From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753161AbbIEMnB (ORCPT ); Sat, 5 Sep 2015 08:43:01 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:43741 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750810AbbIEMlI (ORCPT ); Sat, 5 Sep 2015 08:41:08 -0400 From: Bob Liu To: xen-devel@lists.xen.org Cc: david.vrabel@citrix.com, linux-kernel@vger.kernel.org, roger.pau@citrix.com, konrad.wilk@oracle.com, felipe.franciosi@citrix.com, axboe@fb.com, hch@infradead.org, avanzini.arianna@gmail.com, rafal.mielniczuk@citrix.com, boris.ostrovsky@oracle.com, jonathan.davies@citrix.com, Bob Liu Subject: [PATCH v3 7/9] xen/blkback: separate ring information out of struct xen_blkif Date: Sat, 5 Sep 2015 20:39:40 +0800 Message-Id: <1441456782-31318-8-git-send-email-bob.liu@oracle.com> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1441456782-31318-1-git-send-email-bob.liu@oracle.com> References: <1441456782-31318-1-git-send-email-bob.liu@oracle.com> X-Source-IP: aserv0021.oracle.com [141.146.126.233] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Split per ring information to an new structure:xen_blkif_ring, so that one vbd device can associate with one or more rings/hardware queues. This patch is a preparation for supporting multi hardware queues/rings. Signed-off-by: Arianna Avanzini Signed-off-by: Bob Liu --- drivers/block/xen-blkback/blkback.c | 365 ++++++++++++++++++----------------- drivers/block/xen-blkback/common.h | 52 +++-- drivers/block/xen-blkback/xenbus.c | 130 +++++++------ 3 files changed, 295 insertions(+), 252 deletions(-) diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c index 954c002..fd02240 100644 --- a/drivers/block/xen-blkback/blkback.c +++ b/drivers/block/xen-blkback/blkback.c @@ -113,71 +113,71 @@ module_param(log_stats, int, 0644); /* Number of free pages to remove on each call to gnttab_free_pages */ #define NUM_BATCH_FREE_PAGES 10 -static inline int get_free_page(struct xen_blkif *blkif, struct page **page) +static inline int get_free_page(struct xen_blkif_ring *ring, struct page **page) { unsigned long flags; - spin_lock_irqsave(&blkif->free_pages_lock, flags); - if (list_empty(&blkif->free_pages)) { - BUG_ON(blkif->free_pages_num != 0); - spin_unlock_irqrestore(&blkif->free_pages_lock, flags); + spin_lock_irqsave(&ring->free_pages_lock, flags); + if (list_empty(&ring->free_pages)) { + BUG_ON(ring->free_pages_num != 0); + spin_unlock_irqrestore(&ring->free_pages_lock, flags); return gnttab_alloc_pages(1, page); } - BUG_ON(blkif->free_pages_num == 0); - page[0] = list_first_entry(&blkif->free_pages, struct page, lru); + BUG_ON(ring->free_pages_num == 0); + page[0] = list_first_entry(&ring->free_pages, struct page, lru); list_del(&page[0]->lru); - blkif->free_pages_num--; - spin_unlock_irqrestore(&blkif->free_pages_lock, flags); + ring->free_pages_num--; + spin_unlock_irqrestore(&ring->free_pages_lock, flags); return 0; } -static inline void put_free_pages(struct xen_blkif *blkif, struct page **page, +static inline void put_free_pages(struct xen_blkif_ring *ring, struct page **page, int num) { unsigned long flags; int i; - spin_lock_irqsave(&blkif->free_pages_lock, flags); + spin_lock_irqsave(&ring->free_pages_lock, flags); for (i = 0; i < num; i++) - list_add(&page[i]->lru, &blkif->free_pages); - blkif->free_pages_num += num; - spin_unlock_irqrestore(&blkif->free_pages_lock, flags); + list_add(&page[i]->lru, &ring->free_pages); + ring->free_pages_num += num; + spin_unlock_irqrestore(&ring->free_pages_lock, flags); } -static inline void shrink_free_pagepool(struct xen_blkif *blkif, int num) +static inline void shrink_free_pagepool(struct xen_blkif_ring *ring, int num) { /* Remove requested pages in batches of NUM_BATCH_FREE_PAGES */ struct page *page[NUM_BATCH_FREE_PAGES]; unsigned int num_pages = 0; unsigned long flags; - spin_lock_irqsave(&blkif->free_pages_lock, flags); - while (blkif->free_pages_num > num) { - BUG_ON(list_empty(&blkif->free_pages)); - page[num_pages] = list_first_entry(&blkif->free_pages, + spin_lock_irqsave(&ring->free_pages_lock, flags); + while (ring->free_pages_num > num) { + BUG_ON(list_empty(&ring->free_pages)); + page[num_pages] = list_first_entry(&ring->free_pages, struct page, lru); list_del(&page[num_pages]->lru); - blkif->free_pages_num--; + ring->free_pages_num--; if (++num_pages == NUM_BATCH_FREE_PAGES) { - spin_unlock_irqrestore(&blkif->free_pages_lock, flags); + spin_unlock_irqrestore(&ring->free_pages_lock, flags); gnttab_free_pages(num_pages, page); - spin_lock_irqsave(&blkif->free_pages_lock, flags); + spin_lock_irqsave(&ring->free_pages_lock, flags); num_pages = 0; } } - spin_unlock_irqrestore(&blkif->free_pages_lock, flags); + spin_unlock_irqrestore(&ring->free_pages_lock, flags); if (num_pages != 0) gnttab_free_pages(num_pages, page); } #define vaddr(page) ((unsigned long)pfn_to_kaddr(page_to_pfn(page))) -static int do_block_io_op(struct xen_blkif *blkif); -static int dispatch_rw_block_io(struct xen_blkif *blkif, +static int do_block_io_op(struct xen_blkif_ring *ring); +static int dispatch_rw_block_io(struct xen_blkif_ring *ring, struct blkif_request *req, struct pending_req *pending_req); -static void make_response(struct xen_blkif *blkif, u64 id, +static void make_response(struct xen_blkif_ring *ring, u64 id, unsigned short op, int st); #define foreach_grant_safe(pos, n, rbtree, node) \ @@ -198,19 +198,19 @@ static void make_response(struct xen_blkif *blkif, u64 id, * bit operations to modify the flags of a persistent grant and to count * the number of used grants. */ -static int add_persistent_gnt(struct xen_blkif *blkif, +static int add_persistent_gnt(struct xen_blkif_ring *ring, struct persistent_gnt *persistent_gnt) { struct rb_node **new = NULL, *parent = NULL; struct persistent_gnt *this; - if (blkif->persistent_gnt_c >= xen_blkif_max_pgrants) { - if (!blkif->vbd.overflow_max_grants) - blkif->vbd.overflow_max_grants = 1; + if (ring->persistent_gnt_c >= xen_blkif_max_pgrants) { + if (!ring->blkif->vbd.overflow_max_grants) + ring->blkif->vbd.overflow_max_grants = 1; return -EBUSY; } /* Figure out where to put new node */ - new = &blkif->persistent_gnts.rb_node; + new = &ring->persistent_gnts.rb_node; while (*new) { this = container_of(*new, struct persistent_gnt, node); @@ -229,19 +229,19 @@ static int add_persistent_gnt(struct xen_blkif *blkif, set_bit(PERSISTENT_GNT_ACTIVE, persistent_gnt->flags); /* Add new node and rebalance tree. */ rb_link_node(&(persistent_gnt->node), parent, new); - rb_insert_color(&(persistent_gnt->node), &blkif->persistent_gnts); - blkif->persistent_gnt_c++; - atomic_inc(&blkif->persistent_gnt_in_use); + rb_insert_color(&(persistent_gnt->node), &ring->persistent_gnts); + ring->persistent_gnt_c++; + atomic_inc(&ring->persistent_gnt_in_use); return 0; } -static struct persistent_gnt *get_persistent_gnt(struct xen_blkif *blkif, - grant_ref_t gref) +static struct persistent_gnt *get_persistent_gnt(struct xen_blkif_ring *ring, + grant_ref_t gref) { struct persistent_gnt *data; struct rb_node *node = NULL; - node = blkif->persistent_gnts.rb_node; + node = ring->persistent_gnts.rb_node; while (node) { data = container_of(node, struct persistent_gnt, node); @@ -255,24 +255,24 @@ static struct persistent_gnt *get_persistent_gnt(struct xen_blkif *blkif, return NULL; } set_bit(PERSISTENT_GNT_ACTIVE, data->flags); - atomic_inc(&blkif->persistent_gnt_in_use); + atomic_inc(&ring->persistent_gnt_in_use); return data; } } return NULL; } -static void put_persistent_gnt(struct xen_blkif *blkif, +static void put_persistent_gnt(struct xen_blkif_ring *ring, struct persistent_gnt *persistent_gnt) { if(!test_bit(PERSISTENT_GNT_ACTIVE, persistent_gnt->flags)) pr_alert_ratelimited("freeing a grant already unused\n"); set_bit(PERSISTENT_GNT_WAS_ACTIVE, persistent_gnt->flags); clear_bit(PERSISTENT_GNT_ACTIVE, persistent_gnt->flags); - atomic_dec(&blkif->persistent_gnt_in_use); + atomic_dec(&ring->persistent_gnt_in_use); } -static void free_persistent_gnts(struct xen_blkif *blkif, struct rb_root *root, +static void free_persistent_gnts(struct xen_blkif_ring *ring, struct rb_root *root, unsigned int num) { struct gnttab_unmap_grant_ref unmap[BLKIF_MAX_SEGMENTS_PER_REQUEST]; @@ -303,7 +303,7 @@ static void free_persistent_gnts(struct xen_blkif *blkif, struct rb_root *root, unmap_data.count = segs_to_unmap; BUG_ON(gnttab_unmap_refs_sync(&unmap_data)); - put_free_pages(blkif, pages, segs_to_unmap); + put_free_pages(ring, pages, segs_to_unmap); segs_to_unmap = 0; } @@ -320,15 +320,15 @@ void xen_blkbk_unmap_purged_grants(struct work_struct *work) struct page *pages[BLKIF_MAX_SEGMENTS_PER_REQUEST]; struct persistent_gnt *persistent_gnt; int segs_to_unmap = 0; - struct xen_blkif *blkif = container_of(work, typeof(*blkif), persistent_purge_work); + struct xen_blkif_ring *ring = container_of(work, typeof(*ring), persistent_purge_work); struct gntab_unmap_queue_data unmap_data; unmap_data.pages = pages; unmap_data.unmap_ops = unmap; unmap_data.kunmap_ops = NULL; - while(!list_empty(&blkif->persistent_purge_list)) { - persistent_gnt = list_first_entry(&blkif->persistent_purge_list, + while(!list_empty(&ring->persistent_purge_list)) { + persistent_gnt = list_first_entry(&ring->persistent_purge_list, struct persistent_gnt, remove_node); list_del(&persistent_gnt->remove_node); @@ -343,7 +343,7 @@ void xen_blkbk_unmap_purged_grants(struct work_struct *work) if (++segs_to_unmap == BLKIF_MAX_SEGMENTS_PER_REQUEST) { unmap_data.count = segs_to_unmap; BUG_ON(gnttab_unmap_refs_sync(&unmap_data)); - put_free_pages(blkif, pages, segs_to_unmap); + put_free_pages(ring, pages, segs_to_unmap); segs_to_unmap = 0; } kfree(persistent_gnt); @@ -351,34 +351,35 @@ void xen_blkbk_unmap_purged_grants(struct work_struct *work) if (segs_to_unmap > 0) { unmap_data.count = segs_to_unmap; BUG_ON(gnttab_unmap_refs_sync(&unmap_data)); - put_free_pages(blkif, pages, segs_to_unmap); + put_free_pages(ring, pages, segs_to_unmap); } } -static void purge_persistent_gnt(struct xen_blkif *blkif) +static void purge_persistent_gnt(struct xen_blkif_ring *ring) { struct persistent_gnt *persistent_gnt; struct rb_node *n; unsigned int num_clean, total; bool scan_used = false, clean_used = false; struct rb_root *root; + struct xen_blkif *blkif = ring->blkif; - if (blkif->persistent_gnt_c < xen_blkif_max_pgrants || - (blkif->persistent_gnt_c == xen_blkif_max_pgrants && + if (ring->persistent_gnt_c < xen_blkif_max_pgrants || + (ring->persistent_gnt_c == xen_blkif_max_pgrants && !blkif->vbd.overflow_max_grants)) { return; } - if (work_busy(&blkif->persistent_purge_work)) { + if (work_busy(&ring->persistent_purge_work)) { pr_alert_ratelimited("Scheduled work from previous purge is still busy, cannot purge list\n"); return; } num_clean = (xen_blkif_max_pgrants / 100) * LRU_PERCENT_CLEAN; - num_clean = blkif->persistent_gnt_c - xen_blkif_max_pgrants + num_clean; - num_clean = min(blkif->persistent_gnt_c, num_clean); + num_clean = ring->persistent_gnt_c - xen_blkif_max_pgrants + num_clean; + num_clean = min(ring->persistent_gnt_c, num_clean); if ((num_clean == 0) || - (num_clean > (blkif->persistent_gnt_c - atomic_read(&blkif->persistent_gnt_in_use)))) + (num_clean > (ring->persistent_gnt_c - atomic_read(&ring->persistent_gnt_in_use)))) return; /* @@ -394,8 +395,8 @@ static void purge_persistent_gnt(struct