#include <linux/compat.h>
#include <linux/mount.h>
#include <linux/fs.h>
+#include <linux/dax.h>
+#include <linux/overflow.h>
#include "internal.h"
#include <linux/uaccess.h>
static int remap_verify_area(struct file *file, loff_t pos, loff_t len,
bool write)
{
+ int mask = write ? MAY_WRITE : MAY_READ;
+ loff_t tmp;
+ int ret;
+
if (unlikely(pos < 0 || len < 0))
return -EINVAL;
- if (unlikely((loff_t) (pos + len) < 0))
+ if (unlikely(check_add_overflow(pos, len, &tmp)))
return -EINVAL;
- return security_file_permission(file, write ? MAY_WRITE : MAY_READ);
+ ret = security_file_permission(file, mask);
+ if (ret)
+ return ret;
+
+ return fsnotify_file_area_perm(file, mask, &pos, len);
}
/*
* If there's an error, then the usual negative error code is returned.
* Otherwise returns 0 with *len set to the request length.
*/
-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)
+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,
+ const struct iomap_ops *dax_read_ops)
{
struct inode *inode_in = file_inode(file_in);
struct inode *inode_out = file_inode(file_out);
/* 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)
+ if (ret || *len == 0)
return ret;
/* Wait for the completion of any pending IOs on both files */
if (remap_flags & REMAP_FILE_DEDUP) {
bool is_same = false;
- ret = vfs_dedupe_file_range_compare(file_in, pos_in,
- file_out, pos_out, *len, &is_same);
+ if (!IS_DAX(inode_in))
+ ret = vfs_dedupe_file_range_compare(file_in, pos_in,
+ file_out, pos_out, *len, &is_same);
+ else if (dax_read_ops)
+ ret = dax_dedupe_file_range_compare(inode_in, pos_in,
+ inode_out, pos_out, *len, &is_same,
+ dax_read_ops);
+ else
+ return -EINVAL;
if (ret)
return ret;
if (!is_same)
ret = generic_remap_check_len(inode_in, inode_out, pos_out, len,
remap_flags);
- if (ret)
+ if (ret || *len == 0)
return ret;
/* If can't alter the file contents, we're done. */
return ret;
}
+
+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)
+{
+ return __generic_remap_file_range_prep(file_in, pos_in, file_out,
+ pos_out, len, remap_flags, NULL);
+}
EXPORT_SYMBOL(generic_remap_file_range_prep);
-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)
+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)
{
loff_t ret;
if (ret)
return ret;
+ file_start_write(file_out);
ret = file_in->f_op->remap_file_range(file_in, pos_in,
file_out, pos_out, len, remap_flags);
+ file_end_write(file_out);
if (ret < 0)
return ret;
fsnotify_modify(file_out);
return ret;
}
-EXPORT_SYMBOL(do_clone_file_range);
-
-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)
-{
- loff_t ret;
-
- file_start_write(file_out);
- 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);
/* Check whether we are allowed to dedupe the destination file */
-static bool allow_file_dedupe(struct file *file)
+static bool may_dedupe_file(struct file *file)
{
- struct user_namespace *mnt_userns = file_mnt_user_ns(file);
+ struct mnt_idmap *idmap = file_mnt_idmap(file);
struct inode *inode = file_inode(file);
if (capable(CAP_SYS_ADMIN))
return true;
if (file->f_mode & FMODE_WRITE)
return true;
- if (uid_eq(current_fsuid(), i_uid_into_mnt(mnt_userns, inode)))
+ if (vfsuid_eq_kuid(i_uid_into_vfsuid(idmap, inode), current_fsuid()))
return true;
- if (!inode_permission(mnt_userns, inode, MAY_WRITE))
+ if (!inode_permission(idmap, inode, MAY_WRITE))
return true;
return false;
}
WARN_ON_ONCE(remap_flags & ~(REMAP_FILE_DEDUP |
REMAP_FILE_CAN_SHORTEN));
- ret = mnt_want_write_file(dst_file);
- if (ret)
- return ret;
-
/*
* This is redundant if called from vfs_dedupe_file_range(), but other
* callers need it and it's not performance sesitive...
*/
ret = remap_verify_area(src_file, src_pos, len, false);
if (ret)
- goto out_drop_write;
+ return ret;
ret = remap_verify_area(dst_file, dst_pos, len, true);
if (ret)
- goto out_drop_write;
+ return ret;
+
+ /*
+ * This needs to be called after remap_verify_area() because of
+ * sb_start_write() and before may_dedupe_file() because the mount's
+ * MAY_WRITE need to be checked with mnt_get_write_access_file() held.
+ */
+ ret = mnt_want_write_file(dst_file);
+ if (ret)
+ return ret;
ret = -EPERM;
- if (!allow_file_dedupe(dst_file))
+ if (!may_dedupe_file(dst_file))
goto out_drop_write;
ret = -EXDEV;
projects / linux-2.6-microblaze.git / blobdiff