diff options
Diffstat (limited to 'kernel/drivers/block/xen-blkback/common.h')
| -rw-r--r-- | kernel/drivers/block/xen-blkback/common.h | 31 |
1 files changed, 21 insertions, 10 deletions
diff --git a/kernel/drivers/block/xen-blkback/common.h b/kernel/drivers/block/xen-blkback/common.h index f620b5d3f..c929ae227 100644 --- a/kernel/drivers/block/xen-blkback/common.h +++ b/kernel/drivers/block/xen-blkback/common.h @@ -39,23 +39,33 @@ #include <asm/pgalloc.h> #include <asm/hypervisor.h> #include <xen/grant_table.h> +#include <xen/page.h> #include <xen/xenbus.h> #include <xen/interface/io/ring.h> #include <xen/interface/io/blkif.h> #include <xen/interface/io/protocols.h> +extern unsigned int xen_blkif_max_ring_order; /* * This is the maximum number of segments that would be allowed in indirect * requests. This value will also be passed to the frontend. */ #define MAX_INDIRECT_SEGMENTS 256 -#define SEGS_PER_INDIRECT_FRAME \ - (PAGE_SIZE/sizeof(struct blkif_request_segment)) +/* + * Xen use 4K pages. The guest may use different page size (4K or 64K) + * Number of Xen pages per segment + */ +#define XEN_PAGES_PER_SEGMENT (PAGE_SIZE / XEN_PAGE_SIZE) + +#define XEN_PAGES_PER_INDIRECT_FRAME \ + (XEN_PAGE_SIZE/sizeof(struct blkif_request_segment)) +#define SEGS_PER_INDIRECT_FRAME \ + (XEN_PAGES_PER_INDIRECT_FRAME / XEN_PAGES_PER_SEGMENT) + #define MAX_INDIRECT_PAGES \ ((MAX_INDIRECT_SEGMENTS + SEGS_PER_INDIRECT_FRAME - 1)/SEGS_PER_INDIRECT_FRAME) -#define INDIRECT_PAGES(_segs) \ - ((_segs + SEGS_PER_INDIRECT_FRAME - 1)/SEGS_PER_INDIRECT_FRAME) +#define INDIRECT_PAGES(_segs) DIV_ROUND_UP(_segs, XEN_PAGES_PER_INDIRECT_FRAME) /* Not a real protocol. Used to generate ring structs which contain * the elements common to all protocols only. This way we get a @@ -248,7 +258,7 @@ struct backend_info; #define PERSISTENT_GNT_WAS_ACTIVE 1 /* Number of requests that we can fit in a ring */ -#define XEN_BLKIF_REQS 32 +#define XEN_BLKIF_REQS_PER_PAGE 32 struct persistent_gnt { struct page *page; @@ -320,6 +330,7 @@ struct xen_blkif { struct work_struct free_work; /* Thread shutdown wait queue. */ wait_queue_head_t shutdown_wq; + unsigned int nr_ring_pages; }; struct seg_buf { @@ -343,7 +354,7 @@ struct grant_page { struct pending_req { struct xen_blkif *blkif; u64 id; - int nr_pages; + int nr_segs; atomic_t pendcnt; unsigned short operation; int status; @@ -397,8 +408,8 @@ static inline void blkif_get_x86_32_req(struct blkif_request *dst, struct blkif_x86_32_request *src) { int i, n = BLKIF_MAX_SEGMENTS_PER_REQUEST, j; - dst->operation = src->operation; - switch (src->operation) { + dst->operation = READ_ONCE(src->operation); + switch (dst->operation) { case BLKIF_OP_READ: case BLKIF_OP_WRITE: case BLKIF_OP_WRITE_BARRIER: @@ -445,8 +456,8 @@ static inline void blkif_get_x86_64_req(struct blkif_request *dst, struct blkif_x86_64_request *src) { int i, n = BLKIF_MAX_SEGMENTS_PER_REQUEST, j; - dst->operation = src->operation; - switch (src->operation) { + dst->operation = READ_ONCE(src->operation); + switch (dst->operation) { case BLKIF_OP_READ: case BLKIF_OP_WRITE: case BLKIF_OP_WRITE_BARRIER: |