diff mbox series

[ndctl,v4,1/6] libcxl: add GET_PARTITION_INFO mailbox command and accessors

Message ID 396ccc39525b3eb829acd4e06f704f6fb57a94a8.1644271559.git.alison.schofield@intel.com (mailing list archive)
State Superseded
Headers show
Series Add partitioning support for CXL memdevs | expand

Commit Message

Alison Schofield Feb. 7, 2022, 11:10 p.m. UTC 
From: Alison Schofield <alison.schofield@intel.com>

Users need access to the CXL GET_PARTITION_INFO mailbox command
to inspect and confirm changes to the partition layout of a memory
device.

Add libcxl APIs to create a new GET_PARTITION_INFO mailbox command,
the command output data structure (privately), and accessor APIs to
return the different fields in the partition info output.

Per the CXL 2.0 specification, devices report partition capacities
as multiples of 256MB. Define and use a capacity multiplier to
convert the raw data into bytes for user consumption. Use byte
format as the norm for all capacity values produced or consumed
using CXL Mailbox commands.

Signed-off-by: Alison Schofield <alison.schofield@intel.com>
---
 Documentation/cxl/lib/libcxl.txt |  1 +
 cxl/lib/libcxl.c                 | 57 ++++++++++++++++++++++++++++++++
 cxl/lib/libcxl.sym               |  5 +++
 cxl/lib/private.h                | 10 ++++++
 cxl/libcxl.h                     |  5 +++
 util/size.h                      |  1 +
 6 files changed, 79 insertions(+)

Comments

Dan Williams Feb. 8, 2022, 8:20 p.m. UTC | #1 
On Mon, Feb 7, 2022 at 3:06 PM <alison.schofield@intel.com> wrote:
>
> From: Alison Schofield <alison.schofield@intel.com>
>
> Users need access to the CXL GET_PARTITION_INFO mailbox command
> to inspect and confirm changes to the partition layout of a memory
> device.
>
> Add libcxl APIs to create a new GET_PARTITION_INFO mailbox command,
> the command output data structure (privately), and accessor APIs to
> return the different fields in the partition info output.
>
> Per the CXL 2.0 specification, devices report partition capacities
> as multiples of 256MB. Define and use a capacity multiplier to
> convert the raw data into bytes for user consumption. Use byte
> format as the norm for all capacity values produced or consumed
> using CXL Mailbox commands.
>
> Signed-off-by: Alison Schofield <alison.schofield@intel.com>
> ---
>  Documentation/cxl/lib/libcxl.txt |  1 +
>  cxl/lib/libcxl.c                 | 57 ++++++++++++++++++++++++++++++++
>  cxl/lib/libcxl.sym               |  5 +++
>  cxl/lib/private.h                | 10 ++++++
>  cxl/libcxl.h                     |  5 +++
>  util/size.h                      |  1 +
>  6 files changed, 79 insertions(+)
>
> diff --git a/Documentation/cxl/lib/libcxl.txt b/Documentation/cxl/lib/libcxl.txt
> index 4392b47..a6986ab 100644
> --- a/Documentation/cxl/lib/libcxl.txt
> +++ b/Documentation/cxl/lib/libcxl.txt
> @@ -131,6 +131,7 @@ int cxl_memdev_read_label(struct cxl_memdev *memdev, void *buf, size_t length,
>                           size_t offset);
>  int cxl_memdev_write_label(struct cxl_memdev *memdev, void *buf, size_t length,
>                            size_t offset);
> +struct cxl_cmd *cxl_cmd_new_get_partition(struct cxl_memdev *memdev);
>
>  ----
>
> diff --git a/cxl/lib/libcxl.c b/cxl/lib/libcxl.c
> index e0b443f..33cf06b 100644
> --- a/cxl/lib/libcxl.c
> +++ b/cxl/lib/libcxl.c
> @@ -1985,6 +1985,12 @@ static int cxl_cmd_validate_status(struct cxl_cmd *cmd, u32 id)
>         return 0;
>  }
>
> +static unsigned long long
> +capacity_to_bytes(unsigned long long size)

If this helper converts an encoded le64 to bytes then the function
signature should reflect that:

static uint64_t cxl_capacity_to_bytes(leint64_t size)

> +{
> +       return le64_to_cpu(size) * CXL_CAPACITY_MULTIPLIER;
> +}
> +
>  /* Helpers for health_info fields (no endian conversion) */
>  #define cmd_get_field_u8(cmd, n, N, field)                             \
>  do {                                                                   \
> @@ -2371,6 +2377,57 @@ CXL_EXPORT ssize_t cxl_cmd_read_label_get_payload(struct cxl_cmd *cmd,
>         return length;
>  }
>
> +CXL_EXPORT struct cxl_cmd *cxl_cmd_new_get_partition(struct cxl_memdev *memdev)
> +{
> +       return cxl_cmd_new_generic(memdev,
> +                                  CXL_MEM_COMMAND_ID_GET_PARTITION_INFO);
> +}
> +
> +static struct cxl_cmd_get_partition *
> +cmd_to_get_partition(struct cxl_cmd *cmd)
> +{

This could also check for cmd == NULL just to be complete.

