diff options
Diffstat (limited to 'drivers/block')
-rw-r--r-- | drivers/block/as-iosched.c | 8 | ||||
-rw-r--r-- | drivers/block/deadline-iosched.c | 8 | ||||
-rw-r--r-- | drivers/block/genhd.c | 25 | ||||
-rw-r--r-- | drivers/block/ioctl.c | 74 | ||||
-rw-r--r-- | drivers/block/ll_rw_blk.c | 111 | ||||
-rw-r--r-- | drivers/block/loop.c | 81 | ||||
-rw-r--r-- | drivers/block/pktcdvd.c | 36 |
7 files changed, 199 insertions, 144 deletions
diff --git a/drivers/block/as-iosched.c b/drivers/block/as-iosched.c index 638db06de2be..3410b4d294b9 100644 --- a/drivers/block/as-iosched.c +++ b/drivers/block/as-iosched.c @@ -1871,20 +1871,22 @@ static int as_init_queue(request_queue_t *q, elevator_t *e) if (!arq_pool) return -ENOMEM; - ad = kmalloc(sizeof(*ad), GFP_KERNEL); + ad = kmalloc_node(sizeof(*ad), GFP_KERNEL, q->node); if (!ad) return -ENOMEM; memset(ad, 0, sizeof(*ad)); ad->q = q; /* Identify what queue the data belongs to */ - ad->hash = kmalloc(sizeof(struct list_head)*AS_HASH_ENTRIES,GFP_KERNEL); + ad->hash = kmalloc_node(sizeof(struct list_head)*AS_HASH_ENTRIES, + GFP_KERNEL, q->node); if (!ad->hash) { kfree(ad); return -ENOMEM; } - ad->arq_pool = mempool_create(BLKDEV_MIN_RQ, mempool_alloc_slab, mempool_free_slab, arq_pool); + ad->arq_pool = mempool_create_node(BLKDEV_MIN_RQ, mempool_alloc_slab, + mempool_free_slab, arq_pool, q->node); if (!ad->arq_pool) { kfree(ad->hash); kfree(ad); diff --git a/drivers/block/deadline-iosched.c b/drivers/block/deadline-iosched.c index 7f79f3dd0165..4bc2fea73273 100644 --- a/drivers/block/deadline-iosched.c +++ b/drivers/block/deadline-iosched.c @@ -711,18 +711,20 @@ static int deadline_init_queue(request_queue_t *q, elevator_t *e) if (!drq_pool) return -ENOMEM; - dd = kmalloc(sizeof(*dd), GFP_KERNEL); + dd = kmalloc_node(sizeof(*dd), GFP_KERNEL, q->node); if (!dd) return -ENOMEM; memset(dd, 0, sizeof(*dd)); - dd->hash = kmalloc(sizeof(struct list_head)*DL_HASH_ENTRIES,GFP_KERNEL); + dd->hash = kmalloc_node(sizeof(struct list_head)*DL_HASH_ENTRIES, + GFP_KERNEL, q->node); if (!dd->hash) { kfree(dd); return -ENOMEM; } - dd->drq_pool = mempool_create(BLKDEV_MIN_RQ, mempool_alloc_slab, mempool_free_slab, drq_pool); + dd->drq_pool = mempool_create_node(BLKDEV_MIN_RQ, mempool_alloc_slab, + mempool_free_slab, drq_pool, q->node); if (!dd->drq_pool) { kfree(dd->hash); kfree(dd); diff --git a/drivers/block/genhd.c b/drivers/block/genhd.c index 53f7d846b747..47fd3659a061 100644 --- a/drivers/block/genhd.c +++ b/drivers/block/genhd.c @@ -40,7 +40,7 @@ static inline int major_to_index(int major) #ifdef CONFIG_PROC_FS /* get block device names in somewhat random order */ -int get_blkdev_list(char *p) +int get_blkdev_list(char *p, int used) { struct blk_major_name *n; int i, len; @@ -49,10 +49,18 @@ int get_blkdev_list(char *p) down(&block_subsys_sem); for (i = 0; i < ARRAY_SIZE(major_names); i++) { - for (n = major_names[i]; n; n = n->next) + for (n = major_names[i]; n; n = n->next) { + /* + * If the curent string plus the 5 extra characters + * in the line would run us off the page, then we're done + */ + if ((len + used + strlen(n->name) + 5) >= PAGE_SIZE) + goto page_full; len += sprintf(p+len, "%3d %s\n", n->major, n->name); + } } +page_full: up(&block_subsys_sem); return len; @@ -582,10 +590,16 @@ struct seq_operations diskstats_op = { .show = diskstats_show }; - struct