diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2015-02-13 05:54:28 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-02-13 05:54:28 +0300 |
commit | 818099574b04c5301eacbbcd441022b353a65466 (patch) | |
tree | 77b3645b375105cb0389df2b4ea5ffa90329f7f8 /drivers/block | |
parent | 802ea9d8645d33d24b7b4cd4537c14f3e698bde0 (diff) | |
parent | 6016daed58ee482a2f7684e93342e89139cf4419 (diff) | |
download | linux-818099574b04c5301eacbbcd441022b353a65466.tar.xz |
Merge branch 'akpm' (patches from Andrew)
Merge third set of updates from Andrew Morton:
- the rest of MM
[ This includes getting rid of the numa hinting bits, in favor of
just generic protnone logic. Yay. - Linus ]
- core kernel
- procfs
- some of lib/ (lots of lib/ material this time)
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (104 commits)
lib/lcm.c: replace include
lib/percpu_ida.c: remove redundant includes
lib/strncpy_from_user.c: replace module.h include
lib/stmp_device.c: replace module.h include
lib/sort.c: move include inside #if 0
lib/show_mem.c: remove redundant include
lib/radix-tree.c: change to simpler include
lib/plist.c: remove redundant include
lib/nlattr.c: remove redundant include
lib/kobject_uevent.c: remove redundant include
lib/llist.c: remove redundant include
lib/md5.c: simplify include
lib/list_sort.c: rearrange includes
lib/genalloc.c: remove redundant include
lib/idr.c: remove redundant include
lib/halfmd4.c: simplify includes
lib/dynamic_queue_limits.c: simplify includes
lib/sort.c: use simpler includes
lib/interval_tree.c: simplify includes
hexdump: make it return number of bytes placed in buffer
...
Diffstat (limited to 'drivers/block')
-rw-r--r-- | drivers/block/xen-blkfront.c | 2 | ||||
-rw-r--r-- | drivers/block/zram/zram_drv.c | 227 | ||||
-rw-r--r-- | drivers/block/zram/zram_drv.h | 21 |
3 files changed, 133 insertions, 117 deletions
diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c index 7f66d2e08f19..37779e4c4585 100644 --- a/drivers/block/xen-blkfront.c +++ b/drivers/block/xen-blkfront.c @@ -1391,7 +1391,7 @@ static int blkfront_probe(struct xenbus_device *dev, if (major != XENVBD_MAJOR) { printk(KERN_INFO "%s: HVM does not support vbd %d as xen block device\n", - __FUNCTION__, vdevice); + __func__, vdevice); return -ENODEV; } } diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index bd8bda386e02..8e233edd7a09 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -53,9 +53,9 @@ static ssize_t name##_show(struct device *d, \ } \ static DEVICE_ATTR_RO(name); -static inline int init_done(struct zram *zram) +static inline bool init_done(struct zram *zram) { - return zram->meta != NULL; + return zram->disksize; } static inline struct zram *dev_to_zram(struct device *dev) @@ -307,42 +307,67 @@ static inline int valid_io_request(struct zram *zram, return 1; } -static void zram_meta_free(struct zram_meta *meta) +static void zram_meta_free(struct zram_meta *meta, u64 disksize) { + size_t num_pages = disksize >> PAGE_SHIFT; + size_t index; + + /* Free all pages that are still in this zram device */ + for (index = 0; index < num_pages; index++) { + unsigned long handle = meta->table[index].handle; + + if (!handle) + continue; + + zs_free(meta->mem_pool, handle); + } + zs_destroy_pool(meta->mem_pool); vfree(meta->table); kfree(meta); } -static struct zram_meta *zram_meta_alloc(u64 disksize) +static struct zram_meta *zram_meta_alloc(int device_id, u64 disksize) { size_t num_pages; + char pool_name[8]; struct