diff options
| -rw-r--r-- | fs/btrfs/ioctl.c | 249 | ||||
| -rw-r--r-- | fs/btrfs/ioctl.h | 66 |
2 files changed, 299 insertions, 16 deletions
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index ac2a28f4fa1a..c6044733198d 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -744,16 +744,206 @@ out: return ret; } +static noinline int key_in_sk(struct btrfs_key *key, + struct btrfs_ioctl_search_key *sk) +{ + if (key->objectid < sk->min_objectid) + return 0; + if (key->offset < sk->min_offset) + return 0; + if (key->type < sk->min_type) + return 0; + if (key->objectid > sk->max_objectid) + return 0; + if (key->type > sk->max_type) + return 0; + if (key->offset > sk->max_offset) + return 0; + return 1; +} + +static noinline int copy_to_sk(struct btrfs_root *root, + struct btrfs_path *path, + struct btrfs_key *key, + struct btrfs_ioctl_search_key *sk, + char *buf, + unsigned long *sk_offset, + int *num_found) +{ + u64 found_transid; + struct extent_buffer *leaf; + struct btrfs_ioctl_search_header sh; + unsigned long item_off; + unsigned long item_len; + int nritems; + int i; + int slot; + int found = 0; + int ret = 0; + + leaf = path->nodes[0]; + slot = path->slots[0]; + nritems = btrfs_header_nritems(leaf); + + if (btrfs_header_generation(leaf) > sk->max_transid) { + i = nritems; + goto advance_key; + } + found_transid = btrfs_header_generation(leaf); + + for (i = slot; i < nritems; i++) { + item_off = btrfs_item_ptr_offset(leaf, i); + item_len = btrfs_item_size_nr(leaf, i); + + if (item_len > BTRFS_SEARCH_ARGS_BUFSIZE) + item_len = 0; + + if (sizeof(sh) + item_len + *sk_offset > + BTRFS_SEARCH_ARGS_BUFSIZE) { + ret = 1; + goto overflow; + } + + btrfs_item_key_to_cpu(leaf, key, i); + if (!key_in_sk(key, sk)) + continue; + + sh.objectid = key->objectid; + sh.offset = key->offset; + sh.type = key->type; + sh.len = item_len; + sh.transid = found_transid; + + /* copy search result header */ + memcpy(buf + *sk_offset, &sh, sizeof(sh)); + *sk_offset += sizeof(sh); + + if (item_len) { + char *p = buf + *sk_offset; + /* copy the item */ + read_extent_buffer(leaf, p, + item_off, item_len); + *sk_offset += item_len; + found++; + } + + if (*num_found >= sk->nr_items) + break; + } +advance_key: + if (key->offset < (u64)-1) + key->offset++; + else if (key->type < (u64)-1) + key->type++; + else if (key->objectid < (u64)-1) + key->objectid++; + ret = 0; +overflow: + *num_found += found; + return ret; +} + +static noinline int search_ioctl(struct inode *inode, + struct btrfs_ioctl_search_args *args) +{ + struct btrfs_root *root; + struct btrfs_key key; + struct btrfs_key max_key; + struct btrfs_path *path; + struct btrfs_ioctl_search_key *sk = &args->key; + struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info; + int ret; + int num_found = 0; + unsigned long sk_offset = 0; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + if (sk->tree_id == 0) { + /* search the root of the inode that was passed */ + root = BTRFS_I(inode)->root; + } else { + key.objectid = sk->tree_id; + key.type = BTRFS_ROOT_ITEM_KEY; + key.offset = (u64)-1; + root = btrfs_read_fs_root_no_name(info, &key); + if (IS_ERR(root)) { + printk(KERN_ERR "could not find root %llu\n", + sk->tree_id); + btrfs_free_path(path); + return -ENOENT; + } + } + + key.objectid = sk->min_objectid; + key.type = sk->min_type; + key.offset = sk->min_offset; + + max_key.objectid = sk->max_objectid; + max_key.type = sk->max_type; + max_key.offset = sk->max_offset; + + path->keep_locks = 1; + + while(1) { + ret = btrfs_search_forward(root, &key, &max_key, path, 0, + sk->min_transid); + if (ret != 0) { + if (ret > 0) + ret = 0; + goto err; + } + ret = copy_to_sk(root, path, &key, sk, args->buf, + &sk_offset, &num_found); + btrfs_release_path(root, path); + if (ret || num_found >= sk->nr_items) + break; + + } + ret = 0; +err: + sk->nr_items = num_found; + btrfs_free_path(path); + return ret; +} + +static noinline int btrfs_ioctl_tree_search(struct file *file, + void __user *argp) +{ + struct btrfs_ioctl_search_args *args; + struct inode *inode; + int ret; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + args = kmalloc(sizeof(*args), GFP_KERNEL); + if (!args) + return -ENOMEM; + + if (copy_from_user(args, argp, sizeof(*args))) { + kfree(args); + return -EFAULT; + } + inode = fdentry(file)->d_inode; + ret = search_ioctl(inode, args); + if (ret == 0 && copy_to_user(argp, args, sizeof(*args))) + ret = -EFAULT; + kfree(args); + return ret; +} + /* - Search INODE_REFs to identify path name of 'dirid' directory - in a 'tree_id' tree. and sets path name to 'name'. -*/ + * Search INODE_REFs to identify path name of 'dirid' directory + * in a 'tree_id' tree. and sets path name to 'name'. + */ static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info, u64 tree_id, u64 dirid, char *name) { struct btrfs_root *root; struct btrfs_key key; - char *name_stack, *ptr; + char *ptr; int ret = -1; int slot; int len; @@ -771,13 +961,7 @@ static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info, if (!path) return -ENOMEM; - name_stack = kzalloc(BTRFS_PATH_NAME_MAX+1, GFP_NOFS); - if (!name_stack) { - btrfs_free_path(path); - return -ENOMEM; - } - - ptr = &name_stack[BTRFS_PATH_NAME_MAX]; + ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX]; key.objectid = tree_id; key.type = BTRFS_ROOT_ITEM_KEY; @@ -802,14 +986,16 @@ static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info, btrfs_item_key_to_cpu(l, &key, slot); if (ret > 0 && (key.objectid != dirid || - key.type != BTRFS_INODE_REF_KEY)) + key.type != BTRFS_INODE_REF_KEY)) { + ret = -ENOENT; goto out; + } iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref); len = btrfs_inode_ref_name_len(l, iref); ptr -= len + 1; total_len += len + 1; - if (ptr < name_stack) + if (ptr < name) goto out; *(ptr + len) = '/'; @@ -824,14 +1010,41 @@ static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info, dirid = key.objectid; } - if (ptr < name_stack) + if (ptr < name) goto out; - strncpy(name, ptr, total_len); + memcpy(name, ptr, total_len); name[total_len]='\0'; ret = 0; out: btrfs_free_path(path); - kfree(name_stack); + return ret; +} + +static noinline int btrfs_ioctl_ino_lookup(struct file *file, + void __user *argp) +{ + struct btrfs_ioctl_ino_lookup_args *args; + struct inode *inode; + int ret; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + args = kmalloc(sizeof(*args), GFP_KERNEL); + if (copy_from_user(args, argp, sizeof(*args))) { + kfree(args); + return -EFAULT; + } + inode = fdentry(file)->d_inode; + + ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info, + args->treeid, args->objectid, + args->name); + + if (ret == 0 && copy_to_user(argp, args, sizeof(*args))) + ret = -EFAULT; + + kfree(args); return ret; } @@ -1430,6 +1643,10 @@ long btrfs_ioctl(struct file *file, unsigned int return btrfs_ioctl_trans_start(file); case BTRFS_IOC_TRANS_END: return btrfs_ioctl_trans_end(file); + case BTRFS_IOC_TREE_SEARCH: + return btrfs_ioctl_tree_search(file, argp); + case BTRFS_IOC_INO_LOOKUP: + return btrfs_ioctl_ino_lookup(file, argp); case BTRFS_IOC_SYNC: btrfs_sync_fs(file->f_dentry->d_sb, 1); return 0; diff --git a/fs/btrfs/ioctl.h b/fs/btrfs/ioctl.h index bc49914475eb..79c07b104f91 100644 --- a/fs/btrfs/ioctl.h +++ b/fs/btrfs/ioctl.h @@ -30,6 +30,68 @@ struct btrfs_ioctl_vol_args { char name[BTRFS_PATH_NAME_MAX + 1]; }; +#define BTRFS_INO_LOOKUP_PATH_MAX 4080 +struct btrfs_ioctl_ino_lookup_args { + __u64 treeid; + __u64 objectid; + char name[BTRFS_INO_LOOKUP_PATH_MAX]; +}; + +struct btrfs_ioctl_search_key { + /* which root are we searching. 0 is the tree of tree roots */ + __u64 tree_id; + + /* keys returned will be >= min and <= max */ + __u64 min_objectid; + __u64 max_objectid; + + /* keys returned will be >= min and <= max */ + __u64 min_offset; + __u64 max_offset; + + /* max and min transids to search for */ + __u64 min_transid; + __u64 max_transid; + + /* keys returned will be >= min and <= max */ + __u32 min_type; + __u32 max_type; + + /* + * how many items did userland ask for, and how many are we + * returning + */ + __u32 nr_items; + + /* align to 64 bits */ + __u32 unused; + + /* some extra for later */ + __u64 unused1; + __u64 unused2; + __u64 unused3; + __u64 unused4; +}; + +struct btrfs_ioctl_search_header { + __u64 transid; + __u64 objectid; + __u64 offset; + __u32 type; + __u32 len; +}; + +#define BTRFS_SEARCH_ARGS_BUFSIZE (4096 - sizeof(struct btrfs_ioctl_search_key)) +/* + * the buf is an array of search headers where + * each header is followed by the actual item + * the type field is expanded to 32 bits for alignment + */ +struct btrfs_ioctl_search_args { + struct btrfs_ioctl_search_key key; + char buf[BTRFS_SEARCH_ARGS_BUFSIZE]; +}; + struct btrfs_ioctl_clone_range_args { __s64 src_fd; __u64 src_offset, src_length; @@ -67,4 +129,8 @@ struct btrfs_ioctl_clone_range_args { struct btrfs_ioctl_vol_args) #define BTRFS_IOC_SNAP_DESTROY _IOW(BTRFS_IOCTL_MAGIC, 15, \ struct btrfs_ioctl_vol_args) +#define BTRFS_IOC_TREE_SEARCH _IOWR(BTRFS_IOCTL_MAGIC, 17, \ + struct btrfs_ioctl_search_args) +#define BTRFS_IOC_INO_LOOKUP _IOWR(BTRFS_IOCTL_MAGIC, 18, \ + struct btrfs_ioctl_ino_lookup_args) #endif |