xen_blkif *blkif) pr_debug("Going to purge %u persistent grants\n", num_clean); - BUG_ON(!list_empty(&blkif->persistent_purge_list)); - root = &blkif->persistent_gnts; + BUG_ON(!list_empty(&ring->persistent_purge_list)); + root = &ring->persistent_gnts; purge_list: foreach_grant_safe(persistent_gnt, n, root, node) { BUG_ON(persistent_gnt->handle == @@ -414,7 +415,7 @@ purge_list: rb_erase(&persistent_gnt->node, root); list_add(&persistent_gnt->remove_node, - &blkif->persistent_purge_list); + &ring->persistent_purge_list); if (--num_clean == 0) goto finished; } @@ -435,11 +436,11 @@ finished: goto purge_list; } - blkif->persistent_gnt_c -= (total - num_clean); + ring->persistent_gnt_c -= (total - num_clean); blkif->vbd.overflow_max_grants = 0; /* We can defer this work */ - schedule_work(&blkif->persistent_purge_work); + schedule_work(&ring->persistent_purge_work); pr_debug("Purged %u/%u\n", (total - num_clean), total); return; } @@ -447,18 +448,18 @@ finished: /* * Retrieve from the 'pending_reqs' a free pending_req structure to be used. */ -static struct pending_req *alloc_req(struct xen_blkif *blkif) +static struct pending_req *alloc_req(struct xen_blkif_ring *ring) { struct pending_req *req = NULL; unsigned long flags; - spin_lock_irqsave(&blkif->pending_free_lock, flags); - if (!list_empty(&blkif->pending_free)) { - req = list_entry(blkif->pending_free.next, struct pending_req, + spin_lock_irqsave(&ring->pending_free_lock, flags); + if (!list_empty(&ring->pending_free)) { + req = list_entry(ring->pending_free.next, struct pending_req, free_list); list_del(&req->free_list); } - spin_unlock_irqrestore(&blkif->pending_free_lock, flags); + spin_unlock_irqrestore(&ring->pending_free_lock, flags); return req; } @@ -466,17 +467,17 @@ static struct pending_req *alloc_req(struct xen_blkif *blkif) * Return the 'pending_req' structure back to the freepool. We also * wake up the thread if it was waiting for a free page. */ -static void free_req(struct xen_blkif *blkif, struct pending_req *req) +static void free_req(struct xen_blkif_ring *ring, struct pending_req *req) { unsigned long flags; int was_empty; - spin_lock_irqsave(&blkif->pending_free_lock, flags); - was_empty = list_empty(&blkif->pending_free); - list_add(&req->free_list, &blkif->pending_free); - spin_unlock_irqrestore(&blkif->pending_free_lock, flags); + spin_lock_irqsave(&ring->pending_free_lock, flags); + was_empty = list_empty(&ring->pending_free); + list_add(&req->free_list, &ring->pending_free); + spin_unlock_irqrestore(&ring->pending_free_lock, flags); if (was_empty) - wake_up(&blkif->pending_free_wq); + wake_up(&ring->pending_free_wq); } /* @@ -556,10 +557,10 @@ abort: /* * Notification from the guest OS. */ -static void blkif_notify_work(struct xen_blkif *blkif) +static void blkif_notify_work(struct xen_blkif_ring *ring) { - blkif->waiting_reqs = 1; - wake_up(&blkif->wq); + ring->waiting_reqs = 1; + wake_up(&ring->wq); } irqreturn_t xen_blkif_be_int(int irq, void *dev_id) @@ -572,25 +573,26 @@ irqreturn_t xen_blkif_be_int(int irq, void *dev_id) * SCHEDULER FUNCTIONS */ -static void print_stats(struct xen_blkif *blkif) +static void print_stats(struct xen_blkif_ring *ring) { pr_info("(%s): oo %3llu | rd %4llu | wr %4llu | f %4llu" " | ds %4llu | pg: %4u/%4d\n", - current->comm, blkif->st_oo_req, - blkif->st_rd_req, blkif->st_wr_req, - blkif->st_f_req, blkif->st_ds_req, - blkif->persistent_gnt_c, + current->comm, ring->st_oo_req, + ring->st_rd_req, ring->st_wr_req, + ring->st_f_req, ring->st_ds_req, + ring->persistent_gnt_c, xen_blkif_max_pgrants); - blkif->st_print = jiffies + msecs_to_jiffies(10 * 1000); - blkif->st_rd_req = 0; - blkif->st_wr_req = 0; - blkif->st_oo_req = 0; - blkif->st_ds_req = 0; + ring->st_print = jiffies + msecs_to_jiffies(10 * 1000); + ring->st_rd_req = 0; + ring->st_wr_req = 0; + ring->st_oo_req = 0; + ring->st_ds_req = 0; } int xen_blkif_schedule(void *arg) { - struct xen_blkif *blkif = arg; + struct xen_blkif_ring *ring = arg; + struct xen_blkif *blkif = ring->blkif; struct xen_vbd *vbd = &blkif->vbd; unsigned long timeout; int ret; @@ -606,50 +608,50 @@ int xen_blkif_schedule(void *arg) timeout = msecs_to_jiffies(LRU_INTERVAL); timeout = wait_event_interruptible_timeout( - blkif->wq, - blkif->waiting_reqs || kthread_should_stop(), + ring->wq, + ring->waiting_reqs || kthread_should_stop(), timeout); if (timeout == 0) goto purge_gnt_list; timeout = wait_event_interruptible_timeout( - blkif->pending_free_wq, - !list_empty(&blkif->pending_free) || + ring->pending_free_wq, + !list_empty(&ring->pending_free) || kthread_should_stop(), timeout); if (timeout == 0) goto purge_gnt_list; - blkif->waiting_reqs = 0; + ring->waiting_reqs = 0; smp_mb(); /* clear flag *before* checking for work */ - ret = do_block_io_op(blkif); + ret = do_block_io_op(ring); if (ret > 0) - blkif->waiting_reqs = 1; + ring->waiting_reqs = 1; if (ret == -EACCES) - wait_event_interruptible(blkif->shutdown_wq, + wait_event_interruptible(ring->shutdown_wq, kthread_should_stop()); purge_gnt_list: if (blkif->vbd.feature_gnt_persistent && - time_after(jiffies, blkif->next_lru)) { - purge_persistent_gnt(blkif); - blkif->next_lru = jiffies + msecs_to_jiffies(LRU_INTERVAL); + time_after(jiffies, ring->next_lru)) { + purge_persistent_gnt(ring); + ring->next_lru = jiffies + msecs_to_jiffies(LRU_INTERVAL); } /* Shrink if we have more than xen_blkif_max_buffer_pages */ - shrink_free_pagepool(blkif, xen_blkif_max_buffer_pages); + shrink_free_pagepool(ring, xen_blkif_max_buffer_pages); - if (log_stats && time_after(jiffies, blkif->st_print)) - print_stats(blkif); + if (log_stats && time_after(jiffies, ring->st_print)) + print_stats(ring); } /* Drain pending purge work */ - flush_work(&blkif->persistent_purge_work); + flush_work(&ring->persistent_purge_work); if (log_stats) - print_stats(blkif); + print_stats(ring); - blkif->xenblkd = NULL; + ring->xenblkd = NULL; xen_blkif_put(blkif); return 0; @@ -658,22 +660,22 @@ purge_gnt_list: /* * Remove persistent grants and empty the pool of free pages */ -void xen_blkbk_free_caches(struct xen_blkif *blkif) +void xen_blkbk_free_caches(struct xen_blkif_ring *ring) { /* Free all persistent grant pages */ - if (!RB_EMPTY_ROOT(&blkif->persistent_gnts)) - free_persistent_gnts(blkif, &blkif->persistent_gnts, - blkif->persistent_gnt_c); + if (!RB_EMPTY_ROOT(&ring->persistent_gnts)) + free_persistent_gnts(ring, &ring->persistent_gnts, + ring->persistent_gnt_c); - BUG_ON(!RB_EMPTY_ROOT(&blkif->persistent_gnts)); - blkif->persistent_gnt_c = 0; + BUG_ON(!RB_EMPTY_ROOT(&ring->persistent_gnts)); + ring->persistent_gnt_c = 0; /* Since we are shutting down remove all pages from the buffer */ - shrink_free_pagepool(blkif, 0 /* All */); + shrink_free_pagepool(ring, 0 /* All */); } static unsigned int xen_blkbk_unmap_prepare( - struct xen_blkif *blkif, + struct xen_blkif_ring *ring, struct grant_page **pages, unsigned int num, struct gnttab_unmap_grant_ref *unmap_ops, @@ -683,7 +685,7 @@ static unsigned int xen_blkbk_unmap_prepare( for (i = 0; i < num; i++) { if (pages[i]->persistent_gnt != NULL) { - put_persistent_gnt(blkif, pages[i]->persistent_gnt); + put_persistent_gnt(ring, pages[i]->persistent_gnt); continue; } if (pages[i]->handle == BLKBACK_INVALID_HANDLE) @@ -700,17 +702,18 @@ static unsigned int xen_blkbk_unmap_prepare( static void xen_blkbk_unmap_and_respond_callback(int result, struct gntab_unmap_queue_data *data) { - struct pending_req* pending_req = (struct pending_req*) (data->data); - struct xen_blkif *blkif = pending_req->blkif; + struct pending_req *pending_req = (struct pending_req *)(data->data); + struct xen_blkif_ring *ring = pending_req->ring; + struct xen_blkif *blkif = ring->blkif; /* BUG_ON used to reproduce existing behaviour, but is this the best way to deal with this? */ BUG_ON(result); - put_free_pages(blkif, data->pages, data->count); - make_response(blkif, pending_req->id, + put_free_pages(ring, data->pages, data->count); + make_response(ring, pending_req->id, pending_req->operation, pending_req->status); - free_req(blkif, pending_req); + free_req(ring, pending_req); /* * Make sure the request is freed before releasing blkif, * or there could be a race between free_req and the @@ -723,7 +726,7 @@ static void xen_blkbk_unmap_and_respond_callback(int result, struct gntab_unmap_ * pending_free_wq if there's a drain going on, but it has * to be taken into account if the current model is changed. */ - if (atomic_dec_and_test(&blkif->inflight) && atomic_read(&blkif->drain)) { + if (atomic_dec_and_test(&ring->inflight) && atomic_read(&blkif->drain)) { complete(&blkif->drain_complete); } xen_blkif_put(blkif); @@ -732,11 +735,11 @@ static void xen_blkbk_unmap_and_respond_callback(int result, struct gntab_unmap_ static void xen_blkbk_unmap_and_respond(struct pending_req *req) { struct gntab_unmap_queue_data* work = &req->gnttab_unmap_data; - struct xen_blkif *blkif = req->blkif; + struct xen_blkif_ring *ring = req->ring; struct grant_page **pages = req->segments; unsigned int invcount; - invcount = xen_blkbk_unmap_prepare(blkif, pages, req->nr_segs, + invcount = xen_blkbk_unmap_prepare(ring, pages, req->nr_segs, req->unmap, req->unmap_pages); work->data = req; @@ -757,7 +760,7 @@ static void xen_blkbk_unmap_and_respond(struct pending_req *req) * of hypercalls, but since this is only used in error paths there's * no real need. */ -static void xen_blkbk_unmap(struct xen_blkif *blkif, +static void xen_blkbk_unmap(struct xen_blkif_ring *ring, struct grant_page *pages[], int num) { @@ -768,20 +771,20 @@ static void xen_blkbk_unmap(struct xen_blkif *blkif, while (num) { unsigned int batch = min(num, BLKIF_MAX_SEGMENTS_PER_REQUEST); - - invcount = xen_blkbk_unmap_prepare(blkif, pages, batch, + + invcount = xen_blkbk_unmap_prepare(ring, pages, batch, unmap, unmap_pages); if (invcount) { ret = gnttab_unmap_refs(unmap, NULL, unmap_pages, invcount); BUG_ON(ret); - put_free_pages(blkif, unmap_pages, invcount); + put_free_pages(ring, unmap_pages, invcount); } pages += batch; num -= batch; } } -static int xen_blkbk_map(struct xen_blkif *blkif, +static int xen_blkbk_map(struct xen_blkif_ring *ring, struct grant_page *pages[], int num, bool ro) { @@ -794,6 +797,7 @@ static int xen_blkbk_map(struct xen_blkif *blkif, int ret = 0; int last_map = 0, map_until = 0; int use_persistent_gnts; + struct xen_blkif *blkif = ring->blkif; use_persistent_gnts = (blkif->vbd.feature_gnt_persistent); @@ -808,7 +812,7 @@ again: if (use_persistent_gnts) persistent_gnt = get_persistent_gnt( - blkif, + ring, pages[i]->gref); if (persistent_gnt) { @@ -819,7 +823,7 @@ again: pages[i]->page = persistent_gnt->page; pages[i]->persistent_gnt = persistent_gnt; } else { - if (get_free_page(blkif, &pages[i]->page)) + if (get_free_page(ring, &pages[i]->page)) goto out_of_memory; addr = vaddr(pages[i]->page); pages_to_gnt[segs_to_map] = pages[i]->page; @@ -852,7 +856,7 @@ again: BUG_ON(new_map_idx >= segs_to_map); if (unlikely(map[new_map_idx].status != 0)) { pr_debug("invalid buffer -- could not remap it\n"); - put_free_pages(blkif, &pages[seg_idx]->page, 1); + put_free_pages(ring, &pages[seg_idx]->page, 1); pages[seg_idx]->handle = BLKBACK_INVALID_HANDLE; ret |= 1; goto next; @@ -862,7 +866,7 @@ again: continue; } if (use_persistent_gnts && - blkif->persistent_gnt_c < xen_blkif_max_pgrants) { + ring->persistent_gnt_c < xen_blkif_max_pgrants) { /* * We are using persistent grants, the grant is * not mapped but we might have room for it. @@ -880,7 +884,7 @@ again: persistent_gnt->gnt = map[new_map_idx].ref; persistent_gnt->handle = map[new_map_idx].handle; persistent_gnt->page = pages[seg_idx]->page; - if (add_persistent_gnt(blkif, + if (add_persistent_gnt(ring, persistent_gnt)) { kfree(persistent_gnt); persistent_gnt = NULL; @@ -888,7 +892,7 @@ again: } pages[seg_idx]->persistent_gnt = persistent_gnt; pr_debug("grant %u added to the tree of persistent grants, using %u/%u\n", - persistent_gnt->gnt, blkif->persistent_gnt_c, + persistent_gnt->gnt, ring->persistent_gnt_c, xen_blkif_max_pgrants); goto next; } @@ -913,7 +917,7 @@ next: out_of_memory: pr_alert("%s: out of memory\n", __func__); - put_free_pages(blkif, pages_to_gnt, segs_to_map); + put_free_pages(ring, pages_to_gnt, segs_to_map); return -ENOMEM; } @@ -921,7 +925,7 @@ static int xen_blkbk_map_seg(struct pending_req *pending_req) { int rc; - rc = xen_blkbk_map(pending_req->blkif, pending_req->segments, + rc = xen_blkbk_map(pending_req->ring, pending_req->segments, pending_req->nr_segs, (pending_req->operation != BLKIF_OP_READ)); @@ -934,7 +938,7 @@ static int xen_blkbk_parse_indirect(struct blkif_request *req, struct phys_req *preq) { struct grant_page **pages = pending_req->indirect_pages; - struct xen_blkif *blkif = pending_req->blkif; + struct xen_blkif_ring *ring = pending_req->ring; int indirect_grefs, rc, n, nseg, i; struct blkif_request_segment *segments = NULL; @@ -945,7 +949,7 @@ static int xen_blkbk_parse_indirect(struct blkif_request *req, for (i = 0; i < indirect_grefs; i++) pages[i]->gref = req->u.indirect.indirect_grefs[i]; - rc = xen_blkbk_map(blkif, pages, indirect_grefs, true); + rc = xen_blkbk_map(ring, pages, indirect_grefs, true); if (rc) goto unmap; @@ -972,15 +976,16 @@ static int xen_blkbk_parse_indirect(struct blkif_request *req, unmap: if (segments) kunmap_atomic(segments); - xen_blkbk_unmap(blkif, pages, indirect_grefs); + xen_blkbk_unmap(ring, pages, indirect_grefs); return rc; } -static int dispatch_discard_io(struct xen_blkif *blkif, +static int dispatch_discard_io(struct xen_blkif_ring *ring, struct blkif_request *req) { int err = 0; int status = BLKIF_RSP_OKAY; + struct xen_blkif *blkif = ring->blkif; struct block_device *bdev = blkif->vbd.bdev; unsigned long secure; struct phys_req preq; @@ -997,7 +1002,7 @@ static int dispatch_discard_io(struct xen_blkif *blkif, preq.sector_number + preq.nr_sects, blkif->vbd.pdevice); goto fail_response; } - blkif->st_ds_req++; + ring->st_ds_req++; secure = (blkif->vbd.discard_secure && (req->u.discard.flag & BLKIF_DISCARD_SECURE)) ? @@ -1013,26 +1018,27 @@ fail_response: } else if (err) status = BLKIF_RSP_ERROR; - make_response(blkif, req->u.discard.id, req->operation, status); + make_response(ring, req->u.discard.id, req->operation, status); xen_blkif_put(blkif); return err; } -static int dispatch_other_io(struct xen_blkif *blkif, +static int dispatch_other_io(struct xen_blkif_ring *ring, struct blkif_request *req, struct pending_req *pending_req) { - free_req(blkif, pending_req); - make_response(blkif, req->u.other.id, req->operation, + free_req(ring, pending_req); + make_response(ring, req->u.other.id, req->operation, BLKIF_RSP_EOPNOTSUPP); return -EIO; } -static void xen_blk_drain_io(struct xen_blkif *blkif) +static void xen_blk_drain_io(struct xen_blkif_ring *ring) { + struct xen_blkif *blkif = ring->blkif; atomic_set(&blkif->drain, 1); do { - if (atomic_read(&blkif->inflight) == 0) + if (atomic_read(&ring->inflight) == 0) break; wait_for_completion_interruptible_timeout( &blkif->drain_complete, HZ); @@ -1053,12 +1059,12 @@ static void __end_block_io_op(struct pending_req *pending_req, int error) if ((pending_req->operation == BLKIF_OP_FLUSH_DISKCACHE) && (error == -EOPNOTSUPP)) { pr_debug("flush diskcache op failed, not supported\n"); - xen_blkbk_flush_diskcache(XBT_NIL, pending_req->blkif->be, 0); + xen_blkbk_flush_diskcache(XBT_NIL, pending_req->ring->blkif->be, 0); pending_req->status = BLKIF_RSP_EOPNOTSUPP; } else if ((pending_req->operation == BLKIF_OP_WRITE_BARRIER) && (error == -EOPNOTSUPP)) { pr_debug("write barrier op failed, not supported\n"); - xen_blkbk_barrier(XBT_NIL, pending_req->blkif->be, 0); + xen_blkbk_barrier(XBT_NIL, pending_req->ring->blkif->be, 0); pending_req->status = BLKIF_RSP_EOPNOTSUPP; } else if (error) { pr_debug("Buffer not up-to-date at end of operation," @@ -1092,9 +1098,9 @@ static void end_block_io_op(struct bio *bio, int error) * and transmute it to the block API to hand it over to the proper block disk. */ static int -__do_block_io_op(struct xen_blkif *blkif) +__do_block_io_op(struct xen_blkif_ring *ring) { - union blkif_back_rings *blk_rings = &blkif->blk_rings; + union blkif_back_rings *blk_rings = &ring->blk_rings; struct blkif_request req; struct pending_req *pending_req; RING_IDX rc, rp; @@ -1107,7 +1113,7 @@ __do_block_io_op(struct xen_blkif *blkif) if (RING_REQUEST_PROD_OVERFLOW(&blk_rings->common, rp)) { rc = blk_rings->common.rsp_prod_pvt; pr_warn("Frontend provided bogus ring requests (%d - %d = %d). Halting ring processing on dev=%04x\n", - rp, rc, rp - rc, blkif->vbd.pdevice); + rp, rc, rp - rc, ring->blkif->vbd.pdevice); return -EACCES; } while (rc != rp) { @@ -1120,14 +1126,14 @@ __do_block_io_op(struct xen_blkif *blkif) break; } - pending_req = alloc_req(blkif); + pending_req = alloc_req(ring); if (NULL == pending_req) { - blkif->st_oo_req++; + ring->st_oo_req++; more_to_do = 1; break; } - switch (blkif->blk_protocol) { + switch (ring->blkif->blk_protocol) { case BLKIF_PROTOCOL_NATIVE: memcpy(&req, RING_GET_REQUEST(&blk_rings->native, rc), sizeof(req)); break; @@ -1151,16 +1157,16 @@ __do_block_io_op(struct xen_blkif *blkif) case BLKIF_OP_WRITE_BARRIER: case BLKIF_OP_FLUSH_DISKCACHE: case BLKIF_OP_INDIRECT: - if (dispatch_rw_block_io(blkif, &req, pending_req)) + if (dispatch_rw_block_io(ring, &req, pending_req)) goto done; break; case BLKIF_OP_DISCARD: - free_req(blkif, pending_req); - if (dispatch_discard_io(blkif, &req)) + free_req(ring, pending_req); + if (dispatch_discard_io(ring, &req)) goto done; break; default: - if (dispatch_other_io(blkif, &req, pending_req)) + if (dispatch_other_io(ring, &req, pending_req)) goto done; break; } @@ -1173,13 +1179,13 @@ done: } static int -do_block_io_op(struct xen_blkif *blkif) +do_block_io_op(struct xen_blkif_ring *ring) { - union blkif_back_rings *blk_rings = &blkif->blk_rings; + union blkif_back_rings *blk_rings = &ring->blk_rings; int more_to_do; do { - more_to_do = __do_block_io_op(blkif); + more_to_do = __do_block_io_op(ring); if (more_to_do) break; @@ -1192,7 +1198,7 @@ do_block_io_op(struct xen_blkif *blkif) * Transmutation of the 'struct blkif_request' to a proper 'struct bio' * and call the 'submit_bio' to pass it to the underlying storage. */ -static int dispatch_rw_block_io(struct xen_blkif *blkif, +static int dispatch_rw_block_io(struct xen_blkif_ring *ring, struct blkif_request *req, struct pending_req *pending_req) { @@ -1219,17 +1225,17 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, switch (req_operation) { case BLKIF_OP_READ: - blkif->st_rd_req++; + ring->st_rd_req++; operation = READ; break; case BLKIF_OP_WRITE: - blkif->st_wr_req++; + ring->st_wr_req++; operation = WRITE_ODIRECT; break; case BLKIF_OP_WRITE_BARRIER: drain = true; case BLKIF_OP_FLUSH_DISKCACHE: - blkif->st_f_req++; + ring->st_f_req++; operation = WRITE_FLUSH; break; default: @@ -1254,7 +1260,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, preq.nr_sects = 0; - pending_req->blkif = blkif; + pending_req->ring = ring; pending_req->id = req->u.rw.id; pending_req->operation = req_operation; pending_req->status = BLKIF_RSP_OKAY; @@ -1281,12 +1287,12 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, goto fail_response; } - if (xen_vbd_translate(&preq, blkif, operation) != 0) { + if (xen_vbd_translate(&preq, ring->blkif, operation) != 0) { pr_debug("access denied: %s of [%llu,%llu] on dev=%04x\n", operation == READ ? "read" : "write", preq.sector_number, preq.sector_number + preq.nr_sects, - blkif->vbd.pdevice); + ring->blkif->vbd.pdevice); goto fail_response; } @@ -1298,7 +1304,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, if (((int)preq.sector_number|(int)seg[i].nsec) & ((bdev_logical_block_size(preq.bdev) >> 9) - 1)) { pr_debug("Misaligned I/O request from domain %d\n", - blkif->domid); + ring->blkif->domid); goto fail_response; } } @@ -1307,7 +1313,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, * issue the WRITE_FLUSH. */ if (drain) - xen_blk_drain_io(pending_req->blkif); + xen_blk_drain_io(pending_req->ring); /* * If we have failed at this point, we need to undo the M2P override, @@ -1322,8 +1328,8 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, * This corresponding xen_blkif_put is done in __end_block_io_op, or * below (in "!bio") if we are handling a BLKIF_OP_DISCARD. */ - xen_blkif_get(blkif); - atomic_inc(&blkif->inflight); + xen_blkif_get(ring->blkif); + atomic_inc(&ring->inflight); for (i = 0; i < nseg; i++) { while ((bio == NULL) || @@ -1371,19 +1377,19 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, blk_finish_plug(&plug); if (operation == READ) - blkif->st_rd_sect += preq.nr_sects; + ring->st_rd_sect += preq.nr_sects; else if (operation & WRITE) - blkif->st_wr_sect += preq.nr_sects; + ring->st_wr_sect += preq.nr_sects; return 0; fail_flush: - xen_blkbk_unmap(blkif, pending_req->segments, + xen_blkbk_unmap(ring, pending_req->segments, pending_req->nr_segs); fail_response: /* Haven't submitted any bio's yet. */ - make_response(blkif, req->u.rw.id, req_operation, BLKIF_RSP_ERROR); - free_req(blkif, pending_req); + make_response(ring, req->u.rw.id, req_operation, BLKIF_RSP_ERROR); + free_req(ring, pending_req); msleep(1); /* back off a bit */ return -EIO; @@ -1401,21 +1407,22 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, /* * Put a response on the ring on how the operation fared. */ -static void make_response(struct xen_blkif *blkif, u64 id, +static void make_response(struct xen_blkif_ring *ring, u64 id, unsigned short op, int st) { struct blkif_response resp; unsigned long flags; - union blkif_back_rings *blk_rings = &blkif->blk_rings; + union blkif_back_rings *blk_rings; int notify; resp.id = id; resp.operation = op; resp.status = st; - spin_lock_irqsave(&blkif->blk_ring_lock, flags); + spin_lock_irqsave(&ring->blk_ring_lock, flags); + blk_rings = &ring->blk_rings; /* Place on the response ring for the relevant domain. */ - switch (blkif->blk_protocol) { + switch (ring->blkif->blk_protocol) { case BLKIF_PROTOCOL_NATIVE: memcpy(RING_GET_RESPONSE(&blk_rings->native, blk_rings->native.rsp_prod_pvt), &resp, sizeof(resp)); @@ -1433,9 +1440,9 @@ static void make_response(struct xen_blkif *blkif, u64 id, } blk_rings->common.rsp_prod_pvt++; RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&blk_rings->common, notify); - spin_unlock_irqrestore(&blkif->blk_ring_lock, flags); + spin_unlock_irqrestore(&ring->blk_ring_lock, flags); if (notify) - notify_remote_via_irq(blkif->irq); + notify_remote_via_irq(ring->irq); } static int __init xen_blkif_init(void) diff --git a/drivers/block/xen-blkback/common.h b/drivers/block/xen-blkback/common.h index 45a044a..cc253d4 