Merge tag 'vfs-6.17-rc1.integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull vfs 'protection info' updates from Christian Brauner:
 "This adds the new FS_IOC_GETLBMD_CAP ioctl() to query metadata and
  protection info (PI) capabilities. This ioctl returns information
  about the files integrity profile. This is useful for userspace
  applications to understand a files end-to-end data protection support
  and configure the I/O accordingly.

  For now this interface is only supported by block devices. However the
  design and placement of this ioctl in generic FS ioctl space allows us
  to extend it to work over files as well. This maybe useful when
  filesystems start supporting PI-aware layouts.

  A new structure struct logical_block_metadata_cap is introduced, which
  contains the following fields:

   - lbmd_flags:
     bitmask of logical block metadata capability flags

   - lbmd_interval:
     the amount of data described by each unit of logical block metadata

   - lbmd_size:
     size in bytes of the logical block metadata associated with each
     interval

   - lbmd_opaque_size:
     size in bytes of the opaque block tag associated with each interval

   - lbmd_opaque_offset:
     offset in bytes of the opaque block tag within the logical block
     metadata

   - lbmd_pi_size:
     size in bytes of the T10 PI tuple associated with each interval

   - lbmd_pi_offset:
     offset in bytes of T10 PI tuple within the logical block metadata

   - lbmd_pi_guard_tag_type:
     T10 PI guard tag type

   - lbmd_pi_app_tag_size:
     size in bytes of the T10 PI application tag

   - lbmd_pi_ref_tag_size:
     size in bytes of the T10 PI reference tag

   - lbmd_pi_storage_tag_size:
     size in bytes of the T10 PI storage tag

  The internal logic to fetch the capability is encapsulated in a helper
  function blk_get_meta_cap(), which uses the blk_integrity profile
  associated with the device. The ioctl returns -EOPNOTSUPP, if
  CONFIG_BLK_DEV_INTEGRITY is not enabled"

* tag 'vfs-6.17-rc1.integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  block: fix lbmd_guard_tag_type assignment in FS_IOC_GETLBMD_CAP
  block: fix FS_IOC_GETLBMD_CAP parsing in blkdev_common_ioctl()
  fs: add ioctl to query metadata and protection info capabilities
  nvme: set pi_offset only when checksum type is not BLK_INTEGRITY_CSUM_NONE
  block: introduce pi_tuple_size field in blk_integrity
  block: rename tuple_size field in blk_integrity to metadata_size

1 files changed, 59 insertions, 0 deletions

diff --git a/include/uapi/linux/fs.h b/include/uapi/linux/fs.h
index 28238a3edbc1..955a39b0590f 100644
--- a/include/uapi/linux/fs.h
+++ b/include/uapi/linux/fs.h
@@ -102,6 +102,63 @@ struct fs_sysfs_path {
 	__u8			name[128];
 };
 
+/* Protection info capability flags */
+#define	LBMD_PI_CAP_INTEGRITY		(1 << 0)
+#define	LBMD_PI_CAP_REFTAG		(1 << 1)
+
+/* Checksum types for Protection Information */
+#define LBMD_PI_CSUM_NONE		0
+#define LBMD_PI_CSUM_IP			1
+#define LBMD_PI_CSUM_CRC16_T10DIF	2
+#define LBMD_PI_CSUM_CRC64_NVME		4
+
+/* sizeof first published struct */
+#define LBMD_SIZE_VER0			16
+
+/*
+ * Logical block metadata capability descriptor
+ * If the device does not support metadata, all the fields will be zero.
+ * Applications must check lbmd_flags to determine whether metadata is
+ * supported or not.
+ */
+struct logical_block_metadata_cap {
+	/* Bitmask of logical block metadata capability flags */
+	__u32	lbmd_flags;
+	/*
+	 * The amount of data described by each unit of logical block
+	 * metadata
+	 */
+	__u16	lbmd_interval;
+	/*
+	 * Size in bytes of the logical block metadata associated with each
+	 * interval
+	 */
+	__u8	lbmd_size;
+	/*
+	 * Size in bytes of the opaque block tag associated with each
+	 * interval
+	 */
+	__u8	lbmd_opaque_size;
+	/*
+	 * Offset in bytes of the opaque block tag within the logical block
+	 * metadata
+	 */
+	__u8	lbmd_opaque_offset;
+	/* Size in bytes of the T10 PI tuple associated with each interval */
+	__u8	lbmd_pi_size;
+	/* Offset in bytes of T10 PI tuple within the logical block metadata */
+	__u8	lbmd_pi_offset;
+	/* T10 PI guard tag type */
+	__u8	lbmd_guard_tag_type;
+	/* Size in bytes of the T10 PI application tag */
+	__u8	lbmd_app_tag_size;
+	/* Size in bytes of the T10 PI reference tag */
+	__u8	lbmd_ref_tag_size;
+	/* Size in bytes of the T10 PI storage tag */
+	__u8	lbmd_storage_tag_size;
+	__u8	pad;
+};
+
 /* extent-same (dedupe) ioctls; these MUST match the btrfs ioctl definitions */
 #define FILE_DEDUPE_RANGE_SAME		0
 #define FILE_DEDUPE_RANGE_DIFFERS	1
@@ -258,6 +315,8 @@ struct fsxattr {
  * also /sys/kernel/debug/ for filesystems with debugfs exports
  */
 #define FS_IOC_GETFSSYSFSPATH		_IOR(0x15, 1, struct fs_sysfs_path)
+/* Get logical block metadata capability details */
+#define FS_IOC_GETLBMD_CAP		_IOWR(0x15, 2, struct logical_block_metadata_cap)
 
 /*
  * Inode flags (FS_IOC_GETFLAGS / FS_IOC_SETFLAGS)