	Poll structure from the user.
+ *
+ * Return: poll mask
+ */
+static unsigned int afu_poll(struct file *file, struct poll_table_struct *poll)
+{
+	struct ocxlflash_context *ctx = file->private_data;
+	struct device *dev = ctx->hw_afu->dev;
+	ulong lock_flags;
+	int mask = 0;
+
+	poll_wait(file, &ctx->wq, poll);
+
+	spin_lock_irqsave(&ctx->slock, lock_flags);
+	if (ctx_event_pending(ctx))
+		mask |= POLLIN | POLLRDNORM;
+	else
+		mask |= POLLERR;
+	spin_unlock_irqrestore(&ctx->slock, lock_flags);
+
+	dev_dbg(dev, "%s: Poll wait completed for pe %i mask %i\n",
+		__func__, ctx->pe, mask);
+
+	return mask;
+}
+
 static const struct file_operations ocxl_afu_fops = {
 	.owner		= THIS_MODULE,
+	.poll		= afu_poll,
 };
 
+#define PATCH_FOPS(NAME)						\
+	do { if (!fops->NAME) fops->NAME = ocxl_afu_fops.NAME; } while (0)
+
 /**
  * ocxlflash_get_fd() - get file descriptor for an adapter context
  * @ctx_cookie:	Adapter context.
@@ -933,8 +982,10 @@ static struct file *ocxlflash_get_fd(void *ctx_cookie,
 	}
 	fdtmp = rc;
 
-	/* Use default ops if there is no fops */
-	if (!fops)
+	/* Patch the file ops that are not defined */
+	if (fops) {
+		PATCH_FOPS(poll);
+	} else /* Use default ops */
 		fops = (struct file_operations *)&ocxl_afu_fops;
 
 	name = kasprintf(GFP_KERNEL, "ocxlflash:%d", ctx->pe);
@@ -998,6 +1049,8 @@ static irqreturn_t ocxlflash_afu_irq(int irq, void *data)
 	set_bit(i - 1, &ctx->irq_bitmap);
 	ctx->pending_irq = true;
 	spin_unlock(&ctx->slock);
+
+	wake_up_all(&ctx->wq);
 out:
 	return IRQ_HANDLED;
 }
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index 2eb5390..acd2801 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -56,6 +56,8 @@ struct ocxlflash_context {
 	u64 psn_size;			/* Process mapping size */
 
 	spinlock_t slock;		/* Protects irq/fault/event updates */
+	wait_queue_head_t wq;		/* Wait queue for poll and interrupts */
+
 	struct ocxlflash_irqs *irqs;	/* Pointer to array of structures */
 	int num_irqs;			/* Number of interrupts */
 	bool pending_irq;		/* Pending interrupt on the context */
-- 
2.1.0

[PATCH v3 28/41] cxlflash: Support adapter context reading

[Uma Krishnan]

The cxlflash userspace API requires that users be able to read the adapter
context for any pending events or interrupts from the AFU. Support reading
various events by implementing the AFU read fop to copy out event data.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 94 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 94 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 655377d..f531403 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -17,9 +17,12 @@
 #include <linux/module.h>
 #include <linux/mount.h>
 #include <linux/poll.h>
+#include <linux/sched/signal.h>
 
 #include <misc/ocxl.h>
 
+#include <uapi/misc/cxl.h>
+
 #include "backend.h"
 #include "ocxl_hw.h"
 
@@ -937,9 +940,99 @@ static unsigned int afu_poll(struct file *file, struct poll_table_struct *poll)
 	return mask;
 }
 
+/**
+ * afu_read() - perform a read on the context for any event
+ * @file:	File associated with the adapter context.
+ * @buf:	Buffer to receive the data.
+ * @count:	Size of buffer (maximum bytes that can be read).
+ * @off:	Offset.
+ *
+ * Return: size of the data read on success, -errno on failure
+ */
+static ssize_t afu_read(struct file *file, char __user *buf, size_t count,
+			loff_t *off)
+{
+	struct ocxlflash_context *ctx = file->private_data;
+	struct device *dev = ctx->hw_afu->dev;
+	struct cxl_event event;
+	ulong lock_flags;
+	ssize_t esize;
+	ssize_t rc;
+	int bit;
+	DEFINE_WAIT(event_wait);
+
+	if (*off != 0) {
+		dev_err(dev, "%s: Non-zero offset not supported, off=%lld\n",
+			__func__, *off);
+		rc = -EINVAL;
+		goto out;
+	}
+
+	spin_lock_irqsave(&ctx->slock, lock_flags);
+
+	for (;;) {
+		prepare_to_wait(&ctx->wq, &event_wait, TASK_INTERRUPTIBLE);
+
+		if (ctx_event_pending(ctx))
+			break;
+
+		if (file->f_flags & O_NONBLOCK) {
+			dev_err(dev, "%s: File cannot be blocked on I/O\n",
+				__func__);
+			rc = -EAGAIN;
+			goto err;
+		}
+
+		if (signal_pending(current)) {
+			dev_err(dev, "%s: Signal pending on the process\n",
+				__func__);
+			rc = -ERESTARTSYS;
+			goto err;
+		}
+
+		spin_unlock_irqrestore(&ctx->slock, lock_flags);
+		schedule();
+		spin_lock_irqsave(&ctx->slock, lock_flags);
+	}
+
+	finish_wait(&ctx->wq, &event_wait);
+
+	memset(&event, 0, sizeof(event));
+	event.header.process_element = ctx->pe;
+	event.header.size = sizeof(struct cxl_event_header);
+	if (ctx->pending_irq) {
+		esize = sizeof(struct cxl_event_afu_interrupt);
+		event.header.size += esize;
+		event.header.type = CXL_EVENT_AFU_INTERRUPT;
+
+		bit = find_first_bit(&ctx->irq_bitmap, ctx->num_irqs);
+		clear_bit(bit, &ctx->irq_bitmap);
+		event.irq.irq = bit + 1;
+		if (bitmap_empty(&ctx->irq_bitmap, ctx->num_irqs))
+			ctx->pending_irq = false;
+	}
+
+	spin_unlock_irqrestore(&ctx->slock, lock_flags);
+
+	if (copy_to_user(buf, &event, event.header.size)) {
+		dev_err(dev, "%s: copy_to_user failed\n", __func__);
+		rc = -EFAULT;
+		goto out;
+	}
+
+	rc = event.header.size;
+out:
+	return rc;
+err:
+	finish_wait(&ctx->wq, &event_wait);
+	spin_unlock_irqrestore(&ctx->slock, lock_flags);
+	goto out;
+}
+
 static const struct file_operations ocxl_afu_fops = {
 	.owner		= THIS_MODULE,
 	.poll		= afu_poll,
+	.read		= afu_read,
 };
 
 #define PATCH_FOPS(NAME)						\
@@ -985,6 +1078,7 @@ static struct file *ocxlflash_get_fd(void *ctx_cookie,
 	/* Patch the file ops that are not defined */
 	if (fops) {
 		PATCH_FOPS(poll);
+		PATCH_FOPS(read);
 	} else /* Use default ops */
 		fops = (struct file_operations *)&ocxl_afu_fops;
 
-- 
2.1.0

[PATCH v3 28/41] cxlflash: Support adapter context reading

[Uma Krishnan]

The cxlflash userspace API requires that users be able to read the adapter
context for any pending events or interrupts from the AFU. Support reading
various events by implementing the AFU read fop to copy out event data.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 94 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 94 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 655377d..f531403 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -17,9 +17,12 @@
 #include <linux/module.h>
 #include <linux/mount.h>
 #include <linux/poll.h>
+#include <linux/sched/signal.h>
 
 #include <misc/ocxl.h>
 
+#include <uapi/misc/cxl.h>
+
 #include "backend.h"
 #include "ocxl_hw.h"
 
@@ -937,9 +940,99 @@ static unsigned int afu_poll(struct file *file, struct poll_table_struct *poll)
 	return mask;
 }
 
+/**
+ * afu_read() - perform a read on the context for any event
+ * @file:	File associated with the adapter context.
+ * @buf:	Buffer to receive the data.
+ * @count:	Size of buffer (maximum bytes that can be read).
+ * @off:	Offset.
+ *
+ * Return: size of the data read on success, -errno on failure
+ */
+static ssize_t afu_read(struct file *file, char __user *buf, size_t count,
+			loff_t *off)
+{
+	struct ocxlflash_context *ctx = file->private_data;
+	struct device *dev = ctx->hw_afu->dev;
+	struct cxl_event event;
+	ulong lock_flags;
+	ssize_t esize;
+	ssize_t rc;
+	int bit;
+	DEFINE_WAIT(event_wait);
+
+	if (*off != 0) {
+		dev_err(dev, "%s: Non-zero offset not supported, off=%lld\n",
+			__func__, *off);
+		rc = -EINVAL;
+		goto out;
+	}
+
+	spin_lock_irqsave(&ctx->slock, lock_flags);
+
+	for (;;) {
+		prepare_to_wait(&ctx->wq, &event_wait, TASK_INTERRUPTIBLE);
+
+		if (ctx_event_pending(ctx))
+			break;
+
+		if (file->f_flags & O_NONBLOCK) {
+			dev_err(dev, "%s: File cannot be blocked on I/O\n",
+				__func__);
+			rc = -EAGAIN;
+			goto err;
+		}
+
+		if (signal_pending(current)) {
+			dev_err(dev, "%s: Signal pending on the process\n",
+				__func__);
+			rc = -ERESTARTSYS;
+			goto err;
+		}
+
+		spin_unlock_irqrestore(&ctx->slock, lock_flags);
+		schedule();
+		spin_lock_irqsave(&ctx->slock, lock_flags);
+	}
+
+	finish_wait(&ctx->wq, &event_wait);
+
+	memset(&event, 0, sizeof(event));
+	event.header.process_element = ctx->pe;
+	event.header.size = sizeof(struct cxl_event_header);
+	if (ctx->pending_irq) {
+		esize = sizeof(struct cxl_event_afu_interrupt);
+		event.header.size += esize;
+		event.header.type = CXL_EVENT_AFU_INTERRUPT;
+
+		bit = find_first_bit(&ctx->irq_bitmap, ctx->num_irqs);
+		clear_bit(bit, &ctx->irq_bitmap);
+		event.irq.irq = bit + 1;
+		if (bitmap_empty(&ctx->irq_bitmap, ctx->num_irqs))
+			ctx->pending_irq = false;
+	}
+
+	spin_unlock_irqrestore(&ctx->slock, lock_flags);
+
+	if (copy_to_user(buf, &event, event.header.size)) {
+		dev_err(dev, "%s: copy_to_user failed\n", __func__);
+		rc = -EFAULT;
+		goto out;
+	}
+
+	rc = event.header.size;
+out:
+	return rc;
+err:
+	finish_wait(&ctx->wq, &event_wait);
+	spin_unlock_irqrestore(&ctx->slock, lock_flags);
+	goto out;
+}
+
 static const struct file_operations ocxl_afu_fops = {
 	.owner		= THIS_MODULE,
 	.poll		= afu_poll,
+	.read		= afu_read,
 };
 
 #define PATCH_FOPS(NAME)						\
@@ -985,6 +1078,7 @@ static struct file *ocxlflash_get_fd(void *ctx_cookie,
 	/* Patch the file ops that are not defined */
 	if (fops) {
 		PATCH_FOPS(poll);
+		PATCH_FOPS(read);
 	} else /* Use default ops */
 		fops = (struct file_operations *)&ocxl_afu_fops;
 
-- 
2.1.0

[PATCH v3 29/41] cxlflash: Support adapter context mmap and release

[Uma Krishnan]

The cxlflash userspace API requires that users be able to mmap and release
the adapter context. Support mapping by implementing the AFU mmap fop to
map the context MMIO space and install the corresponding page table entry
upon page fault. Similarly, implement the AFU release fop to terminate and
clean up the context when invoked.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 72 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 72 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index f531403..8a9f2f4 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -1029,10 +1029,80 @@ static ssize_t afu_read(struct file *file, char __user *buf, size_t count,
 	goto out;
 }
 
+/**
+ * afu_release() - release and free the context
+ * @inode:	File inode pointer.
+ * @file:	File associated with the context.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int afu_release(struct inode *inode, struct file *file)
+{
+	struct ocxlflash_context *ctx = file->private_data;
+	int i;
+
+	/* Unmap and free the interrupts associated with the context */
+	for (i = ctx->num_irqs; i >= 0; i--)
+		afu_unmap_irq(0, ctx, i, ctx);
+	free_afu_irqs(ctx);
+
+	return ocxlflash_release_context(ctx);
+}
+
+/**
+ * ocxlflash_mmap_fault() - mmap fault handler
+ * @vmf:	VM fault associated with current fault.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_mmap_fault(struct vm_fault *vmf)
+{
+	struct vm_area_struct *vma = vmf->vma;
+	struct ocxlflash_context *ctx = vma->vm_file->private_data;
+	u64 mmio_area, offset;
+
+	offset = vmf->pgoff << PAGE_SHIFT;
+	if (offset >= ctx->psn_size)
+		return VM_FAULT_SIGBUS;
+
+	mmio_area = ctx->psn_phys;
+	mmio_area += offset;
+
+	vm_insert_pfn(vma, vmf->address, mmio_area >> PAGE_SHIFT);
+	return VM_FAULT_NOPAGE;
+}
+
+static const struct vm_operations_struct ocxlflash_vmops = {
+	.fault = ocxlflash_mmap_fault,
+};
+
+/**
+ * afu_mmap() - map the fault handler operations
+ * @file:	File associated with the context.
+ * @vma:	VM area associated with mapping.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int afu_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	struct ocxlflash_context *ctx = file->private_data;
+
+	if ((vma_pages(vma) + vma->vm_pgoff) >
+	    (ctx->psn_size >> PAGE_SHIFT))
+		return -EINVAL;
+
+	vma->vm_flags |= VM_IO | VM_PFNMAP;
+	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+	vma->vm_ops = &ocxlflash_vmops;
+	return 0;
+}
+
 static const struct file_operations ocxl_afu_fops = {
 	.owner		= THIS_MODULE,
 	.poll		= afu_poll,
 	.read		= afu_read,
+	.release	= afu_release,
+	.mmap		= afu_mmap,
 };
 
 #define PATCH_FOPS(NAME)						\
@@ -1079,6 +1149,8 @@ static struct file *ocxlflash_get_fd(void *ctx_cookie,
 	if (fops) {
 		PATCH_FOPS(poll);
 		PATCH_FOPS(read);
+		PATCH_FOPS(release);
+		PATCH_FOPS(mmap);
 	} else /* Use default ops */
 		fops = (struct file_operations *)&ocxl_afu_fops;
 