100644 --- a/drivers/block/xen-blkback/common.h +++ b/drivers/block/xen-blkback/common.h @@ -260,30 +260,18 @@ struct persistent_gnt { struct list_head remove_node; }; -struct xen_blkif { - /* Unique identifier for this interface. */ - domid_t domid; - unsigned int handle; +/* Per-ring information */ +struct xen_blkif_ring { /* Physical parameters of the comms window. */ unsigned int irq; - /* Comms information. */ - enum blkif_protocol blk_protocol; union blkif_back_rings blk_rings; void *blk_ring; - /* The VBD attached to this interface. */ - struct xen_vbd vbd; - /* Back pointer to the backend_info. */ - struct backend_info *be; /* Private fields. */ spinlock_t blk_ring_lock; - atomic_t refcnt; wait_queue_head_t wq; - /* for barrier (drain) requests */ - struct completion drain_complete; - atomic_t drain; atomic_t inflight; - /* One thread per one blkif. */ + /* One thread per blkif ring. */ struct task_struct *xenblkd; unsigned int waiting_reqs; @@ -321,7 +309,37 @@ struct xen_blkif { struct work_struct free_work; /* Thread shutdown wait queue. */ wait_queue_head_t shutdown_wq; + struct xen_blkif *blkif; +}; + +struct xen_blkif { + /* Unique identifier for this interface. */ + domid_t domid; + unsigned int handle; + /* Comms information. */ + enum blkif_protocol blk_protocol; + /* The VBD attached to this interface. */ + struct xen_vbd vbd; + /* Back pointer to the backend_info. */ + struct backend_info *be; + /* for barrier (drain) requests */ + struct completion drain_complete; + atomic_t drain; + atomic_t refcnt; + struct work_struct free_work; + + /* statistics */ + unsigned long st_print; + 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; unsigned int nr_ring_pages; + /* All rings for this device */ + struct xen_blkif_ring ring; }; struct seg_buf { @@ -343,7 +361,7 @@ struct grant_page { * response queued for it, with the saved 'id' passed back. */ struct pending_req { - struct xen_blkif *blkif; + struct xen_blkif_ring *ring; u64 id; int nr_segs; atomic_t pendcnt; @@ -385,7 +403,7 @@ int xen_blkif_xenbus_init(void); irqreturn_t xen_blkif_be_int(int irq, void *dev_id); int xen_blkif_schedule(void *arg); int xen_blkif_purge_persistent(void *arg); -void xen_blkbk_free_caches(struct xen_blkif *blkif); +void xen_blkbk_free_caches(struct xen_blkif_ring *ring); int xen_blkbk_flush_diskcache(struct xenbus_transaction xbt, struct backend_info *be, int state); diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c index deb3f00..6482ee3 100644 --- a/drivers/block/xen-blkback/xenbus.c +++ b/drivers/block/xen-blkback/xenbus.c @@ -88,7 +88,7 @@ static void xen_update_blkif_status(struct xen_blkif *blkif) char name[BLKBACK_NAME_LEN]; /* Not ready to connect? */ - if (!blkif->irq || !blkif->vbd.bdev) + if (!blkif->ring.irq || !blkif->vbd.bdev) return; /* Already connected? */ @@ -113,10 +113,10 @@ static void xen_update_blkif_status(struct xen_blkif *blkif) } invalidate_inode_pages2(blkif->vbd.bdev->bd_inode->i_mapping); - blkif->xenblkd = kthread_run(xen_blkif_schedule, blkif, "%s", name); - if (IS_ERR(blkif->xenblkd)) { - err = PTR_ERR(blkif->xenblkd); - blkif->xenblkd = NULL; + blkif->ring.xenblkd = kthread_run(xen_blkif_schedule, &blkif->ring, "%s", name); + if (IS_ERR(blkif->ring.xenblkd)) { + err = PTR_ERR(blkif->ring.xenblkd); + blkif->ring.xenblkd = NULL; xenbus_dev_error(blkif->be->dev, err, "start xenblkd"); return; } @@ -125,6 +125,7 @@ static void xen_update_blkif_status(struct xen_blkif *blkif) static struct xen_blkif *xen_blkif_alloc(domid_t domid) { struct xen_blkif *blkif; + struct xen_blkif_ring *ring; BUILD_BUG_ON(MAX_INDIRECT_PAGES > BLKIF_MAX_INDIRECT_PAGES_PER_REQUEST); @@ -133,41 +134,44 @@ static struct xen_blkif *xen_blkif_alloc(domid_t domid) return ERR_PTR(-ENOMEM); blkif->domid = domid; - spin_lock_init(&blkif->blk_ring_lock); + ring = &blkif->ring; + ring->blkif = blkif; + spin_lock_init(&ring->blk_ring_lock); atomic_set(&blkif->refcnt, 1); - init_waitqueue_head(&blkif->wq); + init_waitqueue_head(&ring->wq); init_completion(&blkif->drain_complete); atomic_set(&blkif->drain, 0); - blkif->st_print = jiffies; - blkif->persistent_gnts.rb_node = NULL; - spin_lock_init(&blkif->free_pages_lock); - INIT_LIST_HEAD(&blkif->free_pages); - INIT_LIST_HEAD(&blkif->persistent_purge_list); - blkif->free_pages_num = 0; - atomic_set(&blkif->persistent_gnt_in_use, 0); - atomic_set(&blkif->inflight, 0); - INIT_WORK(&blkif->persistent_purge_work, xen_blkbk_unmap_purged_grants); - - INIT_LIST_HEAD(&blkif->pending_free); + ring->st_print = jiffies; + ring->persistent_gnts.rb_node = NULL; + spin_lock_init(&ring->free_pages_lock); + INIT_LIST_HEAD(&ring->free_pages); + INIT_LIST_HEAD(&ring->persistent_purge_list); + ring->free_pages_num = 0; + atomic_set(&ring->persistent_gnt_in_use, 0); + atomic_set(&ring->inflight, 0); + INIT_WORK(&ring->persistent_purge_work, xen_blkbk_unmap_purged_grants); + + INIT_LIST_HEAD(&ring->pending_free); INIT_WORK(&blkif->free_work, xen_blkif_deferred_free); - spin_lock_init(&blkif->pending_free_lock); - init_waitqueue_head(&blkif->pending_free_wq); - init_waitqueue_head(&blkif->shutdown_wq); + spin_lock_init(&ring->pending_free_lock); + init_waitqueue_head(&ring->pending_free_wq); + init_waitqueue_head(&ring->shutdown_wq); return blkif; } -static int xen_blkif_map(struct xen_blkif *blkif, grant_ref_t *gref, +static int xen_blkif_map(struct xen_blkif_ring *ring, grant_ref_t *gref, unsigned int nr_grefs, unsigned int evtchn) { int err; + struct xen_blkif *blkif = ring->blkif; /* Already connected through? */ - if (blkif->irq) + if (ring->irq) return 0; err = xenbus_map_ring_valloc(blkif->be->dev, gref, nr_grefs, - &blkif->blk_ring); + &ring->blk_ring); if (err < 0) return err; @@ -175,22 +179,22 @@ static int xen_blkif_map(struct xen_blkif *blkif, grant_ref_t *gref, case BLKIF_PROTOCOL_NATIVE: { struct blkif_sring *sring; - sring = (struct blkif_sring *)blkif->blk_ring; - BACK_RING_INIT(&blkif->blk_rings.native, sring, PAGE_SIZE * nr_grefs); + sring = (struct blkif_sring *)ring->blk_ring; + BACK_RING_INIT(&ring->blk_rings.native, sring, PAGE_SIZE * nr_grefs); break; } case BLKIF_PROTOCOL_X86_32: { struct blkif_x86_32_sring *sring_x86_32; - sring_x86_32 = (struct blkif_x86_32_sring *)blkif->blk_ring; - BACK_RING_INIT(&blkif->blk_rings.x86_32, sring_x86_32, PAGE_SIZE * nr_grefs); + sring_x86_32 = (struct blkif_x86_32_sring *)ring->blk_ring; + BACK_RING_INIT(&ring->blk_rings.x86_32, sring_x86_32, PAGE_SIZE * nr_grefs); break; } case BLKIF_PROTOCOL_X86_64: { struct blkif_x86_64_sring *sring_x86_64; - sring_x86_64 = (struct blkif_x86_64_sring *)blkif->blk_ring; - BACK_RING_INIT(&blkif->blk_rings.x86_64, sring_x86_64, PAGE_SIZE * nr_grefs); + sring_x86_64 = (struct blkif_x86_64_sring *)ring->blk_ring; + BACK_RING_INIT(&ring->blk_rings.x86_64, sring_x86_64, PAGE_SIZE * nr_grefs); break; } default: @@ -199,44 +203,46 @@ static int xen_blkif_map(struct xen_blkif *blkif, grant_ref_t *gref, err = bind_interdomain_evtchn_to_irqhandler(blkif->domid, evtchn, xen_blkif_be_int, 0, - "blkif-backend", blkif); + "blkif-backend", ring); if (err < 0) { - xenbus_unmap_ring_vfree(blkif->be->dev, blkif->blk_ring); - blkif->blk_rings.common.sring = NULL; + xenbus_unmap_ring_vfree(blkif->be->dev, ring->blk_ring); + ring->blk_rings.common.sring = NULL; return err; } - blkif->irq = err; + ring->irq = err; return 0; } static int xen_blkif_disconnect(struct xen_blkif *blkif) { - if (blkif->xenblkd) { - kthread_stop(blkif->xenblkd); - wake_up(&blkif->shutdown_wq); - blkif->xenblkd = NULL; + struct xen_blkif_ring *ring = &blkif->ring; + + if (ring->xenblkd) { + kthread_stop(ring->xenblkd); + wake_up(&ring->shutdown_wq); + ring->xenblkd = NULL; } /* The above kthread_stop() guarantees that at this point we * don't have any discard_io or other_io requests. So, checking * for inflight IO is enough. */ - if (atomic_read(&blkif->inflight) > 0) + if (atomic_read(&ring->inflight) > 0) return -EBUSY; - if (blkif->irq) { - unbind_from_irqhandler(blkif->irq, blkif); - blkif->irq = 0; + if (ring->irq) { + unbind_from_irqhandler(ring->irq, ring); + ring->irq = 0; } - if (blkif->blk_rings.common.sring) { - xenbus_unmap_ring_vfree(blkif->be->dev, blkif->blk_ring); - blkif->blk_rings.common.sring = NULL; + if (ring->blk_rings.common.sring) { + xenbus_unmap_ring_vfree(blkif->be->dev, ring->blk_ring); + ring->blk_rings.common.sring = NULL; } /* Remove all persistent grants and the cache of ballooned pages. */ - xen_blkbk_free_caches(blkif); + xen_blkbk_free_caches(ring); return 0; } @@ -245,20 +251,21 @@ static void xen_blkif_free(struct xen_blkif *blkif) { struct pending_req *req, *n; int i = 0, j; + struct xen_blkif_ring *ring = &blkif->ring; xen_blkif_disconnect(blkif); xen_vbd_free(&blkif->vbd); /* Make sure everything is drained before shutting down */ - BUG_ON(blkif->persistent_gnt_c != 0); - BUG_ON(atomic_read(&blkif->persistent_gnt_in_use) != 0); - BUG_ON(blkif->free_pages_num != 0); - BUG_ON(!list_empty(&blkif->persistent_purge_list)); - BUG_ON(!list_empty(&blkif->free_pages)); - BUG_ON(!RB_EMPTY_ROOT(&blkif->persistent_gnts)); + BUG_ON(ring->persistent_gnt_c != 0); + BUG_ON(atomic_read(&ring->persistent_gnt_in_use) != 0); + BUG_ON(ring->free_pages_num != 0); + BUG_ON(!list_empty(&ring->persistent_purge_list)); + BUG_ON(!list_empty(&ring->free_pages)); + BUG_ON(!RB_EMPTY_ROOT(&ring->persistent_gnts)); /* Check that there is no request in use */ - list_for_each_entry_safe(req, n, &blkif->pending_free, free_list) { + list_for_each_entry_safe(req, n, &ring->pending_free, free_list) { list_del(&req->free_list); for (j = 0; j < MAX_INDIRECT_SEGMENTS; j++) @@ -298,6 +305,16 @@ int __init xen_blkif_interface_init(void) { \ struct xenbus_device *dev = to_xenbus_device(_dev); \ struct backend_info *be = dev_get_drvdata(&dev->dev); \ + struct xen_blkif *blkif = be->blkif; \ + struct xen_blkif_ring *ring = &blkif->ring; \ + \ + blkif->st_oo_req = ring->st_oo_req; \ + blkif->st_rd_req = ring->st_rd_req; \ + blkif->st_wr_req = ring->st_wr_req; \ + blkif->st_f_req = ring->st_f_req; \ + blkif->st_ds_req = ring->st_ds_req; \ + blkif->st_rd_sect = ring->st_rd_sect; \ + blkif->st_wr_sect = ring->st_wr_sect; \ \ return sprintf(buf, format, ##args); \ } \ @@ -830,6 +847,7 @@ static int connect_ring(struct backend_info *be) char protocol[64] = ""; struct pending_req *req, *n; int err, i, j; + struct xen_blkif_ring *ring = &be->blkif->ring; pr_debug("%s %s\n", __func__, dev->otherend); @@ -918,7 +936,7 @@ static int connect_ring(struct backend_info *be) req = kzalloc(sizeof(*req), GFP_KERNEL); if (!req) goto fail; - list_add_tail(&req->free_list, &be->blkif->pending_free); + list_add_tail(&req->free_list, &ring->pending_free); for (j = 0; j < MAX_INDIRECT_SEGMENTS; j++) { req->segments[j] = kzalloc(sizeof(*req->segments[0]), GFP_KERNEL); if (!req->segments[j]) @@ -933,7 +951,7 @@ static int connect_ring(struct backend_info *be) } /* Map the shared frame, irq etc. */ - err = xen_blkif_map(be->blkif, ring_ref, nr_grefs, evtchn); + err = xen_blkif_map(ring, ring_ref, nr_grefs, evtchn); if (err) { xenbus_dev_fatal(dev, err, "mapping ring-ref port %u", evtchn); return err; @@ -942,7 +960,7 @@ static int connect_ring(struct backend_info *be) return 0; fail: - list_for_each_entry_safe(req, n, &be->blkif->pending_free, free_list) { + list_for_each_entry_safe(req, n, &ring->pending_free, free_list) { list_del(&req->free_list); for (j = 0; j < MAX_INDIRECT_SEGMENTS; j++) { if (!req->segments[j]) -- 1.7.10.4 From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bob Liu Subject: [PATCH v3 7/9] xen/blkback: separate ring information out of struct xen_blkif Date: Sat, 5 Sep 2015 20:39:40 +0800 Message-ID: <1441456782-31318-8-git-send-email-bob.liu@oracle.com> References: <1441456782-31318-1-git-send-email-bob.liu@oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1441456782-31318-1-git-send-email-bob.liu@oracle.