diff options
-rw-r--r-- | drivers/block/xen-blkback/blkback.c | 68 | ||||
-rw-r--r-- | drivers/block/xen-blkback/common.h | 40 | ||||
-rw-r--r-- | drivers/block/xen-blkback/xenbus.c | 14 | ||||
-rw-r--r-- | drivers/block/xen-blkfront.c | 154 | ||||
-rw-r--r-- | include/xen/interface/io/blkif.h | 10 |
5 files changed, 179 insertions, 107 deletions
diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c index de1f319f7bd7..dd5b2fed97e9 100644 --- a/drivers/block/xen-blkback/blkback.c +++ b/drivers/block/xen-blkback/blkback.c @@ -164,7 +164,7 @@ static void make_response(struct xen_blkif *blkif, u64 id, #define foreach_grant_safe(pos, n, rbtree, node) \ for ((pos) = container_of(rb_first((rbtree)), typeof(*(pos)), node), \ - (n) = rb_next(&(pos)->node); \ + (n) = (&(pos)->node != NULL) ? rb_next(&(pos)->node) : NULL; \ &(pos)->node != NULL; \ (pos) = container_of(n, typeof(*(pos)), node), \ (n) = (&(pos)->node != NULL) ? rb_next(&(pos)->node) : NULL) @@ -381,8 +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); @@ -442,7 +442,7 @@ int xen_blkif_schedule(void *arg) } struct seg_buf { - unsigned long buf; + unsigned int offset; unsigned int nsec; }; /* @@ -621,30 +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; } @@ -679,6 +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); @@ -800,17 +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; } @@ -904,7 +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; } @@ -947,7 +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)) @@ -977,13 +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++) @@ -1011,6 +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; diff --git a/drivers/block/xen-blkback/common.h b/drivers/block/xen-blkback/common.h index 6072390c7f57..60103e2517ba 100644 --- a/drivers/block/xen-blkback/common.h +++ b/drivers/block/xen-blkback/common.h @@ -77,11 +77,18 @@ struct blkif_x86_32_request_discard { uint64_t nr_sectors; } __attribute__((__packed__)); +struct blkif_x86_32_request_other { + uint8_t _pad1; + blkif_vdev_t _pad2; + uint64_t id; /* private guest value, echoed in resp */ +} __attribute__((__packed__)); + struct blkif_x86_32_request { uint8_t operation; /* BLKIF_OP_??? */ union { struct blkif_x86_32_request_rw rw; struct blkif_x86_32_request_discard discard; + struct blkif_x86_32_request_other other; } u; } __attribute__((__packed__)); @@ -113,11 +120,19 @@ struct blkif_x86_64_request_discard { uint64_t nr_sectors; } __attribute__((__packed__)); +struct blkif_x86_64_request_other { + uint8_t _pad1; + blkif_vdev_t _pad2; + uint32_t _pad3; /* offsetof(blkif_..,u.discard.id)==8 */ + uint64_t id; /* private guest value, echoed in resp */ +} __attribute__((__packed__)); + struct blkif_x86_64_request { uint8_t operation; /* BLKIF_OP_??? */ union { struct blkif_x86_64_request_rw rw; struct blkif_x86_64_request_discard discard; + struct blkif_x86_64_request_other other; } u; } __attribute__((__packed__)); @@ -172,7 +187,6 @@ struct persistent_gnt { struct page *page; grant_ref_t gnt; grant_handle_t handle; - uint64_t dev_bus_addr; struct rb_node node; }; @@ -208,13 +222,13 @@ struct xen_blkif { /* statistics */ unsigned long st_print; - int st_rd_req; - int st_wr_req; - int st_oo_req; - int st_f_req; - int st_ds_req; - int st_rd_sect; - int st_wr_sect; + unsigned long long st_rd_req; + unsigned long long st_wr_req; + unsigned long long st_oo_req; + unsigned long long st_f_req; + unsigned