scsi: sd_zbc: block: Respect bio vector limits for REPORT ZONES buffer

The REPORT ZONES buffer size is currently limited by the HBA's maximum
segment count to ensure the buffer can be mapped. However, the block
layer further limits the number of iovec entries to 1024 when allocating
a bio.

To avoid allocation of buffers too large to be mapped, further restrict
the maximum buffer size to BIO_MAX_INLINE_VECS.

Replace the UIO_MAXIOV symbolic name with the more contextually
appropriate BIO_MAX_INLINE_VECS.

Fixes: b091ac6168 ("sd_zbc: Fix report zones buffer allocation")
Cc: stable@vger.kernel.org
Signed-off-by: Steve Siwinski <ssiwinski@atto.com>
Link: https://lore.kernel.org/r/20250508200122.243129-1-ssiwinski@atto.com
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Steve Siwinski 2025-05-08 16:01:22 -04:00 committed by Martin K. Petersen
parent 0e9693b97a
commit e8007fad54
3 changed files with 7 additions and 2 deletions

View file

@ -611,7 +611,7 @@ struct bio *bio_kmalloc(unsigned short nr_vecs, gfp_t gfp_mask)
{
struct bio *bio;
if (nr_vecs > UIO_MAXIOV)
if (nr_vecs > BIO_MAX_INLINE_VECS)
return NULL;
return kmalloc(struct_size(bio, bi_inline_vecs, nr_vecs), gfp_mask);
}

View file

@ -169,6 +169,7 @@ static void *sd_zbc_alloc_report_buffer(struct scsi_disk *sdkp,
unsigned int nr_zones, size_t *buflen)
{
struct request_queue *q = sdkp->disk->queue;
unsigned int max_segments;
size_t bufsize;
void *buf;
@ -180,12 +181,15 @@ static void *sd_zbc_alloc_report_buffer(struct scsi_disk *sdkp,
* Furthermore, since the report zone command cannot be split, make
* sure that the allocated buffer can always be mapped by limiting the
* number of pages allocated to the HBA max segments limit.
* Since max segments can be larger than the max inline bio vectors,
* further limit the allocated buffer to BIO_MAX_INLINE_VECS.
*/
nr_zones = min(nr_zones, sdkp->zone_info.nr_zones);
bufsize = roundup((nr_zones + 1) * 64, SECTOR_SIZE);
bufsize = min_t(size_t, bufsize,
queue_max_hw_sectors(q) << SECTOR_SHIFT);
bufsize = min_t(size_t, bufsize, queue_max_segments(q) << PAGE_SHIFT);
max_segments = min(BIO_MAX_INLINE_VECS, queue_max_segments(q));
bufsize = min_t(size_t, bufsize, max_segments << PAGE_SHIFT);
while (bufsize >= SECTOR_SIZE) {
buf = kvzalloc(bufsize, GFP_KERNEL | __GFP_NORETRY);

View file

@ -11,6 +11,7 @@
#include <linux/uio.h>
#define BIO_MAX_VECS 256U
#define BIO_MAX_INLINE_VECS UIO_MAXIOV
struct queue_limits;