> +       if (cxl_cmd_validate_status(cmd, CXL_MEM_COMMAND_ID_GET_PARTITION_INFO))
> +               return NULL;
> +
> +       return cmd->output_payload;
> +}
> +
> +CXL_EXPORT unsigned long long
> +cxl_cmd_partition_get_active_volatile_size(struct cxl_cmd *cmd)
> +{
> +       struct cxl_cmd_get_partition *c;
> +
> +       c = cmd_to_get_partition(cmd);
> +       return c ? capacity_to_bytes(c->active_volatile) : ULLONG_MAX;

I'd prefer kernel coding style which wants:

if (!c)
    return ULLONG_MAX;
return cxl_capacity_to_bytes(c->active_volatile);

Otherwise, looks good to me:

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Alison Schofield Feb. 8, 2022, 8:46 p.m. UTC | #2 
Thanks Dan! Got it all.
<eom>

On Tue, Feb 08, 2022 at 12:20:56PM -0800, Dan Williams wrote:
> On Mon, Feb 7, 2022 at 3:06 PM <alison.schofield@intel.com> wrote:
> >
> > From: Alison Schofield <alison.schofield@intel.com>
> >
> > Users need access to the CXL GET_PARTITION_INFO mailbox command
> > to inspect and confirm changes to the partition layout of a memory
> > device.
> >
> > Add libcxl APIs to create a new GET_PARTITION_INFO mailbox command,
> > the command output data structure (privately), and accessor APIs to
> > return the different fields in the partition info output.
> >
> > Per the CXL 2.0 specification, devices report partition capacities
> > as multiples of 256MB. Define and use a capacity multiplier to
> > convert the raw data into bytes for user consumption. Use byte
> > format as the norm for all capacity values produced or consumed
> > using CXL Mailbox commands.
> >
> > Signed-off-by: Alison Schofield <alison.schofield@intel.com>
> > ---
> >  Documentation/cxl/lib/libcxl.txt |  1 +
> >  cxl/lib/libcxl.c                 | 57 ++++++++++++++++++++++++++++++++
> >  cxl/lib/libcxl.sym               |  5 +++
> >  cxl/lib/private.h                | 10 ++++++
> >  cxl/libcxl.h                     |  5 +++
> >  util/size.h                      |  1 +
> >  6 files changed, 79 insertions(+)
> >
> > diff --git a/Documentation/cxl/lib/libcxl.txt b/Documentation/cxl/lib/libcxl.txt
> > index 4392b47..a6986ab 100644
> > --- a/Documentation/cxl/lib/libcxl.txt
> > +++ b/Documentation/cxl/lib/libcxl.txt
> > @@ -131,6 +131,7 @@ int cxl_memdev_read_label(struct cxl_memdev *memdev, void *buf, size_t length,
> >                           size_t offset);
> >  int cxl_memdev_write_label(struct cxl_memdev *memdev, void *buf, size_t length,
> >                            size_t offset);
> > +struct cxl_cmd *cxl_cmd_new_get_partition(struct cxl_memdev *memdev);
> >
> >  ----
> >
> > diff --git a/cxl/lib/libcxl.c b/cxl/lib/libcxl.c
> > index e0b443f..33cf06b 100644
> > --- a/cxl/lib/libcxl.c
> > +++ b/cxl/lib/libcxl.c
> > @@ -1985,6 +1985,12 @@ static int cxl_cmd_validate_status(struct cxl_cmd *cmd, u32 id)
> >         return 0;
> >  }
> >
> > +static unsigned long long
> > +capacity_to_bytes(unsigned long long size)
> 
> If this helper converts an encoded le64 to bytes then the function
> signature should reflect that:
> 
> static uint64_t cxl_capacity_to_bytes(leint64_t size)
> 
> > +{
> > +       return le64_to_cpu(size) * CXL_CAPACITY_MULTIPLIER;
> > +}
> > +
> >  /* Helpers for health_info fields (no endian conversion) */
> >  #define cmd_get_field_u8(cmd, n, N, field)                             \
> >  do {                                                                   \
> > @@ -2371,6 +2377,57 @@ CXL_EXPORT ssize_t cxl_cmd_read_label_get_payload(struct cxl_cmd *cmd,
> >         return length;
> >  }
> >
> > +CXL_EXPORT struct cxl_cmd *cxl_cmd_new_get_partition(struct cxl_memdev *memdev)
> > +{
> > +       return cxl_cmd_new_generic(memdev,
> > +                                  CXL_MEM_COMMAND_ID_GET_PARTITION_INFO);
> > +}
> > +
> > +static struct cxl_cmd_get_partition *
> > +cmd_to_get_partition(struct cxl_cmd *cmd)
> > +{
> 
> This could also check for cmd == NULL just to be complete.
> 
> > +       if (cxl_cmd_validate_status(cmd, CXL_MEM_COMMAND_ID_GET_PARTITION_INFO))
> > +               return NULL;
> > +
> > +       return cmd->output_payload;
> > +}
> > +
> > +CXL_EXPORT unsigned long long
> > +cxl_cmd_partition_get_active_volatile_size(struct cxl_cmd *cmd)
> > +{
> > +       struct cxl_cmd_get_partition *c;
> > +
> > +       c = cmd_to_get_partition(cmd);
> > +       return c ? capacity_to_bytes(c->active_volatile) : ULLONG_MAX;
> 
> I'd prefer kernel coding style which wants:
> 
> if (!c)
>     return ULLONG_MAX;
> return cxl_capacity_to_bytes(c->active_volatile);
> 
> Otherwise, looks good to me:
> 
> Reviewed-by: Dan Williams <dan.j.williams@intel.com>
diff mbox series