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: xen-devel@lists.xen.org Cc: hch@infradead.org, felipe.franciosi@citrix.com, rafal.mielniczuk@citrix.com, linux-kernel@vger.kernel.org, jonathan.davies@citrix.com, axboe@fb.com, Bob Liu , david.vrabel@citrix.com, avanzini.arianna@gmail.com, boris.ostrovsky@oracle.com, roger.pau@citrix.com List-Id: xen-devel@lists.xenproject.org Split per ring information to an new structure:xen_blkif_ring, so that one vbd device can associate with one or more rings/hardware queues. This patch is a preparation for supporting multi hardware queues/rings. Signed-off-by: Arianna Avanzini Signed-off-by: Bob Liu --- drivers/block/xen-blkback/blkback.c | 365 ++++++++++++++++++----------------- drivers/block/xen-blkback/common.h | 52 +++-- drivers/block/xen-blkback/xenbus.c | 130 +++++++------ 3 files changed, 295 insertions(+), 252 deletions(-) diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c index 954c002..fd02240 100644 --- a/drivers/block/xen-blkback/blkback.c +++ b/drivers/block/xen-blkback/blkback.c @@ -113,71 +113,71 @@ module_param(log_stats, int, 0644); /* Number of free pages to remove on each call to gnttab_free_pages */ #define NUM_BATCH_FREE_PAGES 10 -static inline int get_free_page(struct xen_blkif *blkif, struct page **page) +static inline int get_free_page(struct xen_blkif_ring *ring, struct page **page) { unsigned long flags; - spin_lock_irqsave(&blkif->free_pages_lock, flags); - if (list_empty(&blkif->free_pages)) { - BUG_ON(blkif->free_pages_num != 0); - spin_unlock_irqrestore(&blkif->free_pages_lock, flags); + spin_lock_irqsave(&ring->free_pages_lock, flags); + if (list_empty(&ring->free_pages)) { + BUG_ON(ring->free_pages_num != 0); + spin_unlock_irqrestore(&ring->free_pages_lock, flags); return gnttab_alloc_pages(1, page); } - BUG_ON(blkif->free_pages_num == 0); - page[0] = list_first_entry(&blkif->free_pages, struct page, lru); + BUG_ON(ring->free_pages_num == 0); + page[0] = list_first_entry(&ring->free_pages, struct page, lru); list_del(&page[0]->lru); - blkif->free_pages_num--; - spin_unlock_irqrestore(&blkif->free_pages_lock, flags); + ring->free_pages_num--; + spin_unlock_irqrestore(&ring->free_pages_lock, flags); return 0; } -static inline void put_free_pages(struct xen_blkif *blkif, struct page **page, +static inline void put_free_pages(struct xen_blkif_ring *ring, struct page **page, int num) { unsigned long flags; int i; - spin_lock_irqsave(&blkif->free_pages_lock, flags); + spin_lock_irqsave(&ring->free_pages_lock, flags); for (i = 0; i < num; i++) - list_add(&page[i]->lru, &blkif->free_pages); - blkif->free_pages_num += num; - spin_unlock_irqrestore(&blkif->free_pages_lock, flags); + list_add(&page[i]->lru, &ring->free_pages); + ring->free_pages_num += num; + spin_unlock_irqrestore(&ring->free_pages_lock, flags); } -static inline void shrink_free_pagepool(struct xen_blkif *blkif, int num) +static inline void shrink_free_pagepool(struct xen_blkif_ring *ring, int num) { /* Remove requested pages in batches of NUM_BATCH_FREE_PAGES */ struct page *page[NUM_BATCH_FREE_PAGES]; unsigned int num_pages = 0; unsigned long flags; - spin_lock_irqsave(&blkif->free_pages_lock, flags); - while (blkif->free_pages_num > num) { - BUG_ON(list_empty(&blkif->free_pages)); - page[num_pages] = list_first_entry(&blkif->free_pages, + spin_lock_irqsave(&ring->free_pages_lock, flags); + while (ring->free_pages_num > num) { + BUG_ON(list_empty(&ring->free_pages)); + page[num_pages] = list_first_entry(&ring->free_pages, struct page, lru); list_del(&page[num_pages]->lru); - blkif->free_pages_num--; + ring->free_pages_num--; if (++num_pages == NUM_BATCH_FREE_PAGES) { - spin_unlock_irqrestore(&blkif->free_pages_lock, flags); + spin_unlock_irqrestore(&ring->free_pages_lock, flags); gnttab_free_pages(num_pages, page); - spin_lock_irqsave(&blkif->free_pages_lock, flags); + spin_lock_irqsave(&ring->free_pages_lock, flags); num_pages = 0; } } - spin_unlock_irqrestore(&blkif->free_pages_lock, flags); + spin_unlock_irqrestore(&ring->free_pages_lock, flags); if (num_pages != 0) gnttab_free_pages(num_pages, page); } #define vaddr(page) ((unsigned long)pfn_to_kaddr(page_to_pfn(page))) -static int do_block_io_op(struct xen_blkif *blkif); -static int dispatch_rw_block_io(struct xen_blkif *blkif, +static int do_block_io_op(struct xen_blkif_ring *ring); +static int dispatch_rw_block_io(struct xen_blkif_ring *ring, struct blkif_request *req, struct pending_req *pending_req); -static void make_response(struct xen_blkif *blkif, u64 id, +static void make_response(struct xen_blkif_ring *ring, u64 id, unsigned short op, int st); #define foreach_grant_safe(pos, n, rbtree, node) \ @@ -198,19 +198,19 @@ static void make_response(struct xen_blkif *blkif, u64 id, * bit operations to modify the flags of a persistent grant and to count * the number of used grants. */ -static int add_persistent_gnt(struct xen_blkif *blkif, +static int add_persistent_gnt(struct xen_blkif_ring *ring, struct persistent_gnt *persistent_gnt) { struct rb_node **new = NULL, *parent = NULL; struct persistent_gnt *this; - if (blkif->persistent_gnt_c >= xen_blkif_max_pgrants) { - if (!blkif->vbd.overflow_max_grants) - blkif->vbd.overflow_max_grants = 1; + if (ring->persistent_gnt_c >= xen_blkif_max_pgrants) { + if (!ring->blkif->vbd.overflow_max_grants) + ring->blkif->vbd.overflow_max_grants = 1; return -EBUSY; } /* Figure out where to put new node */ - new = &blkif->persistent_gnts.rb_node; + new = &ring->persistent_gnts.rb_node; while (*new) { this = container_of(*new, struct persistent_gnt, node); @@ -229,19 +229,19 @@ static int add_persistent_gnt(struct xen_blkif *blkif, set_bit(PERSISTENT_GNT_ACTIVE, persistent_gnt->flags); /* Add new node and rebalance tree. */ rb_link_node(&(persistent_gnt->node), parent, new); - rb_insert_color(&(persistent_gnt->node), &blkif->persistent_gnts); - blkif->persistent_gnt_c++; - atomic_inc(&blkif->persistent_gnt_in_use); + rb_insert_color(&(persistent_gnt->node), &ring->persistent_gnts); + ring->persistent_gnt_c++; + atomic_inc(&ring->persistent_gnt_in_use); return 0; } -static struct persistent_gnt *get_persistent_gnt(struct xen_blkif *blkif, - grant_ref_t gref) +static struct persistent_gnt *get_persistent_gnt(struct xen_blkif_ring *ring, + grant_ref_t gref) { struct persistent_gnt *data; struct rb_node *node = NULL; - node = blkif->persistent_gnts.rb_node; + node = ring->persistent_gnts.rb_node; while (node) { data = container_of(node, struct persistent_gnt, node); @@ -255,24 +255,24 @@ static struct persistent_gnt *get_persistent_gnt(struct xen_blkif *blkif, return NULL; } set_bit(PERSISTENT_GNT_ACTIVE, data->flags); - atomic_inc(&blkif->persistent_gnt_in_use); + atomic_inc(&ring->persistent_gnt_in_use); return data; } } return NULL; } -static void put_persistent_gnt(struct xen_blkif *blkif, +static void put_persistent_gnt(struct xen_blkif_ring *ring, struct persistent_gnt *persistent_gnt) { if(!test_bit(PERSISTENT_GNT_ACTIVE, persistent_gnt->flags)) pr_alert_ratelimited("freeing a grant already unused\n"); set_bit(PERSISTENT_GNT_WAS_ACTIVE, persistent_gnt->flags); clear_bit(PERSISTENT_GNT_ACTIVE, persistent_gnt->flags); - atomic_dec(&blkif->persistent_gnt_in_use); + atomic_dec(&ring->persistent_gnt_in_use); } -static void free_persistent_gnts(struct xen_blkif *blkif, struct rb_root *root, +static void free_persistent_gnts(struct xen_blkif_ring *ring, struct rb_root *root, unsigned int num) { struct gnttab_unmap_grant_ref unmap[BLKIF_MAX_SEGMENTS_PER_REQUEST]; @@ -303,7 +303,7 @@ static void free_persistent_gnts(struct xen_blkif *blkif, struct rb_root *root, unmap_data.count = segs_to_unmap; BUG_ON(gnttab_unmap_refs_sync(&unmap_data)); - put_free_pages(blkif, pages, segs_to_unmap); + put_free_pages(ring, pages, segs_to_unmap); segs_to_unmap = 0; } @@ -320,15 +320,15 @@ void xen_blkbk_unmap_purged_grants(struct work_struct *work) struct page *pages[BLKIF_MAX_SEGMENTS_PER_REQUEST]; struct persistent_gnt *persistent_gnt; int segs_to_unmap = 0; - struct xen_blkif *blkif = container_of(work, typeof(*blkif), persistent_purge_work); + struct xen_blkif_ring *ring = container_of(work, typeof(*ring), persistent_purge_work); struct gntab_unmap_queue_data unmap_data; unmap_data.pages = pages; unmap_data.unmap_ops = unmap; unmap_data.kunmap_ops = NULL; - while(!list_empty(&blkif->persistent_purge_list)) { - persistent_gnt = list_first_entry(&blkif->persistent_purge_list, + while(!list_empty(&ring->persistent_purge_list)) { + persistent_gnt = list_first_entry(&ring->persistent_purge_list, struct persistent_gnt, remove_node); list_del(&persistent_gnt->remove_node); @@ -343,7 +343,7 @@ void xen_blkbk_unmap_purged_grants(struct work_struct *work) if (++segs_to_unmap == BLKIF_MAX_SEGMENTS_PER_REQUEST) { unmap_data.count = segs_to_unmap; BUG_ON(gnttab_unmap_refs_sync(&unmap_data)); - put_free_pages(blkif, pages, segs_to_unmap); + put_free_pages(ring, pages, segs_to_unmap); segs_to_unmap = 0; } kfree(persistent_gnt); @@ -351,34 +351,35 @@ void xen_blkbk_unmap_purged_grants(struct work_struct *work) if (segs_to_unmap > 0) { unmap_data.count = segs_to_unmap; BUG_ON(gnttab_unmap_refs_sync(&unmap_data)); - put_free_pages(blkif, pages, segs_to_unmap); + put_free_pages(ring, pages, segs_to_unmap); } } -static void purge_persistent_gnt(struct xen_blkif *blkif) +static void purge_persistent_gnt(struct xen_blkif_ring *ring) { struct persistent_gnt *persistent_gnt; struct rb_node *n; unsigned int num_clean, total; bool scan_used = false, clean_used = false; struct rb_root *root; + struct xen_blkif *blkif = ring->blkif; - if (blkif->persistent_gnt_c < xen_blkif_max_pgrants || - (blkif->persistent_gnt_c == xen_blkif_max_pgrants && + if (ring->persistent_gnt_c < xen_blkif_max_pgrants || + (ring->persistent_gnt_c == xen_blkif_max_pgrants && !blkif->vbd.overflow_max_grants)) { return; } - if (work_busy(&blkif->persistent_purge_work)) { + if (work_busy(&ring->persistent_purge_work)) { pr_alert_ratelimited("Scheduled work from previous purge is still busy, cannot purge list\n"); return; } num_clean = (xen_blkif_max_pgrants / 100) * LRU_PERCENT_CLEAN; - num_clean = blkif->persistent_gnt_c - xen_blkif_max_pgrants + num_clean; - num_clean = min(blkif->persistent_gnt_c, num_clean); + num_clean = ring->persistent_gnt_c - xen_blkif_max_pgrants + num_clean; + num_clean = min(ring->persistent_gnt_c, num_clean); if ((num_clean == 0) || - (num_clean > (blkif->persistent_gnt_c - atomic_read(&blkif->persistent_gnt_in_use)))) + (num_clean > (ring->persistent_gnt_c - atomic_read(&ring->persistent_gnt_in_use)))) return; /* @@ -394,8 +395,8 @@ static void purge_persistent_gnt(struct xen_blkif *blkif) pr_debug("Going to purge %u persistent grants\n", num_clean); - BUG_ON(!list_empty(&blkif->persistent_purge_list)); - root = &blkif->persistent_gnts; + BUG_ON(!list_empty(&ring->persistent_purge_list)); + root = &ring->persistent_gnts; purge_list: foreach_grant_safe(persistent_gnt, n, root, node) { BUG_ON(persistent_gnt->handle == @@ -414,7 +415,7 @@ purge_list: rb_erase(&persistent_gnt->node, root); list_add(&persistent_gnt->remove_node, - &blkif->persistent_purge_list); + &ring->persistent_purge_list); if (--num_clean == 0) goto finished; } @@ -435,11 +436,11 @@ finished: goto purge_list; } - blkif->persistent_gnt_c -= (total - num_clean); + ring->persistent_gnt_c -= (total - num_clean); blkif->vbd.overflow_max_grants = 0; /* We can defer this work */ - schedule_work(&blkif->persistent_purge_work); + schedule_work(&ring->persistent_purge_work); pr_debug("Purged %u/%u\n", (total - num_clean), total); return; } @@ -447,18 +448,18 @@ finished: /* * Retrieve from the 'pending_reqs' a free pending_req structure to be used. */ -static struct pending_req *alloc_req(struct xen_blkif *blkif) +static struct pending_req *alloc_req(struct xen_blkif_ring *ring) { struct pending_req *req = NULL; unsigned long flags; - spin_lock_irqsave(&blkif->pending_free_lock, flags); - if (!list_empty(&blkif->pending_free)) { - req = list_entry(blkif->pending_free.next, struct pending_req, + spin_lock_irqsave(&ring->pending_free_lock, flags); + if (!list_empty(&ring->pending_free)) { + req = list_entry(ring->pending_free.next, struct pending_req, free_list); list_del(&req->free_list); } - spin_unlock_irqrestore(&blkif->pending_free_lock, flags); + spin_unlock_irqrestore(&ring->pending_free_lock, flags); return req; } @@ -466,17 +467,17 @@ static struct pending_req *alloc_req(struct xen_blkif *blkif) * Return the 'pending_req' structure back to the freepool. We also * wake up the thread if it was waiting for a free page. */ -static void free_req(struct xen_blkif *blkif, struct pending_req *req) +static void free_req(struct xen_blkif_ring *ring, struct pending_req *req) { unsigned long flags; int was_empty; - spin_lock_irqsave(&blkif->pending_free_lock, flags); - was_empty = list_empty(&blkif->pending_free); - list_add(&req->free_list, &blkif->pending_free); - spin_unlock_irqrestore(&blkif->pending_free_lock, flags); + spin_lock_irqsave(&ring->pending_free_lock, flags); + was_empty = list_empty(&ring->pending_free); + list_add(&req->free_list, &ring->pending_free); + spin_unlock_irqrestore(&ring->pending_free_lock, flags); if (was_empty) - wake_up(&blkif->pending_free_wq); + wake_up(&ring->pending_free_wq); } /* @@ -556,10 +557,10 @@ abort: /* * Notification from the guest OS. */ -static void blkif_notify_work(struct xen_blkif *blkif) +static void blkif_notify_work(struct xen_blkif_ring *ring) { - blkif->waiting_reqs = 1; - wake_up(&blkif->wq); + ring->waiting_reqs = 1; + wake_up(&ring->wq); } irqreturn_t xen_blkif_be_int(int irq, void *dev_id) @@ -572,25 +573,26 @@ irqreturn_t xen_blkif_be_int(int irq, void *dev_id) * SCHEDULER FUNCTIONS */ -static void print_stats(struct xen_blkif *blkif) +static void print_stats(struct xen_blkif_ring *ring) { pr_info("(%s): oo %3llu | rd %4llu | wr %4llu | f %4llu" " | ds %4llu | pg: %4u/%4d\n", - current->comm, blkif->st_oo_req, - blkif->st_rd_req, blkif->st_wr_req, - blkif->st_f_req, blkif->st_ds_req, - blkif->persistent_gnt_c, + current->comm, ring->st_oo_req, + ring->st_rd_req, ring->st_wr_req, + ring->st_f_req, ring->st_ds_req, + ring->persistent_gnt_c, xen_blkif_max_pgrants); - blkif->st_print = jiffies + msecs_to_jiffies(10 * 1000); - blkif->st_rd_req = 0; - blkif->st_wr_req = 0; - blkif->st_oo_req = 0; - blkif->st_ds_req = 0; + ring->st_print = jiffies + msecs_to_jiffies(10 * 1000); + ring->st_rd_req = 0; + ring->st_wr_req = 0; + ring->st_oo_req = 0; + ring->st_ds_req = 0; } int xen_blkif_schedule(void *arg) { - struct xen_blkif *blkif = arg; + struct xen_blkif_ring *ring = arg; + struct xen_blkif *blkif = ring->blkif; struct xen_vbd *vbd = &blkif->vbd; unsigned long timeout; int ret; @@ -606,50 +608,50 @@ int xen_blkif_schedule(void *arg) timeout = msecs_to_jiffies(LRU_INTERVAL); timeout = wait_event_interruptible_timeout( - blkif->wq, - blkif->waiting_reqs || kthread_should_stop(), + ring->wq, + ring->waiting_reqs || kthread_should_stop(), timeout); if (timeout == 0) goto purge_gnt_list; timeout = wait_event_interruptible_timeout( - blkif->pending_free_wq, - !list_empty(&blkif->pending_free) || + ring->pending_free_wq, + !list_empty(&ring->pending_free) || kthread_should_stop(), timeout); if (timeout == 0) goto purge_gnt_list; - blkif->waiting_reqs = 0; + ring->waiting_reqs = 0; smp_mb(); /* clear flag *before* checking for work */ - ret = do_block_io_op(blkif); + ret = do_block_io_op(ring); if (ret > 0) - blkif->waiting_reqs = 1; + ring->waiting_reqs = 1; if (ret == -EACCES) - wait_event_interruptible(blkif->shutdown_wq, + wait_event_interruptible(ring->shutdown_wq, kthread_should_stop()); purge_gnt_list: if (blkif->vbd.feature_gnt_persistent && - time_after(jiffies, blkif->next_lru)) { - purge_persistent_gnt(blkif); - blkif->next_lru = jiffies + msecs_to_jiffies(LRU_INTERVAL); + time_after(jiffies, ring->next_lru)) { + purge_persistent_gnt(ring); + ring->next_lru = jiffies + msecs_to_jiffies(LRU_INTERVAL); } /* Shrink if we have more than xen_blkif_max_buffer_pages */ - shrink_free_pagepool(blkif, xen_blkif_max_buffer_pages); + shrink_free_pagepool(ring, xen_blkif_max_buffer_pages); - if (log_stats && time_after(jiffies, blkif->st_print)) - print_stats(blkif); + if (log_stats && time_after(jiffies, ring->st_print)) + print_stats(ring); } /* Drain pending purge work */ - flush_work(&blkif->persistent_purge_work); + flush_work(&ring->persistent_purge_work); if (log_stats) - print_stats(blkif); + print_stats(ring); - blkif->xenblkd = NULL; + ring->xenblkd = NULL; xen_blkif_put(blkif); return 0; @@ -658,22 +660,22 @@ purge_gnt_list: /* * Remove persistent grants and empty the pool of free pages */ -void xen_blkbk_free_caches(struct xen_blkif *blkif) +void xen_blkbk_free_caches(struct xen_blkif_ring *ring) { /* Free all persistent grant pages */ - if (!RB_EMPTY_ROOT(&blkif->persistent_gnts)) - free_persistent_gnts(blkif, &blkif->persistent_gnts, - blkif->persistent_gnt_c); + if (!RB_EMPTY_ROOT(&ring->persistent_gnts)) + free_persistent_gnts(ring, &ring->persistent_gnts, + ring->persistent_gnt_c); - BUG_ON(!RB_EMPTY_ROOT(&blkif->persistent_gnts)); - blkif->persistent_gnt_c = 0; + BUG_ON(!RB_EMPTY_ROOT(&ring->persistent_gnts)); + ring->persistent_gnt_c = 0; /* Since we are shutting down remove all pages from the buffer */ - shrink_free_pagepool(blkif, 0 /* All */); + shrink_free_pagepool(ring, 0 /* All */); } static unsigned int xen_blkbk_unmap_prepare( - struct xen_blkif *blkif, + struct xen_blkif_ring *ring, struct grant_page **pages, unsigned int num, struct gnttab_unmap_grant_ref *unmap_ops, @@ -683,7 +685,7 @@ static unsigned int xen_blkbk_unmap_prepare( for (i = 0; i < num; i++) { if (pages[i]->persistent_gnt != NULL) { - put_persistent_gnt(blkif, pages[i]->persistent_gnt); + put_persistent_gnt(ring, pages[i]->persistent_gnt); continue; } if (pages[i]->handle == BLKBACK_INVALID_HANDLE) @@ -700,17 +702,18 @@ static unsigned int xen_blkbk_unmap_prepare( static void xen_blkbk_unmap_and_respond_callback(int result, struct gntab_unmap_queue_data *data) { - struct pending_req* pending_req = (struct pending_req*) (data->data); - struct xen_blkif *blkif = pending_req->blkif; + struct pending_req *pending_req = (struct pending_req *)(data->data); + struct xen_blkif_ring *ring = pending_req->ring; + struct xen_blkif *blkif = ring->blkif; /* BUG_ON used to reproduce existing behaviour, but is this the best way to deal with this? */ BUG_ON(result); - put_free_pages(blkif, data->pages, data->count); - make_response(blkif, pending_req->id, + put_free_pages(ring, data->pages, data->count); + make_response(ring, pending_req->id, pending_req->operation, pending_req->status); - free_req(blkif, pending_req); + free_req(ring, pending_req); /* * Make sure the request is freed before releasing blkif, * or there could be a race between free_req and the @@ -723,7 +726,7 @@ static void xen_blkbk_unmap_and_respond_callback(int result, struct gntab_unmap_ * pending_free_wq if there's a drain going on, but it has * to be taken into account if the current model is changed. */ - if (atomic_dec_and_test(&blkif->inflight) && atomic_read(&blkif->drain)) { + if (atomic_dec_and_test(&ring->inflight) && atomic_read(&blkif->drain)) { complete(&blkif->drain_complete); } xen_blkif_put(blkif); @@ -732,11 +735,11 @@ static void xen_blkbk_unmap_and_respond_callback(int result, struct gntab_unmap_ static void xen_blkbk_unmap_and_respond(struct pending_req *req) { struct gntab_unmap_queue_data* work = &req->gnttab_unmap_data; - struct xen_blkif *blkif = req->blkif; + struct xen_blkif_ring *ring = req->ring; struct grant_page **pages = req->segments; unsigned int invcount; - invcount = xen_blkbk_unmap_prepare(blkif, pages, req->nr_segs, + invcount = xen_blkbk_unmap_prepare(ring, pages, req->nr_segs, req->unmap, req->unmap_pages); work->data = req; @@ -757,7 +760,7 @@ static void xen_blkbk_unmap_and_respond(struct pending_req *req) * of hypercalls, but since this is only used in error paths there's * no real need. */ -static void xen_blkbk_unmap(struct xen_blkif *blkif, +static void xen_blkbk_unmap(struct xen_blkif_ring *ring, struct grant_page *pages[], int num) { @@ -768,20 +771,20 @@ static void xen_blkbk_unmap(struct xen_blkif *blkif, while (num) { unsigned int batch = min(num, BLKIF_MAX_SEGMENTS_PER_REQUEST); - - invcount = xen_blkbk_unmap_prepare(blkif, pages, batch, + + invcount = xen_blkbk_unmap_prepare(ring, pages, batch, unmap, unmap_pages); if (invcount) { ret = gnttab_unmap_refs(unmap, NULL, unmap_pages, invcount); BUG_ON(ret); - put_free_pages(blkif, unmap_pages, invcount); + put_free_pages(ring, unmap_pages, invcount); } pages += batch; num -= batch; } } -static int xen_blkbk_map(struct xen_blkif *blkif, +static int xen_blkbk_map(struct xen_blkif_ring *ring, struct grant_page *pages[], int num, bool ro) { @@ -794,6 +797,7 @@ static int xen_blkbk_map(struct xen_blkif *blkif, int ret = 0; int last_map = 0, map_until = 0; int use_persistent_gnts; + struct xen_blkif *blkif = ring->blkif; use_persistent_gnts = (blkif->vbd.feature_gnt_persistent); @@ -808,7 +812,7 @@ again: if (use_persistent_gnts) persistent_gnt = get_persistent_gnt( - blkif, + ring, pages[i]->gref); if (persistent_gnt) { @@ -819,7 +823,7 @@ again: pages[i]->page = persistent_gnt->page; pages[i]->persistent_gnt = persistent_gnt; } else { - if (get_free_page(blkif, &pages[i]->page)) + if (get_free_page(ring, &pages[i]->page)) goto out_of_memory; addr = vaddr(pages[i]->page); pages_to_gnt[segs_to_map] = pages[i]->page; @@ -852,7 +856,7 @@ again: BUG_ON(new_map_idx >= segs_to_map); if (unlikely(map[new_map_idx].status != 0)) { pr_debug("invalid buffer -- could not remap it\n"); - put_free_pages(blkif, &pages[seg_idx]->page, 1); + put_free_pages(ring, &pages[seg_idx]->page, 1); pages[seg_idx]->handle = BLKBACK_INVALID_HANDLE; ret |= 1; goto next; @@ -862,7 +866,7 @@ again: continue; } if (use_persistent_gnts && - blkif->persistent_gnt_c < xen_blkif_max_pgrants) { + ring->persistent_gnt_c < xen_blkif_max_pgrants) { /* * We are using persistent grants, the grant is * not mapped but we might have room