| commit | 01ef8185b809af9d287e1a03a3f9d8ea8231118a | |
| author | Paolo Bonzini <pbonzini@redhat.com> | |
| Wed, 14 Apr 2021 17:51:48 +0000 (14 19:51 +0200) | ||
| committer | Paolo Bonzini <pbonzini@redhat.com> | |
| Fri, 25 Jun 2021 08:54:12 +0000 (25 10:54 +0200) | ||
| tree | 3310b456ff028325cfe6b5e7bb286ab1c57ecc68 | treesnapshot (tar.gz zip) |
| parent | 8ad5ab6148dca8aad297c134c09c84b0b92d45ed | commitdiff |
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>
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>
| block/file-posix.c | diffblobblamehistory | |
| hw/scsi/scsi-generic.c | diffblobblamehistory |