-- 
2.1.0

[PATCH v3 29/41] cxlflash: Support adapter context mmap and release

[Uma Krishnan]

The cxlflash userspace API requires that users be able to mmap and release
the adapter context. Support mapping by implementing the AFU mmap fop to
map the context MMIO space and install the corresponding page table entry
upon page fault. Similarly, implement the AFU release fop to terminate and
clean up the context when invoked.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 72 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 72 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index f531403..8a9f2f4 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -1029,10 +1029,80 @@ static ssize_t afu_read(struct file *file, char __user *buf, size_t count,
 	goto out;
 }
 
+/**
+ * afu_release() - release and free the context
+ * @inode:	File inode pointer.
+ * @file:	File associated with the context.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int afu_release(struct inode *inode, struct file *file)
+{
+	struct ocxlflash_context *ctx = file->private_data;
+	int i;
+
+	/* Unmap and free the interrupts associated with the context */
+	for (i = ctx->num_irqs; i >= 0; i--)
+		afu_unmap_irq(0, ctx, i, ctx);
+	free_afu_irqs(ctx);
+
+	return ocxlflash_release_context(ctx);
+}
+
+/**
+ * ocxlflash_mmap_fault() - mmap fault handler
+ * @vmf:	VM fault associated with current fault.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_mmap_fault(struct vm_fault *vmf)
+{
+	struct vm_area_struct *vma = vmf->vma;
+	struct ocxlflash_context *ctx = vma->vm_file->private_data;
+	u64 mmio_area, offset;
+
+	offset = vmf->pgoff << PAGE_SHIFT;
+	if (offset >= ctx->psn_size)
+		return VM_FAULT_SIGBUS;
+
+	mmio_area = ctx->psn_phys;
+	mmio_area += offset;
+
+	vm_insert_pfn(vma, vmf->address, mmio_area >> PAGE_SHIFT);
+	return VM_FAULT_NOPAGE;
+}
+
+static const struct vm_operations_struct ocxlflash_vmops = {
+	.fault = ocxlflash_mmap_fault,
+};
+
+/**
+ * afu_mmap() - map the fault handler operations
+ * @file:	File associated with the context.
+ * @vma:	VM area associated with mapping.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int afu_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	struct ocxlflash_context *ctx = file->private_data;
+
+	if ((vma_pages(vma) + vma->vm_pgoff) >
+	    (ctx->psn_size >> PAGE_SHIFT))
+		return -EINVAL;
+
+	vma->vm_flags |= VM_IO | VM_PFNMAP;
+	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+	vma->vm_ops = &ocxlflash_vmops;
+	return 0;
+}
+
 static const struct file_operations ocxl_afu_fops = {
 	.owner		= THIS_MODULE,
 	.poll		= afu_poll,
 	.read		= afu_read,
+	.release	= afu_release,
+	.mmap		= afu_mmap,
 };
 
 #define PATCH_FOPS(NAME)						\
@@ -1079,6 +1149,8 @@ static struct file *ocxlflash_get_fd(void *ctx_cookie,
 	if (fops) {
 		PATCH_FOPS(poll);
 		PATCH_FOPS(read);
+		PATCH_FOPS(release);
+		PATCH_FOPS(mmap);
 	} else /* Use default ops */
 		fops = (struct file_operations *)&ocxl_afu_fops;
 
-- 
2.1.0

[PATCH v3 30/41] cxlflash: Support file descriptor mapping

[Uma Krishnan]

The cxlflash core fop API requires a way to invoke the fault and release
handlers of underlying transports using their native file-based APIs. This
provides the core with the ability to insert selectively itself into the
processing stream of these operations for cleanup. Implement these two
fops to map and release when requested.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 8a9f2f4..4bbc1d1 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -1267,6 +1267,30 @@ static int ocxlflash_start_work(void *ctx_cookie, u64 num_irqs)
 		afu_unmap_irq(0, ctx, i, ctx);
 	free_afu_irqs(ctx);
 	goto out;
+};
+
+/**
+ * ocxlflash_fd_mmap() - mmap handler for adapter file descriptor
+ * @file:	File installed with adapter file descriptor.
+ * @vma:	VM area associated with mapping.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_fd_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	return afu_mmap(file, vma);
+}
+
+/**
+ * ocxlflash_fd_release() - release the context associated with the file
+ * @inode:	File inode pointer.
+ * @file:	File associated with the adapter context.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_fd_release(struct inode *inode, struct file *file)
+{
+	return afu_release(inode, file);
 }
 
 /* Backend ops to ocxlflash services */
@@ -1292,4 +1316,6 @@ const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.get_fd			= ocxlflash_get_fd,
 	.fops_get_context	= ocxlflash_fops_get_context,
 	.start_work		= ocxlflash_start_work,
+	.fd_mmap		= ocxlflash_fd_mmap,
+	.fd_release		= ocxlflash_fd_release,
 };
-- 
2.1.0

[PATCH v3 30/41] cxlflash: Support file descriptor mapping

[Uma Krishnan]

The cxlflash core fop API requires a way to invoke the fault and release
handlers of underlying transports using their native file-based APIs. This
provides the core with the ability to insert selectively itself into the
processing stream of these operations for cleanup. Implement these two
fops to map and release when requested.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 8a9f2f4..4bbc1d1 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -1267,6 +1267,30 @@ static int ocxlflash_start_work(void *ctx_cookie, u64 num_irqs)
 		afu_unmap_irq(0, ctx, i, ctx);
 	free_afu_irqs(ctx);
 	goto out;
+};
+
+/**
+ * ocxlflash_fd_mmap() - mmap handler for adapter file descriptor
+ * @file:	File installed with adapter file descriptor.
+ * @vma:	VM area associated with mapping.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_fd_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	return afu_mmap(file, vma);
+}
+
+/**
+ * ocxlflash_fd_release() - release the context associated with the file
+ * @inode:	File inode pointer.
+ * @file:	File associated with the adapter context.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_fd_release(struct inode *inode, struct file *file)
+{
+	return afu_release(inode, file);
 }
 
 /* Backend ops to ocxlflash services */
@@ -1292,4 +1316,6 @@ const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.get_fd			= ocxlflash_get_fd,
 	.fops_get_context	= ocxlflash_fops_get_context,
 	.start_work		= ocxlflash_start_work,
+	.fd_mmap		= ocxlflash_fd_mmap,
+	.fd_release		= ocxlflash_fd_release,
 };
-- 
2.1.0

[PATCH v3 31/41] cxlflash: Introduce object handle fop

[Uma Krishnan]

OCXL requires that AFUs use an opaque object handle to represent
an AFU interrupt. The specification does not provide a common means
to communicate the object handle to the AFU - each AFU must define
this within the AFU specification. To support this model, the object
handle must be passed back to the core driver as it manages the AFU
specification (SISLite) for cxlflash. Note that for Power systems,
the object handle is the effective address of the trigger page.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/backend.h |  1 +
 drivers/scsi/cxlflash/cxl_hw.c  |  7 +++++++
 drivers/scsi/cxlflash/ocxl_hw.c | 18 ++++++++++++++++++
 3 files changed, 26 insertions(+)

diff --git a/drivers/scsi/cxlflash/backend.h b/drivers/scsi/cxlflash/backend.h
index f675bcb..bcd8a6c 100644
--- a/drivers/scsi/cxlflash/backend.h
+++ b/drivers/scsi/cxlflash/backend.h
@@ -23,6 +23,7 @@ struct cxlflash_backend_ops {
 	int (*map_afu_irq)(void *ctx_cookie, int num, irq_handler_t handler,
 			   void *cookie, char *name);
 	void (*unmap_afu_irq)(void *ctx_cookie, int num, void *cookie);
+	u64 (*get_irq_objhndl)(void *ctx_cookie, int irq);
 	int (*start_context)(void *ctx_cookie);
 	int (*stop_context)(void *ctx_cookie);
 	int (*afu_reset)(void *ctx_cookie);
diff --git a/drivers/scsi/cxlflash/cxl_hw.c b/drivers/scsi/cxlflash/cxl_hw.c
index a1d6d12..b42da88 100644
--- a/drivers/scsi/cxlflash/cxl_hw.c
+++ b/drivers/scsi/cxlflash/cxl_hw.c
@@ -49,6 +49,12 @@ static void cxlflash_unmap_afu_irq(void *ctx_cookie, int num, void *cookie)
 	cxl_unmap_afu_irq(ctx_cookie, num, cookie);
 }
 
+static u64 cxlflash_get_irq_objhndl(void *ctx_cookie, int irq)
+{
+	/* Dummy fop for cxl */
+	return 0;
+}
+
 static int cxlflash_start_context(void *ctx_cookie)
 {
 	return cxl_start_context(ctx_cookie, 0, NULL);
@@ -153,6 +159,7 @@ const struct cxlflash_backend_ops cxlflash_cxl_ops = {
 	.process_element	= cxlflash_process_element,
 	.map_afu_irq		= cxlflash_map_afu_irq,
 	.unmap_afu_irq		= cxlflash_unmap_afu_irq,
+	.get_irq_objhndl	= cxlflash_get_irq_objhndl,
 	.start_context		= cxlflash_start_context,
 	.stop_context		= cxlflash_stop_context,
 	.afu_reset		= cxlflash_afu_reset,
diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 4bbc1d1..f77f4d7 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -308,6 +308,23 @@ static void ocxlflash_unmap_afu_irq(void *ctx_cookie, int num, void *cookie)
 }
 
 /**
+ * ocxlflash_get_irq_objhndl() - get the object handle for an interrupt
+ * @ctx_cookie:	Context associated with the interrupt.
+ * @irq:	Interrupt number.
+ *
+ * Return: effective address of the mapped region
+ */
+static u64 ocxlflash_get_irq_objhndl(void *ctx_cookie, int irq)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+
+	if (irq < 0 || irq >= ctx->num_irqs)
+		return 0;
+
+	return (__force u64)ctx->irqs[irq].vtrig;
+}
+
+/**
  * start_context() - local routine to start a context
  * @ctx:	Adapter context to be started.
  *
@@ -1301,6 +1318,7 @@ const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.process_element	= ocxlflash_process_element,
 	.map_afu_irq		= ocxlflash_map_afu_irq,
 	.unmap_afu_irq		= ocxlflash_unmap_afu_irq,
+	.get_irq_objhndl	= ocxlflash_get_irq_objhndl,
 	.start_context		= ocxlflash_start_context,
 	.stop_context		= ocxlflash_stop_context,
 	.set_master		= ocxlflash_set_master,
-- 
2.1.0

[PATCH v3 31/41] cxlflash: Introduce object handle fop

[Uma Krishnan]

OCXL requires that AFUs use an opaque object handle to represent
an AFU interrupt. The specification does not provide a common means
to communicate the object handle to the AFU - each AFU must define
this within the AFU specification. To support this model, the object
handle must be passed back to the core driver as it manages the AFU
specification (SISLite) for cxlflash. Note that for Power systems,
the object handle is the effective address of the trigger page.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/backend.h |  1 +
 drivers/scsi/cxlflash/cxl_hw.c  |  7 +++++++
 drivers/scsi/cxlflash/ocxl_hw.c | 18 ++++++++++++++++++
 3 files changed, 26 insertions(+)

diff --git a/drivers/scsi/cxlflash/backend.h b/drivers/scsi/cxlflash/backend.h
index f675bcb..bcd8a6c 100644
--- a/drivers/scsi/cxlflash/backend.h
+++ b/drivers/scsi/cxlflash/backend.h
@@ -23,6 +23,7 @@ struct cxlflash_backend_ops {
 	int (*map_afu_irq)(void *ctx_cookie, int num, irq_handler_t handler,
 			   void *cookie, char *name);
 	void (*unmap_afu_irq)(void *ctx_cookie, int num, void *cookie);
+	u64 (*get_irq_objhndl)(void *ctx_cookie, int irq);
 	int (*start_context)(void *ctx_cookie);
 	int (*stop_context)(void *ctx_cookie);
 	int (*afu_reset)(void *ctx_cookie);
diff --git a/drivers/scsi/cxlflash/cxl_hw.c b/drivers/scsi/cxlflash/cxl_hw.c
index a1d6d12..b42da88 100644
--- a/drivers/scsi/cxlflash/cxl_hw.c
+++ b/drivers/scsi/cxlflash/cxl_hw.c
@@ -49,6 +49,12 @@ static void cxlflash_unmap_afu_irq(void *ctx_cookie, int num, void *cookie)
 	cxl_unmap_afu_irq(ctx_cookie, num, cookie);
 }
 
+static u64 cxlflash_get_irq_objhndl(void *ctx_cookie, int irq)
+{
+	/* Dummy fop for cxl */
+	return 0;
+}
+
 static int cxlflash_start_context(void *ctx_cookie)
 {
 	return cxl_start_context(ctx_cookie, 0, NULL);
@@ -153,6 +159,7 @@ const struct cxlflash_backend_ops cxlflash_cxl_ops = {
 	.process_element	= cxlflash_process_element,
 	.map_afu_irq		= cxlflash_map_afu_irq,
 	.unmap_afu_irq		= cxlflash_unmap_afu_irq,
+	.get_irq_objhndl	= cxlflash_get_irq_objhndl,
 	.start_context		= cxlflash_start_context,
 	.stop_context		= cxlflash_stop_context,
 	.afu_reset		= cxlflash_afu_reset,
diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 4bbc1d1..f77f4d7 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -308,6 +308,23 @@ static void ocxlflash_unmap_afu_irq(void *ctx_cookie, int num, void *cookie)
 }
 
 /**
+ * ocxlflash_get_irq_objhndl() - get the object handle for an interrupt
+ * @ctx_cookie:	Context associated with the interrupt.
+ * @irq:	Interrupt number.
+ *
+ * Return: effective address of the mapped region
+ */
+static u64 ocxlflash_get_irq_objhndl(void *ctx_cookie, int irq)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+
+	if (irq < 0 || irq >= ctx->num_irqs)
+		return 0;
+
+	return (__force u64)ctx->irqs[irq].vtrig;
+}
+
+/**
  * start_context() - local routine to start a context
  * @ctx:	Adapter context to be started.
  *
@@ -1301,6 +1318,7 @@ const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.process_element	= ocxlflash_process_element,
 	.map_afu_irq		= ocxlflash_map_afu_irq,
 	.unmap_afu_irq		= ocxlflash_unmap_afu_irq,
+	.get_irq_objhndl	= ocxlflash_get_irq_objhndl,
 	.start_context		= ocxlflash_start_context,
 	.stop_context		= ocxlflash_stop_context,
 	.set_master		= ocxlflash_set_master,
-- 
2.1.0

