diff options
-rw-r--r-- | Documentation/filesystems/porting | 5 | ||||
-rw-r--r-- | Documentation/filesystems/vfs.txt | 22 | ||||
-rw-r--r-- | fs/btrfs/ctree.h | 8 | ||||
-rw-r--r-- | fs/btrfs/file.c | 3 | ||||
-rw-r--r-- | fs/btrfs/ioctl.c | 50 | ||||
-rw-r--r-- | fs/cifs/cifsfs.c | 24 | ||||
-rw-r--r-- | fs/ioctl.c | 10 | ||||
-rw-r--r-- | fs/nfs/nfs4file.c | 12 | ||||
-rw-r--r-- | fs/nfsd/vfs.c | 8 | ||||
-rw-r--r-- | fs/ocfs2/file.c | 93 | ||||
-rw-r--r-- | fs/ocfs2/refcounttree.c | 148 | ||||
-rw-r--r-- | fs/ocfs2/refcounttree.h | 24 | ||||
-rw-r--r-- | fs/overlayfs/copy_up.c | 6 | ||||
-rw-r--r-- | fs/overlayfs/file.c | 43 | ||||
-rw-r--r-- | fs/read_write.c | 405 | ||||
-rw-r--r-- | fs/xfs/xfs_file.c | 82 | ||||
-rw-r--r-- | fs/xfs/xfs_reflink.c | 173 | ||||
-rw-r--r-- | fs/xfs/xfs_reflink.h | 15 | ||||
-rw-r--r-- | include/linux/fs.h | 55 | ||||
-rw-r--r-- | mm/filemap.c | 146 |
20 files changed, 735 insertions, 597 deletions
diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting index 321d74b73937..cf43bc4dbf31 100644 --- a/Documentation/filesystems/porting +++ b/Documentation/filesystems/porting @@ -623,6 +623,11 @@ in your dentry operations instead. On success you get a new struct file sharing the mount/dentry with the original, on failure - ERR_PTR(). -- +[mandatory] + ->clone_file_range() and ->dedupe_file_range have been replaced with + ->remap_file_range(). See Documentation/filesystems/vfs.txt for more + information. +-- [recommended] ->lookup() instances doing an equivalent of if (IS_ERR(inode)) diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt index a6c6a8af48a2..5f71a252e2e0 100644 --- a/Documentation/filesystems/vfs.txt +++ b/Documentation/filesystems/vfs.txt @@ -883,8 +883,9 @@ struct file_operations { unsigned (*mmap_capabilities)(struct file *); #endif ssize_t (*copy_file_range)(struct file *, loff_t, struct file *, loff_t, size_t, unsigned int); - int (*clone_file_range)(struct file *, loff_t, struct file *, loff_t, u64); - int (*dedupe_file_range)(struct file *, loff_t, struct file *, loff_t, u64); + loff_t (*remap_file_range)(struct file *file_in, loff_t pos_in, + struct file *file_out, loff_t pos_out, + loff_t len, unsigned int remap_flags); int (*fadvise)(struct file *, loff_t, loff_t, int); }; @@ -960,11 +961,18 @@ otherwise noted. copy_file_range: called by the copy_file_range(2) system call. - clone_file_range: called by the ioctl(2) system call for FICLONERANGE and - FICLONE commands. - - dedupe_file_range: called by the ioctl(2) system call for FIDEDUPERANGE - command. + remap_file_range: called by the ioctl(2) system call for FICLONERANGE and + FICLONE and FIDEDUPERANGE commands to remap file ranges. An + implementation should remap len bytes at pos_in of the source file into + the dest file at pos_out. Implementations must handle callers passing + in len == 0; this means "remap to the end of the source file". The + return value should the number of bytes remapped, or the usual + negative error code if errors occurred before any bytes were remapped. + The remap_flags parameter accepts REMAP_FILE_* flags. If + REMAP_FILE_DEDUP is set then the implementation must only remap if the + requested file ranges have identical contents. If REMAP_CAN_SHORTEN is + set, the caller is ok with the implementation shortening the request + length to satisfy alignment or EOF requirements (or any other reason). fadvise: possibly called by the fadvise64() system call. diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 68ca41dbbef3..80953528572d 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -3201,9 +3201,6 @@ void btrfs_get_block_group_info(struct list_head *groups_list, struct btrfs_ioctl_space_info *space); void btrfs_update_ioctl_balance_args(struct btrfs_fs_info *fs_info, struct btrfs_ioctl_balance_args *bargs); -int btrfs_dedupe_file_range(struct file *src_file, loff_t src_loff, - struct file *dst_file, loff_t dst_loff, - u64 olen); /* file.c */ int __init btrfs_auto_defrag_init(void); @@ -3233,8 +3230,9 @@ int btrfs_dirty_pages(struct inode *inode, struct page **pages, size_t num_pages, loff_t pos, size_t write_bytes, struct extent_state **cached); int btrfs_fdatawrite_range(struct inode *inode, loff_t start, loff_t end); -int btrfs_clone_file_range(struct file *file_in, loff_t pos_in, - struct file *file_out, loff_t pos_out, u64 len); +loff_t btrfs_remap_file_range(struct file *file_in, loff_t pos_in, + struct file *file_out, loff_t pos_out, + loff_t len, unsigned int remap_flags); /* tree-defrag.c */ int btrfs_defrag_leaves(struct btrfs_trans_handle *trans, diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index 97c7a086f7bd..a3c22e16509b 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -3298,8 +3298,7 @@ const struct file_operations btrfs_file_operations = { #ifdef CONFIG_COMPAT .compat_ioctl = btrfs_compat_ioctl, #endif - .clone_file_range = btrfs_clone_file_range, - .dedupe_file_range = btrfs_dedupe_file_range, + .remap_file_range = btrfs_remap_file_range, }; void __cold btrfs_auto_defrag_exit(void) diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index a990a9045139..3ca6943827ef 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -3629,26 +3629,6 @@ out_unlock: return ret; } -int btrfs_dedupe_file_range(struct file *src_file, loff_t src_loff, - struct file *dst_file, loff_t dst_loff, - u64 olen) -{ - struct inode *src = file_inode(src_file); - struct inode *dst = file_inode(dst_file); - u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize; - - if (WARN_ON_ONCE(bs < PAGE_SIZE)) { - /* - * Btrfs does not support blocksize < page_size. As a - * result, btrfs_cmp_data() won't correctly handle - * this situation without an update. - */ - return -EINVAL; - } - - return btrfs_extent_same(src, src_loff, olen, dst, dst_loff); -} - static int clone_finish_inode_update(struct btrfs_trans_handle *trans, struct inode *inode, u64 endoff, @@ -4350,10 +4330,34 @@ out_unlock: return ret; } -int btrfs_clone_file_range(struct file *src_file, loff_t off, - struct file *dst_file, loff_t destoff, u64 len) +loff_t btrfs_remap_file_range(struct file *src_file, loff_t off, + struct file *dst_file, loff_t destoff, loff_t len, + unsigned int remap_flags) { - return btrfs_clone_files(dst_file, src_file, off, len, destoff); + int ret; + + if (remap_flags & ~(REMAP_FILE_DEDUP | REMAP_FILE_ADVISORY)) + return -EINVAL; + + if (remap_flags & REMAP_FILE_DEDUP) { + struct inode *src = file_inode(src_file); + struct inode *dst = file_inode(dst_file); + u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize; + + if (WARN_ON_ONCE(bs < PAGE_SIZE)) { + /* + * Btrfs does not support blocksize < page_size. As a + * result, btrfs_cmp_data() won't correctly handle + * this situation without an update. + */ + return -EINVAL; + } + + ret = btrfs_extent_same(src, off, len, dst, destoff); + } else { + ret = btrfs_clone_files(dst_file, src_file, off, len, destoff); + } + return ret < 0 ? ret : len; } static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp) diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c index 7de9603c54f1..b7ac09e38159 100644 --- a/fs/cifs/cifsfs.c +++ b/fs/cifs/cifsfs.c @@ -992,8 +992,9 @@ const struct inode_operations cifs_symlink_inode_ops = { .listxattr = cifs_listxattr, }; -static int cifs_clone_file_range(struct file *src_file, loff_t off, - struct file *dst_file, loff_t destoff, u64 len) +static loff_t cifs_remap_file_range(struct file *src_file, loff_t off, + struct file *dst_file, loff_t destoff, loff_t len, + unsigned int remap_flags) { struct inode *src_inode = file_inode(src_file); struct inode *target_inode = file_inode(dst_file); @@ -1003,6 +1004,9 @@ static int cifs_clone_file_range(struct file *src_file, loff_t off, unsigned int xid; int rc; + if (remap_flags & ~REMAP_FILE_ADVISORY) + return -EINVAL; + cifs_dbg(FYI, "clone range\n"); xid = get_xid(); @@ -1042,7 +1046,7 @@ static int cifs_clone_file_range(struct file *src_file, loff_t off, unlock_two_nondirectories(src_inode, target_inode); out: free_xid(xid); - return rc; + return rc < 0 ? rc : len; } ssize_t cifs_file_copychunk_range(unsigned int xid, @@ -1151,7 +1155,7 @@ const struct file_operations cifs_file_ops = { .llseek = cifs_llseek, .unlocked_ioctl = cifs_ioctl, .copy_file_range = cifs_copy_file_range, - .clone_file_range = cifs_clone_file_range, + .remap_file_range = cifs_remap_file_range, .setlease = cifs_setlease, .fallocate = cifs_fallocate, }; @@ -1170,7 +1174,7 @@ const struct file_operations cifs_file_strict_ops = { .llseek = cifs_llseek, .unlocked_ioctl = cifs_ioctl, .copy_file_range = cifs_copy_file_range, - .clone_file_range = cifs_clone_file_range, + .remap_file_range = cifs_remap_file_range, .setlease = cifs_setlease, .fallocate = cifs_fallocate, }; @@ -1189,7 +1193,7 @@ const struct file_operations cifs_file_direct_ops = { .splice_write = iter_file_splice_write, .unlocked_ioctl = cifs_ioctl, .copy_file_range = cifs_copy_file_range, - .clone_file_range = cifs_clone_file_range, + .remap_file_range = cifs_remap_file_range, .llseek = cifs_llseek, .setlease = cifs_setlease, .fallocate = cifs_fallocate, @@ -1208,7 +1212,7 @@ const struct file_operations cifs_file_nobrl_ops = { .llseek = cifs_llseek, .unlocked_ioctl = cifs_ioctl, .copy_file_range = cifs_copy_file_range, - .clone_file_range = cifs_clone_file_range, + .remap_file_range = cifs_remap_file_range, .setlease = cifs_setlease, .fallocate = cifs_fallocate, }; @@ -1226,7 +1230,7 @@ const struct file_operations cifs_file_strict_nobrl_ops = { .llseek = cifs_llseek, .unlocked_ioctl = cifs_ioctl, .copy_file_range = cifs_copy_file_range, - .clone_file_range = cifs_clone_file_range, + .remap_file_range = cifs_remap_file_range, .setlease = cifs_setlease, .fallocate = cifs_fallocate, }; @@ -1244,7 +1248,7 @@ const struct file_operations cifs_file_direct_nobrl_ops = { .splice_write = iter_file_splice_write, .unlocked_ioctl = cifs_ioctl, .copy_file_range = cifs_copy_file_range, - .clone_file_range = cifs_clone_file_range, + .remap_file_range = cifs_remap_file_range, .llseek = cifs_llseek, .setlease = cifs_setlease, .fallocate = cifs_fallocate, @@ -1256,7 +1260,7 @@ const struct file_operations cifs_dir_ops = { .read = generic_read_dir, .unlocked_ioctl = cifs_ioctl, .copy_file_range = cifs_copy_file_range, - .clone_file_range = cifs_clone_file_range, + .remap_file_range = cifs_remap_file_range, .llseek = generic_file_llseek, .fsync = cifs_dir_fsync, }; diff --git a/fs/ioctl.c b/fs/ioctl.c index 0400297c8d72..d64f622cac8b 100644 --- a/fs/ioctl.c +++ b/fs/ioctl.c @@ -223,6 +223,7 @@ static long ioctl_file_clone(struct file *dst_file, unsigned long srcfd, u64 off, u64 olen, u64 destoff) { struct fd src_file = fdget(srcfd); + loff_t cloned; int ret; if (!src_file.file) @@ -230,7 +231,14 @@ static long ioctl_file_clone(struct file *dst_file, unsigned long srcfd, ret = -EXDEV; if (src_file.file->f_path.mnt != dst_file->f_path.mnt) goto fdput; - ret = vfs_clone_file_range(src_file.file, off, dst_file, destoff, olen); + cloned = vfs_clone_file_range(src_file.file, off, dst_file, destoff, + olen, 0); + if (cloned < 0) + ret = cloned; + else if (olen && cloned != olen) + ret = -EINVAL; + else + ret = 0; fdput: fdput(src_file); return ret; diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c index 4288a6ecaf75..46d691ba04bc 100644 --- a/fs/nfs/nfs4file.c +++ b/fs/nfs/nfs4file.c @@ -180,8 +180,9 @@ static long nfs42_fallocate(struct file *filep, int mode, loff_t offset, loff_t return nfs42_proc_allocate(filep, offset, len); } -static int nfs42_clone_file_range(struct file *src_file, loff_t src_off, - struct file *dst_file, loff_t dst_off, u64 count) +static loff_t nfs42_remap_file_range(struct file *src_file, loff_t src_off, + struct file *dst_file, loff_t dst_off, loff_t count, + unsigned int remap_flags) { struct inode *dst_inode = file_inode(dst_file); struct nfs_server *server = NFS_SERVER(dst_inode); @@ -190,6 +191,9 @@ static int nfs42_clone_file_range(struct file *src_file, loff_t src_off, bool same_inode = false; int ret; + if (remap_flags & ~REMAP_FILE_ADVISORY) + return -EINVAL; + /* check alignment w.r.t. clone_blksize */ ret = -EINVAL; if (bs) { @@ -240,7 +244,7 @@ out_unlock: inode_unlock(src_inode); } out: - return ret; + return ret < 0 ? ret : count; } #endif /* CONFIG_NFS_V4_2 */ @@ -262,7 +266,7 @@ const struct file_operations nfs4_file_operations = { .copy_file_range = nfs4_copy_file_range, .llseek = nfs4_file_llseek, .fallocate = nfs42_fallocate, - .clone_file_range = nfs42_clone_file_range, + .remap_file_range = nfs42_remap_file_range, #else .llseek = nfs_file_llseek, #endif diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index fb28be653014..eb67098117b4 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -541,8 +541,12 @@ __be32 nfsd4_set_nfs4_label(struct svc_rqst *rqstp, struct svc_fh *fhp, __be32 nfsd4_clone_file_range(struct file *src, u64 src_pos, struct file *dst, u64 dst_pos, u64 count) { - return nfserrno(vfs_clone_file_range(src, src_pos, dst, dst_pos, - count)); + loff_t cloned; + + cloned = vfs_clone_file_range(src, src_pos, dst, dst_pos, count, 0); + if (count && cloned != count) + cloned = -EINVAL; + return nfserrno(cloned < 0 ? cloned : 0); } ssize_t nfsd_copy_file_range(struct file *src, u64 src_pos, struct file *dst, diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c index 9fa35cb6f6e0..fe570824b991 100644 --- a/fs/ocfs2/file.c +++ b/fs/ocfs2/file.c @@ -2527,24 +2527,79 @@ out: return offset; } -static int ocfs2_file_clone_range(struct file *file_in, - loff_t pos_in, - struct file *file_out, - loff_t pos_out, - u64 len) +static loff_t ocfs2_remap_file_range(struct file *file_in, loff_t pos_in, + struct file *file_out, loff_t pos_out, + loff_t len, unsigned int remap_flags) { - return ocfs2_reflink_remap_range(file_in, pos_in, file_out, pos_out, - len, false); -} + struct inode *inode_in = file_inode(file_in); + struct inode *inode_out = file_inode(file_out); + struct ocfs2_super *osb = OCFS2_SB(inode_in->i_sb); + struct buffer_head *in_bh = NULL, *out_bh = NULL; + bool same_inode = (inode_in == inode_out); + loff_t remapped = 0; + ssize_t ret; -static int ocfs2_file_dedupe_range(struct file *file_in, - loff_t pos_in, - struct file *file_out, - loff_t pos_out, - u64 len) -{ - return ocfs2_reflink_remap_range(file_in, pos_in, file_out, pos_out, - len, true); + if (remap_flags & ~(REMAP_FILE_DEDUP | REMAP_FILE_ADVISORY)) + return -EINVAL; + if (!ocfs2_refcount_tree(osb)) + return -EOPNOTSUPP; + if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb)) + return -EROFS; + + /* Lock both files against IO */ + ret = ocfs2_reflink_inodes_lock(inode_in, &in_bh, inode_out, &out_bh); + if (ret) + return ret; + + /* Check file eligibility and prepare for block sharing. */ + ret = -EINVAL; + if ((OCFS2_I(inode_in)->ip_flags & OCFS2_INODE_SYSTEM_FILE) || + (OCFS2_I(inode_out)->ip_flags & OCFS2_INODE_SYSTEM_FILE)) + goto out_unlock; + + ret = generic_remap_file_range_prep(file_in, pos_in, file_out, pos_out, + &len, remap_flags); + if (ret < 0 || len == 0) + goto out_unlock; + + /* Lock out changes to the allocation maps and remap. */ + down_write(&OCFS2_I(inode_in)->ip_alloc_sem); + if (!same_inode) + down_write_nested(&OCFS2_I(inode_out)->ip_alloc_sem, + SINGLE_DEPTH_NESTING); + + /* Zap any page cache for the destination file's range. */ + truncate_inode_pages_range(&inode_out->i_data, + round_down(pos_out, PAGE_SIZE), + round_up(pos_out + len, PAGE_SIZE) - 1); + + remapped = ocfs2_reflink_remap_blocks(inode_in, in_bh, pos_in, + inode_out, out_bh, pos_out, len); + up_write(&OCFS2_I(inode_in)->ip_alloc_sem); + if (!same_inode) + up_write(&OCFS2_I(inode_out)->ip_alloc_sem); + if (remapped < 0) { + ret = remapped; + mlog_errno(ret); + goto out_unlock; + } + + /* + * Empty