long long st_ds_req; + unsigned long long st_rd_sect; + unsigned long long st_wr_sect; wait_queue_head_t waiting_to_free; }; @@ -278,6 +292,11 @@ static inline void blkif_get_x86_32_req(struct blkif_request *dst, dst->u.discard.nr_sectors = src->u.discard.nr_sectors; 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; } } @@ -309,6 +328,11 @@ static inline void blkif_get_x86_64_req(struct blkif_request *dst, dst->u.discard.nr_sectors = src->u.discard.nr_sectors; 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; } } diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c index 5e237f630c47..8bfd1bcf95ec 100644 --- a/drivers/block/xen-blkback/xenbus.c +++ b/drivers/block/xen-blkback/xenbus.c @@ -230,13 +230,13 @@ int __init xen_blkif_interface_init(void) } \ static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL) -VBD_SHOW(oo_req, "%d\n", be->blkif->st_oo_req); -VBD_SHOW(rd_req, "%d\n", be->blkif->st_rd_req); -VBD_SHOW(wr_req, "%d\n", be->blkif->st_wr_req); -VBD_SHOW(f_req, "%d\n", be->blkif->st_f_req); -VBD_SHOW(ds_req, "%d\n", be->blkif->st_ds_req); -VBD_SHOW(rd_sect, "%d\n", be->blkif->st_rd_sect); -VBD_SHOW(wr_sect, "%d\n", be->blkif->st_wr_sect); +VBD_SHOW(oo_req, "%llu\n", be->blkif->st_oo_req); +VBD_SHOW(rd_req, "%llu\n", be->blkif->st_rd_req); +VBD_SHOW(wr_req, "%llu\n", be->blkif->st_wr_req); +VBD_SHOW(f_req, "%llu\n", be->blkif->st_f_req); +VBD_SHOW(ds_req, "%llu\n", be->blkif->st_ds_req); +VBD_SHOW(rd_sect, "%llu\n", be->blkif->st_rd_sect); +VBD_SHOW(wr_sect, "%llu\n", be->blkif->st_wr_sect); static struct attribute *xen_vbdstat_attrs[] = { &dev_attr_oo_req.attr, diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c index c3dae2e0f290..a894f88762d8 100644 --- a/drivers/block/xen-blkfront.c +++ b/drivers/block/xen-blkfront.c @@ -44,7 +44,7 @@ #include <linux/mutex.h> #include <linux/scatterlist.h> #include <linux/bitmap.h> -#include <linux/llist.h> +#include <linux/list.h> #include <xen/xen.h> #include <xen/xenbus.h> @@ -68,13 +68,12 @@ enum blkif_state { struct grant { grant_ref_t gref; unsigned long pfn; - struct llist_node node; + struct list_head node; }; struct blk_shadow { struct blkif_request req; struct request *request; - unsigned long frame[BLKIF_MAX_SEGMENTS_PER_REQUEST]; struct grant *grants_used[BLKIF_MAX_SEGMENTS_PER_REQUEST]; }; @@ -105,7 +104,7 @@ struct blkfront_info struct work_struct work; struct gnttab_free_callback callback; struct blk_shadow shadow[BLK_RING_SIZE]; - struct llist_head persistent_gnts; + struct list_head persistent_gnts; unsigned int persistent_gnts_c; unsigned long shadow_free; unsigned int feature_flush; @@ -165,6 +164,69 @@ static int add_id_to_freelist(struct blkfront_info *info, return 0; } +static int fill_grant_buffer(struct blkfront_info *info, int num) +{ + struct page *granted_page; + struct grant *gnt_list_entry, *n; + int i = 0; + + while(i < num) { + gnt_list_entry = kzalloc(sizeof(struct grant), GFP_NOIO); + if (!gnt_list_entry) + goto out_of_memory; + + granted_page = alloc_page(GFP_NOIO); + if (!granted_page) { + kfree(gnt_list_entry); + goto out_of_memory; + } + + gnt_list_entry->pfn = page_to_pfn(granted_page); + gnt_list_entry->gref = GRANT_INVALID_REF; + list_add(&gnt_list_entry->node, &info->persistent_gnts); + i++; + } + + return 0; + +out_of_memory: + list_for_each_entry_safe(gnt_list_entry, n, + &info->persistent_gnts, node) { + list_del(&gnt_list_entry->node); + __free_page(pfn_to_page(gnt_list_entry->pfn)); + kfree(gnt_list_entry); + i--; + } + BUG_ON(i != 0); + return -ENOMEM; +} + +static struct grant *get_grant(grant_ref_t *gref_head, + struct blkfront_info *info) +{ + struct grant *gnt_list_entry; + unsigned long buffer_mfn; + + BUG_ON(list_empty(&info->persistent_gnts)); + gnt_list_entry = list_first_entry(&info->persistent_gnts, struct grant, + node); + list_del(&gnt_list_entry->node); + + if (gnt_list_entry->gref != GRANT_INVALID_REF) { + info->persistent_gnts_c--; + return gnt_list_entry; + } + + /* Assign a gref to this page */ + gnt_list_entry->gref = gnttab_claim_grant_reference(gref_head); + BUG_ON(gnt_list_entry->gref == -ENOSPC); + buffer_mfn = pfn_to_mfn(gnt_list_entry->pfn); + gnttab_grant_foreign_access_ref(gnt_list_entry->gref, + info->xbdev->otherend_id, + buffer_mfn, 0); + return gnt_list_entry; +} + static const char *op_name(int op) { static const char *const names[] = { @@ -293,7 +355,6 @@ static int blkif_ioctl(struct block_device *bdev, fmode_t mode, static int blkif_queue_request(struct request *req) { struct blkfront_info *info = req->rq_disk->private_data; - unsigned long buffer_mfn; struct blkif_request *ring_req; unsigned long id; unsigned int fsect, lsect; @@ -306,7 +367,6 @@ static int blkif_queue_request(struct request *req) */ bool new_persistent_gnts; grant_ref_t gref_head; - struct page *granted_page; struct grant *gnt_list_entry = NULL; struct scatterlist *sg; @@ -370,41 +430,8 @@ static int blkif_queue_request(struct request *req) fsect = sg->offset >> 9; lsect = fsect + (sg->length >> 9) - 1; - if (info->persistent_gnts_c) { - BUG_ON(llist_empty(&info->persistent_gnts)); - gnt_list_entry = llist_entry( - llist_del_first(&info->persistent_gnts), - struct grant, node); - - ref = gnt_list_entry->gref; - buffer_mfn = pfn_to_mfn(gnt_list_entry->pfn); - info->persistent_gnts_c--; - } else { - ref = gnttab_claim_grant_reference(&gref_head); - BUG_ON(ref == -ENOSPC); - - gnt_list_entry = - kmalloc(sizeof(struct grant), - GFP_ATOMIC); - if (!gnt_list_entry) - return -ENOMEM; - - granted_page = alloc_page(GFP_ATOMIC); - if (!granted_page) { - kfree(gnt_list_entry); - return -ENOMEM; - } - - gnt_list_entry->pfn = - page_to_pfn(granted_page); - gnt_list_entry->gref = ref; - - buffer_mfn = pfn_to_mfn(page_to_pfn( - granted_page)); - gnttab_grant_foreign_access_ref(ref, - info->xbdev->otherend_id, - buffer_mfn, 0); - } + gnt_list_entry = get_grant(&gref_head, info); + ref = gnt_list_entry->gref; info->shadow[id].grants_used[i] = gnt_list_entry; @@ -435,7 +462,6 @@ static int blkif_queue_request(struct request *req) kunmap_atomic(shared_data); } - info->shadow[id].frame[i] = mfn_to_pfn(buffer_mfn); ring_req->u.rw.seg[i] = (struct blkif_request_segment) { .gref = ref, @@ -790,9 +816,8 @@ static void blkif_restart_queue(struct work_struct *work) static void blkif_free(struct blkfront_info *info, int suspend) { - struct llist_node *all_gnts; - struct grant *persistent_gnt, *tmp; - struct llist_node *n; + struct grant *persistent_gnt; + struct grant *n; /* Prevent new requests being issued until we fix things up. */ spin_lock_irq(&info->io_lock); @@ -803,22 +828,20 @@ static void blkif_free(struct blkfront_info *info, int suspend) blk_stop_queue(info->rq); /* Remove all persistent grants */ - if (info->persistent_gnts_c) { - all_gnts = llist_del_all(&info->persistent_gnts); - persistent_gnt = llist_entry(all_gnts, typeof(*(persistent_gnt)), node); - while (persistent_gnt) { - gnttab_end_foreign_access(persistent_gnt->gref, 0, 0UL); + if (!list_empty(&info->persistent_gnts)) { + list_for_each_entry_safe(persistent_gnt, n, + &info->persistent_gnts, node) { + list_del(&persistent_gnt->node); + if (persistent_gnt->gref != GRANT_INVALID_REF) { + gnttab_end_foreign_access(persistent_gnt->gref, + 0, 0UL); + info->persistent_gnts_c--; + } __free_page(pfn_to_page(persistent_gnt->pfn)); - tmp = persistent_gnt; - n = persistent_gnt->node.next; - if (n) - persistent_gnt = llist_entry(n, typeof(*(persistent_gnt)), node); - else - persistent_gnt = NULL; - kfree(tmp); + kfree(persistent_gnt); } - info->persistent_gnts_c = 0; } + BUG_ON(info->persistent_gnts_c != 0); /* No more gnttab callback work. */ gnttab_cancel_free_callback(&info->callback); @@ -875,7 +898,7 @@ static void blkif_completion(struct blk_shadow *s, struct blkfront_info *info, } /* Add the persistent grant into the list of free grants */ for (i = 0; i < s->req.u.rw.nr_segments; i++) { - llist_add(&s->grants_used[i]->node, &info->persistent_gnts); + list_add(&s->grants_used[i]->node, &info->persistent_gnts); info->persistent_gnts_c++; } } @@ -1013,6 +1036,12 @@ static int setup_blkring(struct xenbus_device *dev, sg_init_table(info->sg, BLKIF_MAX_SEGMENTS_PER_REQUEST); + /* Allocate memory for grants */ + err = fill_grant_buffer(info, BLK_RING_SIZE * + BLKIF_MAX_SEGMENTS_PER_REQUEST); + if (err) + goto fail; + err = xenbus_grant_ring(dev, virt_to_mfn(info->ring.sring)); if (err < 0) { free_page((unsigned long)sring); @@ -1171,7 +1200,7 @@ static int blkfront_probe(struct xenbus_device *dev, spin_lock_init(&info->io_lock); info->xbdev = dev; info->vdevice = vdevice; - init_llist_head(&info->persistent_gnts); + INIT_LIST_HEAD(&info->persistent_gnts); info->persistent_gnts_c = 0; info->connected = BLKIF_STATE_DISCONNECTED; INIT_WORK(&info->work, blkif_restart_queue); @@ -1203,11 +1232,10 @@ static int blkif_recover(struct blkfront_info *info) int j; /* Stage 1: Make a safe copy of the shadow state. */ - copy = kmalloc(sizeof(info->shadow), + copy = kmemdup(info->shadow, sizeof(info->shadow), GFP_NOIO | __GFP_REPEAT | __GFP_HIGH); if (!copy) return -ENOMEM; - memcpy(copy, info->shadow, sizeof(info->shadow)); /* Stage 2: Set up free list. */ memset(&info->shadow, 0, sizeof(info->shadow)); @@ -1236,7 +1264,7 @@ static int blkif_recover(struct blkfront_info *info) gnttab_grant_foreign_access_ref( req->u.rw.seg[j].gref, info->xbdev->otherend_id, - pfn_to_mfn(info->shadow[req->u.rw.id].frame[j]), + pfn_to_mfn(copy[i].grants_used[j]->pfn), 0); } info->shadow[req->u.rw.id].req = *req; diff --git a/include/xen/interface/io/blkif.h b/include/xen/interface/io/blkif.h index 01c3d62436ef..ffd4652de91c 100644 --- a/include/xen/interface/io/blkif.h +++ b/include/xen/interface/io/blkif.h @@ -138,11 +138,21 @@ struct blkif_request_discard { uint8_t _pad3; } __attribute__((__packed__)); +struct blkif_request_other { + uint8_t _pad1; + blkif_vdev_t _pad2; /* only for read/write requests */ +#ifdef CONFIG_X86_64 + uint32_t _pad3; /* offsetof(blkif_req..,u.other.id)==8*/ +#endif + uint64_t id; /* private guest value, echoed in resp */ +} __attribute__((__packed__)); + struct blkif_request { uint8_t operation; /* BLKIF_OP_??? */ union { struct blkif_request_rw rw; struct blkif_request_discard discard; + struct blkif_request_other other; } u; } __attribute__((__packed__)); |