[PATCH v3 32/41] cxlflash: Setup LISNs for user contexts

[Uma Krishnan]

The SISLite specification has been updated for OCXL to support
communicating data to generate AFU interrupts to the AFU. This includes
a new capability bit that is advertised for OCXL AFUs and new registers
to hold the object handle and translation PASID of each interrupt. For
Power, the object handle is the mapped trigger page. Note that because
these mappings are kernel only, the PASID of a kernel context must be
used to satisfy the translation.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/common.h    |  5 +++++
 drivers/scsi/cxlflash/sislite.h   |  5 +++++
 drivers/scsi/cxlflash/superpipe.c | 14 ++++++++++++++
 3 files changed, 24 insertions(+)

diff --git a/drivers/scsi/cxlflash/common.h b/drivers/scsi/cxlflash/common.h
index d7fccea..b69fd32 100644
--- a/drivers/scsi/cxlflash/common.h
+++ b/drivers/scsi/cxlflash/common.h
@@ -273,6 +273,11 @@ static inline bool afu_has_cap(struct afu *afu, u64 cap)
 	return afu_cap & cap;
 }
 
+static inline bool afu_is_ocxl_lisn(struct afu *afu)
+{
+	return afu_has_cap(afu, SISL_INTVER_CAP_OCXL_LISN);
+}
+
 static inline bool afu_is_afu_debug(struct afu *afu)
 {
 	return afu_has_cap(afu, SISL_INTVER_CAP_AFU_DEBUG);
diff --git a/drivers/scsi/cxlflash/sislite.h b/drivers/scsi/cxlflash/sislite.h
index d8940f1..c08b9d3 100644
--- a/drivers/scsi/cxlflash/sislite.h
+++ b/drivers/scsi/cxlflash/sislite.h
@@ -310,6 +310,10 @@ struct sisl_ctrl_map {
 #define SISL_CTX_CAP_WRITE_CMD         0x0000000000000002ULL /* afu_rc 0x21 */
 #define SISL_CTX_CAP_READ_CMD          0x0000000000000001ULL /* afu_rc 0x21 */
 	__be64 mbox_r;
+	__be64 lisn_pasid[2];
+	/* pasid _a arg must be ULL */
+#define SISL_LISN_PASID(_a, _b)	(((_a) << 32) | (_b))
+	__be64 lisn_ea[3];
 };
 
 /* single copy global regs */
@@ -416,6 +420,7 @@ struct sisl_global_regs {
 #define SISL_INTVER_CAP_RESERVED_CMD_MODE_B	0x100000000000ULL
 #define SISL_INTVER_CAP_LUN_PROVISION		0x080000000000ULL
 #define SISL_INTVER_CAP_AFU_DEBUG		0x040000000000ULL
+#define SISL_INTVER_CAP_OCXL_LISN		0x020000000000ULL
 };
 
 #define CXLFLASH_NUM_FC_PORTS_PER_BANK	2	/* fixed # of ports per bank */
diff --git a/drivers/scsi/cxlflash/superpipe.c b/drivers/scsi/cxlflash/superpipe.c
index 2fe79df..04a3bf9 100644
--- a/drivers/scsi/cxlflash/superpipe.c
+++ b/drivers/scsi/cxlflash/superpipe.c
@@ -269,6 +269,7 @@ static int afu_attach(struct cxlflash_cfg *cfg, struct ctx_info *ctxi)
 	int rc = 0;
 	struct hwq *hwq = get_hwq(afu, PRIMARY_HWQ);
 	u64 val;
+	int i;
 
 	/* Unlock cap and restrict user to read/write cmds in translated mode */
 	readq_be(&ctrl_map->mbox_r);
@@ -282,6 +283,19 @@ static int afu_attach(struct cxlflash_cfg *cfg, struct ctx_info *ctxi)
 		goto out;
 	}
 
+	if (afu_is_ocxl_lisn(afu)) {
+		/* Set up the LISN effective address for each interrupt */
+		for (i = 0; i < ctxi->irqs; i++) {
+			val = cfg->ops->get_irq_objhndl(ctxi->ctx, i);
+			writeq_be(val, &ctrl_map->lisn_ea[i]);
+		}
+
+		/* Use primary HWQ PASID as identifier for all interrupts */
+		val = hwq->ctx_hndl;
+		writeq_be(SISL_LISN_PASID(val, val), &ctrl_map->lisn_pasid[0]);
+		writeq_be(SISL_LISN_PASID(0UL, val), &ctrl_map->lisn_pasid[1]);
+	}
+
 	/* Set up MMIO registers pointing to the RHT */
 	writeq_be((u64)ctxi->rht_start, &ctrl_map->rht_start);
 	val = SISL_RHT_CNT_ID((u64)MAX_RHT_PER_CONTEXT, (u64)(hwq->ctx_hndl));
-- 
2.1.0

[PATCH v3 32/41] cxlflash: Setup LISNs for user contexts

[Uma Krishnan]

The SISLite specification has been updated for OCXL to support
communicating data to generate AFU interrupts to the AFU. This includes
a new capability bit that is advertised for OCXL AFUs and new registers
to hold the object handle and translation PASID of each interrupt. For
Power, the object handle is the mapped trigger page. Note that because
these mappings are kernel only, the PASID of a kernel context must be
used to satisfy the translation.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/common.h    |  5 +++++
 drivers/scsi/cxlflash/sislite.h   |  5 +++++
 drivers/scsi/cxlflash/superpipe.c | 14 ++++++++++++++
 3 files changed, 24 insertions(+)

diff --git a/drivers/scsi/cxlflash/common.h b/drivers/scsi/cxlflash/common.h
index d7fccea..b69fd32 100644
--- a/drivers/scsi/cxlflash/common.h
+++ b/drivers/scsi/cxlflash/common.h
@@ -273,6 +273,11 @@ static inline bool afu_has_cap(struct afu *afu, u64 cap)
 	return afu_cap & cap;
 }
 
+static inline bool afu_is_ocxl_lisn(struct afu *afu)
+{
+	return afu_has_cap(afu, SISL_INTVER_CAP_OCXL_LISN);
+}
+
 static inline bool afu_is_afu_debug(struct afu *afu)
 {
 	return afu_has_cap(afu, SISL_INTVER_CAP_AFU_DEBUG);
diff --git a/drivers/scsi/cxlflash/sislite.h b/drivers/scsi/cxlflash/sislite.h
index d8940f1..c08b9d3 100644
--- a/drivers/scsi/cxlflash/sislite.h
+++ b/drivers/scsi/cxlflash/sislite.h
@@ -310,6 +310,10 @@ struct sisl_ctrl_map {
 #define SISL_CTX_CAP_WRITE_CMD         0x0000000000000002ULL /* afu_rc 0x21 */
 #define SISL_CTX_CAP_READ_CMD          0x0000000000000001ULL /* afu_rc 0x21 */
 	__be64 mbox_r;
+	__be64 lisn_pasid[2];
+	/* pasid _a arg must be ULL */
+#define SISL_LISN_PASID(_a, _b)	(((_a) << 32) | (_b))
+	__be64 lisn_ea[3];
 };
 
 /* single copy global regs */
@@ -416,6 +420,7 @@ struct sisl_global_regs {
 #define SISL_INTVER_CAP_RESERVED_CMD_MODE_B	0x100000000000ULL
 #define SISL_INTVER_CAP_LUN_PROVISION		0x080000000000ULL
 #define SISL_INTVER_CAP_AFU_DEBUG		0x040000000000ULL
+#define SISL_INTVER_CAP_OCXL_LISN		0x020000000000ULL
 };
 
 #define CXLFLASH_NUM_FC_PORTS_PER_BANK	2	/* fixed # of ports per bank */
diff --git a/drivers/scsi/cxlflash/superpipe.c b/drivers/scsi/cxlflash/superpipe.c
index 2fe79df..04a3bf9 100644
--- a/drivers/scsi/cxlflash/superpipe.c
+++ b/drivers/scsi/cxlflash/superpipe.c
@@ -269,6 +269,7 @@ static int afu_attach(struct cxlflash_cfg *cfg, struct ctx_info *ctxi)
 	int rc = 0;
 	struct hwq *hwq = get_hwq(afu, PRIMARY_HWQ);
 	u64 val;
+	int i;
 
 	/* Unlock cap and restrict user to read/write cmds in translated mode */
 	readq_be(&ctrl_map->mbox_r);
@@ -282,6 +283,19 @@ static int afu_attach(struct cxlflash_cfg *cfg, struct ctx_info *ctxi)
 		goto out;
 	}
 
+	if (afu_is_ocxl_lisn(afu)) {
+		/* Set up the LISN effective address for each interrupt */
+		for (i = 0; i < ctxi->irqs; i++) {
+			val = cfg->ops->get_irq_objhndl(ctxi->ctx, i);
+			writeq_be(val, &ctrl_map->lisn_ea[i]);
+		}
+
+		/* Use primary HWQ PASID as identifier for all interrupts */
+		val = hwq->ctx_hndl;
+		writeq_be(SISL_LISN_PASID(val, val), &ctrl_map->lisn_pasid[0]);
+		writeq_be(SISL_LISN_PASID(0UL, val), &ctrl_map->lisn_pasid[1]);
+	}
+
 	/* Set up MMIO registers pointing to the RHT */
 	writeq_be((u64)ctxi->rht_start, &ctrl_map->rht_start);
 	val = SISL_RHT_CNT_ID((u64)MAX_RHT_PER_CONTEXT, (u64)(hwq->ctx_hndl));
-- 
2.1.0

[PATCH v3 33/41] cxlflash: Setup LISNs for master contexts

[Uma Krishnan]

Similar to user contexts, master contexts also require that the per-context
LISN registers be programmed for certain AFUs. The mapped trigger page is
obtained from underlying transport and registered with AFU for each master
context.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/main.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c
index 5d754d1..8c55fcd 100644
--- a/drivers/scsi/cxlflash/main.c
+++ b/drivers/scsi/cxlflash/main.c
@@ -1756,6 +1756,8 @@ static int init_global(struct cxlflash_cfg *cfg)
 	u64 wwpn[MAX_FC_PORTS];	/* wwpn of AFU ports */
 	int i = 0, num_ports = 0;
 	int rc = 0;
+	int j;
+	void *ctx;
 	u64 reg;
 
 	rc = read_vpd(cfg, &wwpn[0]);
@@ -1816,6 +1818,25 @@ static int init_global(struct cxlflash_cfg *cfg)
 		msleep(100);
 	}
 
+	if (afu_is_ocxl_lisn(afu)) {
+		/* Set up the LISN effective address for each master */
+		for (i = 0; i < afu->num_hwqs; i++) {
+			hwq = get_hwq(afu, i);
+			ctx = hwq->ctx_cookie;
+
+			for (j = 0; j < hwq->num_irqs; j++) {
+				reg = cfg->ops->get_irq_objhndl(ctx, j);
+				writeq_be(reg, &hwq->ctrl_map->lisn_ea[j]);
+			}
+
+			reg = hwq->ctx_hndl;
+			writeq_be(SISL_LISN_PASID(reg, reg),
+				  &hwq->ctrl_map->lisn_pasid[0]);
+			writeq_be(SISL_LISN_PASID(0UL, reg),
+				  &hwq->ctrl_map->lisn_pasid[1]);
+		}
+	}
+
 	/* Set up master's own CTX_CAP to allow real mode, host translation */
 	/* tables, afu cmds and read/write GSCSI cmds. */
 	/* First, unlock ctx_cap write by reading mbox */
-- 
2.1.0

[PATCH v3 33/41] cxlflash: Setup LISNs for master contexts

[Uma Krishnan]

Similar to user contexts, master contexts also require that the per-context
LISN registers be programmed for certain AFUs. The mapped trigger page is
obtained from underlying transport and registered with AFU for each master
context.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/main.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c
index 5d754d1..8c55fcd 100644
--- a/drivers/scsi/cxlflash/main.c
+++ b/drivers/scsi/cxlflash/main.c
@@ -1756,6 +1756,8 @@ static int init_global(struct cxlflash_cfg *cfg)
 	u64 wwpn[MAX_FC_PORTS];	/* wwpn of AFU ports */
 	int i = 0, num_ports = 0;
 	int rc = 0;
+	int j;
+	void *ctx;
 	u64 reg;
 
 	rc = read_vpd(cfg, &wwpn[0]);
@@ -1816,6 +1818,25 @@ static int init_global(struct cxlflash_cfg *cfg)
 		msleep(100);
 	}
 
+	if (afu_is_ocxl_lisn(afu)) {
+		/* Set up the LISN effective address for each master */
+		for (i = 0; i < afu->num_hwqs; i++) {
+			hwq = get_hwq(afu, i);
+			ctx = hwq->ctx_cookie;
+
+			for (j = 0; j < hwq->num_irqs; j++) {
+				reg = cfg->ops->get_irq_objhndl(ctx, j);
+				writeq_be(reg, &hwq->ctrl_map->lisn_ea[j]);
+			}
+
+			reg = hwq->ctx_hndl;
+			writeq_be(SISL_LISN_PASID(reg, reg),
+				  &hwq->ctrl_map->lisn_pasid[0]);
+			writeq_be(SISL_LISN_PASID(0UL, reg),
+				  &hwq->ctrl_map->lisn_pasid[1]);
+		}
+	}
+
 	/* Set up master's own CTX_CAP to allow real mode, host translation */
 	/* tables, afu cmds and read/write GSCSI cmds. */
 	/* First, unlock ctx_cap write by reading mbox */
-- 
2.1.0

[PATCH v3 34/41] cxlflash: Update synchronous interrupt status bits

[Uma Krishnan]

The SISLite specification has been updated to define new synchronous
interrupt status bits. These bits are set by the AFU when a given PASID or
EA is bad and a synchronous interrupt is triggered.

