[Date Prev] | [Thread Prev] | [Thread Next] | [Date Next] -- [Date Index] | [Thread Index] | [List Home]
Subject: Re: [virtio] [OASIS Issue Tracker] Created: (VIRTIO-20) block: remove ioprio field
OASIS Issues Tracker <workgroup_mailer@lists.oasis-open.org> writes: > block: remove ioprio field > -------------------------- > > Key: VIRTIO-20 > URL: http://tools.oasis-open.org/issues/browse/VIRTIO-20 > Project: OASIS Virtual I/O Device (VIRTIO) TC > Issue Type: Improvement > Reporter: Rusty Russell > > > Did anyone ever actually use it? We could add it again with a feature when someone does... commit 7bc092262d787a20e6b09d1cb3a659cf1f37a1d2 Author: Rusty Russell <rusty@au1.ibm.com> Date: Wed Sep 11 13:33:46 2013 +0930 2.4.2.5: Remove ioprio field. Leave a reserved field in there for alignment. See: https://tools.oasis-open.org/issues/browse/VIRTIO-20 Signed-off-by: Rusty Russell <rusty@au1.ibm.com> diff --git a/virtio-v1.0-wd01-part1-specification.txt b/virtio-v1.0-wd01-part1-specification.txt index 6ab1feb..f82b5f6 100644 --- a/virtio-v1.0-wd01-part1-specification.txt +++ b/virtio-v1.0-wd01-part1-specification.txt @@ -1659,7 +1659,7 @@ the device (not necessarily in order). Each request is of form: struct virtio_blk_req { u32 type; - u32 ioprio; + u32 reserved; u64 sector; char data[][512]; u8 status; @@ -1682,10 +1682,6 @@ flush the host cache. #define VIRTIO_BLK_T_FLUSH_OUT 5 #define VIRTIO_BLK_T_BARRIER 0x80000000 -The ioprio field is a hint about the relative priorities of -requests to the device: higher numbers indicate more important -requests. - The sector number indicates the offset (multiplied by 512) where the read or write is to occur. This field is unused and set to 0 for scsi packet commands and for flush commands. @@ -1700,6 +1696,10 @@ error or VIRTIO_BLK_S_UNSUPP for a request unsupported by host: 2.4.2.5.1 Legacy Interface: Device Operation ------------------------ +The 'reserved' field was previously called ioprio. The ioprio field +is a hint about the relative priorities of requests to the device: +higher numbers indicate more important requests. + Historically, devices assumed that the fields type, ioprio and sector reside in a single, separate read-only buffer and the status field is a separate read-only buffer of size 1 byte, by itself.
[Date Prev] | [Thread Prev] | [Thread Next] | [Date Next] -- [Date Index] | [Thread Index] | [List Home]