generic_writepages — walk the list of dirty pages of the given
int generic_writepages ( | struct address_space * | mapping, |
struct writeback_control * | wbc) ; |
mapping
address space structure to write
wbc
subtract the number of written pages from *wbc
->nr_to_write
This is a library function, which implements the writepages
address_space_operation.
If a page is already under I/O, generic_writepages
skips it, even
if it's dirty. This is desirable behaviour for memory-cleaning writeback,
but it is INCORRECT for data-integrity system calls such as fsync
. fsync
and msync
need to guarantee that all the data which was dirty at the time
the call was made get new I/O started against them. If wbc->sync_mode is
WB_SYNC_ALL then we were called for data integrity and we must wait for
existing IO to complete.
Derived from mpage_writepages
- if you fix this you should check that
also!
This is a library function, which implements the writepages
address_space_operation.
If a page is already under I/O, generic_writepages
skips it, even
if it's dirty. This is desirable behaviour for memory-cleaning writeback,
but it is INCORRECT for data-integrity system calls such as fsync
. fsync
and msync
need to guarantee that all the data which was dirty at the time
the call was made get new I/O started against them. If wbc->sync_mode is
WB_SYNC_ALL then we were called for data integrity and we must wait for
existing IO to complete.
Derived from mpage_writepages
- if you fix this you should check that
also!