diff options
| author | Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> | 2011-10-12 12:12:36 -0400 |
|---|---|---|
| committer | Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> | 2011-11-18 13:27:59 -0500 |
| commit | 97e36834f5a106459ab1b290e663a4eb6264639e (patch) | |
| tree | 39e4843998cb7f75b94d80f27e4b11ffb3662f28 /include/xen | |
| parent | cfcfc9eca2bcbd26a8e206baeb005b055dbf8e37 (diff) | |
| download | linux-97e36834f5a106459ab1b290e663a4eb6264639e.tar.bz2 | |
xen/blk[front|back]: Squash blkif_request_rw and blkif_request_discard together
In a union type structure to deal with the overlapping
attributes in a easier manner.
Suggested-by: Ian Campbell <Ian.Campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Diffstat (limited to 'include/xen')
| -rw-r--r-- | include/xen/interface/io/blkif.h | 24 |
1 files changed, 17 insertions, 7 deletions
diff --git a/include/xen/interface/io/blkif.h b/include/xen/interface/io/blkif.h index 9324488f23f0..f88e28b6a27c 100644 --- a/include/xen/interface/io/blkif.h +++ b/include/xen/interface/io/blkif.h @@ -95,6 +95,12 @@ typedef uint64_t blkif_sector_t; #define BLKIF_MAX_SEGMENTS_PER_REQUEST 11 struct blkif_request_rw { + uint8_t nr_segments; /* number of segments */ + blkif_vdev_t handle; /* only for read/write requests */ +#ifdef CONFIG_X86_64 + uint32_t _pad1; /* offsetof(blkif_request,u.rw.id) == 8 */ +#endif + uint64_t id; /* private guest value, echoed in resp */ blkif_sector_t sector_number;/* start sector idx on disk (r/w only) */ struct blkif_request_segment { grant_ref_t gref; /* reference to I/O buffer frame */ @@ -102,23 +108,27 @@ struct blkif_request_rw { /* @last_sect: last sector in frame to transfer (inclusive). */ uint8_t first_sect, last_sect; } seg[BLKIF_MAX_SEGMENTS_PER_REQUEST]; -}; +} __attribute__((__packed__)); struct blkif_request_discard { + uint8_t nr_segments; /* number of segments */ + blkif_vdev_t _pad1; /* only for read/write requests */ +#ifdef CONFIG_X86_64 + uint32_t _pad2; /* offsetof(blkif_req..,u.discard.id)==8*/ +#endif + uint64_t id; /* private guest value, echoed in resp */ blkif_sector_t sector_number; - uint64_t nr_sectors; -}; + uint64_t nr_sectors; + uint8_t _pad3; +} __attribute__((__packed__)); struct blkif_request { uint8_t operation; /* BLKIF_OP_??? */ - uint8_t nr_segments; /* number of segments */ - blkif_vdev_t handle; /* only for read/write requests */ - uint64_t id; /* private guest value, echoed in resp */ union { struct blkif_request_rw rw; struct blkif_request_discard discard; } u; -}; +} __attribute__((__packed__)); struct blkif_response { uint64_t id; /* copied from request */ |