gendisk *alloc_disk(int minors) { - struct gendisk *disk = kmalloc(sizeof(struct gendisk), GFP_KERNEL); + return alloc_disk_node(minors, -1); +} + +struct gendisk *alloc_disk_node(int minors, int node_id) +{ + struct gendisk *disk; + + disk = kmalloc_node(sizeof(struct gendisk), GFP_KERNEL, node_id); if (disk) { memset(disk, 0, sizeof(struct gendisk)); if (!init_disk_stats(disk)) { @@ -594,7 +608,7 @@ struct gendisk *alloc_disk(int minors) } if (minors > 1) { int size = (minors - 1) * sizeof(struct hd_struct *); - disk->part = kmalloc(size, GFP_KERNEL); + disk->part = kmalloc_node(size, GFP_KERNEL, node_id); if (!disk->part) { kfree(disk); return NULL; @@ -610,6 +624,7 @@ struct gendisk *alloc_disk(int minors) } EXPORT_SYMBOL(alloc_disk); +EXPORT_SYMBOL(alloc_disk_node); struct kobject *get_disk(struct gendisk *disk) { diff --git a/drivers/block/ioctl.c b/drivers/block/ioctl.c index 6d7bcc9da9e7..6e278474f9a8 100644 --- a/drivers/block/ioctl.c +++ b/drivers/block/ioctl.c @@ -133,11 +133,9 @@ static int put_u64(unsigned long arg, u64 val) return put_user(val, (u64 __user *)arg); } -int blkdev_ioctl(struct inode *inode, struct file *file, unsigned cmd, - unsigned long arg) +static int blkdev_locked_ioctl(struct file *file, struct block_device *bdev, + unsigned cmd, unsigned long arg) { - struct block_device *bdev = inode->i_bdev; - struct gendisk *disk = bdev->bd_disk; struct backing_dev_info *bdi; int ret, n; @@ -190,36 +188,72 @@ int blkdev_ioctl(struct inode *inode, struct file *file, unsigned cmd, return put_ulong(arg, bdev->bd_inode->i_size >> 9); case BLKGETSIZE64: return put_u64(arg, bdev->bd_inode->i_size); + } + return -ENOIOCTLCMD; +} + +static int blkdev_driver_ioctl(struct inode *inode, struct file *file, + struct gendisk *disk, unsigned cmd, unsigned long arg) +{ + int ret; + if (disk->fops->unlocked_ioctl) + return disk->fops->unlocked_ioctl(file, cmd, arg); + + if (disk->fops->ioctl) { + lock_kernel(); + ret = disk->fops->ioctl(inode, file, cmd, arg); + unlock_kernel(); + return ret; + } + + return -ENOTTY; +} + +int blkdev_ioctl(struct inode *inode, struct file *file, unsigned cmd, + unsigned long arg) +{ + struct block_device *bdev = inode->i_bdev; + struct gendisk *disk = bdev->bd_disk; + int ret, n; + + switch(cmd) { case BLKFLSBUF: if (!capable(CAP_SYS_ADMIN)) return -EACCES; - if (disk->fops->ioctl) { - ret = disk->fops->ioctl(inode, file, cmd, arg); - /* -EINVAL to handle old uncorrected drivers */ - if (ret != -EINVAL && ret != -ENOTTY) - return ret; - } + + ret = blkdev_driver_ioctl(inode, file, disk, cmd, arg); + /* -EINVAL to handle old uncorrected drivers */ + if (ret != -EINVAL && ret != -ENOTTY) + return ret; + + lock_kernel(); fsync_bdev(bdev); invalidate_bdev(bdev, 0); + unlock_kernel(); return 0; + case BLKROSET: - if (disk->fops->ioctl) { - ret = disk->fops->ioctl(inode, file, cmd, arg); - /* -EINVAL to handle old uncorrected drivers */ - if (ret != -EINVAL && ret != -ENOTTY) - return ret; - } + ret = blkdev_driver_ioctl(inode, file, disk, cmd, arg); + /* -EINVAL to handle old uncorrected drivers */ + if (ret != -EINVAL && ret != -ENOTTY) + return ret; if (!capable(CAP_SYS_ADMIN)) return -EACCES; if (get_user(n, (int __user *)(arg))) return -EFAULT; + lock_kernel(); set_device_ro(bdev, n); + unlock_kernel(); return 0; - default: - if (disk->fops->ioctl) - return