zram_meta *meta = kmalloc(sizeof(*meta), GFP_KERNEL); + if (!meta) - goto out; + return NULL; num_pages = disksize >> PAGE_SHIFT; meta->table = vzalloc(num_pages * sizeof(*meta->table)); if (!meta->table) { pr_err("Error allocating zram address table\n"); - goto free_meta; + goto out_error; } - meta->mem_pool = zs_create_pool(GFP_NOIO | __GFP_HIGHMEM); + snprintf(pool_name, sizeof(pool_name), "zram%d", device_id); + meta->mem_pool = zs_create_pool(pool_name, GFP_NOIO | __GFP_HIGHMEM); if (!meta->mem_pool) { pr_err("Error creating memory pool\n"); - goto free_table; + goto out_error; } return meta; -free_table: +out_error: vfree(meta->table); -free_meta: kfree(meta); - meta = NULL; -out: - return meta; + return NULL; +} + +static inline bool zram_meta_get(struct zram *zram) +{ + if (atomic_inc_not_zero(&zram->refcount)) + return true; + return false; +} + +static inline void zram_meta_put(struct zram *zram) +{ + atomic_dec(&zram->refcount); } static void update_position(u32 *index, int *offset, struct bio_vec *bvec) @@ -704,10 +729,11 @@ static void zram_bio_discard(struct zram *zram, u32 index, } } -static void zram_reset_device(struct zram *zram, bool reset_capacity) +static void zram_reset_device(struct zram *zram) { - size_t index; struct zram_meta *meta; + struct zcomp *comp; + u64 disksize; down_write(&zram->init_lock); @@ -719,36 +745,30 @@ static void zram_reset_device(struct zram *zram, bool reset_capacity) } meta = zram->meta; - /* Free all pages that are still in this zram device */ - for (index = 0; index < zram->disksize >> PAGE_SHIFT; index++) { - unsigned long handle = meta->table[index].handle; - if (!handle) - continue; - - zs_free(meta->mem_pool, handle); - } - - zcomp_destroy(zram->comp); - zram->max_comp_streams = 1; + comp = zram->comp; + disksize = zram->disksize; + /* + * Refcount will go down to 0 eventually and r/w handler + * cannot handle further I/O so it will bail out by + * check zram_meta_get. + */ + zram_meta_put(zram); + /* + * We want to free zram_meta in process context to avoid + * deadlock between reclaim path and any other locks. + */ + wait_event(zram->io_done, atomic_read(&zram->refcount) == 0); - zram_meta_free(zram->meta); - zram->meta = NULL; /* Reset stats */ memset(&zram->stats, 0, sizeof(zram->stats)); - zram->disksize = 0; - if (reset_capacity) - set_capacity(zram->disk, 0); + zram->max_comp_streams = 1; + set_capacity(zram->disk, 0); up_write(&zram->init_lock); - - /* - * Revalidate disk out of the init_lock to avoid lockdep splat. - * It's okay because disk's capacity is protected by init_lock - * so that revalidate_disk always sees up-to-date capacity. - */ - if (reset_capacity) - revalidate_disk(zram->disk); + /* I/O operation under all of CPU are done so let's free */ + zram_meta_free(meta, disksize); + zcomp_destroy(comp); } static ssize_t disksize_store(struct device *dev, @@ -765,7 +785,7 @@ static ssize_t disksize_store(struct device *dev, return -EINVAL; disksize = PAGE_ALIGN(disksize); - meta = zram_meta_alloc(disksize); + meta = zram_meta_alloc(zram->disk->first_minor, disksize); if (!meta) return -ENOMEM; @@ -784,6 +804,8 @@ static ssize_t disksize_store(struct device *dev, goto out_destroy_comp; } + init_waitqueue_head(&zram->io_done); + atomic_set(&zram->refcount, 1); zram->meta = meta; zram->comp = comp; zram->disksize = disksize; @@ -803,7 +825,7 @@ out_destroy_comp: up_write(&zram->init_lock); zcomp_destroy(comp); out_free_meta: - zram_meta_free(meta); + zram_meta_free(meta, disksize); return err; } @@ -821,8 +843,9 @@ static ssize_t reset_store(struct device *dev, if (!bdev) return -ENOMEM; + mutex_lock(&bdev->bd_mutex); /* Do not reset an active device! */ - if (bdev->bd_holders) { + if (bdev->bd_openers) { ret = -EBUSY; goto out; } @@ -838,12 +861,16 @@ static ssize_t reset_store(struct device *dev, /* Make sure all pending I/O is finished */ fsync_bdev(bdev); + zram_reset_device(zram); + + mutex_unlock(&bdev->bd_mutex); + revalidate_disk(zram->disk); bdput(bdev); - zram_reset_device(zram, true); return len; out: + mutex_unlock(&bdev->bd_mutex); bdput(bdev); return ret; } @@ -909,23 +936,21 @@ static void zram_make_request(struct request_queue *queue, struct bio *bio) { struct zram *zram = queue->queuedata; - down_read(&zram->init_lock); - if (unlikely(!init_done(zram))) + if (unlikely(!zram_meta_get(zram))) goto error; if (!valid_io_request(zram, bio->bi_iter.bi_sector, bio->bi_iter.bi_size)) { atomic64_inc(&zram->stats.invalid_io); - goto error; + goto put_zram; } __zram_make_request(zram, bio); - up_read(&zram->init_lock); - + zram_meta_put(zram); return; - +put_zram: + zram_meta_put(zram); error: - up_read(&zram->init_lock); bio_io_error(bio); } @@ -947,21 +972,19 @@ static void zram_slot_free_notify(struct block_device *bdev, static int zram_rw_page(struct block_device *bdev, sector_t sector, struct page *page, int rw) { - int offset, err; + int offset, err = -EIO; u32 index; struct zram *zram; struct bio_vec bv; zram = bdev->bd_disk->private_data; + if (unlikely(!zram_meta_get(zram))) + goto out; + if (!valid_io_request(zram, sector, PAGE_SIZE)) { atomic64_inc(&zram->stats.invalid_io); - return -EINVAL; - } - - down_read(&zram->init_lock); - if (unlikely(!init_done(zram))) { - err = -EIO; - goto out_unlock; + err = -EINVAL; + goto put_zram; } index = sector >> SECTORS_PER_PAGE_SHIFT; @@ -972,8 +995,9 @@ static int zram_rw_page(struct block_device *bdev, sector_t sector, bv.bv_offset = 0; err = zram_bvec_rw(zram, &bv, index, offset, rw); -out_unlock: - up_read(&zram->init_lock); +put_zram: + zram_meta_put(zram); +out: /* * If I/O fails, just return error(ie, non-zero) without * calling page_endio. @@ -1039,19 +1063,19 @@ static struct attribute_group zram_disk_attr_group = { static int create_device(struct zram *zram, int device_id) { + struct request_queue *queue; int ret = -ENOMEM; init_rwsem(&zram->init_lock); - zram->queue = blk_alloc_queue(GFP_KERNEL); - if (!zram->queue) { + queue = blk_alloc_queue(GFP_KERNEL); + if (!queue) { pr_err("Error allocating disk queue for device %d\n", device_id); goto out; } - blk_queue_make_request(zram->queue, zram_make_request); - zram->queue->queuedata = zram; + blk_queue_make_request(queue, zram_make_request); /* gendisk structure */ zram->disk = alloc_disk(1); @@ -1064,7 +1088,8 @@ static int create_device(struct zram *zram, int device_id) zram->disk->major = zram_major; zram->disk->first_minor = device_id; zram->disk->fops = &zram_devops; - zram->disk->queue = zram->queue; + zram->disk->queue = queue; + zram->disk->queue->queuedata = zram; zram->disk->private_data = zram; snprintf(zram->disk->disk_name, 16, "zram%d", device_id); @@ -1115,20 +1140,35 @@ out_free_disk: del_gendisk(zram->disk); put_disk(zram->disk); out_free_queue: - blk_cleanup_queue(zram->queue); + blk_cleanup_queue(queue); out: return ret; } -static void destroy_device(struct zram *zram) +static void destroy_devices(unsigned