[PATCH v2 09/29] vfs: combine the clone and dedupe into a single remap_file_range

Darrick J. Wong
2018-10-19T02:59:42Z

Combine the clone_file_range and dedupe_file_range operations into a
single remap_file_range file operation dispatch since they're
fundamentally the same operation. The differences between the two can
be made in the prep functions.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
v2: documentation updates requested by Al Viro
---
Documentation/filesystems/porting | 5 ++++
Documentation/filesystems/vfs.txt | 20 +++++++++++-----
fs/btrfs/ctree.h | 8 ++-----
fs/btrfs/file.c | 3 +-
fs/btrfs/ioctl.c | 45 +++++++++++++++++++------------------
fs/cifs/cifsfs.c | 22 +++++++++++-------
fs/nfs/nfs4file.c | 10 ++++++--
fs/ocfs2/file.c | 24 +++++++-------------
fs/overlayfs/file.c | 30 ++++++++++++++-----------
fs/read_write.c | 18 +++++++--------
fs/xfs/xfs_file.c | 23 ++++++-------------
include/linux/fs.h | 25 +++++++++++++++++----
12 files changed, 127 insertions(+), 106 deletions(-)

diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting
index 7b7b845c490a..e6d4466268dd 100644
--- a/Documentation/filesystems/porting
+++ b/Documentation/filesystems/porting
@@ -622,3 +622,8 @@ in your dentry operations instead.
alloc_file_clone(file, flags, ops) does not affect any caller's references.
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.
diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt
index a6c6a8af48a2..6f5babfee27b 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);
+ int (*remap_file_range)(struct file *file_in, loff_t pos_in,
+ struct file *file_out, loff_t pos_out,
+ u64 len, unsigned int remap_flags);
int (*fadvise)(struct file *, loff_t, loff_t, int);
};

@@ -960,11 +961,16 @@ 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 be zero if all bytes were remapped, or the usual
+ negative error code if the remapping did not succeed completely.
+ 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.

fadvise: possibly called by the fadvise64() system call.

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 2cddfe7806a4..124a05662fc2 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -3218,9 +3218,6 @@ 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);
@@ -3250,8 +3247,9 @@ 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);
+int btrfs_remap_file_range(struct file *file_in, loff_t pos_in,
+ struct file *file_out, loff_t pos_out, u64 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 2be00e873e92..9a963f061393 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -3269,8 +3269,7 @@ 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 d60b6caf09e8..bfd99c66723e 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -3627,26 +3627,6 @@ static int btrfs_extent_same(struct inode *src, u64 loff, u64 olen,
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,
@@ -4348,9 +4328,30 @@ static noinline int btrfs_clone_files(struct file *file, struct file *file_src,
return ret;
}

-int btrfs_clone_file_range(struct file *src_file, loff_t off,
- struct file *dst_file, loff_t destoff, u64 len)
+int btrfs_remap_file_range(struct file *src_file, loff_t off,
+ struct file *dst_file, loff_t destoff, u64 len,
+ unsigned int remap_flags)
{
+ 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;
+ }
+
+ return btrfs_extent_same(src, off, len, dst, destoff);
+ }
+
return btrfs_clone_files(dst_file, src_file, off, len, destoff);
}

diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 7065426b3280..e8144d0dcde2 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -975,8 +975,9 @@ 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 int cifs_remap_file_range(struct file *src_file, loff_t off,
+ struct file *dst_file, loff_t destoff, u64 len,
+ unsigned int remap_flags)
{
struct inode *src_inode = file_inode(src_file);
struct inode *target_inode = file_inode(dst_file);
@@ -986,6 +987,9 @@ 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();
@@ -1134,7 +1138,7 @@ 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,
};
@@ -1153,7 +1157,7 @@ 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,
};
@@ -1172,7 +1176,7 @@ 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,
@@ -1191,7 +1195,7 @@ 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,
};
@@ -1209,7 +1213,7 @@ 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,
};
@@ -1227,7 +1231,7 @@ 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,
@@ -1239,7 +1243,7 @@ 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/nfs/nfs4file.c b/fs/nfs/nfs4file.c
index 4288a6ecaf75..ae5780ce41dc 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 int nfs42_remap_file_range(struct file *src_file, loff_t src_off,
+ struct file *dst_file, loff_t dst_off, u64 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) {
@@ -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/ocfs2/file.c b/fs/ocfs2/file.c
index 9fa35cb6f6e0..0b757a24567c 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -2527,24 +2527,18 @@ static loff_t ocfs2_file_llseek(struct file *file, loff_t offset, int whence)
return offset;
}