disk->fops->ioctl(inode, file, cmd, arg); } - return -ENOTTY; + + lock_kernel(); + ret = blkdev_locked_ioctl(file, bdev, cmd, arg); + unlock_kernel(); + if (ret != -ENOIOCTLCMD) + return ret; + + return blkdev_driver_ioctl(inode, file, disk, cmd, arg); } /* Most of the generic ioctls are handled in the normal fallback path. diff --git a/drivers/block/ll_rw_blk.c b/drivers/block/ll_rw_blk.c index 81fe3a0c1fe7..fd94ea27d594 100644 --- a/drivers/block/ll_rw_blk.c +++ b/drivers/block/ll_rw_blk.c @@ -28,6 +28,7 @@ #include <linux/slab.h> #include <linux/swap.h> #include <linux/writeback.h> +#include <linux/blkdev.h> /* * for max sense size @@ -716,7 +717,7 @@ struct request *blk_queue_find_tag(request_queue_t *q, int tag) { struct blk_queue_tag *bqt = q->queue_tags; - if (unlikely(bqt == NULL || tag >= bqt->real_max_depth)) + if (unlikely(bqt == NULL || tag >= bqt->max_depth)) return NULL; return bqt->tag_index[tag]; @@ -774,9 +775,9 @@ EXPORT_SYMBOL(blk_queue_free_tags); static int init_tag_map(request_queue_t *q, struct blk_queue_tag *tags, int depth) { - int bits, i; struct request **tag_index; unsigned long *tag_map; + int nr_ulongs; if (depth > q->nr_requests * 2) { depth = q->nr_requests * 2; @@ -788,24 +789,17 @@ init_tag_map(request_queue_t *q, struct blk_queue_tag *tags, int depth) if (!tag_index) goto fail; - bits = (depth / BLK_TAGS_PER_LONG) + 1; - tag_map = kmalloc(bits * sizeof(unsigned long), GFP_ATOMIC); + nr_ulongs = ALIGN(depth, BITS_PER_LONG) / BITS_PER_LONG; + tag_map = kmalloc(nr_ulongs * sizeof(unsigned long), GFP_ATOMIC); if (!tag_map) goto fail; memset(tag_index, 0, depth * sizeof(struct request *)); - memset(tag_map, 0, bits * sizeof(unsigned long)); + memset(tag_map, 0, nr_ulongs * sizeof(unsigned long)); tags->max_depth = depth; - tags->real_max_depth = bits * BITS_PER_LONG; tags->tag_index = tag_index; tags->tag_map = tag_map; - /* - * set the upper bits if the depth isn't a multiple of the word size - */ - for (i = depth; i < bits * BLK_TAGS_PER_LONG; i++) - __set_bit(i, tag_map); - return 0; fail: kfree(tag_index); @@ -870,32 +864,24 @@ int blk_queue_resize_tags(request_queue_t *q, int new_depth) struct blk_queue_tag *bqt = q->queue_tags; struct request **tag_index; unsigned long *tag_map; - int bits, max_depth; + int max_depth, nr_ulongs; if (!bqt) return -ENXIO; /* - * don't bother sizing down - */ - if (new_depth <= bqt->real_max_depth) { - bqt->max_depth = new_depth; - return 0; - } - - /* * save the old state info, so we can copy it back */ tag_index = bqt->tag_index; tag_map = bqt->tag_map; - max_depth = bqt->real_max_depth; + max_depth = bqt->max_depth; if (init_tag_map(q, bqt, new_depth)) return -ENOMEM; memcpy(bqt->tag_index, tag_index, max_depth * sizeof(struct request *)); - bits = max_depth / BLK_TAGS_PER_LONG; - memcpy(bqt->tag_map, tag_map, bits * sizeof(unsigned long)); + nr_ulongs = ALIGN(max_depth, BITS_PER_LONG) / BITS_PER_LONG; + memcpy(bqt->tag_map, tag_map, nr_ulongs * sizeof(unsigned long)); kfree(tag_index); kfree(tag_map); @@ -925,11 +911,16 @@ void blk_queue_end_tag(request_queue_t *q, struct request *rq) BUG_ON(tag == -1); - if (unlikely(tag >= bqt->real_max_depth)) + if (unlikely(tag >= bqt->max_depth)) + /* + * This can happen after tag depth has been reduced. + * FIXME: how about a warning or info message here? + */ return; if (unlikely(!