The SISLite header file is updated to support these new bits. Note that
there are also some formatting updates to some of the existing bits to
allow all of the definitions to line up uniformly.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/sislite.h | 35 +++++++++++++++++++++--------------
 1 file changed, 21 insertions(+), 14 deletions(-)

diff --git a/drivers/scsi/cxlflash/sislite.h b/drivers/scsi/cxlflash/sislite.h
index c08b9d3..874abce 100644
--- a/drivers/scsi/cxlflash/sislite.h
+++ b/drivers/scsi/cxlflash/sislite.h
@@ -258,23 +258,30 @@ struct sisl_host_map {
 				 * exit since there is no way to tell which
 				 * command caused the error.
 				 */
-#define SISL_ISTATUS_PERM_ERR_CMDROOM    0x0010ULL	/* b59, user error */
-#define SISL_ISTATUS_PERM_ERR_RCB_READ   0x0008ULL	/* b60, user error */
-#define SISL_ISTATUS_PERM_ERR_SA_WRITE   0x0004ULL	/* b61, user error */
-#define SISL_ISTATUS_PERM_ERR_RRQ_WRITE  0x0002ULL	/* b62, user error */
+#define SISL_ISTATUS_PERM_ERR_LISN_3_EA		0x0400ULL /* b53, user error */
+#define SISL_ISTATUS_PERM_ERR_LISN_2_EA		0x0200ULL /* b54, user error */
+#define SISL_ISTATUS_PERM_ERR_LISN_1_EA		0x0100ULL /* b55, user error */
+#define SISL_ISTATUS_PERM_ERR_LISN_3_PASID	0x0080ULL /* b56, user error */
+#define SISL_ISTATUS_PERM_ERR_LISN_2_PASID	0x0040ULL /* b57, user error */
+#define SISL_ISTATUS_PERM_ERR_LISN_1_PASID	0x0020ULL /* b58, user error */
+#define SISL_ISTATUS_PERM_ERR_CMDROOM		0x0010ULL /* b59, user error */
+#define SISL_ISTATUS_PERM_ERR_RCB_READ		0x0008ULL /* b60, user error */
+#define SISL_ISTATUS_PERM_ERR_SA_WRITE		0x0004ULL /* b61, user error */
+#define SISL_ISTATUS_PERM_ERR_RRQ_WRITE		0x0002ULL /* b62, user error */
 	/* Page in wait accessing RCB/IOASA/RRQ is reported in b63.
 	 * Same error in data/LXT/RHT access is reported via IOASA.
 	 */
-#define SISL_ISTATUS_TEMP_ERR_PAGEIN     0x0001ULL	/* b63, can be generated
-							 * only when AFU auto
-							 * retry is disabled.
-							 * If user can determine
-							 * the command that
-							 * caused the error, it
-							 * can be retried.
-							 */
-#define SISL_ISTATUS_UNMASK  (0x001FULL)	/* 1 means unmasked */
-#define SISL_ISTATUS_MASK    ~(SISL_ISTATUS_UNMASK)	/* 1 means masked */
+#define SISL_ISTATUS_TEMP_ERR_PAGEIN		0x0001ULL /* b63, can only be
+							   * generated when AFU
+							   * auto retry is
+							   * disabled. If user
+							   * can determine the
+							   * command that caused
+							   * the error, it can
+							   * be retried.
+							   */
+#define SISL_ISTATUS_UNMASK	(0x07FFULL)		/* 1 means unmasked */
+#define SISL_ISTATUS_MASK	~(SISL_ISTATUS_UNMASK)	/* 1 means masked */
 
 	__be64 intr_clear;
 	__be64 intr_mask;
-- 
2.1.0

[PATCH v3 34/41] cxlflash: Update synchronous interrupt status bits

[Uma Krishnan]

The SISLite specification has been updated to define new synchronous
interrupt status bits. These bits are set by the AFU when a given PASID or
EA is bad and a synchronous interrupt is triggered.

The SISLite header file is updated to support these new bits. Note that
there are also some formatting updates to some of the existing bits to
allow all of the definitions to line up uniformly.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/sislite.h | 35 +++++++++++++++++++++--------------
 1 file changed, 21 insertions(+), 14 deletions(-)

diff --git a/drivers/scsi/cxlflash/sislite.h b/drivers/scsi/cxlflash/sislite.h
index c08b9d3..874abce 100644
--- a/drivers/scsi/cxlflash/sislite.h
+++ b/drivers/scsi/cxlflash/sislite.h
@@ -258,23 +258,30 @@ struct sisl_host_map {
 				 * exit since there is no way to tell which
 				 * command caused the error.
 				 */
-#define SISL_ISTATUS_PERM_ERR_CMDROOM    0x0010ULL	/* b59, user error */
-#define SISL_ISTATUS_PERM_ERR_RCB_READ   0x0008ULL	/* b60, user error */
-#define SISL_ISTATUS_PERM_ERR_SA_WRITE   0x0004ULL	/* b61, user error */
-#define SISL_ISTATUS_PERM_ERR_RRQ_WRITE  0x0002ULL	/* b62, user error */
+#define SISL_ISTATUS_PERM_ERR_LISN_3_EA		0x0400ULL /* b53, user error */
+#define SISL_ISTATUS_PERM_ERR_LISN_2_EA		0x0200ULL /* b54, user error */
+#define SISL_ISTATUS_PERM_ERR_LISN_1_EA		0x0100ULL /* b55, user error */
+#define SISL_ISTATUS_PERM_ERR_LISN_3_PASID	0x0080ULL /* b56, user error */
+#define SISL_ISTATUS_PERM_ERR_LISN_2_PASID	0x0040ULL /* b57, user error */
+#define SISL_ISTATUS_PERM_ERR_LISN_1_PASID	0x0020ULL /* b58, user error */
+#define SISL_ISTATUS_PERM_ERR_CMDROOM		0x0010ULL /* b59, user error */
+#define SISL_ISTATUS_PERM_ERR_RCB_READ		0x0008ULL /* b60, user error */
+#define SISL_ISTATUS_PERM_ERR_SA_WRITE		0x0004ULL /* b61, user error */
+#define SISL_ISTATUS_PERM_ERR_RRQ_WRITE		0x0002ULL /* b62, user error */
 	/* Page in wait accessing RCB/IOASA/RRQ is reported in b63.
 	 * Same error in data/LXT/RHT access is reported via IOASA.
 	 */
-#define SISL_ISTATUS_TEMP_ERR_PAGEIN     0x0001ULL	/* b63, can be generated
-							 * only when AFU auto
-							 * retry is disabled.
-							 * If user can determine
-							 * the command that
-							 * caused the error, it
-							 * can be retried.
-							 */
-#define SISL_ISTATUS_UNMASK  (0x001FULL)	/* 1 means unmasked */
-#define SISL_ISTATUS_MASK    ~(SISL_ISTATUS_UNMASK)	/* 1 means masked */
+#define SISL_ISTATUS_TEMP_ERR_PAGEIN		0x0001ULL /* b63, can only be
+							   * generated when AFU
+							   * auto retry is
+							   * disabled. If user
+							   * can determine the
+							   * command that caused
+							   * the error, it can
+							   * be retried.
+							   */
+#define SISL_ISTATUS_UNMASK	(0x07FFULL)		/* 1 means unmasked */
+#define SISL_ISTATUS_MASK	~(SISL_ISTATUS_UNMASK)	/* 1 means masked */
 
 	__be64 intr_clear;
 	__be64 intr_mask;
-- 
2.1.0

[PATCH v3 35/41] cxlflash: Introduce OCXL context state machine

[Uma Krishnan]

In order to protect the OCXL hardware contexts from getting clobbered,
a simple state machine is added to indicate when a context is in open,
close or start state. The expected states are validated throughout the
code to prevent illegal operations on a context. A mutex is added to
protect writes to the context state field.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 59 ++++++++++++++++++++++++++++++++++++++---
 drivers/scsi/cxlflash/ocxl_hw.h |  8 ++++++
 2 files changed, 64 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index f77f4d7..89d3d89 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -163,6 +163,16 @@ static struct file *ocxlflash_getfile(struct device *dev, const char *name,
 static void __iomem *ocxlflash_psa_map(void *ctx_cookie)
 {
 	struct ocxlflash_context *ctx = ctx_cookie;
+	struct device *dev = ctx->hw_afu->dev;
+
+	mutex_lock(&ctx->state_mutex);
+	if (ctx->state != STARTED) {
+		dev_err(dev, "%s: Context not started, state=%d\n", __func__,
+			ctx->state);
+		mutex_unlock(&ctx->state_mutex);
+		return NULL;
+	}
+	mutex_unlock(&ctx->state_mutex);
 
 	return ioremap(ctx->psn_phys, ctx->psn_size);
 }
@@ -343,6 +353,14 @@ static int start_context(struct ocxlflash_context *ctx)
 	int rc = 0;
 	u32 pid;
 
+	mutex_lock(&ctx->state_mutex);
+	if (ctx->state != OPENED) {
+		dev_err(dev, "%s: Context state invalid, state=%d\n",
+			__func__, ctx->state);
+		rc = -EINVAL;
+		goto out;
+	}
+
 	if (master) {
 		ctx->psn_size = acfg->global_mmio_size;
 		ctx->psn_phys = afu->gmmio_phys;
@@ -366,7 +384,10 @@ static int start_context(struct ocxlflash_context *ctx)
 			__func__, rc);
 		goto out;
 	}
+
+	ctx->state = STARTED;
 out:
+	mutex_unlock(&ctx->state_mutex);
 	return rc;
 }
 
@@ -396,7 +417,15 @@ static int ocxlflash_stop_context(void *ctx_cookie)
 	struct ocxl_afu_config *acfg = &afu->acfg;
 	struct pci_dev *pdev = afu->pdev;
 	struct device *dev = afu->dev;
-	int rc;
+	enum ocxlflash_ctx_state state;
+	int rc = 0;
+
+	mutex_lock(&ctx->state_mutex);
+	state = ctx->state;
+	ctx->state = CLOSED;
+	mutex_unlock(&ctx->state_mutex);
+	if (state != STARTED)
+		goto out;
 
 	rc = ocxl_config_terminate_pasid(pdev, acfg->dvsec_afu_control_pos,
 					 ctx->pe);
@@ -474,7 +503,9 @@ static void *ocxlflash_dev_context_init(struct pci_dev *pdev, void *afu_cookie)
 
 	spin_lock_init(&ctx->slock);
 	init_waitqueue_head(&ctx->wq);
+	mutex_init(&ctx->state_mutex);
 
+	ctx->state = OPENED;
 	ctx->pe = rc;
 	ctx->master = false;
 	ctx->mapping = NULL;
@@ -499,11 +530,23 @@ static void *ocxlflash_dev_context_init(struct pci_dev *pdev, void *afu_cookie)
 static int ocxlflash_release_context(void *ctx_cookie)
 {
 	struct ocxlflash_context *ctx = ctx_cookie;
+	struct device *dev;
 	int rc = 0;
 
 	if (!ctx)
 		goto out;
 
+	dev = ctx->hw_afu->dev;
+	mutex_lock(&ctx->state_mutex);
+	if (ctx->state >= STARTED) {
+		dev_err(dev, "%s: Context in use, state=%d\n", __func__,
+			ctx->state);
+		mutex_unlock(&ctx->state_mutex);
+		rc = -EBUSY;
+		goto out;
+	}
+	mutex_unlock(&ctx->state_mutex);
+
 	idr_remove(&ctx->hw_afu->idr, ctx->pe);
 	ocxlflash_release_mapping(ctx);
 	kfree(ctx);
@@ -947,7 +990,7 @@ static unsigned int afu_poll(struct file *file, struct poll_table_struct *poll)
 	spin_lock_irqsave(&ctx->slock, lock_flags);
 	if (ctx_event_pending(ctx))
 		mask |= POLLIN | POLLRDNORM;
-	else
+	else if (ctx->state == CLOSED)
 		mask |= POLLERR;
 	spin_unlock_irqrestore(&ctx->slock, lock_flags);
 
@@ -990,7 +1033,7 @@ static ssize_t afu_read(struct file *file, char __user *buf, size_t count,
 	for (;;) {
 		prepare_to_wait(&ctx->wq, &event_wait, TASK_INTERRUPTIBLE);
 
-		if (ctx_event_pending(ctx))
+		if (ctx_event_pending(ctx) || (ctx->state == CLOSED))
 			break;
 
 		if (file->f_flags & O_NONBLOCK) {
@@ -1076,12 +1119,22 @@ static int ocxlflash_mmap_fault(struct vm_fault *vmf)
 {
 	struct vm_area_struct *vma = vmf->vma;
 	struct ocxlflash_context *ctx = vma->vm_file->private_data;
+	struct device *dev = ctx->hw_afu->dev;
 	u64 mmio_area, offset;
 
 	offset = vmf->pgoff << PAGE_SHIFT;
 	if (offset >= ctx->psn_size)
 		return VM_FAULT_SIGBUS;
 
+	mutex_lock(&ctx->state_mutex);
+	if (ctx->state != STARTED) {
+		dev_err(dev, "%s: Context not started, state=%d\n",
+			__func__, ctx->state);
+		mutex_unlock(&ctx->state_mutex);
+		return VM_FAULT_SIGBUS;
+	}
+	mutex_unlock(&ctx->state_mutex);
+
 	mmio_area = ctx->psn_phys;
 	mmio_area += offset;
 
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index acd2801..1829e55 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -46,6 +46,12 @@ struct ocxl_hw_afu {
 	bool is_present;		/* Function has AFUs defined */
 };
 
+enum ocxlflash_ctx_state {
+	CLOSED,
+	OPENED,
+	STARTED
+};
+
 struct ocxlflash_context {
 	struct ocxl_hw_afu *hw_afu;	/* HW AFU back pointer */
 	struct address_space *mapping;	/* Mapping for pseudo filesystem */
@@ -57,6 +63,8 @@ struct ocxlflash_context {
 
 	spinlock_t slock;		/* Protects irq/fault/event updates */
 	wait_queue_head_t wq;		/* Wait queue for poll and interrupts */
+	struct mutex state_mutex;	/* Mutex to update context state */
+	enum ocxlflash_ctx_state state;	/* Context state */
 
 	struct ocxlflash_irqs *irqs;	/* Pointer to array of structures */
 	int num_irqs;			/* Number of interrupts */
-- 
2.1.0

[PATCH v3 35/41] cxlflash: Introduce OCXL context state machine

[Uma Krishnan]

In order to protect the OCXL hardware contexts from getting clobbered,
a simple state machine is added to indicate when a context is in open,
close or start state. The expected states are validated throughout the
code to prevent illegal operations on a context. A mutex is added to
protect writes to the context state field.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 59 ++++++++++++++++++++++++++++++++++++++---
 drivers/scsi/cxlflash/ocxl_hw.h |  8 ++++++
 2 files changed, 64 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index f77f4d7..89d3d89 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -163,6 +163,16 @@ static struct file *ocxlflash_getfile(struct device *dev, const char *name,
 static void __iomem *ocxlflash_psa_map(void *ctx_cookie)
 {
 	struct ocxlflash_context *ctx = ctx_cookie;
+	struct device *dev = ctx->hw_afu->dev;
+
+	mutex_lock(&ctx->state_mutex);
+	if (ctx->state != STARTED) {
+		dev_err(dev, "%s: Context not started, state=%d\n", __func__,
+			ctx->state);
+		mutex_unlock(&ctx->state_mutex);
+		return NULL;
+	}
+	mutex_unlock(&ctx->state_mutex);
 
 	return ioremap(ctx->psn_phys, ctx->psn_size);
 }
@@ -343,6 +353,14 @@ static int start_context(struct ocxlflash_context *ctx)
 	int rc = 0;
 	u32 pid;
 
