diff options
| -rw-r--r-- | block/block-backend.c | 6 | ||||
| -rw-r--r-- | block/file-posix.c | 2 | ||||
| -rw-r--r-- | block/io.c | 1 | ||||
| -rw-r--r-- | hw/scsi/scsi-generic.c | 2 | ||||
| -rw-r--r-- | include/block/block_int.h | 7 | ||||
| -rw-r--r-- | include/sysemu/block-backend.h | 1 |
6 files changed, 17 insertions, 2 deletions
diff --git a/block/block-backend.c b/block/block-backend.c index 6140d133e2..ba2b5ebb10 100644 --- a/block/block-backend.c +++ b/block/block-backend.c @@ -1986,6 +1986,12 @@ uint32_t blk_get_max_transfer(BlockBackend *blk) return ROUND_DOWN(max, blk_get_request_alignment(blk)); } +int blk_get_max_hw_iov(BlockBackend *blk) +{ + return MIN_NON_ZERO(blk->root->bs->bl.max_hw_iov, + blk->root->bs->bl.max_iov); +} + int blk_get_max_iov(BlockBackend *blk) { return blk->root->bs->bl.max_iov; diff --git a/block/file-posix.c b/block/file-posix.c index c62e42743d..53be0bdc1b 100644 --- a/block/file-posix.c +++ b/block/file-posix.c @@ -1273,7 +1273,7 @@ static void raw_refresh_limits(BlockDriverState *bs, Error **errp) ret = hdev_get_max_segments(s->fd, &st); if (ret > 0) { - bs->bl.max_iov = ret; + bs->bl.max_hw_iov = ret; } } } diff --git a/block/io.c b/block/io.c index 18d345a87a..bb0a254def 100644 --- a/block/io.c +++ b/block/io.c @@ -136,6 +136,7 @@ static void bdrv_merge_limits(BlockLimits *dst, const BlockLimits *src) dst->min_mem_alignment = MAX(dst->min_mem_alignment, src->min_mem_alignment); dst->max_iov = MIN_NON_ZERO(dst->max_iov, src->max_iov); + dst->max_hw_iov = MIN_NON_ZERO(dst->max_hw_iov, src->max_hw_iov); } typedef struct BdrvRefreshLimitsState { diff --git a/hw/scsi/scsi-generic.c b/hw/scsi/scsi-generic.c index 665baf900e..0306ccc7b1 100644 --- a/hw/scsi/scsi-generic.c +++ b/hw/scsi/scsi-generic.c @@ -180,7 +180,7 @@ static int scsi_handle_inquiry_reply(SCSIGenericReq *r, SCSIDevice *s, int len) page = r->req.cmd.buf[2]; if (page == 0xb0) { uint64_t max_transfer = blk_get_max_hw_transfer(s->conf.blk); - uint32_t max_iov = blk_get_max_iov(s->conf.blk); + uint32_t max_iov = blk_get_max_hw_iov(s->conf.blk); assert(max_transfer); max_transfer = MIN_NON_ZERO(max_transfer, max_iov * qemu_real_host_page_size) diff --git a/include/block/block_int.h b/include/block/block_int.h index ffe86068d4..f4c75e8ba9 100644 --- a/include/block/block_int.h +++ b/include/block/block_int.h @@ -718,6 +718,13 @@ typedef struct BlockLimits { */ uint64_t max_hw_transfer; + /* Maximal number of scatter/gather elements allowed by the hardware. + * Applies whenever transfers to the device bypass the kernel I/O + * scheduler, for example with SG_IO. If larger than max_iov + * or if zero, blk_get_max_hw_iov will fall back to max_iov. + */ + int max_hw_iov; + /* memory alignment, in bytes so that no bounce buffer is needed */ size_t min_mem_alignment; diff --git a/include/sysemu/block-backend.h b/include/sysemu/block-backend.h index 29d4fdbf63..82bae55161 100644 --- a/include/sysemu/block-backend.h +++ b/include/sysemu/block-backend.h @@ -211,6 +211,7 @@ uint32_t blk_get_request_alignment(BlockBackend *blk); uint32_t blk_get_max_transfer(BlockBackend *blk); uint64_t blk_get_max_hw_transfer(BlockBackend *blk); int blk_get_max_iov(BlockBackend *blk); +int blk_get_max_hw_iov(BlockBackend *blk); void blk_set_guest_block_size(BlockBackend *blk, int align); void *blk_try_blockalign(BlockBackend *blk, size_t size); void *blk_blockalign(BlockBackend *blk, size_t size); |