for it. @@ -880,7 +884,7 @@ again: persistent_gnt->gnt = map[new_map_idx].ref; persistent_gnt->handle = map[new_map_idx].handle; persistent_gnt->page = pages[seg_idx]->page; - if (add_persistent_gnt(blkif, + if (add_persistent_gnt(ring, persistent_gnt)) { kfree(persistent_gnt); persistent_gnt = NULL; @@ -888,7 +892,7 @@ again: } pages[seg_idx]->persistent_gnt = persistent_gnt; pr_debug("grant %u added to the tree of persistent grants, using %u/%u\n", - persistent_gnt->gnt, blkif->persistent_gnt_c, + persistent_gnt->gnt, ring->persistent_gnt_c, xen_blkif_max_pgrants); goto next; } @@ -913,7 +917,7 @@ next: out_of_memory: pr_alert("%s: out of memory\n", __func__); - put_free_pages(blkif, pages_to_gnt, segs_to_map); + put_free_pages(ring, pages_to_gnt, segs_to_map); return -ENOMEM; } @@ -921,7 +925,7 @@ static int xen_blkbk_map_seg(struct pending_req *pending_req) { int rc; - rc = xen_blkbk_map(pending_req->blkif, pending_req->segments, + rc = xen_blkbk_map(pending_req->ring, pending_req->segments, pending_req->nr_segs, (pending_req->operation != BLKIF_OP_READ)); @@ -934,7 +938,7 @@ static int xen_blkbk_parse_indirect(struct blkif_request *req, struct phys_req *preq) { struct grant_page **pages = pending_req->indirect_pages; - struct xen_blkif *blkif = pending_req->blkif; + struct xen_blkif_ring *ring = pending_req->ring; int indirect_grefs, rc, n, nseg, i; struct blkif_request_segment *segments = NULL; @@ -945,7 +949,7 @@ static int xen_blkbk_parse_indirect(struct blkif_request *req, for (i = 0; i < indirect_grefs; i++) pages[i]->gref = req->u.indirect.indirect_grefs[i]; - rc = xen_blkbk_map(blkif, pages, indirect_grefs, true); + rc = xen_blkbk_map(ring, pages, indirect_grefs, true); if (rc) goto unmap; @@ -972,15 +976,16 @@ static int xen_blkbk_parse_indirect(struct blkif_request *req, unmap: if (segments) kunmap_atomic(segments); - xen_blkbk_unmap(blkif, pages, indirect_grefs); + xen_blkbk_unmap(ring, pages, indirect_grefs); return rc; } -static int dispatch_discard_io(struct xen_blkif *blkif, +static int dispatch_discard_io(struct xen_blkif_ring *ring, struct blkif_request *req) { int err = 0; int status = BLKIF_RSP_OKAY; + struct xen_blkif *blkif = ring->blkif; struct block_device *bdev = blkif->vbd.bdev; unsigned long secure; struct phys_req preq; @@ -997,7 +1002,7 @@ static int dispatch_discard_io(struct xen_blkif *blkif, preq.sector_number + preq.nr_sects, blkif->vbd.pdevice); goto fail_response; } - blkif->st_ds_req++; + ring->st_ds_req++; secure = (blkif->vbd.discard_secure && (req->u.discard.flag & BLKIF_DISCARD_SECURE)) ? @@ -1013,26 +1018,27 @@ fail_response: } else if (err) status = BLKIF_RSP_ERROR; - make_response(blkif, req->u.discard.id, req->operation, status); + make_response(ring, req->u.discard.id, req->operation, status); xen_blkif_put(blkif); return err; } -static int dispatch_other_io(struct xen_blkif *blkif, +static int dispatch_other_io(struct xen_blkif_ring *ring, struct blkif_request *req, struct pending_req *pending_req) { - free_req(blkif, pending_req); - make_response(blkif, req->u.other.id, req->operation, + free_req(ring, pending_req); + make_response(ring, req->u.other.id, req->operation, BLKIF_RSP_EOPNOTSUPP); return -EIO; } -static void xen_blk_drain_io(struct xen_blkif *blkif) +static void xen_blk_drain_io(struct xen_blkif_ring *ring) { + struct xen_blkif *blkif = ring->blkif; atomic_set(&blkif->drain, 1); do { - if (atomic_read(&blkif->inflight) == 0) + if (atomic_read(&ring->inflight) == 0) break; wait_for_completion_interruptible_timeout( &blkif->drain_complete, HZ); @@ -1053,12 +1059,12 @@ static void __end_block_io_op(struct pending_req *pending_req, int error) if ((pending_req->operation == BLKIF_OP_FLUSH_DISKCACHE) && (error == -EOPNOTSUPP)) { pr_debug("flush diskcache op failed, not supported\n"); - xen_blkbk_flush_diskcache(XBT_NIL, pending_req->blkif->be, 0); + xen_blkbk_flush_diskcache(XBT_NIL, pending_req->ring->blkif->be, 0); pending_req->status = BLKIF_RSP_EOPNOTSUPP; } else if ((pending_req->operation == BLKIF_OP_WRITE_BARRIER) && (error == -EOPNOTSUPP)) { pr_debug("write barrier op failed, not supported\n"); - xen_blkbk_barrier(XBT_NIL, pending_req->blkif->be, 0); + xen_blkbk_barrier(XBT_NIL, pending_req->ring->blkif->be, 0); pending_req->status = BLKIF_RSP_EOPNOTSUPP; } else if (error) { pr_debug("Buffer not up-to-date at end of operation," @@ -1092,9 +1098,9 @@ static void end_block_io_op(struct bio *bio, int error) * and transmute it to the block API to hand it over to the proper block disk. */ static int -__do_block_io_op(struct xen_blkif *blkif) +__do_block_io_op(struct xen_blkif_ring *ring) { - union blkif_back_rings *blk_rings = &blkif->blk_rings; + union blkif_back_rings *blk_rings = &ring->blk_rings; struct blkif_request req; struct pending_req *pending_req; RING_IDX rc, rp; @@ -1107,7 +1113,7 @@ __do_block_io_op(struct xen_blkif *blkif) if (RING_REQUEST_PROD_OVERFLOW(&blk_rings->common, rp)) { rc = blk_rings->common.rsp_prod_pvt; pr_warn("Frontend provided bogus ring requests (%d - %d = %d). Halting ring processing on dev=%04x\n", - rp, rc, rp - rc, blkif->vbd.pdevice); + rp, rc, rp - rc, ring->blkif->vbd.pdevice); return -EACCES; } while (rc != rp) { @@ -1120,14 +1126,14 @@ __do_block_io_op(struct xen_blkif *blkif) break; } - pending_req = alloc_req(blkif); + pending_req = alloc_req(ring); if (NULL == pending_req) { - blkif->st_oo_req++; + ring->st_oo_req++; more_to_do = 1; break; } - switch (blkif->blk_protocol) { + switch (ring->blkif->blk_protocol) { case BLKIF_PROTOCOL_NATIVE: memcpy(&req, RING_GET_REQUEST(&blk_rings->native, rc), sizeof(req)); break; @@ -1151,16 +1157,16 @@ __do_block_io_op(struct xen_blkif *blkif) case BLKIF_OP_WRITE_BARRIER: case BLKIF_OP_FLUSH_DISKCACHE: case BLKIF_OP_INDIRECT: - if (dispatch_rw_block_io(blkif, &req, pending_req)) + if (dispatch_rw_block_io(ring, &req, pending_req)) goto done; break; case BLKIF_OP_DISCARD: - free_req(blkif, pending_req); - if (dispatch_discard_io(blkif, &req)) + free_req(ring, pending_req); + if (dispatch_discard_io(ring, &req)) goto done; break; default: - if (dispatch_other_io(blkif, &req, pending_req)) + if (dispatch_other_io(ring, &req, pending_req)) goto done; break; } @@ -1173,13 +1179,13 @@ done: } static int -do_block_io_op(struct xen_blkif *blkif) +do_block_io_op(struct xen_blkif_ring *ring) { - union blkif_back_rings *blk_rings = &blkif->blk_rings; + union blkif_back_rings *blk_rings = &ring->blk_rings; int more_to_do; do { - more_to_do = __do_block_io_op(blkif); + more_to_do = __do_block_io_op(ring); if (more_to_do) break; @@ -1192,7 +1198,7 @@ do_block_io_op(struct xen_blkif *blkif) * Transmutation of the 'struct blkif_request' to a proper 'struct bio' * and call the 'submit_bio' to pass it to the underlying storage. */ -static int dispatch_rw_block_io(struct xen_blkif *blkif, +static int dispatch_rw_block_io(struct xen_blkif_ring *ring, struct blkif_request *req, struct pending_req *pending_req) { @@ -1219,17 +1225,17 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, switch (req_operation) { case BLKIF_OP_READ: - blkif->st_rd_req++; + ring->st_rd_req++; operation = READ; break; case BLKIF_OP_WRITE: - blkif->st_wr_req++; + ring->st_wr_req++; operation = WRITE_ODIRECT; break; case BLKIF_OP_WRITE_BARRIER: drain = true; case BLKIF_OP_FLUSH_DISKCACHE: - blkif->st_f_req++; + ring->st_f_req++; operation = WRITE_FLUSH; break; default: @@ -1254,7 +1260,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, preq.nr_sects = 0; - pending_req->blkif = blkif; + pending_req->ring = ring; pending_req->id = req->u.rw.id; pending_req->operation = req_operation; pending_req->status = BLKIF_RSP_OKAY; @@ -1281,12 +1287,12 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, goto fail_response; } - if (xen_vbd_translate(&preq, blkif, operation) != 0) { + if (xen_vbd_translate(&preq, ring->blkif, operation) != 0) { pr_debug("access denied: %s of [%llu,%llu] on dev=%04x\n", operation == READ ? "read" : "write", preq.sector_number, preq.sector_number + preq.nr_sects, - blkif->vbd.pdevice); + ring->blkif->vbd.pdevice); goto fail_response; } @@ -1298,7 +1304,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, if (((int)preq.sector_number|(int)seg[i].nsec) & ((bdev_logical_block_size(preq.bdev) >> 9) - 1)) { pr_debug("Misaligned I/O request from domain %d\n", - blkif->domid); + ring->blkif->domid); goto fail_response; } } @@ -1307,7 +1313,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, * issue the WRITE_FLUSH. */ if (drain) - xen_blk_drain_io(pending_req->blkif); + xen_blk_drain_io(pending_req->ring); /* * If we have failed at this point, we need to undo the M2P override, @@ -1322,8 +1328,8 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, * This corresponding xen_blkif_put is done in __end_block_io_op, or * below (in "!bio") if we are handling a BLKIF_OP_DISCARD. */ - xen_blkif_get(blkif); - atomic_inc(&blkif->inflight); + xen_blkif_get(ring->blkif); + atomic_inc(&ring->inflight); for (i = 0; i < nseg; i++) { while ((bio == NULL) || @@ -1371,19 +1377,19 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, blk_finish_plug(&plug); if (operation == READ) - blkif->st_rd_sect += preq.nr_sects; + ring->st_rd_sect += preq.nr_sects; else if (operation & WRITE) - blkif->st_wr_sect += preq.nr_sects; + ring->st_wr_sect += preq.nr_sects; return 0; fail_flush: - xen_blkbk_unmap(blkif, pending_req->segments, + xen_blkbk_unmap(ring, pending_req->segments, pending_req->nr_segs); fail_response: /* Haven't submitted any bio's yet. */ - make_response(blkif, req->u.rw.id, req_operation, BLKIF_RSP_ERROR); - free_req(blkif, pending_req); + make_response(ring, req->u.rw.id, req_operation, BLKIF_RSP_ERROR); + free_req(ring, pending_req); msleep(1); /* back off a bit */ return -EIO; @@ -1401,21 +1407,22 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, /* * Put a response on the ring on how the operation fared. */ -static void make_response(struct xen_blkif *blkif, u64 id, +static void make_response(struct xen_blkif_ring *ring, u64 id, unsigned short op, int st) { struct blkif_response resp; unsigned long flags; - union blkif_back_rings *blk_rings = &blkif->blk_rings; + union blkif_back_rings *blk_rings; int notify; resp.id = id; resp.operation = op; resp.status = st; - spin_lock_irqsave(&blkif->blk_ring_lock, flags); + spin_lock_irqsave(&ring->blk_ring_lock, flags); + blk_rings = &ring->blk_rings; /* Place on the response ring for the relevant domain. */ - switch (blkif->blk_protocol) { + switch (ring->blkif->blk_protocol) { case BLKIF_PROTOCOL_NATIVE: memcpy(RING_GET_RESPONSE(&blk_rings->native, blk_rings->native.rsp_prod_pvt), &resp, sizeof(resp)); @@ -1433,9 +1440,9 @@ static void make_response(struct xen_blkif *blkif, u64 id, } blk_rings->common.rsp_prod_pvt++; RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&blk_rings->common, notify); - spin_unlock_irqrestore(&blkif->blk_ring_lock, flags); + spin_unlock_irqrestore(&ring->blk_ring_lock, flags); if (notify) - notify_remote_via_irq(blkif->irq); + notify_remote_via_irq(ring->irq); } static int __init xen_blkif_init(void) diff --git a/drivers/block/xen-blkback/common.h b/drivers/block/xen-blkback/common.h index 45a044a..cc253d4 100644 --- a/drivers/block/xen-blkback/common.h +++ b/drivers/block/xen-blkback/common.h @@ -260,30 +260,18 @@ struct persistent_gnt { struct