+	mutex_lock(&ctx->state_mutex);
+	if (ctx->state != OPENED) {
+		dev_err(dev, "%s: Context state invalid, state=%d\n",
+			__func__, ctx->state);
+		rc = -EINVAL;
+		goto out;
+	}
+
 	if (master) {
 		ctx->psn_size = acfg->global_mmio_size;
 		ctx->psn_phys = afu->gmmio_phys;
@@ -366,7 +384,10 @@ static int start_context(struct ocxlflash_context *ctx)
 			__func__, rc);
 		goto out;
 	}
+
+	ctx->state = STARTED;
 out:
+	mutex_unlock(&ctx->state_mutex);
 	return rc;
 }
 
@@ -396,7 +417,15 @@ static int ocxlflash_stop_context(void *ctx_cookie)
 	struct ocxl_afu_config *acfg = &afu->acfg;
 	struct pci_dev *pdev = afu->pdev;
 	struct device *dev = afu->dev;
-	int rc;
+	enum ocxlflash_ctx_state state;
+	int rc = 0;
+
+	mutex_lock(&ctx->state_mutex);
+	state = ctx->state;
+	ctx->state = CLOSED;
+	mutex_unlock(&ctx->state_mutex);
+	if (state != STARTED)
+		goto out;
 
 	rc = ocxl_config_terminate_pasid(pdev, acfg->dvsec_afu_control_pos,
 					 ctx->pe);
@@ -474,7 +503,9 @@ static void *ocxlflash_dev_context_init(struct pci_dev *pdev, void *afu_cookie)
 
 	spin_lock_init(&ctx->slock);
 	init_waitqueue_head(&ctx->wq);
+	mutex_init(&ctx->state_mutex);
 
+	ctx->state = OPENED;
 	ctx->pe = rc;
 	ctx->master = false;
 	ctx->mapping = NULL;
@@ -499,11 +530,23 @@ static void *ocxlflash_dev_context_init(struct pci_dev *pdev, void *afu_cookie)
 static int ocxlflash_release_context(void *ctx_cookie)
 {
 	struct ocxlflash_context *ctx = ctx_cookie;
+	struct device *dev;
 	int rc = 0;
 
 	if (!ctx)
 		goto out;
 
+	dev = ctx->hw_afu->dev;
+	mutex_lock(&ctx->state_mutex);
+	if (ctx->state >= STARTED) {
+		dev_err(dev, "%s: Context in use, state=%d\n", __func__,
+			ctx->state);
+		mutex_unlock(&ctx->state_mutex);
+		rc = -EBUSY;
+		goto out;
+	}
+	mutex_unlock(&ctx->state_mutex);
+
 	idr_remove(&ctx->hw_afu->idr, ctx->pe);
 	ocxlflash_release_mapping(ctx);
 	kfree(ctx);
@@ -947,7 +990,7 @@ static unsigned int afu_poll(struct file *file, struct poll_table_struct *poll)
 	spin_lock_irqsave(&ctx->slock, lock_flags);
 	if (ctx_event_pending(ctx))
 		mask |= POLLIN | POLLRDNORM;
-	else
+	else if (ctx->state == CLOSED)
 		mask |= POLLERR;
 	spin_unlock_irqrestore(&ctx->slock, lock_flags);
 
@@ -990,7 +1033,7 @@ static ssize_t afu_read(struct file *file, char __user *buf, size_t count,
 	for (;;) {
 		prepare_to_wait(&ctx->wq, &event_wait, TASK_INTERRUPTIBLE);
 
-		if (ctx_event_pending(ctx))
+		if (ctx_event_pending(ctx) || (ctx->state == CLOSED))
 			break;
 
 		if (file->f_flags & O_NONBLOCK) {
@@ -1076,12 +1119,22 @@ static int ocxlflash_mmap_fault(struct vm_fault *vmf)
 {
 	struct vm_area_struct *vma = vmf->vma;
 	struct ocxlflash_context *ctx = vma->vm_file->private_data;
+	struct device *dev = ctx->hw_afu->dev;
 	u64 mmio_area, offset;
 
 	offset = vmf->pgoff << PAGE_SHIFT;
 	if (offset >= ctx->psn_size)
 		return VM_FAULT_SIGBUS;
 
+	mutex_lock(&ctx->state_mutex);
+	if (ctx->state != STARTED) {
+		dev_err(dev, "%s: Context not started, state=%d\n",
+			__func__, ctx->state);
+		mutex_unlock(&ctx->state_mutex);
+		return VM_FAULT_SIGBUS;
+	}
+	mutex_unlock(&ctx->state_mutex);
+
 	mmio_area = ctx->psn_phys;
 	mmio_area += offset;
 
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index acd2801..1829e55 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -46,6 +46,12 @@ struct ocxl_hw_afu {
 	bool is_present;		/* Function has AFUs defined */
 };
 
+enum ocxlflash_ctx_state {
+	CLOSED,
+	OPENED,
+	STARTED
+};
+
 struct ocxlflash_context {
 	struct ocxl_hw_afu *hw_afu;	/* HW AFU back pointer */
 	struct address_space *mapping;	/* Mapping for pseudo filesystem */
@@ -57,6 +63,8 @@ struct ocxlflash_context {
 
 	spinlock_t slock;		/* Protects irq/fault/event updates */
 	wait_queue_head_t wq;		/* Wait queue for poll and interrupts */
+	struct mutex state_mutex;	/* Mutex to update context state */
+	enum ocxlflash_ctx_state state;	/* Context state */
 
 	struct ocxlflash_irqs *irqs;	/* Pointer to array of structures */
 	int num_irqs;			/* Number of interrupts */
-- 
2.1.0

[PATCH v3 36/41] cxlflash: Register for translation errors

[Uma Krishnan]

While enabling a context on the link, a predefined callback can be
registered with the OCXL provider services to be notified on translation
errors. These errors can in turn be passed back to the user on a read
operation.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 31 +++++++++++++++++++++++++++++--
 drivers/scsi/cxlflash/ocxl_hw.h |  4 ++++
 2 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 89d3d89..5b5565d 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -335,6 +335,25 @@ static u64 ocxlflash_get_irq_objhndl(void *ctx_cookie, int irq)
 }
 
 /**
+ * ocxlflash_xsl_fault() - callback when translation error is triggered
+ * @data:	Private data provided at callback registration, the context.
+ * @addr:	Address that triggered the error.
+ * @dsisr:	Value of dsisr register.
+ */
+static void ocxlflash_xsl_fault(void *data, u64 addr, u64 dsisr)
+{
+	struct ocxlflash_context *ctx = data;
+
+	spin_lock(&ctx->slock);
+	ctx->fault_addr = addr;
+	ctx->fault_dsisr = dsisr;
+	ctx->pending_fault = true;
+	spin_unlock(&ctx->slock);
+
+	wake_up_all(&ctx->wq);
+}
+
+/**
  * start_context() - local routine to start a context
  * @ctx:	Adapter context to be started.
  *
@@ -378,7 +397,8 @@ static int start_context(struct ocxlflash_context *ctx)
 		mm = current->mm;
 	}
 
-	rc = ocxl_link_add_pe(link_token, ctx->pe, pid, 0, 0, mm, NULL, NULL);
+	rc = ocxl_link_add_pe(link_token, ctx->pe, pid, 0, 0, mm,
+			      ocxlflash_xsl_fault, ctx);
 	if (unlikely(rc)) {
 		dev_err(dev, "%s: ocxl_link_add_pe failed rc=%d\n",
 			__func__, rc);
@@ -512,6 +532,7 @@ static void *ocxlflash_dev_context_init(struct pci_dev *pdev, void *afu_cookie)
 	ctx->hw_afu = afu;
 	ctx->irq_bitmap = 0;
 	ctx->pending_irq = false;
+	ctx->pending_fault = false;
 out:
 	return ctx;
 err2:
@@ -965,7 +986,7 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
  */
 static inline bool ctx_event_pending(struct ocxlflash_context *ctx)
 {
-	if (ctx->pending_irq)
+	if (ctx->pending_irq || ctx->pending_fault)
 		return true;
 
 	return false;
@@ -1070,6 +1091,12 @@ static ssize_t afu_read(struct file *file, char __user *buf, size_t count,
 		event.irq.irq = bit + 1;
 		if (bitmap_empty(&ctx->irq_bitmap, ctx->num_irqs))
 			ctx->pending_irq = false;
+	} else if (ctx->pending_fault) {
+		event.header.size += sizeof(struct cxl_event_data_storage);
+		event.header.type = CXL_EVENT_DATA_STORAGE;
+		event.fault.addr = ctx->fault_addr;
+		event.fault.dsisr = ctx->fault_dsisr;
+		ctx->pending_fault = false;
 	}
 
 	spin_unlock_irqrestore(&ctx->slock, lock_flags);
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index 1829e55..9270d35 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -70,4 +70,8 @@ struct ocxlflash_context {
 	int num_irqs;			/* Number of interrupts */
 	bool pending_irq;		/* Pending interrupt on the context */
 	ulong irq_bitmap;		/* Bits indicating pending irq num */
+
+	u64 fault_addr;			/* Address that triggered the fault */
+	u64 fault_dsisr;		/* Value of dsisr register at fault */
+	bool pending_fault;		/* Pending translation fault */
 };
-- 
2.1.0

[PATCH v3 36/41] cxlflash: Register for translation errors

[Uma Krishnan]

While enabling a context on the link, a predefined callback can be
registered with the OCXL provider services to be notified on translation
errors. These errors can in turn be passed back to the user on a read
operation.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 31 +++++++++++++++++++++++++++++--
 drivers/scsi/cxlflash/ocxl_hw.h |  4 ++++
 2 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 89d3d89..5b5565d 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -335,6 +335,25 @@ static u64 ocxlflash_get_irq_objhndl(void *ctx_cookie, int irq)
 }
 
 /**
+ * ocxlflash_xsl_fault() - callback when translation error is triggered
+ * @data:	Private data provided at callback registration, the context.
+ * @addr:	Address that triggered the error.
+ * @dsisr:	Value of dsisr register.
+ */
+static void ocxlflash_xsl_fault(void *data, u64 addr, u64 dsisr)
+{
+	struct ocxlflash_context *ctx = data;
+
+	spin_lock(&ctx->slock);
+	ctx->fault_addr = addr;
+	ctx->fault_dsisr = dsisr;
+	ctx->pending_fault = true;
+	spin_unlock(&ctx->slock);
+
+	wake_up_all(&ctx->wq);
+}
+
+/**
  * start_context() - local routine to start a context
  * @ctx:	Adapter context to be started.
  *
@@ -378,7 +397,8 @@ static int start_context(struct ocxlflash_context *ctx)
 		mm = current->mm;
 	}
 
-	rc = ocxl_link_add_pe(link_token, ctx->pe, pid, 0, 0, mm, NULL, NULL);
+	rc = ocxl_link_add_pe(link_token, ctx->pe, pid, 0, 0, mm,
+			      ocxlflash_xsl_fault, ctx);
 	if (unlikely(rc)) {
 		dev_err(dev, "%s: ocxl_link_add_pe failed rc=%d\n",
 			__func__, rc);
@@ -512,6 +532,7 @@ static void *ocxlflash_dev_context_init(struct pci_dev *pdev, void *afu_cookie)
 	ctx->hw_afu = afu;
 	ctx->irq_bitmap = 0;
 	ctx->pending_irq = false;
+	ctx->pending_fault = false;
 out:
 	return ctx;
 err2:
@@ -965,7 +986,7 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
  */
 static inline bool ctx_event_pending(struct ocxlflash_context *ctx)
 {
-	if (ctx->pending_irq)
+	if (ctx->pending_irq || ctx->pending_fault)
 		return true;
 
 	return false;
@@ -1070,6 +1091,12 @@ static ssize_t afu_read(struct file *file, char __user *buf, size_t count,
 		event.irq.irq = bit + 1;
 		if (bitmap_empty(&ctx->irq_bitmap, ctx->num_irqs))
 			ctx->pending_irq = false;
+	} else if (ctx->pending_fault) {
+		event.header.size += sizeof(struct cxl_event_data_storage);
+		event.header.type = CXL_EVENT_DATA_STORAGE;
+		event.fault.addr = ctx->fault_addr;
+		event.fault.dsisr = ctx->fault_dsisr;
+		ctx->pending_fault = false;
 	}
 
 	spin_unlock_irqrestore(&ctx->slock, lock_flags);
diff --git a/drivers/scsi/cxlflash/ocxl_hw.h b/drivers/scsi/cxlflash/ocxl_hw.h
index 1829e55..9270d35 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.h
+++ b/drivers/scsi/cxlflash/ocxl_hw.h
@@ -70,4 +70,8 @@ struct ocxlflash_context {
 	int num_irqs;			/* Number of interrupts */
 	bool pending_irq;		/* Pending interrupt on the context */
 	ulong irq_bitmap;		/* Bits indicating pending irq num */
+
+	u64 fault_addr;			/* Address that triggered the fault */
+	u64 fault_dsisr;		/* Value of dsisr register at fault */
+	bool pending_fault;		/* Pending translation fault */
 };
-- 
2.1.0

[PATCH v3 37/41] cxlflash: Support AFU reset

[Uma Krishnan]

The cxlflash core driver resets the AFU when the master contexts are
created in the initialization or recovery paths. Today, the OCXL
provider service to perform this operation is pending implementation.
To avoid a crash due to a missing fop, log an error once and return
success to continue with execution.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 5b5565d..0a95b5f 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -468,6 +468,22 @@ static int ocxlflash_stop_context(void *ctx_cookie)
 }
 
