diff options
Diffstat (limited to 'fs/btrfs/ioctl.c')
-rw-r--r-- | fs/btrfs/ioctl.c | 483 |
1 files changed, 472 insertions, 11 deletions
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 226c91fe31a7..c9302d193187 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -29,6 +29,7 @@ #include <linux/fileattr.h> #include <linux/fsverity.h> #include <linux/sched/xacct.h> +#include <linux/io_uring/cmd.h> #include "ctree.h" #include "disk-io.h" #include "export.h" @@ -1048,7 +1049,6 @@ static noinline int btrfs_mksnapshot(const struct path *parent, struct btrfs_qgroup_inherit *inherit) { int ret; - bool snapshot_force_cow = false; /* * Force new buffered writes to reserve space even when NOCOW is @@ -1067,15 +1067,13 @@ static noinline int btrfs_mksnapshot(const struct path *parent, * creation. */ atomic_inc(&root->snapshot_force_cow); - snapshot_force_cow = true; btrfs_wait_ordered_extents(root, U64_MAX, NULL); ret = btrfs_mksubvol(parent, idmap, name, namelen, root, readonly, inherit); + atomic_dec(&root->snapshot_force_cow); out: - if (snapshot_force_cow) - atomic_dec(&root->snapshot_force_cow); btrfs_drew_read_unlock(&root->snapshot_lock); return ret; } @@ -1308,9 +1306,9 @@ static noinline int __btrfs_ioctl_snap_create(struct file *file, ret = btrfs_mksubvol(&file->f_path, idmap, name, namelen, NULL, readonly, inherit); } else { - struct fd src = fdget(fd); + CLASS(fd, src)(fd); struct inode *src_inode; - if (!fd_file(src)) { + if (fd_empty(src)) { ret = -EINVAL; goto out_drop_write; } @@ -1341,7 +1339,6 @@ static noinline int __btrfs_ioctl_snap_create(struct file *file, BTRFS_I(src_inode)->root, readonly, inherit); } - fdput(src); } out_drop_write: mnt_drop_write_file(file); @@ -4058,8 +4055,7 @@ static long btrfs_ioctl_quota_rescan_status(struct btrfs_fs_info *fs_info, return 0; } -static long btrfs_ioctl_quota_rescan_wait(struct btrfs_fs_info *fs_info, - void __user *arg) +static long btrfs_ioctl_quota_rescan_wait(struct btrfs_fs_info *fs_info) { if (!capable(CAP_SYS_ADMIN)) return -EPERM; @@ -4514,12 +4510,17 @@ static int btrfs_ioctl_encoded_read(struct file *file, void __user *argp, size_t copy_end_kernel = offsetofend(struct btrfs_ioctl_encoded_io_args, flags); size_t copy_end; + struct btrfs_inode *inode = BTRFS_I(file_inode(file)); + struct btrfs_fs_info *fs_info = inode->root->fs_info; + struct extent_io_tree *io_tree = &inode->io_tree; struct iovec iovstack[UIO_FASTIOV]; struct iovec *iov = iovstack; struct iov_iter iter; loff_t pos; struct kiocb kiocb; ssize_t ret; + u64 disk_bytenr, disk_io_size; + struct extent_state *cached_state = NULL; if (!capable(CAP_SYS_ADMIN)) { ret = -EPERM; @@ -4572,7 +4573,32 @@ static int btrfs_ioctl_encoded_read(struct file *file, void __user *argp, init_sync_kiocb(&kiocb, file); kiocb.ki_pos = pos; - ret = btrfs_encoded_read(&kiocb, &iter, &args); + ret = btrfs_encoded_read(&kiocb, &iter, &args, &cached_state, + &disk_bytenr, &disk_io_size); + + if (ret == -EIOCBQUEUED) { + bool unlocked = false; + u64 start, lockend, count; + + start = ALIGN_DOWN(kiocb.ki_pos, fs_info->sectorsize); + lockend = start + BTRFS_MAX_UNCOMPRESSED - 1; + + if (args.compression) + count = disk_io_size; + else + count = args.len; + + ret = btrfs_encoded_read_regular(&kiocb, &iter, start, lockend, + &cached_state, disk_bytenr, + disk_io_size, count, + args.compression, &unlocked); + + if (!unlocked) { + unlock_extent(io_tree, start, lockend, &cached_state); + btrfs_inode_unlock(inode, BTRFS_ILOCK_SHARED); + } + } + if (ret >= 0) { fsnotify_access(file); if (copy_to_user(argp + copy_end, @@ -4690,6 +4716,439 @@ out_acct: return ret; } +/* + * Context that's attached to an encoded read io_uring command, in cmd->pdu. It + * contains the fields in btrfs_uring_read_extent that are necessary to finish + * off and cleanup the I/O in btrfs_uring_read_finished. + */ +struct btrfs_uring_priv { + struct io_uring_cmd *cmd; + struct page **pages; + unsigned long nr_pages; + struct kiocb iocb; + struct iovec *iov; + struct iov_iter iter; + struct extent_state *cached_state; + u64 count; + u64 start; + u64 lockend; + int err; + bool compressed; +}; + +struct io_btrfs_cmd { + struct btrfs_uring_priv *priv; +}; + +static void btrfs_uring_read_finished(struct io_uring_cmd *cmd, unsigned int issue_flags) +{ + struct io_btrfs_cmd *bc = io_uring_cmd_to_pdu(cmd, struct io_btrfs_cmd); + struct btrfs_uring_priv *priv = bc->priv; + struct btrfs_inode *inode = BTRFS_I(file_inode(priv->iocb.ki_filp)); + struct extent_io_tree *io_tree = &inode->io_tree; + unsigned long index; + u64 cur; + size_t page_offset; + ssize_t ret; + + if (priv->err) { + ret = priv->err; + goto out; + } + + if (priv->compressed) { + index = 0; + page_offset = 0; + } else { + index = (priv->iocb.ki_pos - priv->start) >> PAGE_SHIFT; + page_offset = offset_in_page(priv->iocb.ki_pos - priv->start); + } + cur = 0; + while (cur < priv->count) { + size_t bytes = min_t(size_t, priv->count - cur, PAGE_SIZE - page_offset); + + if (copy_page_to_iter(priv->pages[index], page_offset, bytes, + &priv->iter) != bytes) { + ret = -EFAULT; + goto out; + } + + index++; + cur += bytes; + page_offset = 0; + } + ret = priv->count; + +out: + unlock_extent(io_tree, priv->start, priv->lockend, &priv->cached_state); + btrfs_inode_unlock(inode, BTRFS_ILOCK_SHARED); + + io_uring_cmd_done(cmd, ret, 0, issue_flags); + add_rchar(current, ret); + + for (index = 0; index < priv->nr_pages; index++) + __free_page(priv->pages[index]); + + kfree(priv->pages); + kfree(priv->iov); + kfree(priv); +} + +void btrfs_uring_read_extent_endio(void *ctx, int err) +{ + struct btrfs_uring_priv *priv = ctx; + struct io_btrfs_cmd *bc = io_uring_cmd_to_pdu(priv->cmd, struct io_btrfs_cmd); + + priv->err = err; + bc->priv = priv; + + io_uring_cmd_complete_in_task(priv->cmd, btrfs_uring_read_finished); +} + +static int btrfs_uring_read_extent(struct kiocb *iocb, struct iov_iter *iter, + u64 start, u64 lockend, + struct extent_state *cached_state, + u64 disk_bytenr, u64 disk_io_size, + size_t count, bool compressed, + struct iovec *iov, struct io_uring_cmd *cmd) +{ + struct btrfs_inode *inode = BTRFS_I(file_inode(iocb->ki_filp)); + struct extent_io_tree *io_tree = &inode->io_tree; + struct page **pages; + struct btrfs_uring_priv *priv = NULL; + unsigned long nr_pages; + int ret; + + nr_pages = DIV_ROUND_UP(disk_io_size, PAGE_SIZE); + pages = kcalloc(nr_pages, sizeof(struct page *), GFP_NOFS); + if (!pages) + return -ENOMEM; + ret = btrfs_alloc_page_array(nr_pages, pages, 0); + if (ret) { + ret = -ENOMEM; + goto out_fail; + } + + priv = kmalloc(sizeof(*priv), GFP_NOFS); + if (!priv) { + ret = -ENOMEM; + goto out_fail; + } + + priv->iocb = *iocb; + priv->iov = iov; + priv->iter = *iter; + priv->count = count; + priv->cmd = cmd; + priv->cached_state = cached_state; + priv->compressed = compressed; + priv->nr_pages = nr_pages; + priv->pages = pages; + priv->start = start; + priv->lockend = lockend; + priv->err = 0; + + ret = btrfs_encoded_read_regular_fill_pages(inode, disk_bytenr, + disk_io_size, pages, priv); + if (ret && ret != -EIOCBQUEUED) + goto out_fail; + + /* + * If we return -EIOCBQUEUED, we're deferring the cleanup to + * btrfs_uring_read_finished(), which will handle unlocking the extent + * and inode and freeing the allocations. + */ + + return -EIOCBQUEUED; + +out_fail: + unlock_extent(io_tree, start, lockend, &cached_state); + btrfs_inode_unlock(inode, BTRFS_ILOCK_SHARED); + kfree(priv); + return ret; +} + +static int btrfs_uring_encoded_read(struct io_uring_cmd *cmd, unsigned int issue_flags) +{ + size_t copy_end_kernel = offsetofend(struct btrfs_ioctl_encoded_io_args, flags); + size_t copy_end; + struct btrfs_ioctl_encoded_io_args args = { 0 }; + int ret; + u64 disk_bytenr, disk_io_size; + struct file *file; + struct btrfs_inode *inode; + struct btrfs_fs_info *fs_info; + struct extent_io_tree *io_tree; + struct iovec iovstack[UIO_FASTIOV]; + struct iovec *iov = iovstack; + struct iov_iter iter; + loff_t pos; + struct kiocb kiocb; + struct extent_state *cached_state = NULL; + u64 start, lockend; + void __user *sqe_addr; + + if (!capable(CAP_SYS_ADMIN)) { + ret = -EPERM; + goto out_acct; + } + file = cmd->file; + inode = BTRFS_I(file->f_inode); + fs_info = inode->root->fs_info; + io_tree = &inode->io_tree; + sqe_addr = u64_to_user_ptr(READ_ONCE(cmd->sqe->addr)); + + if (issue_flags & IO_URING_F_COMPAT) { +#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT) + struct btrfs_ioctl_encoded_io_args_32 args32; + + copy_end = offsetofend(struct btrfs_ioctl_encoded_io_args_32, flags); + if (copy_from_user(&args32, sqe_addr, copy_end)) { + ret = -EFAULT; + goto out_acct; + } + args.iov = compat_ptr(args32.iov); + args.iovcnt = args32.iovcnt; + args.offset = args32.offset; + args.flags = args32.flags; +#else + return -ENOTTY; +#endif + } else { + copy_end = copy_end_kernel; + if (copy_from_user(&args, sqe_addr, copy_end)) { + ret = -EFAULT; + goto out_acct; + } + } + + if (args.flags != 0) + return -EINVAL; + + ret = import_iovec(ITER_DEST, args.iov, args.iovcnt, ARRAY_SIZE(iovstack), + &iov, &iter); + if (ret < 0) + goto out_acct; + + if (iov_iter_count(&iter) == 0) { + ret = 0; + goto out_free; + } + + pos = args.offset; + ret = rw_verify_area(READ, file, &pos, args.len); + if (ret < 0) + goto