[PATCH 01/15] vfs: export remap and write check helpers

["Darrick J. Wong" <djwong@kernel.org>]

From: Darrick J. Wong <djwong@kernel.org>

Export these functions so that the next patch can use them to check the
file ranges being passed to the XFS_IOC_EXCHANGE_RANGE operation.

Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
 fs/read_write.c    |    1 +
 fs/remap_range.c   |    4 ++--
 include/linux/fs.h |    1 +
 3 files changed, 4 insertions(+), 2 deletions(-)


diff --git a/fs/read_write.c b/fs/read_write.c
index d4c036e82b6c..85c096f2c0d0 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -1667,6 +1667,7 @@ int generic_write_check_limits(struct file *file, loff_t pos, loff_t *count)
 
 	return 0;
 }
+EXPORT_SYMBOL_GPL(generic_write_check_limits);
 
 /* Like generic_write_checks(), but takes size of write instead of iter. */
 int generic_write_checks_count(struct kiocb *iocb, loff_t *count)
diff --git a/fs/remap_range.c b/fs/remap_range.c
index de07f978ce3e..28246dfc8485 100644
--- a/fs/remap_range.c
+++ b/fs/remap_range.c
@@ -99,8 +99,7 @@ static int generic_remap_checks(struct file *file_in, loff_t pos_in,
 	return 0;
 }
 
-static int remap_verify_area(struct file *file, loff_t pos, loff_t len,
-			     bool write)
+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;
@@ -118,6 +117,7 @@ static int remap_verify_area(struct file *file, loff_t pos, loff_t len,
 
 	return fsnotify_file_area_perm(file, mask, &pos, len);
 }
+EXPORT_SYMBOL_GPL(remap_verify_area);
 
 /*
  * Ensure that we don't remap a partial EOF block in the middle of something
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 8dfd53b52744..0835faeebe7b 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2119,6 +2119,7 @@ extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *);
 extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *);
 extern ssize_t vfs_copy_file_range(struct file *, loff_t , struct file *,
 				   loff_t, size_t, unsigned int);
+int remap_verify_area(struct file *file, loff_t pos, loff_t len, bool write);
 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,