the extent map so that we may get the right extent + * record from the disk. + */ + ocfs2_extent_map_trunc(inode_in, 0); + ocfs2_extent_map_trunc(inode_out, 0); + + ret = ocfs2_reflink_update_dest(inode_out, out_bh, pos_out + len); + if (ret) { + mlog_errno(ret); + goto out_unlock; + } + +out_unlock: + ocfs2_reflink_inodes_unlock(inode_in, in_bh, inode_out, out_bh); + return remapped > 0 ? remapped : ret; } const struct inode_operations ocfs2_file_iops = { @@ -2586,8 +2641,7 @@ const struct file_operations ocfs2_fops = { .splice_read = generic_file_splice_read, .splice_write = iter_file_splice_write, .fallocate = ocfs2_fallocate, - .clone_file_range = ocfs2_file_clone_range, - .dedupe_file_range = ocfs2_file_dedupe_range, + .remap_file_range = ocfs2_remap_file_range, }; const struct file_operations ocfs2_dops = { @@ -2633,8 +2687,7 @@ const struct file_operations ocfs2_fops_no_plocks = { .splice_read = generic_file_splice_read, .splice_write = iter_file_splice_write, .fallocate = ocfs2_fallocate, - .clone_file_range = ocfs2_file_clone_range, - .dedupe_file_range = ocfs2_file_dedupe_range, + .remap_file_range = ocfs2_remap_file_range, }; const struct file_operations ocfs2_dops_no_plocks = { diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c index 1114ef02e780..a35259eebc56 100644 --- a/fs/ocfs2/refcounttree.c +++ b/fs/ocfs2/refcounttree.c @@ -4466,9 +4466,9 @@ out: } /* Update destination inode size, if necessary. */ -static int ocfs2_reflink_update_dest(struct inode *dest, - struct buffer_head *d_bh, - loff_t newlen) +int ocfs2_reflink_update_dest(struct inode *dest, + struct buffer_head *d_bh, + loff_t newlen) { handle_t *handle; int ret; @@ -4505,14 +4505,14 @@ out_commit: } /* Remap the range pos_in:len in s_inode to pos_out:len in t_inode. */ -static int ocfs2_reflink_remap_extent(struct inode *s_inode, - struct buffer_head *s_bh, - loff_t pos_in, - struct inode *t_inode, - struct buffer_head *t_bh, - loff_t pos_out, - loff_t len, - struct ocfs2_cached_dealloc_ctxt *dealloc) +static loff_t ocfs2_reflink_remap_extent(struct inode *s_inode, + struct buffer_head *s_bh, + loff_t pos_in, + struct inode *t_inode, + struct buffer_head *t_bh, + loff_t pos_out, + loff_t len, + struct ocfs2_cached_dealloc_ctxt *dealloc) { struct ocfs2_extent_tree s_et; struct ocfs2_extent_tree t_et; @@ -4520,8 +4520,9 @@ static int ocfs2_reflink_remap_extent(struct inode *s_inode, struct buffer_head *ref_root_bh = NULL; struct ocfs2_refcount_tree *ref_tree; struct ocfs2_super *osb; + loff_t remapped_bytes = 0; loff_t pstart, plen; - u32 p_cluster, num_clusters, slast, spos, tpos; + u32 p_cluster, num_clusters, slast, spos, tpos, remapped_clus = 0; unsigned int ext_flags; int ret = 0; @@ -4603,30 +4604,34 @@ static int ocfs2_reflink_remap_extent(struct inode *s_inode, next_loop: spos += num_clusters; tpos += num_clusters; + remapped_clus += num_clusters; } -out: - return ret; + goto out; out_unlock_refcount: ocfs2_unlock_refcount_tree(osb, ref_tree, 1); brelse(ref_root_bh); - return ret; +out: + remapped_bytes = ocfs2_clusters_to_bytes(t_inode->i_sb, remapped_clus); + remapped_bytes = min_t(loff_t, len, remapped_bytes); + + return remapped_bytes > 0 ? remapped_bytes : ret; } /* Set up refcount tree and remap s_inode to t_inode. */ -static int ocfs2_reflink_remap_blocks(struct inode *s_inode, - struct buffer_head *s_bh, - loff_t pos_in, - struct inode *t_inode, - struct buffer_head *t_bh, - loff_t pos_out, - loff_t len) +loff_t ocfs2_reflink_remap_blocks(struct inode *s_inode, + struct buffer_head *s_bh, + loff_t pos_in, + struct inode *t_inode, + struct buffer_head *t_bh, + loff_t pos_out, + loff_t len) { struct ocfs2_cached_dealloc_ctxt dealloc; struct ocfs2_super *osb; struct ocfs2_dinode *dis; struct ocfs2_dinode *dit; - int ret; + loff_t ret; osb = OCFS2_SB(s_inode->i_sb); dis = (struct ocfs2_dinode *)s_bh->b_data; @@ -4698,7 +4703,7 @@ static int ocfs2_reflink_remap_blocks(struct inode *s_inode, /* Actually remap extents now. */ ret = ocfs2_reflink_remap_extent(s_inode, s_bh, pos_in, t_inode, t_bh, pos_out, len, &dealloc); - if (ret) { + if (ret < 0) { mlog_errno(ret); goto out; } @@ -4713,10 +4718,10 @@ out: } /* Lock an inode and grab a bh pointing to the inode. */ -static int ocfs2_reflink_inodes_lock(struct inode *s_inode, - struct buffer_head **bh1, - struct inode *t_inode, - struct buffer_head **bh2) +int ocfs2_reflink_inodes_lock(struct inode *s_inode, + struct buffer_head **bh1, + struct inode *t_inode, + struct buffer_head **bh2) { struct inode *inode1; struct inode *inode2; @@ -4801,10 +4806,10 @@ out_i1: } /* Unlock both inodes and release buffers. */ -static void ocfs2_reflink_inodes_unlock(struct inode *s_inode, - struct buffer_head *s_bh, - struct inode *t_inode, - struct buffer_head *t_bh) +void ocfs2_reflink_inodes_unlock(struct inode *s_inode, + struct buffer_head *s_bh, + struct inode *t_inode, + struct buffer_head *t_bh) { ocfs2_inode_unlock(s_inode, 1); ocfs2_rw_unlock(s_inode, 1); @@ -4816,82 +4821,3 @@ static void ocfs2_reflink_inodes_unlock(struct inode *s_inode, } unlock_two_nondirectories(s_inode, t_inode); } - -/* Link a range of blocks from one file to another. */ -int ocfs2_reflink_remap_range(struct file *file_in, - loff_t pos_in, - struct file *file_out, - loff_t pos_out, - u64 len, - bool is_dedupe) -{ - struct inode *inode_in = file_inode(file_in); - struct inode *inode_out = file_inode(file_out); - struct ocfs2_super *osb = OCFS2_SB(inode_in->i_sb); - struct buffer_head *in_bh = NULL, *out_bh = NULL; - bool same_inode = (inode_in == inode_out); - ssize_t ret; - - if (!ocfs2_refcount_tree(osb)) - return -EOPNOTSUPP; - if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb)) - return -EROFS; - - /* Lock both files against IO */ - ret = ocfs2_reflink_inodes_lock(inode_in, &in_bh, inode_out, &out_bh); - if (ret) - return ret; - - /* Check file eligibility and prepare for block sharing. */ - ret = -EINVAL; - if ((OCFS2_I(inode_in)->ip_flags & OCFS2_INODE_SYSTEM_FILE) || - (OCFS2_I(inode_out)->ip_flags & OCFS2_INODE_SYSTEM_FILE)) - goto out_unlock; - - ret = vfs_clone_file_prep_inodes(inode_in, pos_in, inode_out, pos_out, - &len, is_dedupe); - if (ret <= 0) - goto out_unlock; - - /* Lock out changes to the allocation maps and remap. */ - down_write(&OCFS2_I(inode_in)->ip_alloc_sem); - if (!same_inode) - down_write_nested(&OCFS2_I(inode_out)->ip_alloc_sem, - SINGLE_DEPTH_NESTING); - - ret = ocfs2_reflink_remap_blocks(inode_in, in_bh, pos_in, inode_out, - out_bh, pos_out, len); - - /* Zap any page cache for the destination file's range. */ - if (!ret) - truncate_inode_pages_range(&inode_out->i_data, pos_out, - PAGE_ALIGN(pos_out + len) - 1); - - up_write(&OCFS2_I(inode_in)->ip_alloc_sem); - if (!same_inode) - up_write(&OCFS2_I(inode_out)->ip_alloc_sem); - if (ret) { - mlog_errno(ret); - goto out_unlock; - } - - /* - * Empty the extent map so that we may get the right extent - * record from the disk. - */ - ocfs2_extent_map_trunc(inode_in, 0); - ocfs2_extent_map_trunc(inode_out, 0); - - ret = ocfs2_reflink_update_dest(inode_out, out_bh, pos_out + len); - if (ret) { - mlog_errno(ret); - goto out_unlock; - } - - ocfs2_reflink_inodes_unlock(inode_in, in_bh, inode_out, out_bh); - return 0; - -out_unlock: - ocfs2_reflink_inodes_unlock(inode_in, in_bh, inode_out, out_bh); - return ret; -} diff --git a/fs/ocfs2/refcounttree.h b/fs/ocfs2/refcounttree.h index 4af55bf4b35b..e9e862be4a1e 100644 --- a/fs/ocfs2/refcounttree.h +++ b/fs/ocfs2/refcounttree.h @@ -115,11 +115,23 @@ int ocfs2_reflink_ioctl(struct inode *inode, const char __user *oldname, const char __user *newname, bool preserve); -int ocfs2_reflink_remap_range(struct file *file_in, - loff_t pos_in, - struct file *file_out, - loff_t pos_out, - u64 len, - bool is_dedupe); +loff_t ocfs2_reflink_remap_blocks(struct inode *s_inode, + struct buffer_head *s_bh, + loff_t