diff options
Diffstat (limited to 'drivers/block/xen-blkback/blkback.c')
| -rw-r--r-- | drivers/block/xen-blkback/blkback.c | 126 |
1 files changed, 115 insertions, 11 deletions
diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c index a5cf7f1e871c..c362f4ad80ab 100644 --- a/drivers/block/xen-blkback/blkback.c +++ b/drivers/block/xen-blkback/blkback.c @@ -239,9 +239,9 @@ static void put_persistent_gnt(struct xen_blkif_ring *ring, atomic_dec(&ring->persistent_gnt_in_use); } -static void free_persistent_gnts(struct xen_blkif_ring *ring, struct rb_root *root, - unsigned int num) +static void free_persistent_gnts(struct xen_blkif_ring *ring) { + struct rb_root *root = &ring->persistent_gnts; struct gnttab_unmap_grant_ref unmap[BLKIF_MAX_SEGMENTS_PER_REQUEST]; struct page *pages[BLKIF_MAX_SEGMENTS_PER_REQUEST]; struct persistent_gnt *persistent_gnt; @@ -249,6 +249,9 @@ static void free_persistent_gnts(struct xen_blkif_ring *ring, struct rb_root *ro int segs_to_unmap = 0; struct gntab_unmap_queue_data unmap_data; + if (RB_EMPTY_ROOT(root)) + return; + unmap_data.pages = pages; unmap_data.unmap_ops = unmap; unmap_data.kunmap_ops = NULL; @@ -277,9 +280,11 @@ static void free_persistent_gnts(struct xen_blkif_ring *ring, struct rb_root *ro rb_erase(&persistent_gnt->node, root); kfree(persistent_gnt); - num--; + ring->persistent_gnt_c--; } - BUG_ON(num != 0); + + BUG_ON(!RB_EMPTY_ROOT(&ring->persistent_gnts)); + BUG_ON(ring->persistent_gnt_c != 0); } void xen_blkbk_unmap_purged_grants(struct work_struct *work) @@ -631,12 +636,7 @@ purge_gnt_list: void xen_blkbk_free_caches(struct xen_blkif_ring *ring) { /* Free all persistent grant pages */ - if (!RB_EMPTY_ROOT(&ring->persistent_gnts)) - free_persistent_gnts(ring, &ring->persistent_gnts, - ring->persistent_gnt_c); - - BUG_ON(!RB_EMPTY_ROOT(&ring->persistent_gnts)); - ring->persistent_gnt_c = 0; + free_persistent_gnts(ring); /* Since we are shutting down remove all pages from the buffer */ gnttab_page_cache_shrink(&ring->free_pages, 0 /* All */); @@ -891,7 +891,7 @@ next: out: for (i = last_map; i < num; i++) { /* Don't zap current batch's valid persistent grants. */ - if(i >= map_until) + if (i >= map_until) pages[i]->persistent_gnt = NULL; pages[i]->handle = BLKBACK_INVALID_HANDLE; } @@ -1072,7 +1072,111 @@ static void end_block_io_op(struct bio *bio) bio_put(bio); } +static void blkif_get_x86_32_req(struct blkif_request *dst, + const struct blkif_x86_32_request *src) +{ + unsigned int i, n; + + dst->operation = READ_ONCE(src->operation); + + switch (dst->operation) { + case BLKIF_OP_READ: + case BLKIF_OP_WRITE: + case BLKIF_OP_WRITE_BARRIER: + case BLKIF_OP_FLUSH_DISKCACHE: + dst->u.rw.nr_segments = READ_ONCE(src->u.rw.nr_segments); + dst->u.rw.handle = src->u.rw.handle; + dst->u.rw.id = src->u.rw.id; + dst->u.rw.sector_number = src->u.rw.sector_number; + n = min_t(unsigned int, BLKIF_MAX_SEGMENTS_PER_REQUEST, + dst->u.rw.nr_segments); + for (i = 0; i < n; i++) + dst->u.rw.seg[i] = src->u.rw.seg[i]; + break; + + case BLKIF_OP_DISCARD: + dst->u.discard.flag = src->u.discard.flag; + dst->u.discard.id = src->u.discard.id; + dst->u.discard.sector_number = src->u.discard.sector_number; + dst->u.discard.nr_sectors = src->u.discard.nr_sectors; + break; + + case BLKIF_OP_INDIRECT: + dst->u.indirect.indirect_op = src->u.indirect.indirect_op; + dst->u.indirect.nr_segments = + READ_ONCE(src->u.indirect.nr_segments); + dst->u.indirect.handle = src->u.indirect.handle; + dst->u.indirect.id = src->u.indirect.id; + dst->u.indirect.sector_number = src->u.indirect.sector_number; + n = min(MAX_INDIRECT_PAGES, + INDIRECT_PAGES(dst->u.indirect.nr_segments)); + for (i = 0; i < n; i++) + dst->u.indirect.indirect_grefs[i] = + src->u.indirect.indirect_grefs[i]; + break; + + default: + /* + * Don't know how to translate this op. Only get the + * ID so failure can be reported to the frontend. + */ + dst->u.other.id = src->u.other.id; + break; + } +} + +static void blkif_get_x86_64_req(struct blkif_request *dst, + const struct blkif_x86_64_request *src) +{ + unsigned int i, n; + + dst->operation = READ_ONCE(src->operation); + + switch (dst->operation) { + case BLKIF_OP_READ: + case BLKIF_OP_WRITE: + case BLKIF_OP_WRITE_BARRIER: + case BLKIF_OP_FLUSH_DISKCACHE: + dst->u.rw.nr_segments = READ_ONCE(src->u.rw.nr_segments); + dst->u.rw.handle = src->u.rw.handle; + dst->u.rw.id = src->u.rw.id; + dst->u.rw.sector_number = src->u.rw.sector_number; + n = min_t(unsigned int, BLKIF_MAX_SEGMENTS_PER_REQUEST, + dst->u.rw.nr_segments); + for (i = 0; i < n; i++) + dst->u.rw.seg[i] = src->u.rw.seg[i]; + break; + + case BLKIF_OP_DISCARD: + dst->u.discard.flag = src->u.discard.flag; + dst->u.discard.id = src->u.discard.id; + dst->u.discard.sector_number = src->u.discard.sector_number; + dst->u.discard.nr_sectors = src->u.discard.nr_sectors; + break; + + case BLKIF_OP_INDIRECT: + dst->u.indirect.indirect_op = src->u.indirect.indirect_op; + dst->u.indirect.nr_segments = + READ_ONCE(src->u.indirect.nr_segments); + dst->u.indirect.handle = src->u.indirect.handle; + dst->u.indirect.id = src->u.indirect.id; + dst->u.indirect.sector_number = src->u.indirect.sector_number; + n = min(MAX_INDIRECT_PAGES, + INDIRECT_PAGES(dst->u.indirect.nr_segments)); + for (i = 0; i < n; i++) + dst->u.indirect.indirect_grefs[i] = + src->u.indirect.indirect_grefs[i]; + break; + default: + /* + * Don't know how to translate this op. Only get the + * ID so failure can be reported to the frontend. + */ + dst->u.other.id = src->u.other.id; + break; + } +} /* * Function to copy the from the ring buffer the 'struct blkif_request' |