Message ID | 1389968119-24771-12-git-send-email-kwolf@redhat.com |
---|---|
State | New |
Headers | show |
Le Friday 17 Jan 2014 à 15:15:01 (+0100), Kevin Wolf a écrit : > This separates the part of bdrv_co_do_writev() that needs to happen > before the request is modified to match the backend alignment, and a > part that needs to be executed afterwards and passes the request to the > BlockDriver. > > Signed-off-by: Kevin Wolf <kwolf@redhat.com> > Reviewed-by: Max Reitz <mreitz@redhat.com> > --- > block.c | 62 +++++++++++++++++++++++++++++++++++++++++--------------------- > 1 file changed, 41 insertions(+), 21 deletions(-) > > diff --git a/block.c b/block.c > index f378a10..70b72f0 100644 > --- a/block.c > +++ b/block.c > @@ -2964,34 +2964,20 @@ static int coroutine_fn bdrv_co_do_write_zeroes(BlockDriverState *bs, > } > > /* > - * Handle a write request in coroutine context > + * Forwards an already correctly aligned write request to the BlockDriver. > */ > -static int coroutine_fn bdrv_co_do_writev(BlockDriverState *bs, > - int64_t sector_num, int nb_sectors, QEMUIOVector *qiov, > - BdrvRequestFlags flags) > +static int coroutine_fn bdrv_aligned_pwritev(BlockDriverState *bs, > + int64_t offset, unsigned int bytes, QEMUIOVector *qiov, int flags) > { > BlockDriver *drv = bs->drv; > BdrvTrackedRequest req; > int ret; > > - if (!bs->drv) { > - return -ENOMEDIUM; > - } > - if (bs->read_only) { > - return -EACCES; > - } > - if (bdrv_check_request(bs, sector_num, nb_sectors)) { > - return -EIO; > - } > - > - if (bs->copy_on_read_in_flight) { > - wait_for_overlapping_requests(bs, sector_num, nb_sectors); > - } > + int64_t sector_num = offset >> BDRV_SECTOR_BITS; > + unsigned int nb_sectors = bytes >> BDRV_SECTOR_BITS; > > - /* throttling disk I/O */ > - if (bs->io_limits_enabled) { > - bdrv_io_limits_intercept(bs, nb_sectors, true); > - } > + assert((offset & (BDRV_SECTOR_SIZE - 1)) == 0); > + assert((bytes & (BDRV_SECTOR_SIZE - 1)) == 0); > > tracked_request_begin(&req, bs, sector_num, nb_sectors, true); > > @@ -3023,6 +3009,40 @@ static int coroutine_fn bdrv_co_do_writev(BlockDriverState *bs, > return ret; > } > > +/* > + * Handle a write request in coroutine context > + */ > +static int coroutine_fn bdrv_co_do_writev(BlockDriverState *bs, > + int64_t sector_num, int nb_sectors, QEMUIOVector *qiov, > + BdrvRequestFlags flags) > +{ > + int ret; > + > + if (!bs->drv) { > + return -ENOMEDIUM; > + } > + if (bs->read_only) { > + return -EACCES; > + } > + if (bdrv_check_request(bs, sector_num, nb_sectors)) { > + return -EIO; > + } > + > + if (bs->copy_on_read_in_flight) { > + wait_for_overlapping_requests(bs, sector_num, nb_sectors); > + } > + > + /* throttling disk I/O */ > + if (bs->io_limits_enabled) { > + bdrv_io_limits_intercept(bs, nb_sectors, true); > + } > + > + ret = bdrv_aligned_pwritev(bs, sector_num << BDRV_SECTOR_BITS, > + nb_sectors << BDRV_SECTOR_BITS, qiov, flags); > + > + return ret; > +} > + > int coroutine_fn bdrv_co_writev(BlockDriverState *bs, int64_t sector_num, > int nb_sectors, QEMUIOVector *qiov) > { > -- > 1.8.1.4 > > Reviewed-by: Benoit Canet <benoit@irqsave.net>
diff --git a/block.c b/block.c index f378a10..70b72f0 100644 --- a/block.c +++ b/block.c @@ -2964,34 +2964,20 @@ static int coroutine_fn bdrv_co_do_write_zeroes(BlockDriverState *bs, } /* - * Handle a write request in coroutine context + * Forwards an already correctly aligned write request to the BlockDriver. */ -static int coroutine_fn bdrv_co_do_writev(BlockDriverState *bs, - int64_t sector_num, int nb_sectors, QEMUIOVector *qiov, - BdrvRequestFlags flags) +static int coroutine_fn bdrv_aligned_pwritev(BlockDriverState *bs, + int64_t offset, unsigned int bytes, QEMUIOVector *qiov, int flags) { BlockDriver *drv = bs->drv; BdrvTrackedRequest req; int ret; - if (!bs->drv) { - return -ENOMEDIUM; - } - if (bs->read_only) { - return -EACCES; - } - if (bdrv_check_request(bs, sector_num, nb_sectors)) { - return -EIO; - } - - if (bs->copy_on_read_in_flight) { - wait_for_overlapping_requests(bs, sector_num, nb_sectors); - } + int64_t sector_num = offset >> BDRV_SECTOR_BITS; + unsigned int nb_sectors = bytes >> BDRV_SECTOR_BITS; - /* throttling disk I/O */ - if (bs->io_limits_enabled) { - bdrv_io_limits_intercept(bs, nb_sectors, true); - } + assert((offset & (BDRV_SECTOR_SIZE - 1)) == 0); + assert((bytes & (BDRV_SECTOR_SIZE - 1)) == 0); tracked_request_begin(&req, bs, sector_num, nb_sectors, true); @@ -3023,6 +3009,40 @@ static int coroutine_fn bdrv_co_do_writev(BlockDriverState *bs, return ret; } +/* + * Handle a write request in coroutine context + */ +static int coroutine_fn bdrv_co_do_writev(BlockDriverState *bs, + int64_t sector_num, int nb_sectors, QEMUIOVector *qiov, + BdrvRequestFlags flags) +{ + int ret; + + if (!bs->drv) { + return -ENOMEDIUM; + } + if (bs->read_only) { + return -EACCES; + } + if (bdrv_check_request(bs, sector_num, nb_sectors)) { + return -EIO; + } + + if (bs->copy_on_read_in_flight) { + wait_for_overlapping_requests(bs, sector_num, nb_sectors); + } + + /* throttling disk I/O */ + if (bs->io_limits_enabled) { + bdrv_io_limits_intercept(bs, nb_sectors, true); + } + + ret = bdrv_aligned_pwritev(bs, sector_num << BDRV_SECTOR_BITS, + nb_sectors << BDRV_SECTOR_BITS, qiov, flags); + + return ret; +} + int coroutine_fn bdrv_co_writev(BlockDriverState *bs, int64_t sector_num, int nb_sectors, QEMUIOVector *qiov) {