diff options
Diffstat (limited to 'drivers/block/xen-blkback/blkback.c')
-rw-r--r-- | drivers/block/xen-blkback/blkback.c | 91 |
1 files changed, 53 insertions, 38 deletions
diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c index 74374fb762aa..dd5b2fed97e9 100644 --- a/drivers/block/xen-blkback/blkback.c +++ b/drivers/block/xen-blkback/blkback.c @@ -46,6 +46,7 @@ #include <xen/xen.h> #include <asm/xen/hypervisor.h> #include <asm/xen/hypercall.h> +#include <xen/balloon.h> #include "common.h" /* @@ -161,10 +162,12 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, static void make_response(struct xen_blkif *blkif, u64 id, unsigned short op, int st); -#define foreach_grant(pos, rbtree, node) \ - for ((pos) = container_of(rb_first((rbtree)), typeof(*(pos)), node); \ +#define foreach_grant_safe(pos, n, rbtree, node) \ + for ((pos) = container_of(rb_first((rbtree)), typeof(*(pos)), node), \ + (n) = (&(pos)->node != NULL) ? rb_next(&(pos)->node) : NULL; \ &(pos)->node != NULL; \ - (pos) = container_of(rb_next(&(pos)->node), typeof(*(pos)), node)) + (pos) = container_of(n, typeof(*(pos)), node), \ + (n) = (&(pos)->node != NULL) ? rb_next(&(pos)->node) : NULL) static void add_persistent_gnt(struct rb_root *root, @@ -217,10 +220,11 @@ static void free_persistent_gnts(struct rb_root *root, unsigned int num) struct gnttab_unmap_grant_ref unmap[BLKIF_MAX_SEGMENTS_PER_REQUEST]; struct page *pages[BLKIF_MAX_SEGMENTS_PER_REQUEST]; struct persistent_gnt *persistent_gnt; + struct rb_node *n; int ret = 0; int segs_to_unmap = 0; - foreach_grant(persistent_gnt, root, node) { + foreach_grant_safe(persistent_gnt, n, root, node) { BUG_ON(persistent_gnt->handle == BLKBACK_INVALID_HANDLE); gnttab_set_unmap_op(&unmap[segs_to_unmap], @@ -230,17 +234,19 @@ static void free_persistent_gnts(struct rb_root *root, unsigned int num) persistent_gnt->handle); pages[segs_to_unmap] = persistent_gnt->page; - rb_erase(&persistent_gnt->node, root); - kfree(persistent_gnt); - num--; if (++segs_to_unmap == BLKIF_MAX_SEGMENTS_PER_REQUEST || !rb_next(&persistent_gnt->node)) { ret = gnttab_unmap_refs(unmap, NULL, pages, segs_to_unmap); BUG_ON(ret); + free_xenballooned_pages(segs_to_unmap, pages); segs_to_unmap = 0; } + + rb_erase(&persistent_gnt->node, root); + kfree(persistent_gnt); + num--; } BUG_ON(num != 0); } @@ -375,8 +381,8 @@ irqreturn_t xen_blkif_be_int(int irq, void *dev_id) static void print_stats(struct xen_blkif *blkif) { - pr_info("xen-blkback (%s): oo %3d | rd %4d | wr %4d | f %4d" - " | ds %4d\n", + pr_info("xen-blkback (%s): oo %3llu | rd %4llu | wr %4llu | f %4llu" + " | ds %4llu\n", current->comm, blkif->st_oo_req, blkif->st_rd_req, blkif->st_wr_req, blkif->st_f_req, blkif->st_ds_req); @@ -436,7 +442,7 @@ int xen_blkif_schedule(void *arg) } struct seg_buf { - unsigned long buf; + unsigned int offset; unsigned int nsec; }; /* @@ -523,8 +529,8 @@ static int xen_blkbk_map(struct blkif_request *req, GFP_KERNEL); if (!persistent_gnt) return -ENOMEM; - persistent_gnt->page = alloc_page(GFP_KERNEL); - if (!persistent_gnt->page) { + if (alloc_xenballooned_pages(1, &persistent_gnt->page, + false)) { kfree(persistent_gnt); return -ENOMEM; } @@ -615,30 +621,21 @@ static int xen_blkbk_map(struct blkif_request *req, * If this is a new persistent