-static int ocfs2_file_clone_range(struct file *file_in,
+static int ocfs2_remap_file_range(struct file *file_in,
loff_t pos_in,
struct file *file_out,
loff_t pos_out,
- u64 len)
+ u64 len,
+ unsigned int remap_flags)
{
- return ocfs2_reflink_remap_range(file_in, pos_in, file_out, pos_out,
- len, false);
-}
+ if (remap_flags & ~(REMAP_FILE_DEDUP | REMAP_FILE_ADVISORY))
+ return -EINVAL;

-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);
+ len, remap_flags & REMAP_FILE_DEDUP);
}

const struct inode_operations ocfs2_file_iops = {
@@ -2586,8 +2580,7 @@ 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 +2626,7 @@ 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/overlayfs/file.c b/fs/overlayfs/file.c
index 986313da0c88..fffb36fd5920 100644
--- a/fs/overlayfs/file.c
+++ b/fs/overlayfs/file.c
@@ -489,26 +489,31 @@ 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 int ovl_remap_file_range(struct file *file_in, loff_t pos_in,
+ struct file *file_out, loff_t pos_out,
+ u64 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);
+ op);
}

const struct file_operations ovl_file_operations = {
@@ -525,6 +530,5 @@ 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 734c5661fb69..766bdcb381f3 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -1588,9 +1588,9 @@ 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 (file_in->f_op->remap_file_range) {
+ ret = file_in->f_op->remap_file_range(file_in, pos_in,
+ file_out, pos_out, len, 0);
if (ret == 0) {
ret = len;
goto done;
@@ -1849,7 +1849,7 @@ 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 = remap_verify_area(file_in, pos_in, len, false);
@@ -1860,8 +1860,8 @@ int do_clone_file_range(struct file *file_in, loff_t pos_in,
if (ret)
return ret;

- ret = file_in->f_op->clone_file_range(file_in, pos_in,
- file_out, pos_out, len);
+ ret = file_in->f_op->remap_file_range(file_in, pos_in,
+ file_out, pos_out, len, 0);
if (!ret) {
fsnotify_access(file_in);
fsnotify_modify(file_out);
@@ -2006,7 +2006,7 @@ 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;

if (len == 0) {
@@ -2014,8 +2014,8 @@ int vfs_dedupe_file_range_one(struct file *src_file, loff_t src_pos,
goto out_drop_write;
}

- ret = dst_file->f_op->dedupe_file_range(src_file, src_pos,
- dst_file, dst_pos, len);
+ ret = dst_file->f_op->remap_file_range(src_file, src_pos, dst_file,
+ dst_pos, len, REMAP_FILE_DEDUP);
out_drop_write:
mnt_drop_write_file(dst_file);

diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 61a5ad2600e8..2ad94d508f80 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -920,27 +920,19 @@ xfs_file_fallocate(
}

STATIC int
-xfs_file_clone_range(
+xfs_file_remap_range(
struct file *file_in,
loff_t pos_in,
struct file *file_out,
loff_t pos_out,
- u64 len)
+ u64 len,
+ unsigned int remap_flags)
{
- return xfs_reflink_remap_range(file_in, pos_in, file_out, pos_out,
- len, false);
-}
+ if (remap_flags & ~(REMAP_FILE_DEDUP | REMAP_FILE_ADVISORY))
+ return -EINVAL;

-STATIC int
-xfs_file_dedupe_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, true);
+ len, remap_flags & REMAP_FILE_DEDUP);
}

STATIC int
@@ -1175,8 +1167,7 @@ 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/include/linux/fs.h b/include/linux/fs.h
index 55729e1c2e75..888cef35c7d7 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1721,6 +1721,24 @@ 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)
+ */
+#define REMAP_FILE_DEDUP (1 << 0)
+
+/*
+ * 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.
+ * There are no flags yet, but subsequent commits will add some.
+ */
+#define REMAP_FILE_ADVISORY (0)

struct iov_iter;

@@ -1759,10 +1777,9 @@ 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);
+ int (*remap_file_range)(struct file *file_in, loff_t pos_in,
+ struct file *file_out, loff_t pos_out,
+ u64 len, unsigned int remap_flags);
int (*fadvise)(struct file *, loff_t, loff_t, int);
} __randomize_layout;