diff options
Diffstat (limited to 'include/xen/interface/io/blkif.h')
| -rw-r--r-- | include/xen/interface/io/blkif.h | 44 |
1 files changed, 19 insertions, 25 deletions
diff --git a/include/xen/interface/io/blkif.h b/include/xen/interface/io/blkif.h index 65e12099ef8..32ec05a6572 100644 --- a/include/xen/interface/io/blkif.h +++ b/include/xen/interface/io/blkif.h @@ -113,13 +113,13 @@ typedef uint64_t blkif_sector_t; * it's less than the number provided by the backend. The indirect_grefs field * in blkif_request_indirect should be filled by the frontend with the * grant references of the pages that are holding the indirect segments. - * This pages are filled with an array of blkif_request_segment_aligned - * that hold the information about the segments. The number of indirect - * pages to use is determined by the maximum number of segments - * a indirect request contains. Every indirect page can contain a maximum - * of 512 segments (PAGE_SIZE/sizeof(blkif_request_segment_aligned)), - * so to calculate the number of indirect pages to use we have to do - * ceil(indirect_segments/512). + * These pages are filled with an array of blkif_request_segment that hold the + * information about the segments. The number of indirect pages to use is + * determined by the number of segments an indirect request contains. Every + * indirect page can contain a maximum of + * (PAGE_SIZE / sizeof(struct blkif_request_segment)) segments, so to + * calculate the number of indirect pages to use we have to do + * ceil(indirect_segments / (PAGE_SIZE / sizeof(struct blkif_request_segment))). * * If a backend does not recognize BLKIF_OP_INDIRECT, it should *not* * create the "feature-max-indirect-segments" node! @@ -135,35 +135,29 @@ typedef uint64_t blkif_sector_t; #define BLKIF_MAX_INDIRECT_PAGES_PER_REQUEST 8 -struct blkif_request_segment_aligned { - grant_ref_t gref; /* reference to I/O buffer frame */ - /* @first_sect: first sector in frame to transfer (inclusive). */ - /* @last_sect: last sector in frame to transfer (inclusive). */ - uint8_t first_sect, last_sect; - uint16_t _pad; /* padding to make it 8 bytes, so it's cache-aligned */ -} __attribute__((__packed__)); +struct blkif_request_segment { + grant_ref_t gref; /* reference to I/O buffer frame */ + /* @first_sect: first sector in frame to transfer (inclusive). */ + /* @last_sect: last sector in frame to transfer (inclusive). */ + uint8_t first_sect, last_sect; +}; struct blkif_request_rw { uint8_t nr_segments; /* number of segments */ blkif_vdev_t handle; /* only for read/write requests */ -#ifdef CONFIG_X86_64 +#ifndef CONFIG_X86_32 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 */ - /* @first_sect: first sector in frame to transfer (inclusive). */ - /* @last_sect: last sector in frame to transfer (inclusive). */ - uint8_t first_sect, last_sect; - } seg[BLKIF_MAX_SEGMENTS_PER_REQUEST]; + struct blkif_request_segment seg[BLKIF_MAX_SEGMENTS_PER_REQUEST]; } __attribute__((__packed__)); struct blkif_request_discard { uint8_t flag; /* BLKIF_DISCARD_SECURE or zero. */ #define BLKIF_DISCARD_SECURE (1<<0) /* ignored if discard-secure=0 */ blkif_vdev_t _pad1; /* only for read/write requests */ -#ifdef CONFIG_X86_64 +#ifndef CONFIG_X86_32 uint32_t _pad2; /* offsetof(blkif_req..,u.discard.id)==8*/ #endif uint64_t id; /* private guest value, echoed in resp */ @@ -175,7 +169,7 @@ struct blkif_request_discard { struct blkif_request_other { uint8_t _pad1; blkif_vdev_t _pad2; /* only for read/write requests */ -#ifdef CONFIG_X86_64 +#ifndef CONFIG_X86_32 uint32_t _pad3; /* offsetof(blkif_req..,u.other.id)==8*/ #endif uint64_t id; /* private guest value, echoed in resp */ @@ -184,7 +178,7 @@ struct blkif_request_other { struct blkif_request_indirect { uint8_t indirect_op; uint16_t nr_segments; -#ifdef CONFIG_X86_64 +#ifndef CONFIG_X86_32 uint32_t _pad1; /* offsetof(blkif_...,u.indirect.id) == 8 */ #endif uint64_t id; @@ -192,7 +186,7 @@ struct blkif_request_indirect { blkif_vdev_t handle; uint16_t _pad2; grant_ref_t indirect_grefs[BLKIF_MAX_INDIRECT_PAGES_PER_REQUEST]; -#ifdef CONFIG_X86_64 +#ifndef CONFIG_X86_32 uint32_t _pad3; /* make it 64 byte aligned */ #else uint64_t _pad3; /* make it 64 byte aligned */ |