 /**
+ * ocxlflash_afu_reset() - reset the AFU
+ * @ctx_cookie:	Adapter context.
+ */
+static int ocxlflash_afu_reset(void *ctx_cookie)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+	struct device *dev = ctx->hw_afu->dev;
+
+	/* Pending implementation from OCXL transport services */
+	dev_err_once(dev, "%s: afu_reset() fop not supported\n", __func__);
+
+	/* Silently return success until it is implemented */
+	return 0;
+}
+
+/**
  * ocxlflash_set_master() - sets the context as master
  * @ctx_cookie:	Adapter context to set as master.
  */
@@ -1401,6 +1417,7 @@ const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.get_irq_objhndl	= ocxlflash_get_irq_objhndl,
 	.start_context		= ocxlflash_start_context,
 	.stop_context		= ocxlflash_stop_context,
+	.afu_reset		= ocxlflash_afu_reset,
 	.set_master		= ocxlflash_set_master,
 	.get_context		= ocxlflash_get_context,
 	.dev_context_init	= ocxlflash_dev_context_init,
-- 
2.1.0

[PATCH v3 37/41] cxlflash: Support AFU reset

[Uma Krishnan]

The cxlflash core driver resets the AFU when the master contexts are
created in the initialization or recovery paths. Today, the OCXL
provider service to perform this operation is pending implementation.
To avoid a crash due to a missing fop, log an error once and return
success to continue with execution.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/ocxl_hw.c | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index 5b5565d..0a95b5f 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -468,6 +468,22 @@ static int ocxlflash_stop_context(void *ctx_cookie)
 }
 
 /**
+ * ocxlflash_afu_reset() - reset the AFU
+ * @ctx_cookie:	Adapter context.
+ */
+static int ocxlflash_afu_reset(void *ctx_cookie)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+	struct device *dev = ctx->hw_afu->dev;
+
+	/* Pending implementation from OCXL transport services */
+	dev_err_once(dev, "%s: afu_reset() fop not supported\n", __func__);
+
+	/* Silently return success until it is implemented */
+	return 0;
+}
+
+/**
  * ocxlflash_set_master() - sets the context as master
  * @ctx_cookie:	Adapter context to set as master.
  */
@@ -1401,6 +1417,7 @@ const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
 	.get_irq_objhndl	= ocxlflash_get_irq_objhndl,
 	.start_context		= ocxlflash_start_context,
 	.stop_context		= ocxlflash_stop_context,
+	.afu_reset		= ocxlflash_afu_reset,
 	.set_master		= ocxlflash_set_master,
 	.get_context		= ocxlflash_get_context,
 	.dev_context_init	= ocxlflash_dev_context_init,
-- 
2.1.0

[PATCH v3 38/41] cxlflash: Enable OCXL operations

[Uma Krishnan]

This commit enables the OCXL operations for the OCXL devices.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/main.c | 9 +++++++--
 drivers/scsi/cxlflash/main.h | 1 +
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c
index 8c55fcd..42a95b7 100644
--- a/drivers/scsi/cxlflash/main.c
+++ b/drivers/scsi/cxlflash/main.c
@@ -3168,7 +3168,8 @@ static struct dev_dependent_vals dev_corsa_vals = { CXLFLASH_MAX_SECTORS,
 static struct dev_dependent_vals dev_flash_gt_vals = { CXLFLASH_MAX_SECTORS,
 					CXLFLASH_NOTIFY_SHUTDOWN };
 static struct dev_dependent_vals dev_briard_vals = { CXLFLASH_MAX_SECTORS,
-					CXLFLASH_NOTIFY_SHUTDOWN };
+					(CXLFLASH_NOTIFY_SHUTDOWN |
+					CXLFLASH_OCXL_DEV) };
 
 /*
  * PCI device binding table
@@ -3679,9 +3680,13 @@ static int cxlflash_probe(struct pci_dev *pdev,
 
 	cfg->init_state = INIT_STATE_NONE;
 	cfg->dev = pdev;
-	cfg->ops = &cxlflash_cxl_ops;
 	cfg->cxl_fops = cxlflash_cxl_fops;
 
+	if (ddv->flags & CXLFLASH_OCXL_DEV)
+		cfg->ops = &cxlflash_ocxl_ops;
+	else
+		cfg->ops = &cxlflash_cxl_ops;
+
 	/*
 	 * Promoted LUNs move to the top of the LUN table. The rest stay on
 	 * the bottom half. The bottom half grows from the end (index = 255),
diff --git a/drivers/scsi/cxlflash/main.h b/drivers/scsi/cxlflash/main.h
index ba0108a..6f1be62 100644
--- a/drivers/scsi/cxlflash/main.h
+++ b/drivers/scsi/cxlflash/main.h
@@ -97,6 +97,7 @@ struct dev_dependent_vals {
 	u64 flags;
 #define CXLFLASH_NOTIFY_SHUTDOWN	0x0000000000000001ULL
 #define CXLFLASH_WWPN_VPD_REQUIRED	0x0000000000000002ULL
+#define CXLFLASH_OCXL_DEV		0x0000000000000004ULL
 };
 
 struct asyc_intr_info {
-- 
2.1.0

[PATCH v3 38/41] cxlflash: Enable OCXL operations

[Uma Krishnan]

This commit enables the OCXL operations for the OCXL devices.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/main.c | 9 +++++++--
 drivers/scsi/cxlflash/main.h | 1 +
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c
index 8c55fcd..42a95b7 100644
--- a/drivers/scsi/cxlflash/main.c
+++ b/drivers/scsi/cxlflash/main.c
@@ -3168,7 +3168,8 @@ static struct dev_dependent_vals dev_corsa_vals = { CXLFLASH_MAX_SECTORS,
 static struct dev_dependent_vals dev_flash_gt_vals = { CXLFLASH_MAX_SECTORS,
 					CXLFLASH_NOTIFY_SHUTDOWN };
 static struct dev_dependent_vals dev_briard_vals = { CXLFLASH_MAX_SECTORS,
-					CXLFLASH_NOTIFY_SHUTDOWN };
+					(CXLFLASH_NOTIFY_SHUTDOWN |
+					CXLFLASH_OCXL_DEV) };
 
 /*
  * PCI device binding table
@@ -3679,9 +3680,13 @@ static int cxlflash_probe(struct pci_dev *pdev,
 
 	cfg->init_state = INIT_STATE_NONE;
 	cfg->dev = pdev;
-	cfg->ops = &cxlflash_cxl_ops;
 	cfg->cxl_fops = cxlflash_cxl_fops;
 
+	if (ddv->flags & CXLFLASH_OCXL_DEV)
+		cfg->ops = &cxlflash_ocxl_ops;
+	else
+		cfg->ops = &cxlflash_cxl_ops;
+
 	/*
 	 * Promoted LUNs move to the top of the LUN table. The rest stay on
 	 * the bottom half. The bottom half grows from the end (index = 255),
diff --git a/drivers/scsi/cxlflash/main.h b/drivers/scsi/cxlflash/main.h
index ba0108a..6f1be62 100644
--- a/drivers/scsi/cxlflash/main.h
+++ b/drivers/scsi/cxlflash/main.h
@@ -97,6 +97,7 @@ struct dev_dependent_vals {
 	u64 flags;
 #define CXLFLASH_NOTIFY_SHUTDOWN	0x0000000000000001ULL
 #define CXLFLASH_WWPN_VPD_REQUIRED	0x0000000000000002ULL
+#define CXLFLASH_OCXL_DEV		0x0000000000000004ULL
 };
 
 struct asyc_intr_info {
-- 
2.1.0

[PATCH v3 39/41] cxlflash: Synchronize reset and remove ops

[Uma Krishnan]

The following Oops can be encountered if a device removal or system
shutdown is initiated while an EEH recovery is in process:

[c000000ff2f479c0] c008000015256f18 cxlflash_pci_slot_reset+0xa0/0x100
                                      [cxlflash]
[c000000ff2f47a30] c00800000dae22e0 cxl_pci_slot_reset+0x168/0x290 [cxl]
[c000000ff2f47ae0] c00000000003ef1c eeh_report_reset+0xec/0x170
[c000000ff2f47b20] c00000000003d0b8 eeh_pe_dev_traverse+0x98/0x170
[c000000ff2f47bb0] c00000000003f80c eeh_handle_normal_event+0x56c/0x580
[c000000ff2f47c60] c00000000003fba4 eeh_handle_event+0x2a4/0x338
[c000000ff2f47d10] c0000000000400b8 eeh_event_handler+0x1f8/0x200
[c000000ff2f47dc0] c00000000013da48 kthread+0x1a8/0x1b0
[c000000ff2f47e30] c00000000000b528 ret_from_kernel_thread+0x5c/0xb4

The remove handler frees AFU memory while the EEH recovery is in progress,
leading to a race condition. This can result in a crash if the recovery
thread tries to access this memory.

To resolve this issue, the cxlflash remove handler will evaluate the
device state and yield to any active reset or probing threads.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/main.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c
index 42a95b7..dfe7648 100644
--- a/drivers/scsi/cxlflash/main.c
+++ b/drivers/scsi/cxlflash/main.c
@@ -946,9 +946,9 @@ static void cxlflash_remove(struct pci_dev *pdev)
 		return;
 	}
 
-	/* If a Task Management Function is active, wait for it to complete
-	 * before continuing with remove.
-	 */
+	/* Yield to running recovery threads before continuing with remove */
+	wait_event(cfg->reset_waitq, cfg->state != STATE_RESET &&
+				     cfg->state != STATE_PROBING);
 	spin_lock_irqsave(&cfg->tmf_slock, lock_flags);
 	if (cfg->tmf_active)
 		wait_event_interruptible_lock_irq(cfg->tmf_waitq,
-- 
2.1.0

[PATCH v3 39/41] cxlflash: Synchronize reset and remove ops

[Uma Krishnan]

The following Oops can be encountered if a device removal or system
shutdown is initiated while an EEH recovery is in process:

[c000000ff2f479c0] c008000015256f18 cxlflash_pci_slot_reset+0xa0/0x100
                                      [cxlflash]
[c000000ff2f47a30] c00800000dae22e0 cxl_pci_slot_reset+0x168/0x290 [cxl]
[c000000ff2f47ae0] c00000000003ef1c eeh_report_reset+0xec/0x170
[c000000ff2f47b20] c00000000003d0b8 eeh_pe_dev_traverse+0x98/0x170
[c000000ff2f47bb0] c00000000003f80c eeh_handle_normal_event+0x56c/0x580
[c000000ff2f47c60] c00000000003fba4 eeh_handle_event+0x2a4/0x338
[c000000ff2f47d10] c0000000000400b8 eeh_event_handler+0x1f8/0x200
[c000000ff2f47dc0] c00000000013da48 kthread+0x1a8/0x1b0
[c000000ff2f47e30] c00000000000b528 ret_from_kernel_thread+0x5c/0xb4

The remove handler frees AFU memory while the EEH recovery is in progress,
leading to a race condition. This can result in a crash if the recovery
thread tries to access this memory.

To resolve this issue, the cxlflash remove handler will evaluate the
device state and yield to any active reset or probing threads.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/main.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c
index 42a95b7..dfe7648 100644
--- a/drivers/scsi/cxlflash/main.c
+++ b/drivers/scsi/cxlflash/main.c
@@ -946,9 +946,9 @@ static void cxlflash_remove(struct pci_dev *pdev)
 		return;
 	}
 
-	/* If a Task Management Function is active, wait for it to complete
-	 * before continuing with remove.
-	 */
+	/* Yield to running recovery threads before continuing with remove */
+	wait_event(cfg->reset_waitq, cfg->state != STATE_RESET &&
+				     cfg->state != STATE_PROBING);
 	spin_lock_irqsave(&cfg->tmf_slock, lock_flags);
 	if (cfg->tmf_active)
 		wait_event_interruptible_lock_irq(cfg->tmf_waitq,
-- 
2.1.0

[PATCH v3 40/41] cxlflash: Remove commmands from pending list on timeout

[Uma Krishnan]

The following Oops can occur if an internal command sent to the AFU does
not complete within the timeout:

[c000000ff101b810] c008000016020d94 term_mc+0xfc/0x1b0 [cxlflash]
[c000000ff101b8a0] c008000016020fb0 term_afu+0x168/0x280 [cxlflash]
[c000000ff101b930] c0080000160232ec cxlflash_pci_error_detected+0x184/0x230
                                       [cxlflash]
[c000000ff101b9e0] c00800000d95d468 cxl_vphb_error_detected+0x90/0x150[cxl]
[c000000ff101ba20] c00800000d95f27c cxl_pci_error_detected+0xa4/0x240 [cxl]
[c000000ff101bac0] c00000000003eaf8 eeh_report_error+0xd8/0x1b0
[c000000ff101bb20] c00000000003d0b8 eeh_pe_dev_traverse+0x98/0x170
[c000000ff101bbb0] c00000000003f438 eeh_handle_normal_event+0x198/0x580
[c000000ff101bc60] c00000000003fba4 eeh_handle_event+0x2a4/0x338
[c000000ff101bd10] c0000000000400b8 eeh_event_handler+0x1f8/0x200
[c000000ff101bdc0] c00000000013da48 kthread+0x1a8/0x1b0
[c000000ff101be30] c00000000000b528 ret_from_kernel_thread+0x5c/0xb4

When an internal command times out, the command buffer is freed while it
is still in the pending commands list of the context. This corrupts the
list and when the context is cleaned up, a crash is encountered.

