This just pulls out the ksys_sync_file_range() code to work on a struct
file instead of an fd, so we can use it elsewhere.
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
---
fs/sync.c | 135 ++++++++++++++++++++++++---------------------
include/linux/fs.h | 3 +
2 files changed, 74 insertions(+), 64 deletions(-)
diff --git a/fs/sync.c b/fs/sync.c
index b54e0541ad89..01e82170545a 100644
--- a/fs/sync.c
+++ b/fs/sync.c
@@ -234,58 +234,10 @@ SYSCALL_DEFINE1(fdatasync, unsigned int, fd)
return do_fsync(fd, 1);
}
-/*
- * sys_sync_file_range() permits finely controlled syncing over a segment of
- * a file in the range offset .. (offset+nbytes-1) inclusive. If nbytes is
- * zero then sys_sync_file_range() will operate from offset out to EOF.
- *
- * The flag bits are:
- *
- * SYNC_FILE_RANGE_WAIT_BEFORE: wait upon writeout of all pages in the range
- * before performing the write.
- *
- * SYNC_FILE_RANGE_WRITE: initiate writeout of all those dirty pages in the
- * range which are not presently under writeback. Note that this may block for
- * significant periods due to exhaustion of disk request structures.
- *
- * SYNC_FILE_RANGE_WAIT_AFTER: wait upon writeout of all pages in the range
- * after performing the write.
- *
- * Useful combinations of the flag bits are:
- *
- * SYNC_FILE_RANGE_WAIT_BEFORE|SYNC_FILE_RANGE_WRITE: ensures that all pages
- * in the range which were dirty on entry to sys_sync_file_range() are placed
- * under writeout. This is a start-write-for-data-integrity operation.
- *
- * SYNC_FILE_RANGE_WRITE: start writeout of all dirty pages in the range which
- * are not presently under writeout. This is an asynchronous flush-to-disk
- * operation. Not suitable for data integrity operations.
- *
- * SYNC_FILE_RANGE_WAIT_BEFORE (or SYNC_FILE_RANGE_WAIT_AFTER): wait for
- * completion of writeout of all pages in the range. This will be used after an
- * earlier SYNC_FILE_RANGE_WAIT_BEFORE|SYNC_FILE_RANGE_WRITE operation to wait
- * for that operation to complete and to return the result.
- *
- * SYNC_FILE_RANGE_WAIT_BEFORE|SYNC_FILE_RANGE_WRITE|SYNC_FILE_RANGE_WAIT_AFTER:
- * a traditional sync() operation. This is a write-for-data-integrity operation
- * which will ensure that all pages in the range which were dirty on entry to
- * sys_sync_file_range() are committed to disk.
- *
- *
- * SYNC_FILE_RANGE_WAIT_BEFORE and SYNC_FILE_RANGE_WAIT_AFTER will detect any
- * I/O errors or ENOSPC conditions and will return those to the caller, after
- * clearing the EIO and ENOSPC flags in the address_space.
- *
- * It should be noted that none of these operations write out the file's
- * metadata. So unless the application is strictly performing overwrites of
- * already-instantiated disk blocks, there are no guarantees here that the data
- * will be available after a crash.
- */
-int ksys_sync_file_range(int fd, loff_t offset, loff_t nbytes,
- unsigned int flags)
+int sync_file_range(struct file *file, loff_t offset, loff_t nbytes,
+ unsigned int flags)
{
int ret;
- struct fd f;
struct address_space *mapping;
loff_t endbyte; /* inclusive */
umode_t i_mode;
@@ -325,41 +277,96 @@ int ksys_sync_file_range(int fd, loff_t offset, loff_t nbytes,
else
endbyte--; /* inclusive */
- ret = -EBADF;
- f = fdget(fd);
- if (!f.file)
- goto out;
-
- i_mode = file_inode(f.file)->i_mode;
+ i_mode = file_inode(file)->i_mode;
ret = -ESPIPE;
if (!S_ISREG(i_mode) && !S_ISBLK(i_mode) && !S_ISDIR(i_mode) &&
!S_ISLNK(i_mode))
- goto out_put;
+ goto out;
- mapping = f.file->f_mapping;
+ mapping = file->f_mapping;
ret = 0;
if (flags & SYNC_FILE_RANGE_WAIT_BEFORE) {
- ret = file_fdatawait_range(f.file, offset, endbyte);
+ ret = file_fdatawait_range(file, offset, endbyte);
if (ret < 0)
- goto out_put;
+ goto out;
}
if (flags & SYNC_FILE_RANGE_WRITE) {
ret = __filemap_fdatawrite_range(mapping, offset, endbyte,
WB_SYNC_NONE);
if (ret < 0)
- goto out_put;
+ goto out;
}
if (flags & SYNC_FILE_RANGE_WAIT_AFTER)
- ret = file_fdatawait_range(f.file, offset, endbyte);
+ ret = file_fdatawait_range(file, offset, endbyte);
-out_put:
- fdput(f);
out:
return ret;
}
+/*
+ * sys_sync_file_range() permits finely controlled syncing over a segment of
+ * a file in the range offset .. (offset+nbytes-1) inclusive. If nbytes is
+ * zero then sys_sync_file_range() will operate from offset out to EOF.
