From: Ross Zwisler <zwisler@xxxxxxxxxxxx> commit aa0bfcd939c30617385ffa28682c062d78050eba upstream. In the spirit of filemap_fdatawait_range() and filemap_fdatawait_keep_errors(), introduce filemap_fdatawait_range_keep_errors() which both takes a range upon which to wait and does not clear errors from the address space. Signed-off-by: Ross Zwisler <zwisler@xxxxxxxxxx> Signed-off-by: Theodore Ts'o <tytso@xxxxxxx> Reviewed-by: Jan Kara <jack@xxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- include/linux/fs.h | 2 ++ mm/filemap.c | 22 ++++++++++++++++++++++ 2 files changed, 24 insertions(+) --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2651,6 +2651,8 @@ extern int filemap_flush(struct address_ extern int filemap_fdatawait_keep_errors(struct address_space *mapping); extern int filemap_fdatawait_range(struct address_space *, loff_t lstart, loff_t lend); +extern int filemap_fdatawait_range_keep_errors(struct address_space *mapping, + loff_t start_byte, loff_t end_byte); static inline int filemap_fdatawait(struct address_space *mapping) { --- a/mm/filemap.c +++ b/mm/filemap.c @@ -562,6 +562,28 @@ int filemap_fdatawait_range(struct addre EXPORT_SYMBOL(filemap_fdatawait_range); /** + * filemap_fdatawait_range_keep_errors - wait for writeback to complete + * @mapping: address space structure to wait for + * @start_byte: offset in bytes where the range starts + * @end_byte: offset in bytes where the range ends (inclusive) + * + * Walk the list of under-writeback pages of the given address space in the + * given range and wait for all of them. Unlike filemap_fdatawait_range(), + * this function does not clear error status of the address space. + * + * Use this function if callers don't handle errors themselves. Expected + * call sites are system-wide / filesystem-wide data flushers: e.g. sync(2), + * fsfreeze(8) + */ +int filemap_fdatawait_range_keep_errors(struct address_space *mapping, + loff_t start_byte, loff_t end_byte) +{ + __filemap_fdatawait_range(mapping, start_byte, end_byte); + return filemap_check_and_keep_errors(mapping); +} +EXPORT_SYMBOL(filemap_fdatawait_range_keep_errors); + +/** * file_fdatawait_range - wait for writeback to complete * @file: file pointing to address space structure to wait for * @start_byte: offset in bytes where the range starts