diff options
| -rw-r--r-- | drivers/xen/blkback/blkback.c | 81 |
1 files changed, 47 insertions, 34 deletions
diff --git a/drivers/xen/blkback/blkback.c b/drivers/xen/blkback/blkback.c index d07ad5318a8..2d413930f23 100644 --- a/drivers/xen/blkback/blkback.c +++ b/drivers/xen/blkback/blkback.c @@ -63,8 +63,8 @@ module_param_named(reqs, blkif_reqs, int, 0); MODULE_PARM_DESC(reqs, "Number of blkback requests to allocate"); /* Run-time switchable: /sys/module/blkback/parameters/ */ -static unsigned int log_stats = 0; -static unsigned int debug_lvl = 0; +static unsigned int log_stats; +static unsigned int debug_lvl; module_param(log_stats, int, 0644); module_param(debug_lvl, int, 0644); @@ -74,7 +74,7 @@ module_param(debug_lvl, int, 0644); * the pendcnt towards zero. When it hits zero, the specified domain has a * response queued for it, with the saved 'id' passed back. */ -typedef struct { +struct pending_req { struct blkif_st *blkif; u64 id; int nr_pages; @@ -82,12 +82,12 @@ typedef struct { unsigned short operation; int status; struct list_head free_list; -} pending_req_t; +}; #define BLKBACK_INVALID_HANDLE (~0) struct xen_blkbk { - pending_req_t *pending_reqs; + struct pending_req *pending_reqs; /* List of all 'pending_req' available */ struct list_head pending_free; /* And its spinlock. */ @@ -106,14 +106,15 @@ static struct xen_blkbk *blkbk; * pending_pages[..]. For each 'pending_req' we have have up to * BLKIF_MAX_SEGMENTS_PER_REQUEST (11) pages. The seg would be from 0 through * 10 and would index in the pending_pages[..]. */ -static inline int vaddr_pagenr(pending_req_t *req, int seg) +static inline int vaddr_pagenr(struct pending_req *req, int seg) { - return (req - blkbk->pending_reqs) * BLKIF_MAX_SEGMENTS_PER_REQUEST + seg; + return (req - blkbk->pending_reqs) * + BLKIF_MAX_SEGMENTS_PER_REQUEST + seg; } #define pending_page(req, seg) pending_pages[vaddr_pagenr(req, seg)] -static inline unsigned long vaddr(pending_req_t *req, int seg) +static inline unsigned long vaddr(struct pending_req *req, int seg) { unsigned long pfn = page_to_pfn(blkbk->pending_page(req, seg)); return (unsigned long)pfn_to_kaddr(pfn); @@ -126,21 +127,22 @@ static inline unsigned long vaddr(pending_req_t *req, int seg) static int do_block_io_op(struct blkif_st *blkif); static void dispatch_rw_block_io(struct blkif_st *blkif, struct blkif_request *req, - pending_req_t *pending_req); + struct pending_req *pending_req); static void make_response(struct blkif_st *blkif, u64 id, unsigned short op, int st); /* * Retrieve from the 'pending_reqs' a free pending_req structure to be used. */ -static pending_req_t* alloc_req(void) +static struct pending_req *alloc_req(void) { - pending_req_t *req = NULL; + struct pending_req *req = NULL; unsigned long flags; spin_lock_irqsave(&blkbk->pending_free_lock, flags); if (!list_empty(&blkbk->pending_free)) { - req = list_entry(blkbk->pending_free.next, pending_req_t, free_list); + req = list_entry(blkbk->pending_free.next, struct pending_req, + free_list); list_del(&req->free_list); } spin_unlock_irqrestore(&blkbk->pending_free_lock, flags); @@ -151,7 +153,7 @@ static pending_req_t* alloc_req(void) * 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(pending_req_t *req) +static void free_req(struct pending_req *req) { unsigned long flags; int was_empty; @@ -200,7 +202,7 @@ static void plug_queue(struct blkif_st *blkif, struct block_device *bdev) * Unmap the grant references, and also remove the M2P over-rides * used in the 'pending_req'. */ -static void fast_flush_area(pending_req_t *req) +static void fast_flush_area(struct pending_req *req) { struct gnttab_unmap_grant_ref unmap[BLKIF_MAX_SEGMENTS_PER_REQUEST]; unsigned int i, invcount = 0; @@ -221,7 +223,8 @@ static void fast_flush_area(pending_req_t *req) GNTTABOP_unmap_grant_ref, unmap, invcount); BUG_ON(ret); /* Note, we use invcount, so nr->pages, so we can't index - * using vaddr(req, i). */ + * using vaddr(req, i). + */ for (i = 0; i < invcount; i++) { ret = m2p_remove_override( virt_to_page(unmap[i].host_addr), false); @@ -233,7 +236,7 @@ static void fast_flush_area(pending_req_t *req) } } -/****************************************************************** +/* * SCHEDULER FUNCTIONS */ @@ -269,7 +272,8 @@ int blkif_schedule(void *arg) blkif->waiting_reqs || kthread_should_stop()); wait_event_interruptible( blkbk->pending_free_wq, - !list_empty(&blkbk->pending_free) || kthread_should_stop()); + !list_empty(&blkbk->pending_free) || + kthread_should_stop()); blkif->waiting_reqs = 0; smp_mb(); /* clear flag *before* checking for work */ @@ -297,7 +301,7 @@ int blkif_schedule(void *arg) * Completion callback on