From 54dbc15172375641ef03399e8f911d7165eb90fb Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Sat, 19 Dec 2015 00:55:59 -0800 Subject: [PATCH] vfs: hoist the btrfs deduplication ioctl to the vfs Hoist the btrfs EXTENT_SAME ioctl up to the VFS and make the name more systematic (FIDEDUPERANGE). Signed-off-by: Darrick J. Wong Signed-off-by: Al Viro --- fs/compat_ioctl.c | 1 + fs/ioctl.c | 38 +++++++++++++++ fs/read_write.c | 100 ++++++++++++++++++++++++++++++++++++++++ include/linux/fs.h | 4 ++ include/uapi/linux/fs.h | 30 ++++++++++++ 5 files changed, 173 insertions(+) diff --git a/fs/compat_ioctl.c b/fs/compat_ioctl.c index 70d4b104c08d..eab31e74b9cc 100644 --- a/fs/compat_ioctl.c +++ b/fs/compat_ioctl.c @@ -1582,6 +1582,7 @@ COMPAT_SYSCALL_DEFINE3(ioctl, unsigned int, fd, unsigned int, cmd, case FICLONE: case FICLONERANGE: + case FIDEDUPERANGE: goto do_ioctl; case FIBMAP: diff --git a/fs/ioctl.c b/fs/ioctl.c index 84c6e79829ab..fcdd33b7ec78 100644 --- a/fs/ioctl.c +++ b/fs/ioctl.c @@ -568,6 +568,41 @@ static int ioctl_fsthaw(struct file *filp) return thaw_super(sb); } +static long ioctl_file_dedupe_range(struct file *file, void __user *arg) +{ + struct file_dedupe_range __user *argp = arg; + struct file_dedupe_range *same = NULL; + int ret; + unsigned long size; + u16 count; + + if (get_user(count, &argp->dest_count)) { + ret = -EFAULT; + goto out; + } + + size = offsetof(struct file_dedupe_range __user, info[count]); + + same = memdup_user(argp, size); + if (IS_ERR(same)) { + ret = PTR_ERR(same); + same = NULL; + goto out; + } + + ret = vfs_dedupe_file_range(file, same); + if (ret) + goto out; + + ret = copy_to_user(argp, same, size); + if (ret) + ret = -EFAULT; + +out: + kfree(same); + return ret; +} + /* * When you add any new common ioctls to the switches above and below * please update compat_sys_ioctl() too. @@ -629,6 +664,9 @@ int do_vfs_ioctl(struct file *filp, unsigned int fd, unsigned int cmd, case FICLONERANGE: return ioctl_file_clone_range(filp, argp); + case FIDEDUPERANGE: + return ioctl_file_dedupe_range(filp, argp); + default: if (S_ISREG(inode->i_mode)) error = file_ioctl(filp, cmd, arg); diff --git a/fs/read_write.c b/fs/read_write.c index 60ee26941231..2116e74a83d3 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -1523,3 +1523,103 @@ int vfs_clone_file_range(struct file *file_in, loff_t pos_in, return ret; } EXPORT_SYMBOL(vfs_clone_file_range); + +int vfs_dedupe_file_range(struct file *file, struct file_dedupe_range *same) +{ + struct file_dedupe_range_info *info; + struct inode *src = file_inode(file); + u64 off; + u64 len; + int i; + int ret; + bool is_admin = capable(CAP_SYS_ADMIN); + u16 count = same->dest_count; + struct file *dst_file; + loff_t dst_off; + ssize_t deduped; + + if (!(file->f_mode & FMODE_READ)) + return -EINVAL; + + if (same->reserved1 || same->reserved2) + return -EINVAL; + + off = same->src_offset; + len = same->src_length; + + ret = -EISDIR; + if (S_ISDIR(src->i_mode)) + goto out; + + ret = -EINVAL; + if (!S_ISREG(src->i_mode)) + goto out; + + ret = clone_verify_area(file, off, len, false); + if (ret < 0) + goto out; + ret = 0; + + /* pre-format output fields to sane values */ + for (i = 0; i < count; i++) { + same->info[i].bytes_deduped = 0ULL; + same->info[i].status = FILE_DEDUPE_RANGE_SAME; + } + + for (i = 0, info = same->info; i < count; i++, info++) { + struct inode *dst; + struct fd dst_fd = fdget(info->dest_fd); + + dst_file = dst_fd.file; + if (!dst_file) { + info->status = -EBADF; + goto next_loop; + } + dst = file_inode(dst_file); + + ret = mnt_want_write_file(dst_file); + if (ret) { + info->status = ret; + goto next_loop; + } + + dst_off = info->dest_offset; + ret = clone_verify_area(dst_file, dst_off, len, true); + if (ret < 0) { + info->status = ret; + goto next_file; + } + ret = 0; + + if (info->reserved) { + info->status = -EINVAL; + } else if (!