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 <hch@lst.de>
Signed-off-by: Anuj Gupta <anuj20.g@samsung.com>
Link: https://lore.kernel.org/20250630090548.3317-3-anuj20.g@samsung.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>

diff --git a/block/blk-settings.c b/block/blk-settings.c
index 787500ff00c3cdd88fd053102440c735dd76c8f9..32f3cdc9835ad05cfa90f30c83524203ba733041 100644 (file)
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -14,6 +14,8 @@
 #include <linux/jiffies.h>
 #include <linux/gfp.h>
 #include <linux/dma-mapping.h>
+#include <linux/t10-pi.h>
+#include <linux/crc64.h>
 
 #include "blk.h"
 #include "blk-rq-qos.h"
@@ -135,6 +137,42 @@ static int blk_validate_integrity_limits(struct queue_limits *lim)
                return -EINVAL;
        }
 
+       if (bi->pi_tuple_size > bi->metadata_size) {
+               pr_warn("pi_tuple_size (%u) exceeds metadata_size (%u)\n",
+                        bi->pi_tuple_size,
+                        bi->metadata_size);
+               return -EINVAL;
+       }
+
+       switch (bi->csum_type) {
+       case BLK_INTEGRITY_CSUM_NONE:
+               if (bi->pi_tuple_size) {
+                       pr_warn("pi_tuple_size must be 0 when checksum type \
+                                is none\n");
+                       return -EINVAL;
+               }
+               break;
+       case BLK_INTEGRITY_CSUM_CRC:
+       case BLK_INTEGRITY_CSUM_IP:
+               if (bi->pi_tuple_size != sizeof(struct t10_pi_tuple)) {
+                       pr_warn("pi_tuple_size mismatch for T10 PI: expected \
+                                %zu, got %u\n",
+                                sizeof(struct t10_pi_tuple),
+                                bi->pi_tuple_size);
+                       return -EINVAL;
+               }
+               break;
+       case BLK_INTEGRITY_CSUM_CRC64:
+               if (bi->pi_tuple_size != sizeof(struct crc64_pi_tuple)) {
+                       pr_warn("pi_tuple_size mismatch for CRC64 PI: \
+                                expected %zu, got %u\n",
+                                sizeof(struct crc64_pi_tuple),
+                                bi->pi_tuple_size);
+                       return -EINVAL;
+               }
+               break;
+       }
+
        if (!bi->interval_exp)
                bi->interval_exp = ilog2(lim->logical_block_size);
 

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index b027dda38e69230f9e19c7d6b511004d91aa2995..fe72accab5160079e3b5a0b2c7368e1437b2a149 100644 (file)
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -1867,6 +1867,8 @@ static bool nvme_init_integrity(struct nvme_ns_head *head,
        }
 
        bi->metadata_size = head->ms;
+       if (bi->csum_type)
+               bi->pi_tuple_size = head->pi_size;
        bi->pi_offset = info->pi_offset;
        return true;
 }

diff --git a/drivers/scsi/sd_dif.c b/drivers/scsi/sd_dif.c
index 18bfca1f1c783a2dc68c03eef164638fc91d9319..ff4217fef93b4b2c24385d5faa90ba9e6628b373 100644 (file)
--- a/drivers/scsi/sd_dif.c
+++ b/drivers/scsi/sd_dif.c
@@ -53,6 +53,7 @@ void sd_dif_config_host(struct scsi_disk *sdkp, struct queue_limits *lim)
                bi->flags |= BLK_INTEGRITY_REF_TAG;
 
        bi->metadata_size = sizeof(struct t10_pi_tuple);
+       bi->pi_tuple_size = bi->metadata_size;
 
        if (dif && type) {
                bi->flags |= BLK_INTEGRITY_DEVICE_CAPABLE;

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index ccda87d06a38d5d6c9bcdad532fd6eaa27ead14f..0d4011dcfed321b5569b86dfc91023c4302b225a 100644 (file)
--- 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;