grant * save the handler */ - persistent_gnts[i]->handle = map[j].handle; - persistent_gnts[i]->dev_bus_addr = - map[j++].dev_bus_addr; + persistent_gnts[i]->handle = map[j++].handle; } pending_handle(pending_req, i) = persistent_gnts[i]->handle; if (ret) continue; - - seg[i].buf = persistent_gnts[i]->dev_bus_addr | - (req->u.rw.seg[i].first_sect << 9); } else { - pending_handle(pending_req, i) = map[j].handle; + pending_handle(pending_req, i) = map[j++].handle; bitmap_set(pending_req->unmap_seg, i, 1); - if (ret) { - j++; + if (ret) continue; - } - - seg[i].buf = map[j++].dev_bus_addr | - (req->u.rw.seg[i].first_sect << 9); } + seg[i].offset = (req->u.rw.seg[i].first_sect << 9); } return ret; } @@ -673,6 +670,16 @@ static int dispatch_discard_io(struct xen_blkif *blkif, return err; } +static int dispatch_other_io(struct xen_blkif *blkif, + struct blkif_request *req, + struct pending_req *pending_req) +{ + free_req(pending_req); + make_response(blkif, req->u.other.id, req->operation, + BLKIF_RSP_EOPNOTSUPP); + return -EIO; +} + static void xen_blk_drain_io(struct xen_blkif *blkif) { atomic_set(&blkif->drain, 1); @@ -794,17 +801,30 @@ __do_block_io_op(struct xen_blkif *blkif) /* Apply all sanity checks to /private copy/ of request. */ barrier(); - if (unlikely(req.operation == BLKIF_OP_DISCARD)) { + + switch (req.operation) { + case BLKIF_OP_READ: + case BLKIF_OP_WRITE: + case BLKIF_OP_WRITE_BARRIER: + case BLKIF_OP_FLUSH_DISKCACHE: + if (dispatch_rw_block_io(blkif, &req, pending_req)) + goto done; + break; + case BLKIF_OP_DISCARD: free_req(pending_req); if (dispatch_discard_io(blkif, &req)) - break; - } else if (dispatch_rw_block_io(blkif, &req, pending_req)) + goto done; + break; + default: + if (dispatch_other_io(blkif, &req, pending_req)) + goto done; break; + } /* Yield point for this unbounded loop. */ cond_resched(); } - +done: return more_to_do; } @@ -875,7 +895,6 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, goto fail_response; } - preq.dev = req->u.rw.handle; preq.sector_number = req->u.rw.sector_number; preq.nr_sects = 0; @@ -899,7 +918,8 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, pr_debug(DRV_PFX "access denied: %s of [%llu,%llu] on dev=%04x\n", operation == READ ? "read" : "write", preq.sector_number, - preq.sector_number + preq.nr_sects, preq.dev); + preq.sector_number + preq.nr_sects, + blkif->vbd.pdevice); goto fail_response; } @@ -942,7 +962,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, (bio_add_page(bio, pages[i], seg[i].nsec << 9, - seg[i].buf & ~PAGE_MASK) == 0)) { + seg[i].offset) == 0)) { bio = bio_alloc(GFP_KERNEL, nseg-i); if (unlikely(bio == NULL)) @@ -972,13 +992,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, bio->bi_end_io = end_block_io_op; } - /* - * We set it one so that the last submit_bio does not have to call - * atomic_inc. - */ atomic_set(&pending_req->pendcnt, nbio); - - /* Get a reference count for the disk queue and start sending I/O */ blk_start_plug(&plug); for (i = 0; i < nbio; i++) @@ -1006,6 +1020,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, fail_put_bio: for (i = 0; i < nbio; i++) bio_put(biolist[i]); + atomic_set(&pending_req->pendcnt, 1); __end_block_io_op(pending_req, -EINVAL); msleep(1); /* back off a bit */ return -EIO; |