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 <darrick.wong@oracle.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Darrick J. Wong 2015-12-19 00:55:59 -08:00 коммит произвёл Al Viro
Родитель d79bdd52d8
Коммит 54dbc15172
5 изменённых файлов: 173 добавлений и 0 удалений

Просмотреть файл

@ -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:

Просмотреть файл

@ -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);

Просмотреть файл

@ -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);

Просмотреть файл

@ -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);

Просмотреть файл

@ -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)