| Message ID | CA+X5Wn6h8sot6Z7OQVvehD_T4XxHOiss=gT18s_d6EJPZrUhQA@mail.gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Jun 06, 2018 at 02:30:41AM -0400, james harvey wrote: > Prevent unnecessary error from failing fsync(), if opened read only. > > Performed 'grep "writeable = " *.h *.c' to make sure there were no odd > situations where fsync() might still be desired here. They're all straight- > forward. The only situation where writeable will be 0 is if btrfs_open_devices > is given flags without O_RDWR. There is no situation where a writeable volume > temporarily becomes unwriteable, or anything like that. Given that it's being > opened O_RDWR, there's no reason to attempt fsync(). > > utils.c > > int btrfs_add_to_fsid() { > ... > device->writeable = 1; > > volumes.c > > int btrfs_close_devices() { > ... > while (!list_empty(&fs_devices->devices)) { > ... > // just after the fsync() being patched > 267: device->writeable = 0; > ... > int btrfs_open_devices() { > ... > list_for_each_entry(device, &fs_devices->devices, dev_list) { > ... > if (flags & O_RDWR) > 332: device->writeable = 1 > > kernel btrfs_close_devices() does not have a corresponding fsync() that I see. > > Signed-off-by: James Harvey <jamespharvey20@gmail.com> Applied, thanks. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/volumes.c b/volumes.c index c6e34321..36d1bde6 100644 --- a/volumes.c +++ b/volumes.c @@ -254,7 +254,7 @@ again: device = list_entry(fs_devices->devices.next, struct btrfs_device, dev_list); if (device->fd != -1) { - if (fsync(device->fd) == -1) { + if (device->writeable && fsync(device->fd) == -1) { warning("fsync on device %llu failed: %m", device->devid); ret = -errno;
Prevent unnecessary error from failing fsync(), if opened read only. Performed 'grep "writeable = " *.h *.c' to make sure there were no odd situations where fsync() might still be desired here. They're all straight- forward. The only situation where writeable will be 0 is if btrfs_open_devices is given flags without O_RDWR. There is no situation where a writeable volume temporarily becomes unwriteable, or anything like that. Given that it's being opened O_RDWR, there's no reason to attempt fsync(). utils.c int btrfs_add_to_fsid() { ... device->writeable = 1; volumes.c int btrfs_close_devices() { ... while (!list_empty(&fs_devices->devices)) { ... // just after the fsync() being patched 267: device->writeable = 0; ... int btrfs_open_devices() { ... list_for_each_entry(device, &fs_devices->devices, dev_list) { ... if (flags & O_RDWR) 332: device->writeable = 1 kernel btrfs_close_devices() does not have a corresponding fsync() that I see. Signed-off-by: James Harvey <jamespharvey20@gmail.com> --- volumes.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) -- 2.17.0 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html