Patch

diff --git a/Documentation/cxl/lib/libcxl.txt b/Documentation/cxl/lib/libcxl.txt
index 4392b47..a6986ab 100644
--- a/Documentation/cxl/lib/libcxl.txt
+++ b/Documentation/cxl/lib/libcxl.txt
@@ -131,6 +131,7 @@  int cxl_memdev_read_label(struct cxl_memdev *memdev, void *buf, size_t length,
 			  size_t offset);
 int cxl_memdev_write_label(struct cxl_memdev *memdev, void *buf, size_t length,
 			   size_t offset);
+struct cxl_cmd *cxl_cmd_new_get_partition(struct cxl_memdev *memdev);
 
 ----
 
diff --git a/cxl/lib/libcxl.c b/cxl/lib/libcxl.c
index e0b443f..33cf06b 100644
--- a/cxl/lib/libcxl.c
+++ b/cxl/lib/libcxl.c
@@ -1985,6 +1985,12 @@  static int cxl_cmd_validate_status(struct cxl_cmd *cmd, u32 id)
 	return 0;
 }
 
+static unsigned long long
+capacity_to_bytes(unsigned long long size)
+{
+	return le64_to_cpu(size) * CXL_CAPACITY_MULTIPLIER;
+}
+
 /* Helpers for health_info fields (no endian conversion) */
 #define cmd_get_field_u8(cmd, n, N, field)				\
 do {									\
@@ -2371,6 +2377,57 @@  CXL_EXPORT ssize_t cxl_cmd_read_label_get_payload(struct cxl_cmd *cmd,
 	return length;
 }
 