__test_and_clear_bit(tag, bqt->tag_map))) { - printk("attempt to clear non-busy tag (%d)\n", tag); + printk(KERN_ERR "%s: attempt to clear non-busy tag (%d)\n", + __FUNCTION__, tag); return; } @@ -938,7 +929,8 @@ void blk_queue_end_tag(request_queue_t *q, struct request *rq) rq->tag = -1; if (unlikely(bqt->tag_index[tag] == NULL)) - printk("tag %d is missing\n", tag); + printk(KERN_ERR "%s: tag %d is missing\n", + __FUNCTION__, tag); bqt->tag_index[tag] = NULL; bqt->busy--; @@ -967,24 +959,20 @@ EXPORT_SYMBOL(blk_queue_end_tag); int blk_queue_start_tag(request_queue_t *q, struct request *rq) { struct blk_queue_tag *bqt = q->queue_tags; - unsigned long *map = bqt->tag_map; - int tag = 0; + int tag; if (unlikely((rq->flags & REQ_QUEUED))) { printk(KERN_ERR - "request %p for device [%s] already tagged %d", - rq, rq->rq_disk ? rq->rq_disk->disk_name : "?", rq->tag); + "%s: request %p for device [%s] already tagged %d", + __FUNCTION__, rq, + rq->rq_disk ? rq->rq_disk->disk_name : "?", rq->tag); BUG(); } - for (map = bqt->tag_map; *map == -1UL; map++) { - tag += BLK_TAGS_PER_LONG; - - if (tag >= bqt->max_depth) - return 1; - } + tag = find_first_zero_bit(bqt->tag_map, bqt->max_depth); + if (tag >= bqt->max_depth) + return 1; - tag += ffz(*map); __set_bit(tag, bqt->tag_map); rq->flags |= REQ_QUEUED; @@ -1020,7 +1008,8 @@ void blk_queue_invalidate_tags(request_queue_t *q) rq = list_entry_rq(tmp); if (rq->tag == -1) { - printk("bad tag found on list\n"); + printk(KERN_ERR + "%s: bad tag found on list\n", __FUNCTION__); list_del_init(&rq->queuelist); rq->flags &= ~REQ_QUEUED; } else @@ -1450,7 +1439,7 @@ EXPORT_SYMBOL(blk_remove_plug); */ void __generic_unplug_device(request_queue_t *q) { - if (test_bit(QUEUE_FLAG_STOPPED, &q->queue_flags)) + if (unlikely(test_bit(QUEUE_FLAG_STOPPED, &q->queue_flags))) return; if (!blk_remove_plug(q)) @@ -1645,7 +1634,8 @@ static int blk_init_free_list(request_queue_t *q) init_waitqueue_head(&rl->wait[WRITE]); init_waitqueue_head(&rl->drain); - rl->rq_pool = mempool_create(BLKDEV_MIN_RQ, mempool_alloc_slab, mempool_free_slab, request_cachep); + rl->rq_pool = mempool_create_node(BLKDEV_MIN_RQ, mempool_alloc_slab, + mempool_free_slab, request_cachep, q->node); if (!rl->rq_pool) return -ENOMEM; @@ -1657,8 +1647,15 @@ static int __make_request(request_queue_t *, struct bio *); request_queue_t *blk_alloc_queue(int gfp_mask) { - request_queue_t *q = kmem_cache_alloc(requestq_cachep, gfp_mask); + return blk_alloc_queue_node(gfp_mask, -1); +} +EXPORT_SYMBOL(blk_alloc_queue); + +request_queue_t *blk_alloc_queue_node(int gfp_mask, int node_id) +{ + request_queue_t *q; + q = kmem_cache_alloc_node(requestq_cachep, gfp_mask, node_id); if (!q) return NULL; @@ -1671,8 +1668,7 @@ request_queue_t *blk_alloc_queue(int gfp_mask) return q; } - -EXPORT_SYMBOL(blk_alloc_queue); +EXPORT_SYMBOL(blk_alloc_queue_node); /** * blk_init_queue - prepare a request queue for use with a block device @@ -1705,13 +1701,22 @@ EXPORT_SYMBOL(blk_alloc_queue); * blk_init_queue() must be paired with a blk_cleanup_queue() call * when the block device is deactivated (such as at module unload). **/ + request_queue_t *blk_init_queue(request_fn_proc *rfn, spinlock_t *lock) { - request_queue_t *q = blk_alloc_queue(GFP_KERNEL); + return blk_init_queue_node(rfn, lock, -1); +} +EXPORT_SYMBOL(blk_init_queue); + +request_queue_t * +blk_init_queue_node(request_fn_proc *rfn, spinlock_t *lock, int node_id) +{ + request_queue_t *q = blk_alloc_queue_node(GFP_KERNEL, node_id); if (!q) return NULL; + q->node = node_id; if (blk_init_free_list(q)) goto out_init; @@ -1754,12 +1759,11 @@ out_init: kmem_cache_free(requestq_cachep, q); return NULL; } - -EXPORT_SYMBOL(blk_init_queue); +EXPORT_SYMBOL(blk_init_queue_node); int blk_get_queue(request_queue_t *q) { - if (!test_bit(QUEUE_FLAG_DEAD, &q->queue_flags)) { + if (likely(!test_bit(QUEUE_FLAG_DEAD, &q->queue_flags))) { atomic_inc(&q->refcnt); return 0; } @@ -1838,7 +1842,6 @@ static void __freed_request(request_queue_t *q, int rw) clear_queue_congested(q, rw); if (rl->count[rw] + 1 <= q->nr_requests) { - smp_mb(); if (waitqueue_active(&rl->wait[rw])) wake_up(&rl->wait[rw]); @@ -1966,7 +1969,6 @@ static struct request *get_request_wait(request_queue_t *q, int rw) DEFINE_WAIT(wait); struct request *rq; - generic_unplug_device(q); do { struct request_list *rl = &q->rq; @@ -1978,6 +1980,7 @@ static struct request *get_request_wait(request_queue_t *q, int rw) if (!rq) { struct io_context *ioc; + generic_unplug_device(q); io_schedule(); /* @@ -2581,7 +2584,7 @@ static int __make_request(request_queue_t *q, struct bio *bio) spin_lock_prefetch(q->queue_lock); barrier = bio_barrier(bio); - if (barrier && (q->ordered == QUEUE_ORDERED_NONE)) { + if (unlikely(barrier) && (q->ordered == QUEUE_ORDERED_NONE)) { err = -EOPNOTSUPP; goto end_io; } @@ -2682,7 +2685,7 @@ get_rq: /* * REQ_BARRIER implies no merging, but lets make it explicit */ - if (barrier) + if (unlikely(barrier)) req->flags |= (REQ_HARDBARRIER | REQ_NOMERGE); req->errors = 0; @@ -2806,7 +2809,7 @@ static inline void block_wait_queue_running(request_queue_t *q) { DEFINE_WAIT(wait); - while (test_bit(QUEUE_FLAG_DRAIN, &q->queue_flags)) { + while (unlikely(test_bit(QUEUE_FLAG_DRAIN, &q->queue_flags))) { struct request_list *rl = &q->rq; prepare_to_wait_exclusive(&rl->drain, &wait, @@ -2915,7 +2918,7 @@ end_io: goto end_io; } - if (test_bit(QUEUE_FLAG_DEAD, &q->queue_flags)) + if (unlikely(test_bit(QUEUE_FLAG_DEAD, &q->queue_flags))) goto end_io; block_wait_queue_running(q); diff --git a/drivers/block/loop.c b/drivers/block/loop.c index 6f011d0d8e97..b35e08876dd4 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -472,17 +472,11 @@ static int do_bio_filebacked(struct loop_device *lo, struct bio *bio) */ static void loop_add_bio(struct loop_device *lo, struct bio *bio) { - unsigned long flags; - - spin_lock_irqsave(&lo->lo_lock, flags); if (lo->lo_biotail) { lo->lo_biotail->bi_next = bio; lo->lo_biotail = bio; } else lo->lo_bio = lo->lo_biotail = bio; - spin_unlock_irqrestore(&lo->lo_lock, flags); - - up(&lo->lo_bh_mutex); } /* @@ -492,14 +486,12 @@ static struct bio *loop_get_bio(struct loop_device *lo) { struct bio *bio; - spin_lock_irq(&lo->lo_lock); if ((bio = lo->lo_bio)) { if (bio == lo->lo_biotail) lo->lo_biotail = NULL; lo->lo_bio = bio->bi_next; bio->bi_next = NULL; } - spin_unlock_irq(&lo->lo_lock); return bio; } @@ -509,35 +501,28 @@ static int loop_make_request(request_queue_t *q, struct bio *old_bio) struct loop_device *lo = q->queuedata; int rw = bio_rw(old_bio); - if (!lo) - goto out; + if (rw == READA) + rw = READ; + + BUG_ON(!lo || (rw != READ && rw != WRITE)); spin_lock_irq(&lo->lo_lock); if (lo->lo_state != Lo_bound) - goto inactive; - atomic_inc(&lo->lo_pending); - spin_unlock_irq(&lo->lo_lock); - - if (rw == WRITE) { - if (lo->lo_flags & LO_FLAGS_READ_ONLY) - goto err; - } else if (rw == READA) { - rw = READ; - } else if (rw != READ) { - printk(KERN_ERR "loop: unknown command (%x)\n", rw); - goto err; - } + goto out; + if (unlikely(rw == WRITE && (lo->lo_flags & LO_FLAGS_READ_ONLY))) + goto out; + lo->lo_pending++; loop_add_bio(lo, old_bio); + spin_unlock_irq(&lo->lo_lock); + up(&lo->lo_bh_mutex); return 0; -err: - if (atomic_dec_and_test(&lo->lo_pending)) - up(&lo->lo_bh_mutex); + out: + if (lo->lo_pending == 0) + up(&lo->lo_bh_mutex); + spin_unlock_irq(&lo->lo_lock); bio_io_error(old_bio, old_bio->bi_size); return 0; -inactive: - spin_unlock_irq(&lo->lo_lock); - goto out; } /* @@ -560,13 +545,11 @@ static void do_loop_switch(struct loop_device *, struct switch_request *); static inline void loop_handle_bio(struct loop_device *lo, struct bio *bio) { - int ret; - if (unlikely(!bio->bi_bdev)) { do_loop_switch(lo, bio->bi_private); bio_put(bio); } else { - ret = do_bio_filebacked(lo, bio); + int ret = do_bio_filebacked(lo, bio); bio_endio(bio, bio->bi_size, ret); } } @@ -594,7 +577,7 @@ static int loop_thread(void *data) set_user_nice(current, -20); lo->lo_state = Lo_bound; - atomic_inc(&lo->lo_pending); + lo->lo_pending = 1; /* * up sem, we are running @@ -602,26 +585,37 @@ static int loop_thread(void *data) up(&lo->lo_sem); for (;;) { - down_interruptible(&lo->lo_bh_mutex); + int pending; + /* - * could be upped because of tear-down, not because of - * pending work + * interruptible just to not contribute to load avg */ - if (!atomic_read(&lo->lo_pending)) + if (down_interruptible(&lo->lo_bh_mutex)) + continue; + + spin_lock_irq(&lo->lo_lock); + + /* + * could be upped because of tear-down, not pending work + */ + if (unlikely(!lo->lo_pending)) { + spin_unlock_irq(&lo->lo_lock); break; + } bio = loop_get_bio(lo); - if (!bio) { - printk("loop: missing bio\n"); - continue; - } + lo->lo_pending--; + pending = lo->lo_pending; + spin_unlock_irq(&lo->lo_lock); + + BUG_ON(!bio); loop_handle_bio(lo, bio); /* * upped both for pending work and tear-down, lo_pending * will hit zero then */ - if (atomic_dec_and_test(&lo->lo_pending)) + if (unlikely(!pending)) break; } @@ -900,7 +894,8 @@ static int loop_clr_fd(struct loop_device *lo, struct block_device *bdev) spin_lock_irq(&lo->lo_lock); lo->lo_state = Lo_rundown; - if (atomic_dec_and_test(&lo->lo_pending)) + lo->lo_pending--; + if (!lo->lo_pending) up(&lo->lo_bh_mutex); spin_unlock_irq(&lo->lo_lock); diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c index bc56770bcc90..7f3d78de265c 100644 --- a/drivers/block/pktcdvd.c +++ b/drivers/block/pktcdvd.c @@ -467,14 +467,12 @@ static int pkt_set_speed(struct pktcdvd_device *pd, unsigned write_speed, unsign * Queue a bio for processing by the low-level CD device. Must be called * from process context. */ -static void pkt_queue_bio(struct pktcdvd_device *pd, struct bio *bio, int high_prio_read) +static void pkt_queue_bio(struct pktcdvd_device *pd, struct bio *bio) { spin_lock(&pd->iosched.lock); if (bio_data_dir(bio) == READ) { pkt_add_list_last(bio, &pd->iosched.read_queue, &pd->iosched.read_queue_tail); - if (high_prio_read) - pd->iosched.high_prio_read = 1; } else { pkt_add_list_last(bio, &pd->iosched.write_queue, &pd->iosched.write_queue_tail); @@ -490,15 +488,16 @@ static void pkt_queue_bio(struct pktcdvd_device *pd, struct bio *bio, int high_p * requirements for CDRW drives: * - A cache flush command must be inserted before a read request if the * previous request was a write. - * - Switching between reading and writing is slow, so don't it more often + * - Switching between reading and writing is slow, so don't do it more often * than necessary. + * - Optimize for throughput at the expense of latency. This means that streaming + * writes will never be interrupted by a read, but if the drive has to seek + * before the next write, switch to reading instead if there are any pending + * read requests. * - Set the read speed according to current usage pattern. When only reading * from the device, it's best to use the highest possible read speed, but * when switching often between reading and writing, it's better to have the * same read and write speeds. - * - Reads originating from user space should have higher priority than reads - * originating from pkt_gather_data, because some process is usually waiting - * on reads of the first kind. */ static void pkt_iosched_process_queue(struct pktcdvd_device *pd) { @@ -512,21 +511,24 @@ static void pkt_iosched_process_queue(struct pktcdvd_device *pd) for (;;) { struct bio *bio; - int reads_queued, writes_queued, high_prio_read; + int reads_queued, writes_queued; spin_lock(&pd->iosched.lock); reads_queued = (pd->iosched.read_queue != NULL); writes_queued = (pd->iosched.write_queue != NULL); - if (!reads_queued) - pd->iosched.high_prio_read = 0; - high_prio_read = pd->iosched.high_prio_read; spin_unlock(&pd->iosched.lock); if (!reads_queued && !writes_queued) break; if (pd->iosched.writing) { - if (high_prio_read || (!writes_queued && reads_queued)) { + int need_write_seek = 1; + spin_lock(&pd->iosched.lock); + bio = pd->iosched.write_queue; + spin_unlock(&pd->iosched.lock); + if (bio && (bio->bi_sector == pd->iosched.last_write)) + need_write_seek = 0; + if (need_write_seek && reads_queued) { if (atomic_read(&pd->cdrw.pending_bios) > 0) { VPRINTK("pktcdvd: write, waiting\n"); break; @@ -559,8 +561,10 @@ static void pkt_iosched_process_queue(struct pktcdvd_device *pd) if (bio_data_dir(bio) == READ) pd->iosched.successive_reads += bio->bi_size >> 10; - else + else { pd->iosched.successive_reads = 0; + pd->iosched.last_write = bio->bi_sector + bio_sectors(bio); + } if (pd->iosched.successive_reads >= HI_SPEED_SWITCH) { if (pd->read_speed == pd->write_speed) { pd->read_speed = MAX_SPEED; @@ -765,7 +769,7 @@ static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt) atomic_inc(&pkt->io_wait); bio->bi_rw = READ; - pkt_queue_bio(pd, bio, 0); + pkt_queue_bio(pd, bio); frames_read++; } @@ -1062,7 +1066,7 @@ static void pkt_start_write(struct pktcdvd_device *pd, struct packet_data *pkt) atomic_set(&pkt->io_wait, 1); pkt->w_bio->bi_rw = WRITE; - pkt_queue_bio(pd, pkt->w_bio, 0); + pkt_queue_bio(pd, pkt->w_bio); } static void pkt_finish_packet(struct packet_data *pkt, int uptodate) @@ -2120,7 +2124,7 @@ static int pkt_make_request(request_queue_t *q, struct bio *bio) cloned_bio->bi_private = psd; cloned_bio->bi_end_io = pkt_end_io_read_cloned; pd->stats.secs_r += bio->bi_size >> 9; - pkt_queue_bio(pd, cloned_bio, 1); + pkt_queue_bio(pd, cloned_bio); return 0; } |