pos_in, + struct inode *t_inode, + struct buffer_head *t_bh, + loff_t pos_out, + loff_t len); +int ocfs2_reflink_inodes_lock(struct inode *s_inode, + struct buffer_head **bh1, + struct inode *t_inode, + struct buffer_head **bh2); +void ocfs2_reflink_inodes_unlock(struct inode *s_inode, + struct buffer_head *s_bh, + struct inode *t_inode, + struct buffer_head *t_bh); +int ocfs2_reflink_update_dest(struct inode *dest, + struct buffer_head *d_bh, + loff_t newlen); #endif /* OCFS2_REFCOUNTTREE_H */ diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c index d6a3346e2672..9e62dcf06fc4 100644 --- a/fs/overlayfs/copy_up.c +++ b/fs/overlayfs/copy_up.c @@ -125,6 +125,7 @@ static int ovl_copy_up_data(struct path *old, struct path *new, loff_t len) struct file *new_file; loff_t old_pos = 0; loff_t new_pos = 0; + loff_t cloned; int error = 0; if (len == 0) @@ -141,11 +142,10 @@ static int ovl_copy_up_data(struct path *old, struct path *new, loff_t len) } /* Try to use clone_file_range to clone up within the same fs */ - error = do_clone_file_range(old_file, 0, new_file, 0, len); - if (!error) + cloned = do_clone_file_range(old_file, 0, new_file, 0, len, 0); + if (cloned == len) goto out; /* Couldn't clone, so now we try to copy the data */ - error = 0; /* FIXME: copy up sparse files efficiently */ while (len) { diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c index 986313da0c88..84dd957efa24 100644 --- a/fs/overlayfs/file.c +++ b/fs/overlayfs/file.c @@ -434,14 +434,14 @@ enum ovl_copyop { OVL_DEDUPE, }; -static ssize_t ovl_copyfile(struct file *file_in, loff_t pos_in, +static loff_t ovl_copyfile(struct file *file_in, loff_t pos_in, struct file *file_out, loff_t pos_out, - u64 len, unsigned int flags, enum ovl_copyop op) + loff_t len, unsigned int flags, enum ovl_copyop op) { struct inode *inode_out = file_inode(file_out); struct fd real_in, real_out; const struct cred *old_cred; - ssize_t ret; + loff_t ret; ret = ovl_real_fdget(file_out, &real_out); if (ret) @@ -462,12 +462,13 @@ static ssize_t ovl_copyfile(struct file *file_in, loff_t pos_in, case OVL_CLONE: ret = vfs_clone_file_range(real_in.file, pos_in, - real_out.file, pos_out, len); + real_out.file, pos_out, len, flags); break; case OVL_DEDUPE: ret = vfs_dedupe_file_range_one(real_in.file, pos_in, - real_out.file, pos_out, len); + real_out.file, pos_out, len, + flags); break; } revert_creds(old_cred); @@ -489,26 +490,31 @@ static ssize_t ovl_copy_file_range(struct file *file_in, loff_t pos_in, OVL_COPY); } -static int ovl_clone_file_range(struct file *file_in, loff_t pos_in, - struct file *file_out, loff_t pos_out, u64 len) +static loff_t ovl_remap_file_range(struct file *file_in, loff_t pos_in, + struct file *file_out, loff_t pos_out, + loff_t len, unsigned int remap_flags) { - return ovl_copyfile(file_in, pos_in, file_out, pos_out, len, 0, - OVL_CLONE); -} + enum ovl_copyop op; + + if (remap_flags & ~(REMAP_FILE_DEDUP | REMAP_FILE_ADVISORY)) + return -EINVAL; + + if (remap_flags & REMAP_FILE_DEDUP) + op = OVL_DEDUPE; + else + op = OVL_CLONE; -static int ovl_dedupe_file_range(struct file *file_in, loff_t pos_in, - struct file *file_out, loff_t pos_out, u64 len) -{ /* * Don't copy up because of a dedupe request, this wouldn't make sense * most of the time (data would be duplicated instead of deduplicated). */ - if (!ovl_inode_upper(file_inode(file_in)) || - !ovl_inode_upper(file_inode(file_out))) + if (op == OVL_DEDUPE && + (!ovl_inode_upper(file_inode(file_in)) || + !ovl_inode_upper(file_inode(file_out)))) return -EPERM; - return ovl_copyfile(file_in, pos_in, file_out, pos_out, len, 0, - OVL_DEDUPE); + return ovl_copyfile(file_in, pos_in, file_out, pos_out, len, + remap_flags, op); } const struct file_operations ovl_file_operations = { @@ -525,6 +531,5 @@ const struct file_operations ovl_file_operations = { .compat_ioctl = ovl_compat_ioctl, .copy_file_range = ovl_copy_file_range, - .clone_file_range = ovl_clone_file_range, - .dedupe_file_range = ovl_dedupe_file_range, + .remap_file_range = ovl_remap_file_range, }; diff --git a/fs/read_write.c b/fs/read_write.c index 5a2ee488c5d2..bfcb4ced5664 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -1587,11 +1587,15 @@ ssize_t vfs_copy_file_range(struct file *file_in, loff_t pos_in, * Try cloning first, this is supported by more file systems, and * more efficient if both clone and copy are supported (e.g. NFS). */ - if (file_in->f_op->clone_file_range) { - ret = file_in->f_op->clone_file_range(file_in, pos_in, - file_out, pos_out, len); - if (ret == 0) { - ret = len; + if (file_in->f_op->remap_file_range) { + loff_t cloned; + + cloned = file_in->f_op->remap_file_range(file_in, pos_in, + file_out, pos_out, + min_t(loff_t, MAX_RW_COUNT, len), + REMAP_FILE_CAN_SHORTEN); + if (cloned > 0) { + ret = cloned; goto done; } } @@ -1685,11 +1689,12 @@ out2: return ret; } -static int clone_verify_area(struct file *file, loff_t pos, u64 len, bool write) +static int remap_verify_area(struct file *file, loff_t pos, loff_t len, + bool write) { struct inode *inode = file_inode(file); - if (unlikely(pos < 0)) + if (unlikely(pos < 0 || len < 0)) return -EINVAL; if (unlikely((loff_t) (pos + len) < 0)) @@ -1707,22 +1712,150 @@ static int clone_verify_area(struct file *file, loff_t pos, u64 len, bool write) return security_file_permission(file, write ? MAY_WRITE : MAY_READ); } +/* + * Ensure that we don't remap a partial EOF block in the middle of something + * else. Assume that the offsets have already been checked for block + * alignment. + * + * For deduplication we always scale down to the previous block because we + * can't meaningfully compare post-EOF contents. + * + * For clone we only link a partial EOF block above the destination file's EOF. + * + * Shorten the request if possible. + */ +static int generic_remap_check_len(struct inode *inode_in, + struct inode *inode_out, + loff_t pos_out, + loff_t *len, + unsigned int remap_flags) +{ + u64 blkmask = i_blocksize(inode_in) - 1; + loff_t new_len = *len; + + if ((*len & blkmask) == 0) + return 0; + + if ((remap_flags & REMAP_FILE_DEDUP) || + pos_out + *len < i_size_read(inode_out)) + new_len &= ~blkmask; + + if (new_len == *len) + return 0; + + if (remap_flags & REMAP_FILE_CAN_SHORTEN) { + *len = new_len; + return 0; + } + + return (remap_flags & REMAP_FILE_DEDUP) ? -EBADE : -EINVAL; +} + +/* + * Read a page's worth of file data into the page cache. Return the page + * locked. + */ +static struct page *vfs_dedupe_get_page(struct inode *inode, loff_t offset) +{ + struct page *page; + + page = read_mapping_page(inode->i_mapping, offset >> PAGE_SHIFT, NULL); + if (IS_ERR(page)) + return page; + if (!PageUptodate(page)) { + put_page(page); + return ERR_PTR(-EIO); + } + lock_page(page); + return page; +} + +/* + * Compare extents of two files to see if they are the same. + * Caller must have locked both inodes to prevent write races. + */ +static int vfs_dedupe_file_range_compare(struct inode *src, loff_t srcoff, + struct inode *dest, loff_t destoff, + loff_t len, bool *is_same) +{ + loff_t src_poff; + loff_t dest_poff; + void *src_addr; + void *dest_addr; + struct page *src_page; + struct page *dest_page; + loff_t cmp_len; + bool same; + int error; + + error = -EINVAL; + same = true; + while (len) { + src_poff = srcoff & (PAGE_SIZE - 1); + dest_poff = destoff & (PAGE_SIZE - 1); + cmp_len = min(PAGE_SIZE - src_poff, + PAGE_SIZE - dest_poff); + cmp_len = min(cmp_len, len); + if (cmp_len <= 0) + goto out_error; + + src_page = vfs_dedupe_get_page(src, srcoff); + if (IS_ERR(src_page)) { + error = PTR_ERR(src_page); + goto out_error; + } + dest_page = vfs_dedupe_get_page(dest, destoff); + if (IS_ERR(dest_page)) { + error = PTR_ERR(dest_page); + unlock_page(src_page); + put_page(src_page); + goto out_error; + } + src_addr = kmap_atomic(src_page); + dest_addr = kmap_atomic(dest_page); + + flush_dcache_page(src_page); + flush_dcache_page(dest_page); + + if (memcmp(src_addr + src_poff, dest_addr + dest_poff, cmp_len)) + same = false; + + kunmap_atomic(dest_addr); + kunmap_atomic(src_addr); + unlock_page(dest_page); + unlock_page(src_page); + put_page(dest_page); + put_page(src_page); + + if (!same) + break; + + srcoff += cmp_len; + destoff += cmp_len; + len -= cmp_len; + } + + *is_same = same; + return 0; + +out_error: + return error; +} /* * Check that the two inodes are eligible for cloning, the ranges make * sense, and then flush all dirty data. Caller must ensure that the * inodes have been locked against any other modifications. * - * Returns: 0 for "nothing to clone", 1 for "something to clone", or - * the usual negative error code. + * If there's an error, then the usual negative error code is returned. + * Otherwise returns 0 with *len set to the request length. */ -int vfs_clone_file_prep_inodes(struct inode *inode_in, loff_t pos_in, - struct inode *inode_out, loff_t pos_out, - u64 *len, bool is_dedupe) +int generic_remap_file_range_prep(struct file *file_in, loff_t pos_in, + struct file *file_out, loff_t pos_out, + loff_t *len, unsigned int remap_flags) { - loff_t bs = inode_out->i_sb->s_blocksize; - loff_t blen; - loff_t isize; + struct inode *inode_in = file_inode(file_in); + struct inode *inode_out = file_inode(file_out); bool same_inode = (inode_in == inode_out); int ret; @@ -1739,50 +1872,24 @@ int vfs_clone_file_prep_inodes(struct inode *inode_in, loff_t pos_in, if (!S_ISREG(inode_in->i_mode) || !S_ISREG(inode_out->i_mode)) return -EINVAL; - /* Are we going all the way to the end? */ - isize = i_size_read(inode_in); - if (isize == 0) - return 0; - /* Zero length dedupe exits immediately; reflink goes to EOF. */ if (*len == 0) { - if (is_dedupe || pos_in == isize) + loff_t isize = i_size_read(inode_in); + + if ((remap_flags & REMAP_FILE_DEDUP) || pos_in == isize) return 0; if (pos_in > isize) return -EINVAL; *len = isize - pos_in; + if (*len == 0) + return 0; } - /* Ensure offsets don't wrap and the input is inside i_size */ - if (pos_in + *len < pos_in || pos_out + *len < pos_out || - pos_in + *len > isize) - return -EINVAL; - - /* Don't allow dedupe past EOF in the dest file */ - if (is_dedupe) { - loff_t disize; - - disize = i_size_read(inode_out); - if (pos_out >= disize || pos_out + *len > disize) - return -EINVAL; - } - - /* If we're linking to EOF, continue to the block boundary. */ - if (pos_in + *len == isize) - blen = ALIGN(isize, bs) - pos_in; - else - blen = *len; - - /* Only reflink if we're aligned to block boundaries */ - if (!IS_ALIGNED(pos_in, bs) || !IS_ALIGNED(pos_in + blen, bs) || - !IS_ALIGNED(pos_out, bs) || !IS_ALIGNED(pos_out + blen, bs)) - return -EINVAL; - - /* Don't allow overlapped reflink within the same file */ - if (same_inode) { - if (pos_out + blen > pos_in && pos_out < pos_in + blen) - return -EINVAL; - } + /* Check that we don't violate system file offset limits. */ + ret = generic_remap_checks(file_in, pos_in, file_out, pos_out, len, + remap_flags); + if (ret) + return ret; /* Wait for the completion of any pending IOs on both files */ inode_dio_wait(inode_in); @@ -1802,7 +1909,7 @@ int vfs_clone_file_prep_inodes(struct inode *inode_in, loff_t pos_in, /* * Check that the extents are the same. */ - if (is_dedupe) { + if (remap_flags & REMAP_FILE_DEDUP) { bool is_same = false; ret = vfs_dedupe_file_range_compare(inode_in, pos_in, @@ -1813,16 +1920,43 @@ int vfs_clone_file_prep_inodes(struct inode *inode_in, loff_t pos_in, return -EBADE; } - return 1; + ret = generic_remap_check_len(inode_in, inode_out, pos_out, len, + remap_flags); + if (ret) + return ret; + + /* If can't alter the file contents, we're done. */ + if (!(remap_flags & REMAP_FILE_DEDUP)) { + /* Update the timestamps, since we can alter file contents. */ + if (!(file_out->f_mode & FMODE_NOCMTIME)) { + ret = file_update_time(file_out); + if (ret) + return ret; + } + + /* + * Clear the security bits if the process is not being run by + * root. This keeps people from modifying setuid and setgid + * binaries. + */ + ret = file_remove_privs(file_out); + if (ret) + return ret; + } + + return 0; } -EXPORT_SYMBOL(vfs_clone_file_prep_inodes); +EXPORT_SYMBOL(generic_remap_file_range_prep); -int do_clone_file_range(struct file *file_in, loff_t pos_in, - struct file *file_out, loff_t pos_out, u64 len) +loff_t do_clone_file_range(struct file *file_in, loff_t pos_in, + struct file *file_out, loff_t pos_out, + loff_t len, unsigned int remap_flags) { struct inode *inode_in = file_inode(file_in); struct inode *inode_out = file_inode(file_out); - int ret; + loff_t ret; + + WARN_ON_ONCE(remap_flags); if (S_ISDIR(inode_in->i_mode) || S_ISDIR(inode_out->i_mode)) return -EISDIR; @@ -1842,140 +1976,43 @@ int do_clone_file_range(struct file *file_in, loff_t pos_in, (file_out->f_flags & O_APPEND)) return -EBADF; - if (!file_in->f_op->clone_file_range) + if (!file_in->f_op->remap_file_range) return -EOPNOTSUPP; - ret = clone_verify_area(file_in, pos_in, len, false); + ret = remap_verify_area(file_in, pos_in, len, false); if (ret) return ret; - ret = clone_verify_area(file_out, pos_out, len, true); + ret = remap_verify_area(file_out, pos_out, len, true); if (ret) return ret; - if (pos_in + len > i_size_read(inode_in)) - return -EINVAL; - - ret = file_in->f_op->clone_file_range(file_in, pos_in, - file_out, pos_out, len); - if (!ret) { - fsnotify_access(file_in); - fsnotify_modify(file_out); - } + ret = file_in->f_op->remap_file_range(file_in, pos_in, + file_out, pos_out, len, remap_flags); + if (ret < 0) + return ret; + fsnotify_access(file_in); + fsnotify_modify(file_out); return ret; } EXPORT_SYMBOL(do_clone_file_range); -int vfs_clone_file_range(struct file *file_in, loff_t pos_in, - struct file *file_out, loff_t pos_out, u64 len) +loff_t vfs_clone_file_range(struct file *file_in, loff_t pos_in, + struct file *file_out, loff_t pos_out, + loff_t len, unsigned int remap_flags) { - int ret; + loff_t ret; file_start_write(file_out); - ret = do_clone_file_range(file_in, pos_in, file_out, pos_out, len); + ret = do_clone_file_range(file_in, pos_in, file_out, pos_out, len, + remap_flags); file_end_write(file_out); return ret; } EXPORT_SYMBOL(vfs_clone_file_range); -/* - * Read a page's worth of file data into the page cache. Return the page - * locked. - */ -static struct page *vfs_dedupe_get_page(struct inode *inode, loff_t offset) -{ - struct address_space *mapping; - struct page *page; - pgoff_t n; - - n = offset >> PAGE_SHIFT; - mapping = inode->i_mapping; - page = read_mapping_page(mapping, n, NULL); - if (IS_ERR(page)) - return page; - if (!PageUptodate(page)) { - put_page(page); - return ERR_PTR(-EIO); - } - lock_page(page); - return page; -} - -/* - * Compare extents of two files to see if they are the same. - * Caller must have locked both inodes to prevent write races. - */ -int vfs_dedupe_file_range_compare(struct inode *src, loff_t srcoff, - struct inode *dest, loff_t destoff, - loff_t len, bool *is_same) -{ - loff_t src_poff; - loff_t dest_poff; - void *src_addr; - void *dest_addr; - struct page *src_page; - struct page *dest_page; - loff_t cmp_len; - bool same; - int error; - - error = -EINVAL; - same = true; - while (len) { - src_poff = srcoff & (PAGE_SIZE - 1); - dest_poff = destoff & (PAGE_SIZE - 1); - cmp_len = min(PAGE_SIZE - src_poff, - PAGE_SIZE - dest_poff); - cmp_len = min(cmp_len, len); - if (cmp_len <= 0) - goto out_error; - - src_page = vfs_dedupe_get_page(src, srcoff); - if (IS_ERR(src_page)) { - error = PTR_ERR(src_page); - goto out_error; - } - dest_page = vfs_dedupe_get_page(dest, destoff); - if (IS_ERR(dest_page)) { - error = PTR_ERR(dest_page); - unlock_page(src_page); - put_page(src_page); - goto out_error; - } - src_addr = kmap_atomic(src_page); - dest_addr = kmap_atomic(dest_page); - - flush_dcache_page(src_page); - flush_dcache_page(dest_page); - - if (memcmp(src_addr + src_poff, dest_addr + dest_poff, cmp_len)) - same = false; - - kunmap_atomic(dest_addr); - kunmap_atomic(src_addr); - unlock_page(dest_page); - unlock_page(src_page); - put_page(dest_page); - put_page(src_page); - - if (!same) - break; - - srcoff += cmp_len; - destoff += cmp_len; - len -= cmp_len; - } - - *is_same = same; - return 0; - -out_error: - return error; -} -EXPORT_SYMBOL(vfs_dedupe_file_range_compare); - /* Check whether we are allowed to dedupe the destination file */ static bool allow_file_dedupe(struct file *file) { @@ -1990,16 +2027,20 @@ static bool allow_file_dedupe(struct file *file) return false; } -int vfs_dedupe_file_range_one(struct file *src_file, loff_t src_pos, - struct file *dst_file, loff_t dst_pos, u64 len) +loff_t vfs_dedupe_file_range_one(struct file *src_file, loff_t src_pos, + struct file *dst_file, loff_t dst_pos, + loff_t len, unsigned int remap_flags) { - s64 ret; + loff_t ret; + + WARN_ON_ONCE(remap_flags & ~(REMAP_FILE_DEDUP | + REMAP_FILE_CAN_SHORTEN)); ret = mnt_want_write_file(dst_file); if (ret) return ret; - ret = clone_verify_area(dst_file, dst_pos, len, true); + ret = remap_verify_area(dst_file, dst_pos, len, true); if (ret < 0) goto out_drop_write; @@ -2016,11 +2057,16 @@ int vfs_dedupe_file_range_one(struct file *src_file, loff_t src_pos, goto out_drop_write; ret = -EINVAL; - if (!dst_file->f_op->dedupe_file_range) + if (!dst_file->f_op->remap_file_range) goto out_drop_write; - ret = dst_file->f_op->dedupe_file_range(src_file, src_pos, - dst_file, dst_pos, len); + if (len == 0) { + ret = 0; + goto out_drop_write; + } + + ret = dst_file->f_op->remap_file_range(src_file, src_pos, dst_file, + dst_pos, len, remap_flags | REMAP_FILE_DEDUP); out_drop_write: mnt_drop_write_file(dst_file); @@ -2037,7 +2083,7 @@ int vfs_dedupe_file_range(struct file *file, struct file_dedupe_range *same) int i; int ret; u16 count = same->dest_count; - int deduped; + loff_t deduped; if (!(file->f_mode & FMODE_READ)) return -EINVAL; @@ -2056,7 +2102,7 @@ int vfs_dedupe_file_range(struct file *file, struct file_dedupe_range *same) if (!S_ISREG(src->i_mode)) goto out; - ret = clone_verify_area(file, off, len, false); + ret = remap_verify_area(file, off, len, false); if (ret < 0) goto out; ret = 0; @@ -2088,7 +2134,8 @@ int vfs_dedupe_file_range(struct file *file, struct file_dedupe_range *same) } deduped = vfs_dedupe_file_range_one(file, off, dst_file, - info->dest_offset, len); + info->dest_offset, len, + REMAP_FILE_CAN_SHORTEN); if (deduped == -EBADE) info->status = FILE_DEDUPE_RANGE_DIFFERS; else if (deduped < 0) diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index 61a5ad2600e8..53c9ab8fb777 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -919,28 +919,67 @@ out_unlock: return error; } -STATIC int -xfs_file_clone_range( - struct file *file_in, - loff_t pos_in, - struct file *file_out, - loff_t pos_out, - u64 len) -{ - return xfs_reflink_remap_range(file_in, pos_in, file_out, pos_out, - len, false); -} -STATIC int -xfs_file_dedupe_range( - struct file *file_in, - loff_t pos_in, - struct file *file_out, - loff_t pos_out, - u64 len) +loff_t +xfs_file_remap_range( + struct file *file_in, + loff_t pos_in, + struct file *file_out, + loff_t pos_out, + loff_t len, + unsigned int remap_flags) { - return xfs_reflink_remap_range(file_in, pos_in, file_out, pos_out, - len, true); + struct inode *inode_in = file_inode(file_in); + struct xfs_inode *src = XFS_I(inode_in); + struct inode *inode_out = file_inode(file_out); + struct xfs_inode *dest = XFS_I(inode_out); + struct xfs_mount *mp = src->i_mount; + loff_t remapped = 0; + xfs_extlen_t cowextsize; + int ret; + + if (remap_flags & ~(REMAP_FILE_DEDUP | REMAP_FILE_ADVISORY)) + return -EINVAL; + + if (!xfs_sb_version_hasreflink(&mp->m_sb)) + return -EOPNOTSUPP; + + if (XFS_FORCED_SHUTDOWN(mp)) + return -EIO; + + /* Prepare and then clone file data. */ + ret = xfs_reflink_remap_prep(file_in, pos_in, file_out, pos_out, + &len, remap_flags); + if (ret < 0 || len == 0) + return ret; + + trace_xfs_reflink_remap_range(src, pos_in, len, dest, pos_out); + + ret = xfs_reflink_remap_blocks(src, pos_in, dest, pos_out, len, + &remapped); + if (ret) + goto out_unlock; + + /* + * Carry the cowextsize hint from src to dest if we're sharing the + * entire source file to the entire destination file, the source file + * has a cowextsize hint, and the destination file does not. + */ + cowextsize = 0; + if (pos_in == 0 && len == i_size_read(inode_in) && + (src->i_d.di_flags2 & XFS_DIFLAG2_COWEXTSIZE) && + pos_out == 0 && len >= i_size_read(inode_out) && + !(dest->i_d.di_flags2 & XFS_DIFLAG2_COWEXTSIZE)) + cowextsize = src->i_d.di_cowextsize; + + ret = xfs_reflink_update_dest(dest, pos_out + len, cowextsize, + remap_flags); + +out_unlock: + xfs_reflink_remap_unlock(file_in, file_out); + if (ret) + trace_xfs_reflink_remap_range_error(dest, ret, _RET_IP_); + return remapped > 0 ? remapped : ret; } STATIC int @@ -1175,8 +1214,7 @@ const struct file_operations xfs_file_operations = { .fsync = xfs_file_fsync, .get_unmapped_area = thp_get_unmapped_area, .fallocate = xfs_file_fallocate, - .clone_file_range = xfs_file_clone_range, - .dedupe_file_range = xfs_file_dedupe_range, + .remap_file_range = xfs_file_remap_range, }; const struct file_operations xfs_dir_file_operations = { diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c index 8eaeec9d58ed..ecdb086bc23e 100644 --- a/fs/xfs/xfs_reflink.c +++ b/fs/xfs/xfs_reflink.c @@ -913,18 +913,18 @@ out_error: /* * Update destination inode size & cowextsize hint, if necessary. */ -STATIC int +int xfs_reflink_update_dest( struct xfs_inode *dest, xfs_off_t newlen, xfs_extlen_t cowextsize, - bool is_dedupe) + unsigned int remap_flags) { struct xfs_mount *mp = dest->i_mount; struct xfs_trans *tp; int error; - if (is_dedupe && newlen <= i_size_read(VFS_I(dest)) && cowextsize == 0) + if (newlen <= i_size_read(VFS_I(dest)) && cowextsize == 0) return 0; error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ichange, 0, 0, 0, &tp); @@ -945,10 +945,6 @@ xfs_reflink_update_dest( dest->i_d.di_flags2 |= XFS_DIFLAG2_COWEXTSIZE; } - if (!is_dedupe) { - xfs_trans_ichgtime(tp, dest, - XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG); - } xfs_trans_log_inode(tp, dest, XFS_ILOG_CORE); error = xfs_trans_commit(tp); @@ -1112,19 +1108,28 @@ out: /* * Iteratively remap one file's extents (and holes) to another's. */ -STATIC int +int xfs_reflink_remap_blocks( struct xfs_inode *src, - xfs_fileoff_t srcoff, + loff_t pos_in, struct xfs_inode *dest, - xfs_fileoff_t destoff, - xfs_filblks_t len, - xfs_off_t new_isize) + loff_t pos_out, + loff_t remap_len, + loff_t *remapped) { struct xfs_bmbt_irec imap; + xfs_fileoff_t srcoff; + xfs_fileoff_t destoff; + xfs_filblks_t len; + xfs_filblks_t range_len; + xfs_filblks_t remapped_len = 0; + xfs_off_t new_isize = pos_out + remap_len; int nimaps; int error = 0; - xfs_filblks_t range_len; + + destoff = XFS_B_TO_FSBT(src->i_mount, pos_out); + srcoff = XFS_B_TO_FSBT(src->i_mount, pos_in); + len = XFS_B_TO_FSB(src->i_mount, remap_len); /* drange = (destoff, destoff + len); srange = (srcoff, srcoff + len) */ while (len) { @@ -1139,7 +1144,7 @@ xfs_reflink_remap_blocks( error = xfs_bmapi_read(src, srcoff, len, &imap, &nimaps, 0); xfs_iunlock(src, lock_mode); if (error) - goto err; + break; ASSERT(nimaps == 1); trace_xfs_reflink_remap_imap(src, srcoff, len, XFS_IO_OVERWRITE, @@ -1153,23 +1158,24 @@ xfs_reflink_remap_blocks( error = xfs_reflink_remap_extent(dest, &imap, destoff, new_isize); if (error) - goto err; + break; if (fatal_signal_pending(current)) { error = -EINTR; - goto err; + break; } /* Advance drange/srange */ srcoff += range_len; destoff += range_len; len -= range_len; + remapped_len += range_len; } - return 0; - -err: - trace_xfs_reflink_remap_blocks_error(dest, error, _RET_IP_); + if (error) + trace_xfs_reflink_remap_blocks_error(dest, error, _RET_IP_); + *remapped = min_t(loff_t, remap_len, + XFS_FSB_TO_B(src->i_mount, remapped_len)); return error; } @@ -1218,7 +1224,7 @@ retry: } /* Unlock both inodes after they've been prepped for a range clone. */ -STATIC void +void xfs_reflink_remap_unlock( struct file *file_in, struct file *file_out) @@ -1286,21 +1292,20 @@ xfs_reflink_zero_posteof( * stale data in the destination file. Hence we reject these clone attempts with * -EINVAL in this case. */ -STATIC int +int xfs_reflink_remap_prep( struct file *file_in, loff_t pos_in, struct file *file_out, loff_t pos_out, - u64 *len, - bool is_dedupe) + loff_t *len, + unsigned int remap_flags) { struct inode *inode_in = file_inode(file_in); struct xfs_inode *src = XFS_I(inode_in); struct inode *inode_out = file_inode(file_out); struct xfs_inode *dest = XFS_I(inode_out); bool same_inode = (inode_in == inode_out); - u64 blkmask = i_blocksize(inode_in) - 1; ssize_t ret; /* Lock both files against IO */ @@ -1323,29 +1328,11 @@ xfs_reflink_remap_prep( if (IS_DAX(inode_in) || IS_DAX(inode_out)) goto out_unlock; - ret = vfs_clone_file_prep_inodes(inode_in, pos_in, inode_out, pos_out, - len, is_dedupe); - if (ret <= 0) + ret = generic_remap_file_range_prep(file_in, pos_in, file_out, pos_out, + len, remap_flags); + if (ret < 0 || *len == 0) goto out_unlock; - /* - * If the dedupe data matches, chop off the partial EOF block - * from the source file so we don't try to dedupe the partial - * EOF block. - */ - if (is_dedupe) { - *len &= ~blkmask; - } else if (*len & blkmask) { - /* - * The user is attempting to share a partial EOF block, - * if it's inside the destination EOF then reject it. - */ - if (pos_out + *len < i_size_read(inode_out)) { - ret = -EINVAL; - goto out_unlock; - } - } - /* Attach dquots to dest inode before changing block map */ ret = xfs_qm_dqattach(dest); if (ret) @@ -1365,31 +1352,9 @@ xfs_reflink_remap_prep( goto out_unlock; /* Zap any page cache for the destination file's range. */ - truncate_inode_pages_range(&inode_out->i_data, pos_out, - PAGE_ALIGN(pos_out + *len) - 1); - - /* If we're altering the file contents... */ - if (!is_dedupe) { - /* - * ...update the timestamps (which will grab the ilock again - * from xfs_fs_dirty_inode, so we have to call it before we - * take the ilock). - */ - if (!(file_out->f_mode & FMODE_NOCMTIME)) { - ret = file_update_time(file_out); - if (ret) - goto out_unlock; - } - - /* - * ...clear the security bits if the process is not being run - * by root. This keeps people from modifying setuid and setgid - * binaries. - */ - ret = file_remove_privs(file_out); - if (ret) - goto out_unlock; - } + truncate_inode_pages_range(&inode_out->i_data, + round_down(pos_out, PAGE_SIZE), + round_up(pos_out + *len, PAGE_SIZE) - 1); return 1; out_unlock: @@ -1398,72 +1363,6 @@ out_unlock: } /* - * Link a range of blocks from one file to another. - */ -int -xfs_reflink_remap_range( - struct file *file_in, - loff_t pos_in, - struct file *file_out, - loff_t pos_out, - u64 len, - bool is_dedupe) -{ - struct inode *inode_in = file_inode(file_in); - struct xfs_inode *src = XFS_I(inode_in); - struct inode *inode_out = file_inode(file_out); - struct xfs_inode *dest = XFS_I(inode_out); - struct xfs_mount *mp = src->i_mount; - xfs_fileoff_t sfsbno, dfsbno; - xfs_filblks_t fsblen; - xfs_extlen_t cowextsize; - ssize_t ret; - - if (!xfs_sb_version_hasreflink(&mp->m_sb)) - return -EOPNOTSUPP; - - if (XFS_FORCED_SHUTDOWN(mp)) - return -EIO; - - /* Prepare and then clone file data. */ - ret = xfs_reflink_remap_prep(file_in, pos_in, file_out, pos_out, - &len, is_dedupe); - if (ret <= 0) - return ret; - - trace_xfs_reflink_remap_range(src, pos_in, len, dest, pos_out); - - dfsbno = XFS_B_TO_FSBT(mp, pos_out); - sfsbno = XFS_B_TO_FSBT(mp, pos_in); - fsblen = XFS_B_TO_FSB(mp, len); - ret = xfs_reflink_remap_blocks(src, sfsbno, dest, dfsbno, fsblen, - pos_out + len); - if (ret) - goto out_unlock; - - /* - * Carry the cowextsize hint from src to dest if we're sharing the - * entire source file to the entire destination file, the source file - * has a cowextsize hint, and the destination file does not. - */ - cowextsize = 0; - if (pos_in == 0 && len == i_size_read(inode_in) && - (src->i_d.di_flags2 & XFS_DIFLAG2_COWEXTSIZE) && - pos_out == 0 && len >= i_size_read(inode_out) && - !(dest->i_d.di_flags2 & XFS_DIFLAG2_COWEXTSIZE)) - cowextsize = src->i_d.di_cowextsize; - - ret = xfs_reflink_update_dest(dest, pos_out + len, cowextsize, - is_dedupe); - -out_unlock: - xfs_reflink_remap_unlock(file_in, file_out); - if (ret) - trace_xfs_reflink_remap_range_error(dest, ret, _RET_IP_); - return ret; -} - -/* * The user wants to preemptively CoW all shared blocks in this file, * which enables us to turn off the reflink flag. Iterate all * extents which are not prealloc/delalloc to see which ranges are diff --git a/fs/xfs/xfs_reflink.h b/fs/xfs/xfs_reflink.h index 7f47202b5639..6d73daef1f13 100644 --- a/fs/xfs/xfs_reflink.h +++ b/fs/xfs/xfs_reflink.h @@ -27,13 +27,24 @@ extern int xfs_reflink_cancel_cow_range(struct xfs_inode *ip, xfs_off_t offset, extern int xfs_reflink_end_cow(struct xfs_inode *ip, xfs_off_t offset, xfs_off_t count); extern int xfs_reflink_recover_cow(struct xfs_mount *mp); -extern int xfs_reflink_remap_range(struct file *file_in, loff_t pos_in, - struct file *file_out, loff_t pos_out, u64 len, bool is_dedupe); +extern loff_t xfs_reflink_remap_range(struct file *file_in, loff_t pos_in, + struct file *file_out, loff_t pos_out, loff_t len, + unsigned int remap_flags); extern int xfs_reflink_inode_has_shared_extents(struct xfs_trans *tp, struct xfs_inode *ip, bool *has_shared); extern int xfs_reflink_clear_inode_flag(struct xfs_inode *ip, struct xfs_trans **tpp); extern int xfs_reflink_unshare(struct xfs_inode *ip, xfs_off_t offset, xfs_off_t len); +extern int xfs_reflink_remap_prep(struct file *file_in, loff_t pos_in, + struct file *file_out, loff_t pos_out, loff_t *len, + unsigned int remap_flags); +extern int xfs_reflink_remap_blocks(struct xfs_inode *src, loff_t pos_in, + struct xfs_inode *dest, loff_t pos_out, loff_t remap_len, + loff_t *remapped); +extern int xfs_reflink_update_dest(struct xfs_inode *dest, xfs_off_t newlen, + xfs_extlen_t cowextsize, unsigned int remap_flags); +extern void xfs_reflink_remap_unlock(struct file *file_in, + struct file *file_out); #endif /* __XFS_REFLINK_H */ diff --git a/include/linux/fs.h b/include/linux/fs.h index 8252df30b9a1..c95c0807471f 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1752,6 +1752,25 @@ struct block_device_operations; #define NOMMU_VMFLAGS \ (NOMMU_MAP_READ | NOMMU_MAP_WRITE | NOMMU_MAP_EXEC) +/* + * These flags control the behavior of the remap_file_range function pointer. + * If it is called with len == 0 that means "remap to end of source file". + * See Documentation/filesystems/vfs.txt for more details about this call. + * + * REMAP_FILE_DEDUP: only remap if contents identical (i.e. deduplicate) + * REMAP_FILE_CAN_SHORTEN: caller can handle a shortened request + */ +#define REMAP_FILE_DEDUP (1 << 0) +#define REMAP_FILE_CAN_SHORTEN (1 << 1) + +/* + * These flags signal that the caller is ok with altering various aspects of + * the behavior of the remap operation. The changes must be made by the + * implementation; the vfs remap helper functions can take advantage of them. + * Flags in this category exist to preserve the quirky behavior of the hoisted + * btrfs clone/dedupe ioctls. + */ +#define REMAP_FILE_ADVISORY (REMAP_FILE_CAN_SHORTEN) struct iov_iter; @@ -1790,10 +1809,9 @@ struct file_operations { #endif ssize_t (*copy_file_range)(struct file *, loff_t, struct file *, loff_t, size_t, unsigned int); - int (*clone_file_range)(struct file *, loff_t, struct file *, loff_t, - u64); - int (*dedupe_file_range)(struct file *, loff_t, struct file *, loff_t, - u64); + loff_t (*remap_file_range)(struct file *file_in, loff_t pos_in, + struct file *file_out, loff_t pos_out, + loff_t len, unsigned int remap_flags); int (*fadvise)(struct file *, loff_t, loff_t, int); } __randomize_layout; @@ -1856,21 +1874,21 @@ extern ssize_t vfs_readv(struct file *, const struct iovec __user *, unsigned long, loff_t *, rwf_t); extern ssize_t vfs_copy_file_range(struct file *, loff_t , struct file *, loff_t, size_t, unsigned int); -extern int vfs_clone_file_prep_inodes(struct inode *inode_in, loff_t pos_in, - struct inode *inode_out, loff_t pos_out, - u64 *len, bool is_dedupe); -extern int do_clone_file_range(struct file *file_in, loff_t pos_in, - struct file *file_out, loff_t pos_out, u64 len); -extern int vfs_clone_file_range(struct file *file_in, loff_t pos_in, - struct file *file_out, loff_t pos_out, u64 len); -extern int vfs_dedupe_file_range_compare(struct inode *src, loff_t srcoff, - struct inode *dest, loff_t destoff, - loff_t len, bool *is_same); +extern int generic_remap_file_range_prep(struct file *file_in, loff_t pos_in, + struct file *file_out, loff_t pos_out, + loff_t *count, + unsigned int remap_flags); +extern loff_t do_clone_file_range(struct file *file_in, loff_t pos_in, + struct file *file_out, loff_t pos_out, + loff_t len, unsigned int remap_flags); +extern loff_t vfs_clone_file_range(struct file *file_in, loff_t pos_in, + struct file *file_out, loff_t pos_out, + loff_t len, unsigned int remap_flags); extern int vfs_dedupe_file_range(struct file *file, struct file_dedupe_range *same); -extern int vfs_dedupe_file_range_one(struct file *src_file, loff_t src_pos, - struct file *dst_file, loff_t dst_pos, - u64 len); +extern loff_t vfs_dedupe_file_range_one(struct file *src_file, loff_t src_pos, + struct file *dst_file, loff_t dst_pos, + loff_t len, unsigned int remap_flags); struct super_operations { @@ -2998,6 +3016,9 @@ extern int sb_min_blocksize(struct super_block *, int); extern int generic_file_mmap(struct file *, struct vm_area_struct *); extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *); extern ssize_t generic_write_checks(struct kiocb *, struct iov_iter *); +extern int generic_remap_checks(struct file *file_in, loff_t pos_in, + struct file *file_out, loff_t pos_out, + loff_t *count, unsigned int remap_flags); extern ssize_t generic_file_read_iter(struct kiocb *, struct iov_iter *); extern ssize_t __generic_file_write_iter(struct kiocb *, struct iov_iter *); extern ssize_t generic_file_write_iter(struct kiocb *, struct iov_iter *); diff --git a/mm/filemap.c b/mm/filemap.c index 1fe6c4c37a35..81adec8ee02c 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -2825,6 +2825,42 @@ struct page *read_cache_page_gfp(struct address_space *mapping, EXPORT_SYMBOL(read_cache_page_gfp); /* + * Don't operate on ranges the page cache doesn't support, and don't exceed the + * LFS limits. If pos is under the limit it becomes a short access. If it + * exceeds the limit we return -EFBIG. + */ +static int generic_access_check_limits(struct file *file, loff_t pos, + loff_t *count) +{ + struct inode *inode = file->f_mapping->host; + loff_t max_size = inode->i_sb->s_maxbytes; + + if (!(file->f_flags & O_LARGEFILE)) + max_size = MAX_NON_LFS; + + if (unlikely(pos >= max_size)) + return -EFBIG; + *count = min(*count, max_size - pos); + return 0; +} + +static int generic_write_check_limits(struct file *file, loff_t pos, + loff_t *count) +{ + loff_t limit = rlimit(RLIMIT_FSIZE); + + if (limit != RLIM_INFINITY) { + if (pos >= limit) { + send_sig(SIGXFSZ, current, 0); + return -EFBIG; + } + *count = min(*count, limit - pos); + } + + return generic_access_check_limits(file, pos, count); +} + +/* * Performs necessary checks before doing a write * * Can adjust writing position or amount of bytes to write. @@ -2835,8 +2871,8 @@ inline ssize_t generic_write_checks(struct kiocb *iocb, struct iov_iter *from) { struct file *file = iocb->ki_filp; struct inode *inode = file->f_mapping->host; - unsigned long limit = rlimit(RLIMIT_FSIZE); - loff_t pos; + loff_t count; + int ret; if (!iov_iter_count(from)) return 0; @@ -2845,43 +2881,99 @@ inline ssize_t generic_write_checks(struct kiocb *iocb, struct iov_iter *from) if (iocb->ki_flags & IOCB_APPEND) iocb->ki_pos = i_size_read(inode); - pos = iocb->ki_pos; - if ((iocb->ki_flags & IOCB_NOWAIT) && !(iocb->ki_flags & IOCB_DIRECT)) return -EINVAL; - if (limit != RLIM_INFINITY) { - if (iocb->ki_pos >= limit) { - send_sig(SIGXFSZ, current, 0); - return -EFBIG; - } - iov_iter_truncate(from, limit - (unsigned long)pos); - } + count = iov_iter_count(from); + ret = generic_write_check_limits(file, iocb->ki_pos, &count); + if (ret) + return ret; + + iov_iter_truncate(from, count); + return iov_iter_count(from); +} +EXPORT_SYMBOL(generic_write_checks); + +/* + * Performs necessary checks before doing a clone. + * + * Can adjust amount of bytes to clone. + * Returns appropriate error code that caller should return or + * zero in case the clone should be allowed. + */ +int generic_remap_checks(struct file *file_in, loff_t pos_in, + struct file *file_out, loff_t pos_out, + loff_t *req_count, unsigned int remap_flags) +{ + struct inode *inode_in = file_in->f_mapping->host; + struct inode *inode_out = file_out->f_mapping->host; + uint64_t count = *req_count; + uint64_t bcount; + loff_t size_in, size_out; + loff_t bs = inode_out->i_sb->s_blocksize; + int ret; + + /* The start of both ranges must be aligned to an fs block. */ + if (!IS_ALIGNED(pos_in, bs) || !IS_ALIGNED(pos_out, bs)) + return -EINVAL; + + /* Ensure offsets don't wrap. */ + if (pos_in + count < pos_in || pos_out + count < pos_out) + return -EINVAL; + + size_in = i_size_read(inode_in); + size_out = i_size_read(inode_out); + + /* Dedupe requires both ranges to be within EOF. */ + if ((remap_flags & REMAP_FILE_DEDUP) && + (pos_in >= size_in || pos_in + count > size_in || + pos_out >= size_out || pos_out + count > size_out)) + return -EINVAL; + + /* Ensure the infile range is within the infile. */ + if (pos_in >= size_in) + return -EINVAL; + count = min(count, size_in - (uint64_t)pos_in); + + ret = generic_access_check_limits(file_in, pos_in, &count); + if (ret) + return ret; + + ret = generic_write_check_limits(file_out, pos_out, &count); + if (ret) + return ret; /* - * LFS rule + * If the user wanted us to link to the infile's EOF, round up to the + * next block boundary for this check. + * + * Otherwise, make sure the count is also block-aligned, having + * already confirmed the starting offsets' block alignment. */ - if (unlikely(pos + iov_iter_count(from) > MAX_NON_LFS && - !(file->f_flags & O_LARGEFILE))) { - if (pos >= MAX_NON_LFS) - return -EFBIG; - iov_iter_truncate(from, MAX_NON_LFS - (unsigned long)pos); + if (pos_in + count == size_in) { + bcount = ALIGN(size_in, bs) - pos_in; + } else { + if (!IS_ALIGNED(count, bs)) + count = ALIGN_DOWN(count, bs); + bcount = count; } + /* Don't allow overlapped cloning within the same file. */ + if (inode_in == inode_out && + pos_out + bcount > pos_in && + pos_out < pos_in + bcount) + return -EINVAL; + /* - * Are we about to exceed the fs block limit ? - * - * If we have written data it becomes a short write. If we have - * exceeded without writing data we send a signal and return EFBIG. - * Linus frestrict idea will clean these up nicely.. + * We shortened the request but the caller can't deal with that, so + * bounce the request back to userspace. */ - if (unlikely(pos >= inode->i_sb->s_maxbytes)) - return -EFBIG; + if (*req_count != count && !(remap_flags & REMAP_FILE_CAN_SHORTEN)) + return -EINVAL; - iov_iter_truncate(from, inode->i_sb->s_maxbytes - pos); - return iov_iter_count(from); + *req_count = count; + return 0; } -EXPORT_SYMBOL(generic_write_checks); int pagecache_write_begin(struct file *file, struct address_space *mapping, loff_t pos, unsigned len, unsigned flags, |