diff options
Diffstat (limited to 'fs/btrfs/send.c')
-rw-r--r-- | fs/btrfs/send.c | 152 |
1 files changed, 151 insertions, 1 deletions
diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c index ca15d65a2070..ad570c3b6a0b 100644 --- a/fs/btrfs/send.c +++ b/fs/btrfs/send.c @@ -35,6 +35,7 @@ #include "btrfs_inode.h" #include "transaction.h" #include "compression.h" +#include "xattr.h" /* * Maximum number of references an extent can have in order for us to attempt to @@ -3820,6 +3821,72 @@ static int update_ref_path(struct send_ctx *sctx, struct recorded_ref *ref) } /* + * When processing the new references for an inode we may orphanize an existing + * directory inode because its old name conflicts with one of the new references + * of the current inode. Later, when processing another new reference of our + * inode, we might need to orphanize another inode, but the path we have in the + * reference reflects the pre-orphanization name of the directory we previously + * orphanized. For example: + * + * parent snapshot looks like: + * + * . (ino 256) + * |----- f1 (ino 257) + * |----- f2 (ino 258) + * |----- d1/ (ino 259) + * |----- d2/ (ino 260) + * + * send snapshot looks like: + * + * . (ino 256) + * |----- d1 (ino 258) + * |----- f2/ (ino 259) + * |----- f2_link/ (ino 260) + * | |----- f1 (ino 257) + * | + * |----- d2 (ino 258) + * + * When processing inode 257 we compute the name for inode 259 as "d1", and we + * cache it in the name cache. Later when we start processing inode 258, when + * collecting all its new references we set a full path of "d1/d2" for its new + * reference with name "d2". When we start processing the new references we + * start by processing the new reference with name "d1", and this results in + * orphanizing inode 259, since its old reference causes a conflict. Then we + * move on the next new reference, with name "d2", and we find out we must + * orphanize inode 260, as its old reference conflicts with ours - but for the + * orphanization we use a source path corresponding to the path we stored in the + * new reference, which is "d1/d2" and not "o259-6-0/d2" - this makes the + * receiver fail since the path component "d1/" no longer exists, it was renamed + * to "o259-6-0/" when processing the previous new reference. So in this case we + * must recompute the path in the new reference and use it for the new + * orphanization operation. + */ +static int refresh_ref_path(struct send_ctx *sctx, struct recorded_ref *ref) +{ + char *name; + int ret; + + name = kmemdup(ref->name, ref->name_len, GFP_KERNEL); + if (!name) + return -ENOMEM; + + fs_path_reset(ref->full_path); + ret = get_cur_path(sctx, ref->dir, ref->dir_gen, ref->full_path); + if (ret < 0) + goto out; + + ret = fs_path_add(ref->full_path, name, ref->name_len); + if (ret < 0) + goto out; + + /* Update the reference's base name pointer. */ + set_ref_path(ref, ref->full_path); +out: + kfree(name); + return ret; +} + +/* * This does all the move/link/unlink/rmdir magic. */ static int process_recorded_refs(struct send_ctx *sctx, int *pending_move) @@ -3949,6 +4016,12 @@ static int process_recorded_refs(struct send_ctx *sctx, int *pending_move) struct name_cache_entry *nce; struct waiting_dir_move *wdm; + if (orphanized_dir) { + ret = refresh_ref_path(sctx, cur); + if (ret < 0) + goto out; + } + ret = orphanize_inode(sctx, ow_inode, ow_gen, cur->full_path); if (ret < 0) @@ -4005,6 +4078,17 @@ static int process_recorded_refs(struct send_ctx *sctx, int *pending_move) if (ret < 0) goto out; } else { + /* + * If we previously orphanized a directory that + * collided with a new reference that we already + * processed, recompute the current path because + * that directory may be part of the path. + */ + if (orphanized_dir) { + ret = refresh_ref_path(sctx, cur); + if (ret < 0) + goto out; + } ret = send_unlink(sctx, cur->full_path); if (ret < 0) goto out; @@ -4554,6 +4638,10 @@ static int __process_new_xattr(int num, struct btrfs_key *di_key, struct fs_path *p; struct posix_acl_xattr_header dummy_acl; + /* Capabilities are emitted by finish_inode_if_needed */ + if (!strncmp(name, XATTR_NAME_CAPS, name_len)) + return 0; + p = fs_path_alloc(); if (!p) return -ENOMEM; @@ -5096,6 +5184,64 @@ static int send_extent_data(struct send_ctx *sctx, return 0; } +/* + * Search for a capability xattr related to sctx->cur_ino. If the capability is + * found, call send_set_xattr function to emit it. + * + * Return 0 if there isn't a capability, or when the capability was emitted + * successfully, or < 0 if an error occurred. + */ +static int send_capabilities(struct send_ctx *sctx) +{ + struct fs_path *fspath = NULL; + struct btrfs_path *path; + struct btrfs_dir_item *di; + struct extent_buffer *leaf; + unsigned long data_ptr; + char *buf = NULL; + int buf_len; + int ret = 0; + + path = alloc_path_for_send(); + if (!path) + return -ENOMEM; + + di = btrfs_lookup_xattr(NULL, sctx->send_root, path, sctx->cur_ino, + XATTR_NAME_CAPS, strlen(XATTR_NAME_CAPS), 0); + if (!di) { + /* There is no xattr for this inode */ + goto out; + } else if (IS_ERR(di)) { + ret = PTR_ERR(di); + goto out; + } + + leaf = path->nodes[0]; + buf_len = btrfs_dir_data_len(leaf, di); + + fspath = fs_path_alloc(); + buf = kmalloc(buf_len, GFP_KERNEL); + if (!fspath || !buf) { + ret = -ENOMEM; + goto out; + } + + ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen, fspath); + if (ret < 0) + goto out; + + data_ptr = (unsigned long)(di + 1) + btrfs_dir_name_len(leaf, di); + read_extent_buffer(leaf, buf, data_ptr, buf_len); + + ret = send_set_xattr(sctx, fspath, XATTR_NAME_CAPS, + strlen(XATTR_NAME_CAPS), buf, buf_len); +out: + kfree(buf); + fs_path_free(fspath); + btrfs_free_path(path); + return ret; +} + static int clone_range(struct send_ctx *sctx, struct clone_root *clone_root, const u64 disk_byte, @@ -5907,6 +6053,10 @@ static int finish_inode_if_needed(struct send_ctx *sctx, int at_end) goto out; } + ret = send_capabilities(sctx); + if (ret < 0) + goto out; + /* * If other directory inodes depended on our current directory * inode's move/rename, now do their move/rename operations. @@ -6562,7 +6712,7 @@ long btrfs_ioctl_send(struct file *mnt_file, void __user *arg_) alloc_size = sizeof(struct clone_root) * (arg->clone_sources_count + 1); - sctx->clone_roots = kzalloc(alloc_size, GFP_KERNEL); + sctx->clone_roots = kvzalloc(alloc_size, GFP_KERNEL); if (!sctx->clone_roots) { ret = -ENOMEM; goto out; |