X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=fs%2Fbtrfs%2Fioctl.c;h=5b22d45d3c6a232aeed49b24cf34bb374a96ecc9;hb=325a86b65c01408dc77690fac1a7a45c844a613b;hp=0de21213d05d2dd7edd5e0122bb639e569897155;hpb=dba60f3f5d564167118cad151a7d41dfe8d2a5f7;p=firefly-linux-kernel-4.4.55.git diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 0de21213d05d..5b22d45d3c6a 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -1243,7 +1243,7 @@ int btrfs_defrag_file(struct inode *inode, struct file *file, } defrag_count += ret; - balance_dirty_pages_ratelimited_nr(inode->i_mapping, ret); + balance_dirty_pages_ratelimited(inode->i_mapping); mutex_unlock(&inode->i_mutex); if (newer_than) { @@ -1339,7 +1339,8 @@ static noinline int btrfs_ioctl_resize(struct file *file, if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running, 1)) { pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n"); - return -EINPROGRESS; + mnt_drop_write_file(file); + return -EINVAL; } mutex_lock(&root->fs_info->volume_mutex); @@ -1445,8 +1446,8 @@ out_free: kfree(vol_args); out: mutex_unlock(&root->fs_info->volume_mutex); - mnt_drop_write_file(file); atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0); + mnt_drop_write_file(file); return ret; } @@ -2185,19 +2186,20 @@ static int btrfs_ioctl_defrag(struct file *file, void __user *argp) struct btrfs_ioctl_defrag_range_args *range; int ret; - if (btrfs_root_readonly(root)) - return -EROFS; + ret = mnt_want_write_file(file); + if (ret) + return ret; if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running, 1)) { pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n"); - return -EINPROGRESS; + mnt_drop_write_file(file); + return -EINVAL; } - ret = mnt_want_write_file(file); - if (ret) { - atomic_set(&root->fs_info->mutually_exclusive_operation_running, - 0); - return ret; + + if (btrfs_root_readonly(root)) { + ret = -EROFS; + goto out; } switch (inode->i_mode & S_IFMT) { @@ -2249,8 +2251,8 @@ static int btrfs_ioctl_defrag(struct file *file, void __user *argp) ret = -EINVAL; } out: - mnt_drop_write_file(file); atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0); + mnt_drop_write_file(file); return ret; } @@ -2265,7 +2267,7 @@ static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg) if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running, 1)) { pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n"); - return -EINPROGRESS; + return -EINVAL; } mutex_lock(&root->fs_info->volume_mutex); @@ -2302,7 +2304,7 @@ static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg) 1)) { pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n"); mnt_drop_write_file(file); - return -EINPROGRESS; + return -EINVAL; } mutex_lock(&root->fs_info->volume_mutex); @@ -2318,8 +2320,8 @@ static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg) kfree(vol_args); out: mutex_unlock(&root->fs_info->volume_mutex); - mnt_drop_write_file(file); atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0); + mnt_drop_write_file(file); return ret; } @@ -3439,8 +3441,8 @@ static long btrfs_ioctl_balance(struct file *file, void __user *arg) struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_ioctl_balance_args *bargs; struct btrfs_balance_control *bctl; + bool need_unlock; /* for mut. excl. ops lock */ int ret; - int need_to_clear_lock = 0; if (!capable(CAP_SYS_ADMIN)) return -EPERM; @@ -3449,14 +3451,61 @@ static long btrfs_ioctl_balance(struct file *file, void __user *arg) if (ret) return ret; - mutex_lock(&fs_info->volume_mutex); +again: + if (!atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) { + mutex_lock(&fs_info->volume_mutex); + mutex_lock(&fs_info->balance_mutex); + need_unlock = true; + goto locked; + } + + /* + * mut. excl. ops lock is locked. Three possibilites: + * (1) some other op is running + * (2) balance is running + * (3) balance is paused -- special case (think resume) + */ mutex_lock(&fs_info->balance_mutex); + if (fs_info->balance_ctl) { + /* this is either (2) or (3) */ + if (!atomic_read(&fs_info->balance_running)) { + mutex_unlock(&fs_info->balance_mutex); + if (!mutex_trylock(&fs_info->volume_mutex)) + goto again; + mutex_lock(&fs_info->balance_mutex); + + if (fs_info->balance_ctl && + !atomic_read(&fs_info->balance_running)) { + /* this is (3) */ + need_unlock = false; + goto locked; + } + + mutex_unlock(&fs_info->balance_mutex); + mutex_unlock(&fs_info->volume_mutex); + goto again; + } else { + /* this is (2) */ + mutex_unlock(&fs_info->balance_mutex); + ret = -EINPROGRESS; + goto out; + } + } else { + /* this is (1) */ + mutex_unlock(&fs_info->balance_mutex); + pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n"); + ret = -EINVAL; + goto out; + } + +locked: + BUG_ON(!atomic_read(&fs_info->mutually_exclusive_operation_running)); if (arg) { bargs = memdup_user(arg, sizeof(*bargs)); if (IS_ERR(bargs)) { ret = PTR_ERR(bargs); - goto out; + goto out_unlock; } if (bargs->flags & BTRFS_BALANCE_RESUME) { @@ -3476,13 +3525,10 @@ static long btrfs_ioctl_balance(struct file *file, void __user *arg) bargs = NULL; } - if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running, - 1)) { - pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n"); + if (fs_info->balance_ctl) { ret = -EINPROGRESS; goto out_bargs; } - need_to_clear_lock = 1; bctl = kzalloc(sizeof(*bctl), GFP_NOFS); if (!bctl) { @@ -3503,11 +3549,17 @@ static long btrfs_ioctl_balance(struct file *file, void __user *arg) } do_balance: - ret = btrfs_balance(bctl, bargs); /* - * bctl is freed in __cancel_balance or in free_fs_info if - * restriper was paused all the way until unmount + * Ownership of bctl and mutually_exclusive_operation_running + * goes to to btrfs_balance. bctl is freed in __cancel_balance, + * or, if restriper was paused all the way until unmount, in + * free_fs_info. mutually_exclusive_operation_running is + * cleared in __cancel_balance. */ + need_unlock = false; + + ret = btrfs_balance(bctl, bargs); + if (arg) { if (copy_to_user(arg, bargs, sizeof(*bargs))) ret = -EFAULT; @@ -3515,12 +3567,12 @@ do_balance: out_bargs: kfree(bargs); -out: - if (need_to_clear_lock) - atomic_set(&root->fs_info->mutually_exclusive_operation_running, - 0); +out_unlock: mutex_unlock(&fs_info->balance_mutex); mutex_unlock(&fs_info->volume_mutex); + if (need_unlock) + atomic_set(&fs_info->mutually_exclusive_operation_running, 0); +out: mnt_drop_write_file(file); return ret; }