list_head remove_node; }; -struct xen_blkif { - /* Unique identifier for this interface. */ - domid_t domid; - unsigned int handle; +/* Per-ring information */ +struct xen_blkif_ring { /* Physical parameters of the comms window. */ unsigned int irq; - /* Comms information. */ - enum blkif_protocol blk_protocol; union blkif_back_rings blk_rings; void *blk_ring; - /* The VBD attached to this interface. */ - struct xen_vbd vbd; - /* Back pointer to the backend_info. */ - struct backend_info *be; /* Private fields. */ spinlock_t blk_ring_lock; - atomic_t refcnt; wait_queue_head_t wq; - /* for barrier (drain) requests */ - struct completion drain_complete; - atomic_t drain; atomic_t inflight; - /* One thread per one blkif. */ + /* One thread per blkif ring. */ struct task_struct *xenblkd; unsigned int waiting_reqs; @@ -321,7 +309,37 @@ struct xen_blkif { struct work_struct free_work; /* Thread shutdown wait queue. */ wait_queue_head_t shutdown_wq; + struct xen_blkif *blkif; +}; + +struct xen_blkif { + /* Unique identifier for this interface. */ + domid_t domid; + unsigned int handle; + /* Comms information. */ + enum blkif_protocol blk_protocol; + /* The VBD attached to this interface. */ + struct xen_vbd vbd; + /* Back pointer to the backend_info. */ + struct backend_info *be; + /* for barrier (drain) requests */ + struct completion drain_complete; + atomic_t drain; + atomic_t refcnt; + struct work_struct free_work; + + /* statistics */ + unsigned long st_print; + 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; unsigned int nr_ring_pages; + /* All rings for this device */ + struct xen_blkif_ring ring; }; struct seg_buf { @@ -343,7 +361,7 @@ struct grant_page { * response queued for it, with the saved 'id' passed back. */ struct pending_req { - struct xen_blkif *blkif; + struct xen_blkif_ring *ring; u64 id; int nr_segs; atomic_t pendcnt; @@ -385,7 +403,7 @@ int xen_blkif_xenbus_init(void); irqreturn_t xen_blkif_be_int(int irq, void *dev_id); int xen_blkif_schedule(void *arg); int xen_blkif_purge_persistent(void *arg); -void xen_blkbk_free_caches(struct xen_blkif *blkif); +void xen_blkbk_free_caches(struct xen_blkif_ring *ring); int xen_blkbk_flush_diskcache(struct xenbus_transaction xbt, struct backend_info *be, int state); diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c index deb3f00..6482ee3 100644 --- a/drivers/block/xen-blkback/xenbus.c +++ b/drivers/block/xen-blkback/xenbus.c @@ -88,7 +88,7 @@ static void xen_update_blkif_status(struct xen_blkif *blkif) char name[BLKBACK_NAME_LEN]; /* Not ready to connect? */ - if (!blkif->irq || !blkif->vbd.bdev) + if (!blkif->ring.irq || !blkif->vbd.bdev) return; /* Already connected? */ @@ -113,10 +113,10 @@ static void xen_update_blkif_status(struct xen_blkif *blkif) } invalidate_inode_pages2(blkif->vbd.bdev->bd_inode->i_mapping); - blkif->xenblkd = kthread_run(xen_blkif_schedule, blkif, "%s", name); - if (IS_ERR(blkif->xenblkd)) { - err = PTR_ERR(blkif->xenblkd); - blkif->xenblkd = NULL; + blkif->ring.xenblkd = kthread_run(xen_blkif_schedule, &blkif->ring, "%s", name); + if (IS_ERR(blkif->ring.xenblkd)) { + err = PTR_ERR(blkif->ring.xenblkd); + blkif->ring.xenblkd = NULL; xenbus_dev_error(blkif->be->dev, err, "start xenblkd"); return; } @@ -125,6 +125,7 @@ static void xen_update_blkif_status(struct xen_blkif *blkif) static struct xen_blkif *xen_blkif_alloc(domid_t domid) { struct xen_blkif *blkif; + struct xen_blkif_ring *ring; BUILD_BUG_ON(MAX_INDIRECT_PAGES > BLKIF_MAX_INDIRECT_PAGES_PER_REQUEST); @@ -133,41 +134,44 @@ static struct xen_blkif *xen_blkif_alloc(domid_t domid) return ERR_PTR(-ENOMEM); blkif->domid = domid; - spin_lock_init(&blkif->blk_ring_lock); + ring = &blkif->ring; + ring->blkif = blkif; + spin_lock_init(&ring->blk_ring_lock); atomic_set(&blkif->refcnt, 1); - init_waitqueue_head(&blkif->wq); + init_waitqueue_head(&ring->wq); init_completion(&blkif->drain_complete); atomic_set(&blkif->drain, 0); - blkif->st_print = jiffies; - blkif->persistent_gnts.rb_node = NULL; - spin_lock_init(&blkif->free_pages_lock); - INIT_LIST_HEAD(&blkif->free_pages); - INIT_LIST_HEAD(&blkif->persistent_purge_list); - blkif->free_pages_num = 0; - atomic_set(&blkif->persistent_gnt_in_use, 0); - atomic_set(&blkif->inflight, 0); - INIT_WORK(&blkif->persistent_purge_work, xen_blkbk_unmap_purged_grants); - - INIT_LIST_HEAD(&blkif->pending_free); + ring->st_print = jiffies; + ring->persistent_gnts.rb_node = NULL; + spin_lock_init(&ring->free_pages_lock); + INIT_LIST_HEAD(&ring->free_pages); + INIT_LIST_HEAD(&ring->persistent_purge_list); + ring->free_pages_num = 0; + atomic_set(&ring->persistent_gnt_in_use, 0); + atomic_set(&ring->inflight, 0); + INIT_WORK(&ring->persistent_purge_work, xen_blkbk_unmap_purged_grants); + + INIT_LIST_HEAD(&ring->pending_free); INIT_WORK(&blkif->free_work, xen_blkif_deferred_free); - spin_lock_init(&blkif->pending_free_lock); - init_waitqueue_head(&blkif->pending_free_wq); - init_waitqueue_head(&blkif->shutdown_wq); + spin_lock_init(&ring->pending_free_lock); + init_waitqueue_head(&ring->pending_free_wq); + init_waitqueue_head(&ring->shutdown_wq); return blkif; } -static int xen_blkif_map(struct xen_blkif *blkif, grant_ref_t *gref, +static int xen_blkif_map(struct xen_blkif_ring *ring, grant_ref_t *gref, unsigned int nr_grefs, unsigned int evtchn) { int err; + struct xen_blkif *blkif = ring->blkif; /* Already connected through? */ - if (blkif->irq) + if (ring->irq) return 0; err = xenbus_map_ring_valloc(blkif->be->dev, gref, nr_grefs, - &blkif->blk_ring); + &ring->blk_ring); if (err < 0) return err; @@ -175,22 +179,22 @@ static int xen_blkif_map(struct xen_blkif *blkif, grant_ref_t *gref, case BLKIF_PROTOCOL_NATIVE: { struct blkif_sring *sring; - sring = (struct blkif_sring *)blkif->blk_ring; - BACK_RING_INIT(&blkif->blk_rings.native, sring, PAGE_SIZE * nr_grefs); + sring = (struct blkif_sring *)ring->blk_ring; + BACK_RING_INIT(&ring->blk_rings.native, sring, PAGE_SIZE * nr_grefs); break; } case BLKIF_PROTOCOL_X86_32: { struct blkif_x86_32_sring *sring_x86_32; - sring_x86_32 = (struct blkif_x86_32_sring *)blkif->blk_ring; - BACK_RING_INIT(&blkif->blk_rings.x86_32, sring_x86_32, PAGE_SIZE * nr_grefs); + sring_x86_32 = (struct blkif_x86_32_sring *)ring->blk_ring; + BACK_RING_INIT(&ring->blk_rings.x86_32, sring_x86_32, PAGE_SIZE * nr_grefs); break; } case BLKIF_PROTOCOL_X86_64: { struct blkif_x86_64_sring *sring_x86_64; - sring_x86_64 = (struct blkif_x86_64_sring *)blkif->blk_ring; - BACK_RING_INIT(&blkif->blk_rings.x86_64, sring_x86_64, PAGE_SIZE * nr_grefs); + sring_x86_64 = (struct blkif_x86_64_sring *)ring->blk_ring; + BACK_RING_INIT(&ring->blk_rings.x86_64, sring_x86_64, PAGE_SIZE * nr_grefs); break; } default: @@ -199,44 +203,46 @@ static int xen_blkif_map(struct xen_blkif *blkif, grant_ref_t *gref, err = bind_interdomain_evtchn_to_irqhandler(blkif->domid, evtchn, xen_blkif_be_int, 0, - "blkif-backend", blkif); + "blkif-backend", ring); if (err < 0) { - xenbus_unmap_ring_vfree(blkif->be->dev, blkif->blk_ring); - blkif->blk_rings.common.sring = NULL; + xenbus_unmap_ring_vfree(blkif->be->dev, ring->blk_ring); + ring->blk_rings.common.sring = NULL; return err; } - blkif->irq = err; + ring->irq = err; return 0; } static int xen_blkif_disconnect(struct xen_blkif *blkif) { - if (blkif->xenblkd) { - kthread_stop(blkif->xenblkd); - wake_up(&blkif->shutdown_wq); - blkif->xenblkd = NULL; + struct xen_blkif_ring *ring = &blkif->ring; + + if (ring->xenblkd) { + kthread_stop(ring->xenblkd); + wake_up(&ring->shutdown_wq); + ring->xenblkd = NULL; } /* The above kthread_stop() guarantees that at this point we * don't have any discard_io or other_io requests. So, checking * for inflight IO is enough. */ - if (atomic_read(&blkif->inflight) > 0) + if (atomic_read(&ring->inflight) > 0) return -EBUSY; - if (blkif->irq) { - unbind_from_irqhandler(blkif->irq, blkif); - blkif->irq = 0; + if (ring->irq) { + unbind_from_irqhandler(ring->irq, ring); + ring->irq = 0; } - if (blkif->blk_rings.common.sring) { - xenbus_unmap_ring_vfree(blkif->be->dev, blkif->blk_ring); - blkif->blk_rings.common.sring = NULL; + if (ring->blk_rings.common.sring) { + xenbus_unmap_ring_vfree(blkif->be->dev, ring->blk_ring); + ring->blk_rings.common.sring = NULL; } /* Remove all persistent grants and the cache of ballooned pages. */ - xen_blkbk_free_caches(blkif); + xen_blkbk_free_caches(ring); return 0; } @@ -245,20 +251,21 @@ static void xen_blkif_free(struct xen_blkif *blkif) { struct pending_req *req, *n; int i = 0, j; + struct xen_blkif_ring *ring = &blkif->ring; xen_blkif_disconnect(blkif); xen_vbd_free(&blkif->vbd); /* Make sure everything is drained before shutting down */ - BUG_ON(blkif->persistent_gnt_c != 0); - BUG_ON(atomic_read(&blkif->persistent_gnt_in_use) != 0); - BUG_ON(blkif->free_pages_num != 0); - BUG_ON(!list_empty(&blkif->persistent_purge_list)); - BUG_ON(!list_empty(&blkif->free_pages)); - BUG_ON(!RB_EMPTY_ROOT(&blkif->persistent_gnts)); + BUG_ON(ring->persistent_gnt_c != 0); + BUG_ON(atomic_read(&ring->persistent_gnt_in_use) != 0); + BUG_ON(ring->free_pages_num != 0); + BUG_ON(!list_empty(&ring->persistent_purge_list)); + BUG_ON(!list_empty(&ring->free_pages)); + BUG_ON(!RB_EMPTY_ROOT(&ring->persistent_gnts)); /* Check that there is no request in use */ - list_for_each_entry_safe(req, n, &blkif->pending_free, free_list) { + list_for_each_entry_safe(req, n, &ring->pending_free, free_list) { list_del(&req->free_list); for (j = 0; j < MAX_INDIRECT_SEGMENTS; j++) @@ -298,6 +305,16 @@ int __init xen_blkif_interface_init(void) { \ struct xenbus_device *dev = to_xenbus_device(_dev); \ struct backend_info *be = dev_get_drvdata(&dev->dev); \ + struct xen_blkif *blkif = be->blkif; \ + struct xen_blkif_ring *ring = &blkif->ring; \ + \ + blkif->st_oo_req = ring->st_oo_req; \ + blkif->st_rd_req = ring->st_rd_req; \ + blkif->st_wr_req = ring->st_wr_req; \ + blkif->st_f_req = ring->st_f_req; \ + blkif->st_ds_req = ring->st_ds_req; \ + blkif->st_rd_sect = ring->st_rd_sect; \ + blkif->st_wr_sect = ring->st_wr_sect; \ \ return sprintf(buf, format, ##args); \ } \ @@ -830,6 +847,7 @@ static int connect_ring(struct backend_info *be) char protocol[64] = ""; struct pending_req *req, *n; int err, i, j; + struct xen_blkif_ring *ring = &be->blkif->ring; pr_debug("%s %s\n", __func__, dev->otherend); @@ -918,7 +936,7 @@ static int connect_ring(struct backend_info *be) req = kzalloc(sizeof(*req), GFP_KERNEL); if (!req) goto fail; - list_add_tail(&req->free_list, &be->blkif->pending_free); + list_add_tail(&req->free_list, &ring->pending_free); for (j = 0; j < MAX_INDIRECT_SEGMENTS; j++) { req->segments[j] = kzalloc(sizeof(*req->segments[0]), GFP_KERNEL); if (!req->segments[j]) @@ -933,7 +951,7 @@ static int connect_ring(struct backend_info *be) } /* Map the shared frame, irq etc. */ - err = xen_blkif_map(be->blkif, ring_ref, nr_grefs, evtchn); + err = xen_blkif_map(ring, ring_ref, nr_grefs, evtchn); if (err) { xenbus_dev_fatal(dev, err, "mapping ring-ref port %u", evtchn); return err; @@ -942,7 +960,7 @@ static int connect_ring(struct backend_info *be) return 0; fail: - list_for_each_entry_safe(req, n, &be->blkif->pending_free, free_list) { + list_for_each_entry_safe(req, n, &ring->pending_free, free_list) { list_del(&req->free_list); for (j = 0; j < MAX_INDIRECT_SEGMENTS; j++) { if (!req->segments[j]) -- 1.7.10.4