(is_admin || (dst_file->f_mode & FMODE_WRITE))) { + info->status = -EINVAL; + } else if (file->f_path.mnt != dst_file->f_path.mnt) { + info->status = -EXDEV; + } else if (S_ISDIR(dst->i_mode)) { + info->status = -EISDIR; + } else if (dst_file->f_op->dedupe_file_range == NULL) { + info->status = -EINVAL; + } else { + deduped = dst_file->f_op->dedupe_file_range(file, off, + len, dst_file, + info->dest_offset); + if (deduped == -EBADE) + info->status = FILE_DEDUPE_RANGE_DIFFERS; + else if (deduped < 0) + info->status = deduped; + else + info->bytes_deduped += deduped; + } + +next_file: + mnt_drop_write_file(dst_file); +next_loop: + fdput(dst_fd); + } + +out: + return ret; +} +EXPORT_SYMBOL(vfs_dedupe_file_range); diff --git a/include/linux/fs.h b/include/linux/fs.h index 5d987aefcf1e..d71814b81a3c 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1633,6 +1633,8 @@ struct file_operations { loff_t, size_t, unsigned int); int (*clone_file_range)(struct file *, loff_t, struct file *, loff_t, u64); + ssize_t (*dedupe_file_range)(struct file *, u64, u64, struct file *, + u64); }; struct inode_operations { @@ -1688,6 +1690,8 @@ extern ssize_t vfs_copy_file_range(struct file *, loff_t , struct file *, loff_t, size_t, unsigned int); 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(struct file *file, + struct file_dedupe_range *same); struct super_operations { struct inode *(*alloc_inode)(struct super_block *sb); diff --git a/include/uapi/linux/fs.h b/include/uapi/linux/fs.h index cd5db7fb3cb7..b38e647664a0 100644 --- a/include/uapi/linux/fs.h +++ b/include/uapi/linux/fs.h @@ -52,6 +52,35 @@ struct fstrim_range { __u64 minlen; }; +/* extent-same (dedupe) ioctls; these MUST match the btrfs ioctl definitions */ +#define FILE_DEDUPE_RANGE_SAME 0 +#define FILE_DEDUPE_RANGE_DIFFERS 1 + +/* from struct btrfs_ioctl_file_extent_same_info */ +struct file_dedupe_range_info { + __s64 dest_fd; /* in - destination file */ + __u64 dest_offset; /* in - start of extent in destination */ + __u64 bytes_deduped; /* out - total # of bytes we were able + * to dedupe from this file. */ + /* status of this dedupe operation: + * < 0 for error + * == FILE_DEDUPE_RANGE_SAME if dedupe succeeds + * == FILE_DEDUPE_RANGE_DIFFERS if data differs + */ + __s32 status; /* out - see above description */ + __u32 reserved; /* must be zero */ +}; + +/* from struct btrfs_ioctl_file_extent_same_args */ +struct file_dedupe_range { + __u64 src_offset; /* in - start of extent in source */ + __u64 src_length; /* in - length of extent */ + __u16 dest_count; /* in - total elements in info array */ + __u16 reserved1; /* must be zero */ + __u32 reserved2; /* must be zero */ + struct file_dedupe_range_info info[0]; +}; + /* And dynamically-tunable limits and defaults: */ struct files_stat_struct { unsigned long nr_files; /* read only */ @@ -168,6 +197,7 @@ struct inodes_stat_t { #define FITRIM _IOWR('X', 121, struct fstrim_range) /* Trim */ #define FICLONE _IOW(0x94, 9, int) #define FICLONERANGE _IOW(0x94, 13, struct file_clone_range) +#define FIDEDUPERANGE _IOWR(0x94, 54, struct file_dedupe_range) #define FS_IOC_GETFLAGS _IOR('f', 1, long) #define FS_IOC_SETFLAGS _IOW('f', 2, long) -- 2.20.1