out_free; + + init_sync_kiocb(&kiocb, file); + kiocb.ki_pos = pos; + + if (issue_flags & IO_URING_F_NONBLOCK) + kiocb.ki_flags |= IOCB_NOWAIT; + + start = ALIGN_DOWN(pos, fs_info->sectorsize); + lockend = start + BTRFS_MAX_UNCOMPRESSED - 1; + + ret = btrfs_encoded_read(&kiocb, &iter, &args, &cached_state, + &disk_bytenr, &disk_io_size); + if (ret < 0 && ret != -EIOCBQUEUED) + goto out_free; + + file_accessed(file); + + if (copy_to_user(sqe_addr + copy_end, (const char *)&args + copy_end_kernel, + sizeof(args) - copy_end_kernel)) { + if (ret == -EIOCBQUEUED) { + unlock_extent(io_tree, start, lockend, &cached_state); + btrfs_inode_unlock(inode, BTRFS_ILOCK_SHARED); + } + ret = -EFAULT; + goto out_free; + } + + if (ret == -EIOCBQUEUED) { + u64 count; + + /* + * If we've optimized things by storing the iovecs on the stack, + * undo this. + */ + if (!iov) { + iov = kmalloc(sizeof(struct iovec) * args.iovcnt, GFP_NOFS); + if (!iov) { + unlock_extent(io_tree, start, lockend, &cached_state); + btrfs_inode_unlock(inode, BTRFS_ILOCK_SHARED); + ret = -ENOMEM; + goto out_acct; + } + + memcpy(iov, iovstack, sizeof(struct iovec) * args.iovcnt); + } + + count = min_t(u64, iov_iter_count(&iter), disk_io_size); + + /* Match ioctl by not returning past EOF if uncompressed. */ + if (!args.compression) + count = min_t(u64, count, args.len); + + ret = btrfs_uring_read_extent(&kiocb, &iter, start, lockend, + cached_state, disk_bytenr, + disk_io_size, count, + args.compression, iov, cmd); + + goto out_acct; + } + +out_free: + kfree(iov); + +out_acct: + if (ret > 0) + add_rchar(current, ret); + inc_syscr(current); + + return ret; +} + +int btrfs_uring_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags) +{ + switch (cmd->cmd_op) { + case BTRFS_IOC_ENCODED_READ: +#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT) + case BTRFS_IOC_ENCODED_READ_32: +#endif + return btrfs_uring_encoded_read(cmd, issue_flags); + } + + return -EINVAL; +} + +static int btrfs_ioctl_subvol_sync(struct btrfs_fs_info *fs_info, void __user *argp) +{ + struct btrfs_root *root; + struct btrfs_ioctl_subvol_wait args = { 0 }; + signed long sched_ret; + int refs; + u64 root_flags; + bool wait_for_deletion = false; + bool found = false; + + if (copy_from_user(&args, argp, sizeof(args))) + return -EFAULT; + + switch (args.mode) { + case BTRFS_SUBVOL_SYNC_WAIT_FOR_QUEUED: + /* + * Wait for the first one deleted that waits until all previous + * are cleaned. + */ + spin_lock(&fs_info->trans_lock); + if (!list_empty(&fs_info->dead_roots)) { + root = list_last_entry(&fs_info->dead_roots, + struct btrfs_root, root_list); + args.subvolid = btrfs_root_id(root); + found = true; + } + spin_unlock(&fs_info->trans_lock); + if (!found) + return -ENOENT; + + fallthrough; + case BTRFS_SUBVOL_SYNC_WAIT_FOR_ONE: + if ((0 < args.subvolid && args.subvolid < BTRFS_FIRST_FREE_OBJECTID) || + BTRFS_LAST_FREE_OBJECTID < args.subvolid) + return -EINVAL; + break; + case BTRFS_SUBVOL_SYNC_COUNT: + spin_lock(&fs_info->trans_lock); + args.count = list_count_nodes(&fs_info->dead_roots); + spin_unlock(&fs_info->trans_lock); + if (copy_to_user(argp, &args, sizeof(args))) + return -EFAULT; + return 0; + case BTRFS_SUBVOL_SYNC_PEEK_FIRST: + spin_lock(&fs_info->trans_lock); + /* Last in the list was deleted first. */ + if (!list_empty(&fs_info->dead_roots)) { + root = list_last_entry(&fs_info->dead_roots, + struct btrfs_root, root_list); + args.subvolid = btrfs_root_id(root); + } else { + args.subvolid = 0; + } + spin_unlock(&fs_info->trans_lock); + if (copy_to_user(argp, &args, sizeof(args))) + return -EFAULT; + return 0; + case BTRFS_SUBVOL_SYNC_PEEK_LAST: + spin_lock(&fs_info->trans_lock); + /* First in the list was deleted last. */ + if (!list_empty(&fs_info->dead_roots)) { + root = list_first_entry(&fs_info->dead_roots, + struct btrfs_root, root_list); + args.subvolid = btrfs_root_id(root); + } else { + args.subvolid = 0; + } + spin_unlock(&fs_info->trans_lock); + if (copy_to_user(argp, &args, sizeof(args))) + return -EFAULT; + return 0; + default: + return -EINVAL; + } + + /* 32bit limitation: fs_roots_radix key is not wide enough. */ + if (sizeof(unsigned long) != sizeof(u64) && args.subvolid > U32_MAX) + return -EOVERFLOW; + + while (1) { + /* Wait for the specific one. */ + if (down_read_interruptible(&fs_info->subvol_sem) == -EINTR) + return -EINTR; + refs = -1; + spin_lock(&fs_info->fs_roots_radix_lock); + root = radix_tree_lookup(&fs_info->fs_roots_radix, + (unsigned long)args.subvolid); + if (root) { + spin_lock(&root->root_item_lock); + refs = btrfs_root_refs(&root->root_item); + root_flags = btrfs_root_flags(&root->root_item); + spin_unlock(&root->root_item_lock); + } + spin_unlock(&fs_info->fs_roots_radix_lock); + up_read(&fs_info->subvol_sem); + + /* Subvolume does not exist. */ + if (!root) + return -ENOENT; + + /* Subvolume not deleted at all. */ + if (refs > 0) + return -EEXIST; + /* We've waited and now the subvolume is gone. */ + if (wait_for_deletion && refs == -1) { + /* Return the one we waited for as the last one. */ + if (copy_to_user(argp, &args, sizeof(args))) + return -EFAULT; + return 0; + } + + /* Subvolume not found on the first try (deleted or never existed). */ + if (refs == -1) + return -ENOENT; + + wait_for_deletion = true; + ASSERT(root_flags & BTRFS_ROOT_SUBVOL_DEAD); + sched_ret = schedule_timeout_interruptible(HZ); + /* Early wake up or error. */ + if (sched_ret != 0) + return -EINTR; + } + + return 0; +} + long btrfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { @@ -4812,7 +5271,7 @@ long btrfs_ioctl(struct file *file, unsigned int case BTRFS_IOC_QUOTA_RESCAN_STATUS: return btrfs_ioctl_quota_rescan_status(fs_info, argp); case BTRFS_IOC_QUOTA_RESCAN_WAIT: - return btrfs_ioctl_quota_rescan_wait(fs_info, argp); + return btrfs_ioctl_quota_rescan_wait(fs_info); case BTRFS_IOC_DEV_REPLACE: return btrfs_ioctl_dev_replace(fs_info, argp); case BTRFS_IOC_GET_SUPPORTED_FEATURES: @@ -4841,6 +5300,8 @@ long btrfs_ioctl(struct file *file, unsigned int case BTRFS_IOC_ENCODED_WRITE_32: return btrfs_ioctl_encoded_write(file, argp, true); #endif + case BTRFS_IOC_SUBVOL_SYNC_WAIT: + return btrfs_ioctl_subvol_sync(fs_info, argp); } return -ENOTTY; |