the bio's. Called as bh->b_end_io() */ -static void __end_block_io_op(pending_req_t *pending_req, int error) +static void __end_block_io_op(struct pending_req *pending_req, int error) { /* An error fails the entire request. */ if ((pending_req->operation == BLKIF_OP_WRITE_BARRIER) && @@ -313,7 +317,8 @@ static void __end_block_io_op(pending_req_t *pending_req, int error) /* If all of the bio's have completed it is time to unmap * the grant references associated with 'request' and provide - * the proper response on the ring. */ + * the proper response on the ring. + */ if (atomic_dec_and_test(&pending_req->pendcnt)) { fast_flush_area(pending_req); make_response(pending_req->blkif, pending_req->id, @@ -360,7 +365,7 @@ static int do_block_io_op(struct blkif_st *blkif) { union blkif_back_rings *blk_rings = &blkif->blk_rings; struct blkif_request req; - pending_req_t *pending_req; + struct pending_req *pending_req; RING_IDX rc, rp; int more_to_do = 0; @@ -440,7 +445,7 @@ static int do_block_io_op(struct blkif_st *blkif) */ static void dispatch_rw_block_io(struct blkif_st *blkif, struct blkif_request *req, - pending_req_t *pending_req) + struct pending_req *pending_req) { struct gnttab_map_grant_ref map[BLKIF_MAX_SEGMENTS_PER_REQUEST]; struct phys_req preq; @@ -487,7 +492,8 @@ static void dispatch_rw_block_io(struct blkif_st *blkif, /* Fill out preq.nr_sects with proper amount of sectors, and setup * assign map[..] with the PFN of the page in our domain with the - * corresponding grant reference for each page.*/ + * corresponding grant reference for each page. + */ for (i = 0; i < nseg; i++) { uint32_t flags; @@ -509,8 +515,9 @@ static void dispatch_rw_block_io(struct blkif_st *blkif, BUG_ON(ret); /* Now swizzel the MFN in our domain with the MFN from the other domain - * so that when we access vaddr(pending_req,i) it has the contents of the - * page from the other domain. */ + * so that when we access vaddr(pending_req,i) it has the contents of + * the page from the other domain. + */ for (i = 0; i < nseg; i++) { if (unlikely(map[i].status != 0)) { DPRINTK("invalid buffer -- could not remap it\n"); @@ -522,12 +529,13 @@ static void dispatch_rw_block_io(struct blkif_st *blkif, if (ret) continue; - + ret = m2p_add_override(PFN_DOWN(map[i].dev_bus_addr), blkbk->pending_page(pending_req, i), false); if (ret) { printk(KERN_ALERT "Failed to install M2P override for"\ - " %lx (ret: %d)\n", (unsigned long)map[i].dev_bus_addr, ret); + " %lx (ret: %d)\n", (unsigned long) + map[i].dev_bus_addr, ret); /* We could switch over to GNTTABOP_copy */ continue; } @@ -536,9 +544,11 @@ static void dispatch_rw_block_io(struct blkif_st *blkif, (req->u.rw.seg[i].first_sect << 9); } - /* If we have failed at this point, we need to undo the M2P override, set - * gnttab_set_unmap_op on all of the grant references and perform the - * hypercall to unmap the grants - that is all done in fast_flush_area. */ + /* If we have failed at this point, we need to undo the M2P override, + * set gnttab_set_unmap_op on all of the grant references and perform + * the hypercall to unmap the grants - that is all done in + * fast_flush_area. + */ if (ret) goto fail_flush; @@ -554,7 +564,8 @@ static void dispatch_rw_block_io(struct blkif_st *blkif, plug_queue(blkif, preq.bdev); /* We set it one so that the last submit_bio does not have to call - * atomic_inc. */ + * atomic_inc. + */ atomic_set(&pending_req->pendcnt, 1); blkif_get(blkif); @@ -575,7 +586,7 @@ static void dispatch_rw_block_io(struct blkif_st *blkif, atomic_inc(&pending_req->pendcnt); submit_bio(operation, bio); } - + bio = bio_alloc(GFP_KERNEL, nseg-i); if (unlikely(bio == NULL)) goto fail_put_bio; @@ -694,7 +705,7 @@ static int __init blkif_init(void) if (!xen_pv_domain()) return -ENODEV; - blkbk = (struct xen_blkbk *)kzalloc(sizeof(struct xen_blkbk), GFP_KERNEL); + blkbk = kzalloc(sizeof(struct xen_blkbk), GFP_KERNEL); if (!blkbk) { printk(KERN_ALERT "%s: out of memory!\n", __func__); return -ENOMEM; @@ -709,7 +720,8 @@ static int __init blkif_init(void) blkbk->pending_pages = kzalloc(sizeof(blkbk->pending_pages[0]) * mmap_pages, GFP_KERNEL); - if (!blkbk->pending_reqs || !blkbk->pending_grant_handles || !blkbk->pending_pages) { + if (!blkbk->pending_reqs || !blkbk->pending_grant_handles || + !blkbk->pending_pages) { rc = -ENOMEM; goto out_of_memory; } @@ -733,7 +745,8 @@ static int __init blkif_init(void) init_waitqueue_head(&blkbk->pending_free_wq); for (i = 0; i < blkif_reqs; i++) - list_add_tail(&blkbk->pending_reqs[i].free_list, &blkbk->pending_free); + list_add_tail(&blkbk->pending_reqs[i].free_list, + &blkbk->pending_free); rc = blkif_xenbus_init(); if (rc) |