diff options
author | Paolo Bonzini <pbonzini@redhat.com> | 2021-04-14 19:51:48 +0200 |
---|---|---|
committer | Paolo Bonzini <pbonzini@redhat.com> | 2021-06-25 10:54:12 +0200 |
commit | 01ef8185b809af9d287e1a03a3f9d8ea8231118a (patch) | |
tree | 3310b456ff028325cfe6b5e7bb286ab1c57ecc68 /block/file-posix.c | |
parent | 8ad5ab6148dca8aad297c134c09c84b0b92d45ed (diff) |
scsi-generic: pass max_segments via max_iov field in BlockLimits
I/O to a disk via read/write is not limited by the number of segments allowed
by the host adapter; the kernel can split requests if needed, and the limit
imposed by the host adapter can be very low (256k or so) to avoid that SG_IO
returns EINVAL if memory is heavily fragmented.
Since this value is only interesting for SG_IO-based I/O, do not include
it in the max_transfer and only take it into account when patching the
block limits VPD page in the scsi-generic device.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Diffstat (limited to 'block/file-posix.c')
-rw-r--r-- | block/file-posix.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/block/file-posix.c b/block/file-posix.c index b8dc19ce1a..6db690baf2 100644 --- a/block/file-posix.c +++ b/block/file-posix.c @@ -1237,8 +1237,7 @@ static void raw_refresh_limits(BlockDriverState *bs, Error **errp) ret = sg_get_max_segments(s->fd); if (ret > 0) { - bs->bl.max_transfer = MIN(bs->bl.max_transfer, - ret * qemu_real_host_page_size); + bs->bl.max_iov = ret; } } |