+ *
+ * The flag bits are:
+ *
+ * SYNC_FILE_RANGE_WAIT_BEFORE: wait upon writeout of all pages in the range
+ * before performing the write.
+ *
+ * SYNC_FILE_RANGE_WRITE: initiate writeout of all those dirty pages in the
+ * range which are not presently under writeback. Note that this may block for
+ * significant periods due to exhaustion of disk request structures.
+ *
+ * SYNC_FILE_RANGE_WAIT_AFTER: wait upon writeout of all pages in the range
+ * after performing the write.
+ *
+ * Useful combinations of the flag bits are:
+ *
+ * SYNC_FILE_RANGE_WAIT_BEFORE|SYNC_FILE_RANGE_WRITE: ensures that all pages
+ * in the range which were dirty on entry to sys_sync_file_range() are placed
+ * under writeout. This is a start-write-for-data-integrity operation.
+ *
+ * SYNC_FILE_RANGE_WRITE: start writeout of all dirty pages in the range which
+ * are not presently under writeout. This is an asynchronous flush-to-disk
+ * operation. Not suitable for data integrity operations.
+ *
+ * SYNC_FILE_RANGE_WAIT_BEFORE (or SYNC_FILE_RANGE_WAIT_AFTER): wait for
+ * completion of writeout of all pages in the range. This will be used after an
+ * earlier SYNC_FILE_RANGE_WAIT_BEFORE|SYNC_FILE_RANGE_WRITE operation to wait
+ * for that operation to complete and to return the result.
+ *
+ * SYNC_FILE_RANGE_WAIT_BEFORE|SYNC_FILE_RANGE_WRITE|SYNC_FILE_RANGE_WAIT_AFTER:
+ * a traditional sync() operation. This is a write-for-data-integrity operation
+ * which will ensure that all pages in the range which were dirty on entry to
+ * sys_sync_file_range() are committed to disk.
+ *
+ *
+ * SYNC_FILE_RANGE_WAIT_BEFORE and SYNC_FILE_RANGE_WAIT_AFTER will detect any
+ * I/O errors or ENOSPC conditions and will return those to the caller, after
+ * clearing the EIO and ENOSPC flags in the address_space.
+ *
+ * It should be noted that none of these operations write out the file's
+ * metadata. So unless the application is strictly performing overwrites of
+ * already-instantiated disk blocks, there are no guarantees here that the data
+ * will be available after a crash.
+ */
+int ksys_sync_file_range(int fd, loff_t offset, loff_t nbytes,
+ unsigned int flags)
+{
+ int ret;
+ struct fd f;
+
+ ret = -EBADF;
+ f = fdget(fd);
+ if (f.file)
+ ret = sync_file_range(f.file, offset, nbytes, flags);
+
+ fdput(f);
+ return ret;
+}
+
SYSCALL_DEFINE4(sync_file_range, int, fd, loff_t, offset, loff_t, nbytes,
unsigned int, flags)
{
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 8b42df09b04c..84e2c45ff989 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2782,6 +2782,9 @@ extern int vfs_fsync_range(struct file *file, loff_t start, loff_t end,
int datasync);
extern int vfs_fsync(struct file *file, int datasync);
+extern int sync_file_range(struct file *file, loff_t offset, loff_t nbytes,
+ unsigned int flags);
+
/*
* Sync the bytes written if this was a synchronous write. Expect ki_pos
* to already be updated for the write, and will return either the amount
--
2.17.1