+CXL_EXPORT struct cxl_cmd *cxl_cmd_new_get_partition(struct cxl_memdev *memdev)
+{
+	return cxl_cmd_new_generic(memdev,
+				   CXL_MEM_COMMAND_ID_GET_PARTITION_INFO);
+}
+
+static struct cxl_cmd_get_partition *
+cmd_to_get_partition(struct cxl_cmd *cmd)
+{
+	if (cxl_cmd_validate_status(cmd, CXL_MEM_COMMAND_ID_GET_PARTITION_INFO))
+		return NULL;
+
+	return cmd->output_payload;
+}
+
+CXL_EXPORT unsigned long long
+cxl_cmd_partition_get_active_volatile_size(struct cxl_cmd *cmd)
+{
+	struct cxl_cmd_get_partition *c;
+
+	c = cmd_to_get_partition(cmd);
+	return c ? capacity_to_bytes(c->active_volatile) : ULLONG_MAX;
+}
+
+CXL_EXPORT unsigned long long
+cxl_cmd_partition_get_active_persistent_size(struct cxl_cmd *cmd)
+{
+	struct cxl_cmd_get_partition *c;
+
+	c = cmd_to_get_partition(cmd);
+	return c ? capacity_to_bytes(c->active_persistent) : ULLONG_MAX;
+}
+
+CXL_EXPORT unsigned long long
+cxl_cmd_partition_get_next_volatile_size(struct cxl_cmd *cmd)
+{
+	struct cxl_cmd_get_partition *c;
+
+	c = cmd_to_get_partition(cmd);
+	return c ? capacity_to_bytes(c->next_volatile) : ULLONG_MAX;
+}
+
+CXL_EXPORT unsigned long long
+cxl_cmd_partition_get_next_persistent_size(struct cxl_cmd *cmd)
+{
+	struct cxl_cmd_get_partition *c;
+
+	c = cmd_to_get_partition(cmd);
+	return c ? capacity_to_bytes(c->next_persistent) : ULLONG_MAX;
+}
+
 CXL_EXPORT int cxl_cmd_submit(struct cxl_cmd *cmd)
 {
 	struct cxl_memdev *memdev = cmd->memdev;
diff --git a/cxl/lib/libcxl.sym b/cxl/lib/libcxl.sym
index e56a2bf..509e62d 100644
--- a/cxl/lib/libcxl.sym
+++ b/cxl/lib/libcxl.sym
@@ -155,4 +155,9 @@  global:
 	cxl_dport_get_port;
 	cxl_port_get_dport_by_memdev;
 	cxl_dport_maps_memdev;
+	cxl_cmd_new_get_partition;
+	cxl_cmd_partition_get_active_volatile_size;
+	cxl_cmd_partition_get_active_persistent_size;
+	cxl_cmd_partition_get_next_volatile_size;
+	cxl_cmd_partition_get_next_persistent_size;
 } LIBCXL_1;
diff --git a/cxl/lib/private.h b/cxl/lib/private.h
index f483c30..7f3a562 100644
--- a/cxl/lib/private.h
+++ b/cxl/lib/private.h
@@ -7,6 +7,7 @@ 
 #include <cxl/cxl_mem.h>
 #include <ccan/endian/endian.h>
 #include <ccan/short_types/short_types.h>
+#include <util/size.h>
 
 #define CXL_EXPORT __attribute__ ((visibility("default")))
 
@@ -185,6 +186,15 @@  struct cxl_cmd_get_health_info {
 	le32 pmem_errors;
 } __attribute__((packed));
 
+struct cxl_cmd_get_partition {
+	le64 active_volatile;
+	le64 active_persistent;
+	le64 next_volatile;
+	le64 next_persistent;
+} __attribute__((packed));
+
+#define CXL_CAPACITY_MULTIPLIER		SZ_256M
+
 /* CXL 2.0 8.2.9.5.3 Byte 0 Health Status */
 #define CXL_CMD_HEALTH_INFO_STATUS_MAINTENANCE_NEEDED_MASK		BIT(0)
 #define CXL_CMD_HEALTH_INFO_STATUS_PERFORMANCE_DEGRADED_MASK		BIT(1)
diff --git a/cxl/libcxl.h b/cxl/libcxl.h
index 3b2293b..2c0a8d1 100644
--- a/cxl/libcxl.h
+++ b/cxl/libcxl.h
@@ -242,6 +242,11 @@  ssize_t cxl_cmd_read_label_get_payload(struct cxl_cmd *cmd, void *buf,
 		unsigned int length);
 struct cxl_cmd *cxl_cmd_new_write_label(struct cxl_memdev *memdev,
 		void *buf, unsigned int offset, unsigned int length);
+struct cxl_cmd *cxl_cmd_new_get_partition(struct cxl_memdev *memdev);
+unsigned long long cxl_cmd_partition_get_active_volatile_size(struct cxl_cmd *cmd);
+unsigned long long cxl_cmd_partition_get_active_persistent_size(struct cxl_cmd *cmd);
+unsigned long long cxl_cmd_partition_get_next_volatile_size(struct cxl_cmd *cmd);
+unsigned long long cxl_cmd_partition_get_next_persistent_size(struct cxl_cmd *cmd);
 
 #ifdef __cplusplus
 } /* extern "C" */
diff --git a/util/size.h b/util/size.h
index a0f3593..e72467f 100644
--- a/util/size.h
+++ b/util/size.h
@@ -15,6 +15,7 @@ 
 #define SZ_4M     0x00400000
 #define SZ_16M    0x01000000
 #define SZ_64M    0x04000000
+#define SZ_256M	  0x10000000
 #define SZ_1G     0x40000000
 #define SZ_1T 0x10000000000ULL