From c6603b1d6556cc02d0169f74508ab0e3e3e4bd76 Mon Sep 17 00:00:00 2001 From: Anuj Gupta Date: Mon, 30 Jun 2025 14:35:45 +0530 Subject: block: rename tuple_size field in blk_integrity to metadata_size The tuple_size field in blk_integrity currently represents the total size of metadata associated with each data interval. To make the meaning more explicit, rename tuple_size to metadata_size. This is a purely mechanical rename with no functional changes. Suggested-by: Martin K. Petersen Signed-off-by: Anuj Gupta Link: https://lore.kernel.org/20250630090548.3317-2-anuj20.g@samsung.com Reviewed-by: Christoph Hellwig Reviewed-by: Martin K. Petersen Signed-off-by: Christian Brauner --- include/linux/blk-integrity.h | 4 ++-- include/linux/blkdev.h | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-) (limited to 'include') diff --git a/include/linux/blk-integrity.h b/include/linux/blk-integrity.h index c7eae0bfb013..d27730da47f3 100644 --- a/include/linux/blk-integrity.h +++ b/include/linux/blk-integrity.h @@ -33,7 +33,7 @@ int blk_rq_integrity_map_user(struct request *rq, void __user *ubuf, static inline bool blk_integrity_queue_supports_integrity(struct request_queue *q) { - return q->limits.integrity.tuple_size; + return q->limits.integrity.metadata_size; } static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) @@ -74,7 +74,7 @@ static inline unsigned int bio_integrity_intervals(struct blk_integrity *bi, static inline unsigned int bio_integrity_bytes(struct blk_integrity *bi, unsigned int sectors) { - return bio_integrity_intervals(bi, sectors) * bi->tuple_size; + return bio_integrity_intervals(bi, sectors) * bi->metadata_size; } static inline bool blk_integrity_rq(struct request *rq) diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index a59880c809c7..ccda87d06a38 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -116,7 +116,7 @@ enum blk_integrity_checksum { struct blk_integrity { unsigned char flags; enum blk_integrity_checksum csum_type; - unsigned char tuple_size; + unsigned char metadata_size; unsigned char pi_offset; unsigned char interval_exp; unsigned char tag_size; -- cgit v1.2.3 From 76e45252a4cefa205439eb6610a244771e7d88da Mon Sep 17 00:00:00 2001 From: Anuj Gupta Date: Mon, 30 Jun 2025 14:35:46 +0530 Subject: block: introduce pi_tuple_size field in blk_integrity Introduce a new pi_tuple_size field in struct blk_integrity to explicitly represent the size (in bytes) of the protection information (PI) tuple. This is a prep patch. Add validation in blk_validate_integrity_limits() to ensure that pi size matches the expected size for known checksum types and never exceeds the pi_tuple_size. Suggested-by: Christoph Hellwig Signed-off-by: Anuj Gupta Link: https://lore.kernel.org/20250630090548.3317-3-anuj20.g@samsung.com Reviewed-by: Christoph Hellwig Reviewed-by: Martin K. Petersen Signed-off-by: Christian Brauner --- include/linux/blkdev.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index ccda87d06a38..0d4011dcfed3 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -120,6 +120,7 @@ struct blk_integrity { unsigned char pi_offset; unsigned char interval_exp; unsigned char tag_size; + unsigned char pi_tuple_size; }; typedef unsigned int __bitwise blk_mode_t; -- cgit v1.2.3 From 9eb22f7fedfc9eb1b7f431a5359abd4d15b0b0cd Mon Sep 17 00:00:00 2001 From: Anuj Gupta Date: Mon, 30 Jun 2025 14:35:48 +0530 Subject: fs: add ioctl to query metadata and protection info capabilities Add a new ioctl, FS_IOC_GETLBMD_CAP, 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: 1. lbmd_flags: bitmask of logical block metadata capability flags 2. lbmd_interval: the amount of data described by each unit of logical block metadata 3. lbmd_size: size in bytes of the logical block metadata associated with each interval 4. lbmd_opaque_size: size in bytes of the opaque block tag associated with each interval 5. lbmd_opaque_offset: offset in bytes of the opaque block tag within the logical block metadata 6. lbmd_pi_size: size in bytes of the T10 PI tuple associated with each interval 7. lbmd_pi_offset: offset in bytes of T10 PI tuple within the logical block metadata 8. lbmd_pi_guard_tag_type: T10 PI guard tag type 9. lbmd_pi_app_tag_size: size in bytes of the T10 PI application tag 10. lbmd_pi_ref_tag_size: size in bytes of the T10 PI reference tag 11. 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. Suggested-by: Martin K. Petersen Signed-off-by: Anuj Gupta Signed-off-by: Kanchan Joshi Link: https://lore.kernel.org/20250630090548.3317-5-anuj20.g@samsung.com Reviewed-by: Martin K. Petersen Reviewed-by: Christoph Hellwig Signed-off-by: Christian Brauner --- include/linux/blk-integrity.h | 7 +++++ include/uapi/linux/fs.h | 59 +++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 66 insertions(+) (limited to 'include') diff --git a/include/linux/blk-integrity.h b/include/linux/blk-integrity.h index d27730da47f3..e04c6e5bf1c6 100644 --- a/include/linux/blk-integrity.h +++ b/include/linux/blk-integrity.h @@ -29,6 +29,8 @@ int blk_rq_map_integrity_sg(struct request *, struct scatterlist *); int blk_rq_count_integrity_sg(struct request_queue *, struct bio *); int blk_rq_integrity_map_user(struct request *rq, void __user *ubuf, ssize_t bytes); +int blk_get_meta_cap(struct block_device *bdev, unsigned int cmd, + struct logical_block_metadata_cap __user *argp); static inline bool blk_integrity_queue_supports_integrity(struct request_queue *q) @@ -92,6 +94,11 @@ static inline struct bio_vec rq_integrity_vec(struct request *rq) rq->bio->bi_integrity->bip_iter); } #else /* CONFIG_BLK_DEV_INTEGRITY */ +static inline int blk_get_meta_cap(struct block_device *bdev, unsigned int cmd, + struct logical_block_metadata_cap __user *argp) +{ + return -EOPNOTSUPP; +} static inline int blk_rq_count_integrity_sg(struct request_queue *q, struct bio *b) { diff --git a/include/uapi/linux/fs.h b/include/uapi/linux/fs.h index 0098b0ce8ccb..83720a2fd20d 100644 --- a/include/uapi/linux/fs.h +++ b/include/uapi/linux/fs.h @@ -91,6 +91,63 @@ 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 @@ -247,6 +304,8 @@ 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) -- cgit v1.2.3