To resolve this issue, when an AFU command or TMF command times out, the
command should be deleted from the hardware queue pending command list
before freeing the buffer.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/main.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c
index dfe7648..c920328 100644
--- a/drivers/scsi/cxlflash/main.c
+++ b/drivers/scsi/cxlflash/main.c
@@ -473,6 +473,7 @@ static int send_tmf(struct cxlflash_cfg *cfg, struct scsi_device *sdev,
 	struct afu_cmd *cmd = NULL;
 	struct device *dev = &cfg->dev->dev;
 	struct hwq *hwq = get_hwq(afu, PRIMARY_HWQ);
+	bool needs_deletion = false;
 	char *buf = NULL;
 	ulong lock_flags;
 	int rc = 0;
@@ -527,6 +528,7 @@ static int send_tmf(struct cxlflash_cfg *cfg, struct scsi_device *sdev,
 	if (!to) {
 		dev_err(dev, "%s: TMF timed out\n", __func__);
 		rc = -ETIMEDOUT;
+		needs_deletion = true;
 	} else if (cmd->cmd_aborted) {
 		dev_err(dev, "%s: TMF aborted\n", __func__);
 		rc = -EAGAIN;
@@ -537,6 +539,12 @@ static int send_tmf(struct cxlflash_cfg *cfg, struct scsi_device *sdev,
 	}
 	cfg->tmf_active = false;
 	spin_unlock_irqrestore(&cfg->tmf_slock, lock_flags);
+
+	if (needs_deletion) {
+		spin_lock_irqsave(&hwq->hsq_slock, lock_flags);
+		list_del(&cmd->list);
+		spin_unlock_irqrestore(&hwq->hsq_slock, lock_flags);
+	}
 out:
 	kfree(buf);
 	return rc;
@@ -2284,6 +2292,7 @@ static int send_afu_cmd(struct afu *afu, struct sisl_ioarcb *rcb)
 	struct device *dev = &cfg->dev->dev;
 	struct afu_cmd *cmd = NULL;
 	struct hwq *hwq = get_hwq(afu, PRIMARY_HWQ);
+	ulong lock_flags;
 	char *buf = NULL;
 	int rc = 0;
 	int nretry = 0;
@@ -2329,6 +2338,11 @@ static int send_afu_cmd(struct afu *afu, struct sisl_ioarcb *rcb)
 	case -ETIMEDOUT:
 		rc = afu->context_reset(hwq);
 		if (rc) {
+			/* Delete the command from pending_cmds list */
+			spin_lock_irqsave(&hwq->hsq_slock, lock_flags);
+			list_del(&cmd->list);
+			spin_unlock_irqrestore(&hwq->hsq_slock, lock_flags);
+
 			cxlflash_schedule_async_reset(cfg);
 			break;
 		}
-- 
2.1.0

[PATCH v3 40/41] cxlflash: Remove commmands from pending list on timeout

[Uma Krishnan]

The following Oops can occur if an internal command sent to the AFU does
not complete within the timeout:

[c000000ff101b810] c008000016020d94 term_mc+0xfc/0x1b0 [cxlflash]
[c000000ff101b8a0] c008000016020fb0 term_afu+0x168/0x280 [cxlflash]
[c000000ff101b930] c0080000160232ec cxlflash_pci_error_detected+0x184/0x230
                                       [cxlflash]
[c000000ff101b9e0] c00800000d95d468 cxl_vphb_error_detected+0x90/0x150[cxl]
[c000000ff101ba20] c00800000d95f27c cxl_pci_error_detected+0xa4/0x240 [cxl]
[c000000ff101bac0] c00000000003eaf8 eeh_report_error+0xd8/0x1b0
[c000000ff101bb20] c00000000003d0b8 eeh_pe_dev_traverse+0x98/0x170
[c000000ff101bbb0] c00000000003f438 eeh_handle_normal_event+0x198/0x580
[c000000ff101bc60] c00000000003fba4 eeh_handle_event+0x2a4/0x338
[c000000ff101bd10] c0000000000400b8 eeh_event_handler+0x1f8/0x200
[c000000ff101bdc0] c00000000013da48 kthread+0x1a8/0x1b0
[c000000ff101be30] c00000000000b528 ret_from_kernel_thread+0x5c/0xb4

When an internal command times out, the command buffer is freed while it
is still in the pending commands list of the context. This corrupts the
list and when the context is cleaned up, a crash is encountered.

To resolve this issue, when an AFU command or TMF command times out, the
command should be deleted from the hardware queue pending command list
before freeing the buffer.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/main.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c
index dfe7648..c920328 100644
--- a/drivers/scsi/cxlflash/main.c
+++ b/drivers/scsi/cxlflash/main.c
@@ -473,6 +473,7 @@ static int send_tmf(struct cxlflash_cfg *cfg, struct scsi_device *sdev,
 	struct afu_cmd *cmd = NULL;
 	struct device *dev = &cfg->dev->dev;
 	struct hwq *hwq = get_hwq(afu, PRIMARY_HWQ);
+	bool needs_deletion = false;
 	char *buf = NULL;
 	ulong lock_flags;
 	int rc = 0;
@@ -527,6 +528,7 @@ static int send_tmf(struct cxlflash_cfg *cfg, struct scsi_device *sdev,
 	if (!to) {
 		dev_err(dev, "%s: TMF timed out\n", __func__);
 		rc = -ETIMEDOUT;
+		needs_deletion = true;
 	} else if (cmd->cmd_aborted) {
 		dev_err(dev, "%s: TMF aborted\n", __func__);
 		rc = -EAGAIN;
@@ -537,6 +539,12 @@ static int send_tmf(struct cxlflash_cfg *cfg, struct scsi_device *sdev,
 	}
 	cfg->tmf_active = false;
 	spin_unlock_irqrestore(&cfg->tmf_slock, lock_flags);
+
+	if (needs_deletion) {
+		spin_lock_irqsave(&hwq->hsq_slock, lock_flags);
+		list_del(&cmd->list);
+		spin_unlock_irqrestore(&hwq->hsq_slock, lock_flags);
+	}
 out:
 	kfree(buf);
 	return rc;
@@ -2284,6 +2292,7 @@ static int send_afu_cmd(struct afu *afu, struct sisl_ioarcb *rcb)
 	struct device *dev = &cfg->dev->dev;
 	struct afu_cmd *cmd = NULL;
 	struct hwq *hwq = get_hwq(afu, PRIMARY_HWQ);
+	ulong lock_flags;
 	char *buf = NULL;
 	int rc = 0;
 	int nretry = 0;
@@ -2329,6 +2338,11 @@ static int send_afu_cmd(struct afu *afu, struct sisl_ioarcb *rcb)
 	case -ETIMEDOUT:
 		rc = afu->context_reset(hwq);
 		if (rc) {
+			/* Delete the command from pending_cmds list */
+			spin_lock_irqsave(&hwq->hsq_slock, lock_flags);
+			list_del(&cmd->list);
+			spin_unlock_irqrestore(&hwq->hsq_slock, lock_flags);
+
 			cxlflash_schedule_async_reset(cfg);
 			break;
 		}
-- 
2.1.0

[PATCH v3 41/41] cxlflash: Handle spurious interrupts

[Uma Krishnan]

The following Oops can occur when there is heavy I/O traffic and the host
is reset by a tool such as sg_reset.

[c000200fff3fbc90] c00800001690117c process_cmd_doneq+0x104/0x500
                                       [cxlflash] (unreliable)
[c000200fff3fbd80] c008000016901648 cxlflash_rrq_irq+0xd0/0x150 [cxlflash]
[c000200fff3fbde0] c000000000193130 __handle_irq_event_percpu+0xa0/0x310
[c000200fff3fbea0] c0000000001933d8 handle_irq_event_percpu+0x38/0x90
[c000200fff3fbee0] c000000000193494 handle_irq_event+0x64/0xb0
[c000200fff3fbf10] c000000000198ea0 handle_fasteoi_irq+0xc0/0x230
[c000200fff3fbf40] c00000000019182c generic_handle_irq+0x4c/0x70
[c000200fff3fbf60] c00000000001794c __do_irq+0x7c/0x1c0
[c000200fff3fbf90] c00000000002a390 call_do_irq+0x14/0x24
[c000200e5828fab0] c000000000017b2c do_IRQ+0x9c/0x130
[c000200e5828fb00] c000000000009b04 h_virt_irq_common+0x114/0x120

When a context is reset, the pending commands are flushed and the AFU
is notified. Before the AFU handles this request there could be command
completion interrupts queued to PHB which are yet to be delivered to the
context. In this scenario, a context could receive an interrupt for a
command that has been flushed, leading to a possible crash when the memory
for the flushed command is accessed.

To resolve this problem, a boolean will indicate if the hardware queue is
ready to process interrupts or not. This can be evaluated in the interrupt
handler before proessing an interrupt.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/common.h |  1 +
 drivers/scsi/cxlflash/main.c   | 11 +++++++++++
 2 files changed, 12 insertions(+)

diff --git a/drivers/scsi/cxlflash/common.h b/drivers/scsi/cxlflash/common.h
index b69fd32..3556b1d 100644
--- a/drivers/scsi/cxlflash/common.h
+++ b/drivers/scsi/cxlflash/common.h
@@ -224,6 +224,7 @@ struct hwq {
 	u64 *hrrq_end;
 	u64 *hrrq_curr;
 	bool toggle;
+	bool hrrq_online;
 
 	s64 room;
 
diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c
index c920328..a24d7e6 100644
--- a/drivers/scsi/cxlflash/main.c
+++ b/drivers/scsi/cxlflash/main.c
@@ -801,6 +801,10 @@ static void term_mc(struct cxlflash_cfg *cfg, u32 index)
 		WARN_ON(cfg->ops->release_context(hwq->ctx_cookie));
 	hwq->ctx_cookie = NULL;
 
+	spin_lock_irqsave(&hwq->hrrq_slock, lock_flags);
+	hwq->hrrq_online = false;
+	spin_unlock_irqrestore(&hwq->hrrq_slock, lock_flags);
+
 	spin_lock_irqsave(&hwq->hsq_slock, lock_flags);
 	flush_pending_cmds(hwq);
 	spin_unlock_irqrestore(&hwq->hsq_slock, lock_flags);
@@ -1475,6 +1479,12 @@ static irqreturn_t cxlflash_rrq_irq(int irq, void *data)
 
 	spin_lock_irqsave(&hwq->hrrq_slock, hrrq_flags);
 
+	/* Silently drop spurious interrupts when queue is not online */
+	if (!hwq->hrrq_online) {
+		spin_unlock_irqrestore(&hwq->hrrq_slock, hrrq_flags);
+		return IRQ_HANDLED;
+	}
+
 	if (afu_is_irqpoll_enabled(afu)) {
 		irq_poll_sched(&hwq->irqpoll);
 		spin_unlock_irqrestore(&hwq->hrrq_slock, hrrq_flags);
@@ -1781,6 +1791,7 @@ static int init_global(struct cxlflash_cfg *cfg)
 
 		writeq_be((u64) hwq->hrrq_start, &hmap->rrq_start);
 		writeq_be((u64) hwq->hrrq_end, &hmap->rrq_end);
+		hwq->hrrq_online = true;
 
 		if (afu_is_sq_cmd_mode(afu)) {
 			writeq_be((u64)hwq->hsq_start, &hmap->sq_start);
-- 
2.1.0

[PATCH v3 41/41] cxlflash: Handle spurious interrupts

[Uma Krishnan]

The following Oops can occur when there is heavy I/O traffic and the host
is reset by a tool such as sg_reset.

[c000200fff3fbc90] c00800001690117c process_cmd_doneq+0x104/0x500
                                       [cxlflash] (unreliable)
[c000200fff3fbd80] c008000016901648 cxlflash_rrq_irq+0xd0/0x150 [cxlflash]
[c000200fff3fbde0] c000000000193130 __handle_irq_event_percpu+0xa0/0x310
[c000200fff3fbea0] c0000000001933d8 handle_irq_event_percpu+0x38/0x90
[c000200fff3fbee0] c000000000193494 handle_irq_event+0x64/0xb0
[c000200fff3fbf10] c000000000198ea0 handle_fasteoi_irq+0xc0/0x230
[c000200fff3fbf40] c00000000019182c generic_handle_irq+0x4c/0x70
[c000200fff3fbf60] c00000000001794c __do_irq+0x7c/0x1c0
[c000200fff3fbf90] c00000000002a390 call_do_irq+0x14/0x24
[c000200e5828fab0] c000000000017b2c do_IRQ+0x9c/0x130
[c000200e5828fb00] c000000000009b04 h_virt_irq_common+0x114/0x120

When a context is reset, the pending commands are flushed and the AFU
is notified. Before the AFU handles this request there could be command
completion interrupts queued to PHB which are yet to be delivered to the
context. In this scenario, a context could receive an interrupt for a
command that has been flushed, leading to a possible crash when the memory
for the flushed command is accessed.

To resolve this problem, a boolean will indicate if the hardware queue is
ready to process interrupts or not. This can be evaluated in the interrupt
handler before proessing an interrupt.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/common.h |  1 +
 drivers/scsi/cxlflash/main.c   | 11 +++++++++++
 2 files changed, 12 insertions(+)

diff --git a/drivers/scsi/cxlflash/common.h b/drivers/scsi/cxlflash/common.h
index b69fd32..3556b1d 100644
--- a/drivers/scsi/cxlflash/common.h
+++ b/drivers/scsi/cxlflash/common.h
@@ -224,6 +224,7 @@ struct hwq {
 	u64 *hrrq_end;
 	u64 *hrrq_curr;
 	bool toggle;
+	bool hrrq_online;
 
 	s64 room;
 
diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c
index c920328..a24d7e6 100644
--- a/drivers/scsi/cxlflash/main.c
+++ b/drivers/scsi/cxlflash/main.c
@@ -801,6 +801,10 @@ static void term_mc(struct cxlflash_cfg *cfg, u32 index)
 		WARN_ON(cfg->ops->release_context(hwq->ctx_cookie));
 	hwq->ctx_cookie = NULL;
 
+	spin_lock_irqsave(&hwq->hrrq_slock, lock_flags);
+	hwq->hrrq_online = false;
+	spin_unlock_irqrestore(&hwq->hrrq_slock, lock_flags);
+
 	spin_lock_irqsave(&hwq->hsq_slock, lock_flags);
 	flush_pending_cmds(hwq);
 	spin_unlock_irqrestore(&hwq->hsq_slock, lock_flags);
@@ -1475,6 +1479,12 @@ static irqreturn_t cxlflash_rrq_irq(int irq, void *data)
 
 	spin_lock_irqsave(&hwq->hrrq_slock, hrrq_flags);
 
+	/* Silently drop spurious interrupts when queue is not online */
+	if (!hwq->hrrq_online) {
+		spin_unlock_irqrestore(&hwq->hrrq_slock, hrrq_flags);
+		return IRQ_HANDLED;
+	}
+
 	if (afu_is_irqpoll_enabled(afu)) {
 		irq_poll_sched(&hwq->irqpoll);
 		spin_unlock_irqrestore(&hwq->hrrq_slock, hrrq_flags);
@@ -1781,6 +1791,7 @@ static int init_global(struct cxlflash_cfg *cfg)
 
 		writeq_be((u64) hwq->hrrq_start, &hmap->rrq_start);
 		writeq_be((u64) hwq->hrrq_end, &hmap->rrq_end);
+		hwq->hrrq_online = true;
 
 		if (afu_is_sq_cmd_mode(afu)) {
 			writeq_be((u64)hwq->hsq_start, &hmap->sq_start);
-- 
2.1.0

Re: [PATCH v3 39/41] cxlflash: Synchronize reset and remove ops

[Matthew R. Ochs]

On Mon, Mar 26, 2018 at 11:35:27AM -0500, Uma Krishnan wrote:
> The following Oops can be encountered if a device removal or system
> shutdown is initiated while an EEH recovery is in process:
> 
> [c000000ff2f479c0] c008000015256f18 cxlflash_pci_slot_reset+0xa0/0x100
>                                       [cxlflash]
> [c000000ff2f47a30] c00800000dae22e0 cxl_pci_slot_reset+0x168/0x290 [cxl]
> [c000000ff2f47ae0] c00000000003ef1c eeh_report_reset+0xec/0x170
> [c000000ff2f47b20] c00000000003d0b8 eeh_pe_dev_traverse+0x98/0x170
> [c000000ff2f47bb0] c00000000003f80c eeh_handle_normal_event+0x56c/0x580
> [c000000ff2f47c60] c00000000003fba4 eeh_handle_event+0x2a4/0x338
> [c000000ff2f47d10] c0000000000400b8 eeh_event_handler+0x1f8/0x200
> [c000000ff2f47dc0] c00000000013da48 kthread+0x1a8/0x1b0
> [c000000ff2f47e30] c00000000000b528 ret_from_kernel_thread+0x5c/0xb4
> 
> The remove handler frees AFU memory while the EEH recovery is in progress,
> leading to a race condition. This can result in a crash if the recovery
> thread tries to access this memory.
> 
> To resolve this issue, the cxlflash remove handler will evaluate the
> device state and yield to any active reset or probing threads.
> 
> Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>

Looks good!

Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>

Re: [PATCH v3 39/41] cxlflash: Synchronize reset and remove ops

[Matthew R. Ochs]

On Mon, Mar 26, 2018 at 11:35:27AM -0500, Uma Krishnan wrote:
> The following Oops can be encountered if a device removal or system
> shutdown is initiated while an EEH recovery is in process:
> 
> [c000000ff2f479c0] c008000015256f18 cxlflash_pci_slot_reset+0xa0/0x100
>                                       [cxlflash]
> [c000000ff2f47a30] c00800000dae22e0 cxl_pci_slot_reset+0x168/0x290 [cxl]
> [c000000ff2f47ae0] c00000000003ef1c eeh_report_reset+0xec/0x170
> [c000000ff2f47b20] c00000000003d0b8 eeh_pe_dev_traverse+0x98/0x170
> [c000000ff2f47bb0] c00000000003f80c eeh_handle_normal_event+0x56c/0x580
> [c000000ff2f47c60] c00000000003fba4 eeh_handle_event+0x2a4/0x338
> [c000000ff2f47d10] c0000000000400b8 eeh_event_handler+0x1f8/0x200
> [c000000ff2f47dc0] c00000000013da48 kthread+0x1a8/0x1b0
> [c000000ff2f47e30] c00000000000b528 ret_from_kernel_thread+0x5c/0xb4
> 
> The remove handler frees AFU memory while the EEH recovery is in progress,
> leading to a race condition. This can result in a crash if the recovery
> thread tries to access this memory.
> 
> To resolve this issue, the cxlflash remove handler will evaluate the
> device state and yield to any active reset or probing threads.
> 
> Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>

Looks good!

Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>

Re: [PATCH v3 40/41] cxlflash: Remove commmands from pending list on timeout

[Matthew R. Ochs]

On Mon, Mar 26, 2018 at 11:35:34AM -0500, Uma Krishnan wrote:
> The following Oops can occur if an internal command sent to the AFU does
> not complete within the timeout:
> 
> [c000000ff101b810] c008000016020d94 term_mc+0xfc/0x1b0 [cxlflash]
> [c000000ff101b8a0] c008000016020fb0 term_afu+0x168/0x280 [cxlflash]
> [c000000ff101b930] c0080000160232ec cxlflash_pci_error_detected+0x184/0x230
>                                        [cxlflash]
> [c000000ff101b9e0] c00800000d95d468 cxl_vphb_error_detected+0x90/0x150[cxl]
> [c000000ff101ba20] c00800000d95f27c cxl_pci_error_detected+0xa4/0x240 [cxl]
> [c000000ff101bac0] c00000000003eaf8 eeh_report_error+0xd8/0x1b0
> [c000000ff101bb20] c00000000003d0b8 eeh_pe_dev_traverse+0x98/0x170
> [c000000ff101bbb0] c00000000003f438 eeh_handle_normal_event+0x198/0x580
> [c000000ff101bc60] c00000000003fba4 eeh_handle_event+0x2a4/0x338
> [c000000ff101bd10] c0000000000400b8 eeh_event_handler+0x1f8/0x200
> [c000000ff101bdc0] c00000000013da48 kthread+0x1a8/0x1b0
> [c000000ff101be30] c00000000000b528 ret_from_kernel_thread+0x5c/0xb4
> 
> When an internal command times out, the command buffer is freed while it
> is still in the pending commands list of the context. This corrupts the
> list and when the context is cleaned up, a crash is encountered.
> 
> To resolve this issue, when an AFU command or TMF command times out, the
> command should be deleted from the hardware queue pending command list
> before freeing the buffer.
> 
> Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>

Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>

Re: [PATCH v3 40/41] cxlflash: Remove commmands from pending list on timeout

[Matthew R. Ochs]

On Mon, Mar 26, 2018 at 11:35:34AM -0500, Uma Krishnan wrote:
> The following Oops can occur if an internal command sent to the AFU does
> not complete within the timeout:
> 
> [c000000ff101b810] c008000016020d94 term_mc+0xfc/0x1b0 [cxlflash]
> [c000000ff101b8a0] c008000016020fb0 term_afu+0x168/0x280 [cxlflash]
> [c000000ff101b930] c0080000160232ec cxlflash_pci_error_detected+0x184/0x230
>                                        [cxlflash]
> [c000000ff101b9e0] c00800000d95d468 cxl_vphb_error_detected+0x90/0x150[cxl]
> [c000000ff101ba20] c00800000d95f27c cxl_pci_error_detected+0xa4/0x240 [cxl]
> [c000000ff101bac0] c00000000003eaf8 eeh_report_error+0xd8/0x1b0
> [c000000ff101bb20] c00000000003d0b8 eeh_pe_dev_traverse+0x98/0x170
> [c000000ff101bbb0] c00000000003f438 eeh_handle_normal_event+0x198/0x580
> [c000000ff101bc60] c00000000003fba4 eeh_handle_event+0x2a4/0x338
> [c000000ff101bd10] c0000000000400b8 eeh_event_handler+0x1f8/0x200
> [c000000ff101bdc0] c00000000013da48 kthread+0x1a8/0x1b0
> [c000000ff101be30] c00000000000b528 ret_from_kernel_thread+0x5c/0xb4
> 
> When an internal command times out, the command buffer is freed while it
> is still in the pending commands list of the context. This corrupts the
> list and when the context is cleaned up, a crash is encountered.
> 
> To resolve this issue, when an AFU command or TMF command times out, the
> command should be deleted from the hardware queue pending command list
> before freeing the buffer.
> 
> Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>

Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>

Re: [PATCH v3 41/41] cxlflash: Handle spurious interrupts

[Matthew R. Ochs]

On Mon, Mar 26, 2018 at 11:35:42AM -0500, Uma Krishnan wrote:
> The following Oops can occur when there is heavy I/O traffic and the host
> is reset by a tool such as sg_reset.
> 
> [c000200fff3fbc90] c00800001690117c process_cmd_doneq+0x104/0x500
>                                        [cxlflash] (unreliable)
> [c000200fff3fbd80] c008000016901648 cxlflash_rrq_irq+0xd0/0x150 [cxlflash]
> [c000200fff3fbde0] c000000000193130 __handle_irq_event_percpu+0xa0/0x310
> [c000200fff3fbea0] c0000000001933d8 handle_irq_event_percpu+0x38/0x90
> [c000200fff3fbee0] c000000000193494 handle_irq_event+0x64/0xb0
> [c000200fff3fbf10] c000000000198ea0 handle_fasteoi_irq+0xc0/0x230
> [c000200fff3fbf40] c00000000019182c generic_handle_irq+0x4c/0x70
> [c000200fff3fbf60] c00000000001794c __do_irq+0x7c/0x1c0
> [c000200fff3fbf90] c00000000002a390 call_do_irq+0x14/0x24
> [c000200e5828fab0] c000000000017b2c do_IRQ+0x9c/0x130
> [c000200e5828fb00] c000000000009b04 h_virt_irq_common+0x114/0x120
> 
> When a context is reset, the pending commands are flushed and the AFU
> is notified. Before the AFU handles this request there could be command
> completion interrupts queued to PHB which are yet to be delivered to the
> context. In this scenario, a context could receive an interrupt for a
> command that has been flushed, leading to a possible crash when the memory
> for the flushed command is accessed.
> 
> To resolve this problem, a boolean will indicate if the hardware queue is
> ready to process interrupts or not. This can be evaluated in the interrupt
> handler before proessing an interrupt.
> 
> Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>

Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>

Re: [PATCH v3 41/41] cxlflash: Handle spurious interrupts

[Matthew R. Ochs]

On Mon, Mar 26, 2018 at 11:35:42AM -0500, Uma Krishnan wrote:
> The following Oops can occur when there is heavy I/O traffic and the host
> is reset by a tool such as sg_reset.
> 
> [c000200fff3fbc90] c00800001690117c process_cmd_doneq+0x104/0x500
>                                        [cxlflash] (unreliable)
> [c000200fff3fbd80] c008000016901648 cxlflash_rrq_irq+0xd0/0x150 [cxlflash]
> [c000200fff3fbde0] c000000000193130 __handle_irq_event_percpu+0xa0/0x310
> [c000200fff3fbea0] c0000000001933d8 handle_irq_event_percpu+0x38/0x90
> [c000200fff3fbee0] c000000000193494 handle_irq_event+0x64/0xb0
> [c000200fff3fbf10] c000000000198ea0 handle_fasteoi_irq+0xc0/0x230
> [c000200fff3fbf40] c00000000019182c generic_handle_irq+0x4c/0x70
> [c000200fff3fbf60] c00000000001794c __do_irq+0x7c/0x1c0
> [c000200fff3fbf90] c00000000002a390 call_do_irq+0x14/0x24
> [c000200e5828fab0] c000000000017b2c do_IRQ+0x9c/0x130
> [c000200e5828fb00] c000000000009b04 h_virt_irq_common+0x114/0x120
> 
> When a context is reset, the pending commands are flushed and the AFU
> is notified. Before the AFU handles this request there could be command
> completion interrupts queued to PHB which are yet to be delivered to the
> context. In this scenario, a context could receive an interrupt for a
> command that has been flushed, leading to a possible crash when the memory
> for the flushed command is accessed.
> 
> To resolve this problem, a boolean will indicate if the hardware queue is
> ready to process interrupts or not. This can be evaluated in the interrupt
> handler before proessing an interrupt.
> 
> Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>

Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>

Re: [PATCH v3 00/41] cxlflash: OCXL transport support and miscellaneous fixes

[Martin K. Petersen]

Uma,

> This patch series adds OCXL support to the cxlflash driver. With this
> support, new devices using the OCXL transport will be supported by the
> cxlflash driver along with the existing CXL devices. An effort is made
> to keep this transport specific function independent of the existing
> core driver that communicates with the AFU.
>
> The first three patches contain a minor fix and staging improvements.
>
> This series is intended for 4.17 and is bisectable.

Something this big really needs to be submitted around rc2/rc3. It's way
too late in the cycle to ensure proper zeroday coverage for all these
commits.

I have started a 4.18/scsi-queue branch to hold this series for now.
The 4.18 branch will be rebased once 4.17rc1 is out in a few weeks. Your
changes won't show up in for-next until then either.

Thanks!

-- 
Martin K. Petersen	Oracle Linux Engineering

Re: [PATCH v3 00/41] cxlflash: OCXL transport support and miscellaneous fixes

[Martin K. Petersen]

Uma,

> This patch series adds OCXL support to the cxlflash driver. With this
> support, new devices using the OCXL transport will be supported by the
> cxlflash driver along with the existing CXL devices. An effort is made
> to keep this transport specific function independent of the existing
> core driver that communicates with the AFU.
>
> The first three patches contain a minor fix and staging improvements.
>
> This series is intended for 4.17 and is bisectable.

Something this big really needs to be submitted around rc2/rc3. It's way
too late in the cycle to ensure proper zeroday coverage for all these
commits.

I have started a 4.18/scsi-queue branch to hold this series for now.
The 4.18 branch will be rebased once 4.17rc1 is out in a few weeks. Your
changes won't show up in for-next until then either.

Thanks!

-- 
Martin K. Petersen	Oracle Linux Engineering

Re: [PATCH v3 00/41] cxlflash: OCXL transport support and miscellaneous fixes

[Uma Krishnan]

> On Mar 28, 2018, at 4:34 PM, Martin K. Petersen <martin.petersen@oracle.com> wrote:
> 
> 
> Uma,
> 
>> This patch series adds OCXL support to the cxlflash driver. With this
>> support, new devices using the OCXL transport will be supported by the
>> cxlflash driver along with the existing CXL devices. An effort is made
>> to keep this transport specific function independent of the existing
>> core driver that communicates with the AFU.
>> 
>> The first three patches contain a minor fix and staging improvements.
>> 
>> This series is intended for 4.17 and is bisectable.
> 
> Something this big really needs to be submitted around rc2/rc3. It's way
> too late in the cycle to ensure proper zeroday coverage for all these
> commits.
> 
> I have started a 4.18/scsi-queue branch to hold this series for now.
> The 4.18 branch will be rebased once 4.17rc1 is out in a few weeks. Your
> changes won't show up in for-next until then either.

I did send the first version of this series just after 4.16rc2 but the reviews took a while and the V3 is cutting close unless we do have an rc8 for 4.16 :)

I understand what you are saying and agree with you. Thanks for keeping me posted.

Re: [PATCH v3 00/41] cxlflash: OCXL transport support and miscellaneous fixes

[Uma Krishnan]

> On Mar 28, 2018, at 4:34 PM, Martin K. Petersen =
<martin.petersen@oracle.com> wrote:
>=20
>=20
> Uma,
>=20
>> This patch series adds OCXL support to the cxlflash driver. With this
>> support, new devices using the OCXL transport will be supported by =
the
>> cxlflash driver along with the existing CXL devices. An effort is =
made
>> to keep this transport specific function independent of the existing
>> core driver that communicates with the AFU.
>>=20
>> The first three patches contain a minor fix and staging improvements.
>>=20
>> This series is intended for 4.17 and is bisectable.
>=20
> Something this big really needs to be submitted around rc2/rc3. It's =
way
> too late in the cycle to ensure proper zeroday coverage for all these
> commits.
>=20
> I have started a 4.18/scsi-queue branch to hold this series for now.
> The 4.18 branch will be rebased once 4.17rc1 is out in a few weeks. =
Your
> changes won't show up in for-next until then either.

I did send the first version of this series just after 4.16rc2 but the =
reviews took a while and the V3 is cutting close unless we do have an =
rc8 for 4.16 :)

I understand what you are saying and agree with you. Thanks for keeping =
me posted.=