> 2023年7月4日 20:21，Jan Kara <jack@xxxxxxx> 写道： > > Convert bcache to use blkdev_get_handle_by_path() and pass the handle > around. > > CC: linux-bcache@xxxxxxxxxxxxxxx > CC: Coly Li <colyli@xxxxxxx > CC: Kent Overstreet <kent.overstreet@xxxxxxxxx> > Signed-off-by: Jan Kara <jack@xxxxxxx> Acked-by: Coly Li <colyli@xxxxxxx <mailto:colyli@xxxxxxx>> Thanks. Coly Li > --- > drivers/md/bcache/bcache.h | 2 + > drivers/md/bcache/super.c | 79 ++++++++++++++++++++------------------ > 2 files changed, 44 insertions(+), 37 deletions(-) > > diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h > index 5a79bb3c272f..2aa3f2c1f719 100644 > --- a/drivers/md/bcache/bcache.h > +++ b/drivers/md/bcache/bcache.h > @@ -299,6 +299,7 @@ struct cached_dev { > struct list_head list; > struct bcache_device disk; > struct block_device *bdev; > + struct bdev_handle *bdev_handle; > > struct cache_sb sb; > struct cache_sb_disk *sb_disk; > @@ -421,6 +422,7 @@ struct cache { > > struct kobject kobj; > struct block_device *bdev; > + struct bdev_handle *bdev_handle; > > struct task_struct *alloc_thread; > > diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c > index 0ae2b3676293..2b3f35fd7477 100644 > --- a/drivers/md/bcache/super.c > +++ b/drivers/md/bcache/super.c > @@ -1368,8 +1368,8 @@ static void cached_dev_free(struct closure *cl) > if (dc->sb_disk) > put_page(virt_to_page(dc->sb_disk)); > > - if (!IS_ERR_OR_NULL(dc->bdev)) > - blkdev_put(dc->bdev, dc); > + if (dc->bdev_handle) > + blkdev_handle_put(dc->bdev_handle); > > wake_up(&unregister_wait); > > @@ -1444,7 +1444,7 @@ static int cached_dev_init(struct cached_dev *dc, unsigned int block_size) > /* Cached device - bcache superblock */ > > static int register_bdev(struct cache_sb *sb, struct cache_sb_disk *sb_disk, > - struct block_device *bdev, > + struct bdev_handle *bdev_handle, > struct cached_dev *dc) > { > const char *err = "cannot allocate memory"; > @@ -1452,14 +1452,15 @@ static int register_bdev(struct cache_sb *sb, struct cache_sb_disk *sb_disk, > int ret = -ENOMEM; > > memcpy(&dc->sb, sb, sizeof(struct cache_sb)); > - dc->bdev = bdev; > + dc->bdev_handle = bdev_handle; > + dc->bdev = bdev_handle->bdev; > dc->sb_disk = sb_disk; > > if (cached_dev_init(dc, sb->block_size << 9)) > goto err; > > err = "error creating kobject"; > - if (kobject_add(&dc->disk.kobj, bdev_kobj(bdev), "bcache")) > + if (kobject_add(&dc->disk.kobj, bdev_kobj(dc->bdev), "bcache")) > goto err; > if (bch_cache_accounting_add_kobjs(&dc->accounting, &dc->disk.kobj)) > goto err; > @@ -2216,8 +2217,8 @@ void bch_cache_release(struct kobject *kobj) > if (ca->sb_disk) > put_page(virt_to_page(ca->sb_disk)); > > - if (!IS_ERR_OR_NULL(ca->bdev)) > - blkdev_put(ca->bdev, ca); > + if (ca->bdev_handle) > + blkdev_handle_put(ca->bdev_handle); > > kfree(ca); > module_put(THIS_MODULE); > @@ -2337,16 +2338,18 @@ static int cache_alloc(struct cache *ca) > } > > static int register_cache(struct cache_sb *sb, struct cache_sb_disk *sb_disk, > - struct block_device *bdev, struct cache *ca) > + struct bdev_handle *bdev_handle, > + struct cache *ca) > { > const char *err = NULL; /* must be set for any error case */ > int ret = 0; > > memcpy(&ca->sb, sb, sizeof(struct cache_sb)); > - ca->bdev = bdev; > + ca->bdev_handle = bdev_handle; > + ca->bdev = bdev_handle->bdev; > ca->sb_disk = sb_disk; > > - if (bdev_max_discard_sectors((bdev))) > + if (bdev_max_discard_sectors((bdev_handle->bdev))) > ca->discard = CACHE_DISCARD(&ca->sb); > > ret = cache_alloc(ca); > @@ -2354,10 +2357,10 @@ static int register_cache(struct cache_sb *sb, struct cache_sb_disk *sb_disk, > /* > * If we failed here, it means ca->kobj is not initialized yet, > * kobject_put() won't be called and there is no chance to > - * call blkdev_put() to bdev in bch_cache_release(). So we > - * explicitly call blkdev_put() here. > + * call blkdev_handle_put() to bdev in bch_cache_release(). So > + * we explicitly call blkdev_handle_put() here. > */ > - blkdev_put(bdev, ca); > + blkdev_handle_put(bdev_handle); > if (ret == -ENOMEM) > err = "cache_alloc(): -ENOMEM"; > else if (ret == -EPERM) > @@ -2367,7 +2370,7 @@ static int register_cache(struct cache_sb *sb, struct cache_sb_disk *sb_disk, > goto err; > } > > - if (kobject_add(&ca->kobj, bdev_kobj(bdev), "bcache")) { > + if (kobject_add(&ca->kobj, bdev_kobj(bdev_handle->bdev), "bcache")) { > err = "error calling kobject_add"; > ret = -ENOMEM; > goto out; > @@ -2382,14 +2385,14 @@ static int register_cache(struct cache_sb *sb, struct cache_sb_disk *sb_disk, > goto out; > } > > - pr_info("registered cache device %pg\n", ca->bdev); > + pr_info("registered cache device %pg\n", ca->bdev_handle->bdev); > > out: > kobject_put(&ca->kobj); > > err: > if (err) > - pr_notice("error %pg: %s\n", ca->bdev, err); > + pr_notice("error %pg: %s\n", ca->bdev_handle->bdev, err); > > return ret; > } > @@ -2445,7 +2448,7 @@ struct async_reg_args { > char *path; > struct cache_sb *sb; > struct cache_sb_disk *sb_disk; > - struct block_device *bdev; > + struct bdev_handle *bdev_handle; > void *holder; > }; > > @@ -2456,8 +2459,8 @@ static void register_bdev_worker(struct work_struct *work) > container_of(work, struct async_reg_args, reg_work.work); > > mutex_lock(&bch_register_lock); > - if (register_bdev(args->sb, args->sb_disk, args->bdev, args->holder) > - < 0) > + if (register_bdev(args->sb, args->sb_disk, args->bdev_handle, > + args->holder) < 0) > fail = true; > mutex_unlock(&bch_register_lock); > > @@ -2477,7 +2480,8 @@ static void register_cache_worker(struct work_struct *work) > container_of(work, struct async_reg_args, reg_work.work); > > /* blkdev_put() will be called in bch_cache_release() */ > - if (register_cache(args->sb, args->sb_disk, args->bdev, args->holder)) > + if (register_cache(args->sb, args->sb_disk, args->bdev_handle, > + args->holder)) > fail = true; > > if (fail) > @@ -2514,7 +2518,7 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr, > char *path = NULL; > struct cache_sb *sb; > struct cache_sb_disk *sb_disk; > - struct block_device *bdev, *bdev2; > + struct bdev_handle *bdev_handle, *bdev_handle2; > void *holder = NULL; > ssize_t ret; > bool async_registration = false; > @@ -2547,15 +2551,16 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr, > > ret = -EINVAL; > err = "failed to open device"; > - bdev = blkdev_get_by_path(strim(path), BLK_OPEN_READ, NULL, NULL); > - if (IS_ERR(bdev)) > + bdev_handle = blkdev_get_handle_by_path(strim(path), BLK_OPEN_READ, > + NULL, NULL); > + if (IS_ERR(bdev_handle)) > goto out_free_sb; > > err = "failed to set blocksize"; > - if (set_blocksize(bdev, 4096)) > + if (set_blocksize(bdev_handle->bdev, 4096)) > goto out_blkdev_put; > > - err = read_super(sb, bdev, &sb_disk); > + err = read_super(sb, bdev_handle->bdev, &sb_disk); > if (err) > goto out_blkdev_put; > > @@ -2567,13 +2572,13 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr, > } > > /* Now reopen in exclusive mode with proper holder */ > - bdev2 = blkdev_get_by_dev(bdev->bd_dev, BLK_OPEN_READ | BLK_OPEN_WRITE, > - holder, NULL); > - blkdev_put(bdev, NULL); > - bdev = bdev2; > - if (IS_ERR(bdev)) { > - ret = PTR_ERR(bdev); > - bdev = NULL; > + bdev_handle2 = blkdev_get_handle_by_dev(bdev_handle->bdev->bd_dev, > + BLK_OPEN_READ | BLK_OPEN_WRITE, holder, NULL); > + blkdev_handle_put(bdev_handle); > + bdev_handle = bdev_handle2; > + if (IS_ERR(bdev_handle)) { > + ret = PTR_ERR(bdev_handle); > + bdev_handle = NULL; > if (ret == -EBUSY) { > dev_t dev; > > @@ -2608,7 +2613,7 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr, > args->path = path; > args->sb = sb; > args->sb_disk = sb_disk; > - args->bdev = bdev; > + args->bdev_handle = bdev_handle; > args->holder = holder; > register_device_async(args); > /* No wait and returns to user space */ > @@ -2617,14 +2622,14 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr, > > if (SB_IS_BDEV(sb)) { > mutex_lock(&bch_register_lock); > - ret = register_bdev(sb, sb_disk, bdev, holder); > + ret = register_bdev(sb, sb_disk, bdev_handle, holder); > mutex_unlock(&bch_register_lock); > /* blkdev_put() will be called in cached_dev_free() */ > if (ret < 0) > goto out_free_sb; > } else { > /* blkdev_put() will be called in bch_cache_release() */ > - ret = register_cache(sb, sb_disk, bdev, holder); > + ret = register_cache(sb, sb_disk, bdev_handle, holder); > if (ret) > goto out_free_sb; > } > @@ -2640,8 +2645,8 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr, > out_put_sb_page: > put_page(virt_to_page(sb_disk)); > out_blkdev_put: > - if (bdev) > - blkdev_put(bdev, holder); > + if (bdev_handle) > + blkdev_handle_put(bdev_handle); > out_free_sb: > kfree(sb); > out_free_path: > -- > 2.35.3 >