int nr) { - sysfs_remove_group(&disk_to_dev(zram->disk)->kobj, - &zram_disk_attr_group); + struct zram *zram; + unsigned int i; - del_gendisk(zram->disk); - put_disk(zram->disk); + for (i = 0; i < nr; i++) { + zram = &zram_devices[i]; + /* + * Remove sysfs first, so no one will perform a disksize + * store while we destroy the devices + */ + sysfs_remove_group(&disk_to_dev(zram->disk)->kobj, + &zram_disk_attr_group); + + zram_reset_device(zram); - blk_cleanup_queue(zram->queue); + blk_cleanup_queue(zram->disk->queue); + del_gendisk(zram->disk); + put_disk(zram->disk); + } + + kfree(zram_devices); + unregister_blkdev(zram_major, "zram"); + pr_info("Destroyed %u device(s)\n", nr); } static int __init zram_init(void) @@ -1138,64 +1178,39 @@ static int __init zram_init(void) if (num_devices > max_num_devices) { pr_warn("Invalid value for num_devices: %u\n", num_devices); - ret = -EINVAL; - goto out; + return -EINVAL; } zram_major = register_blkdev(0, "zram"); if (zram_major <= 0) { pr_warn("Unable to get major number\n"); - ret = -EBUSY; - goto out; + return -EBUSY; } /* Allocate the device array and initialize each one */ zram_devices = kzalloc(num_devices * sizeof(struct zram), GFP_KERNEL); if (!zram_devices) { - ret = -ENOMEM; - goto unregister; + unregister_blkdev(zram_major, "zram"); + return -ENOMEM; } for (dev_id = 0; dev_id < num_devices; dev_id++) { ret = create_device(&zram_devices[dev_id], dev_id); if (ret) - goto free_devices; + goto out_error; } - pr_info("Created %u device(s) ...\n", num_devices); - + pr_info("Created %u device(s)\n", num_devices); return 0; -free_devices: - while (dev_id) - destroy_device(&zram_devices[--dev_id]); - kfree(zram_devices); -unregister: - unregister_blkdev(zram_major, "zram"); -out: +out_error: + destroy_devices(dev_id); return ret; } static void __exit zram_exit(void) { - int i; - struct zram *zram; - - for (i = 0; i < num_devices; i++) { - zram = &zram_devices[i]; - - destroy_device(zram); - /* - * Shouldn't access zram->disk after destroy_device - * because destroy_device already released zram->disk. - */ - zram_reset_device(zram, false); - } - - unregister_blkdev(zram_major, "zram"); - - kfree(zram_devices); - pr_debug("Cleanup done!\n"); + destroy_devices(num_devices); } module_init(zram_init); diff --git a/drivers/block/zram/zram_drv.h b/drivers/block/zram/zram_drv.h index b05a816b09ac..17056e589146 100644 --- a/drivers/block/zram/zram_drv.h +++ b/drivers/block/zram/zram_drv.h @@ -100,24 +100,25 @@ struct zram_meta { struct zram { struct zram_meta *meta; - struct request_queue *queue; - struct gendisk *disk; struct zcomp *comp; - - /* Prevent concurrent execution of device init, reset and R/W request */ + struct gendisk *disk; + /* Prevent concurrent execution of device init */ struct rw_semaphore init_lock; /* - * This is the limit on amount of *uncompressed* worth of data - * we can store in a disk. + * the number of pages zram can consume for storing compressed data */ - u64 disksize; /* bytes */ + unsigned long limit_pages; int max_comp_streams; + struct zram_stats stats; + atomic_t refcount; /* refcount for zram_meta */ + /* wait all IO under all of cpu are done */ + wait_queue_head_t io_done; /* - * the number of pages zram can consume for storing compressed data + * This is the limit on amount of *uncompressed* worth of data + * we can store in a disk. */ - unsigned long limit_pages; - + u64 disksize; /* bytes */ char compressor[10]; }; #endif |