On Wed, May 05, 2021 at 10:50:00AM +0300, Vladimir Sementsov-Ogievskiy wrote: > We are generally moving to int64_t for both offset and bytes parameters > on all io paths. > > Main motivation is realization of 64-bit write_zeroes operation for > fast zeroing large disk chunks, up to the whole disk. > > We chose signed type, to be consistent with off_t (which is signed) and > with possibility for signed return type (where negative value means > error). > > So, convert driver discard handlers bytes parameter to int64_t. > > The only caller of all updated function is bdrv_co_pdiscard in > block/io.c. It is already prepared to work with 64bit requests, but > pass at most max(bs->bl.max_pdiscard, INT_MAX) to the driver. > > Let's look at all updated functions: > > backup-top: pass to bdrv_co_pdiscard which is 64bit
and to backup_top_cbw, but that is also 64-bit > > blkdebug: all calculations are still OK, thanks to > bdrv_check_qiov_request(). > both rule_check and bdrv_co_pdiscard are 64bit > > blklogwrites: pass to blk_loc_writes_co_log which is 64bit > > blkreply, copy-on-read, filter-compress: pass to bdrv_co_pdiscard, OK blkreplay > > file-posix: one handler calls raw_account_discard() is 64bit and both > handlers calls raw_do_pdiscard(). Update raw_do_pdiscard, which pass > to RawPosixAIOData::aio_nbytes, which is 64bit (and calls > raw_account_discard()) > > gluster: somehow, third argument of glfs_discard_async is size_t. > Let's set max_pdiscard accordingly. > > iscsi: iscsi_allocmap_set_invalid is 64bit, > !is_byte_request_lun_aligned is 64bit. > list.num is uint32_t. Let's clarify max_pdiscard and > pdiscard_alignment. The patch tweaks max_pdiscard, but doesn't change pdiscard_alignment. > > mirror_top, preallocate: pass to bdrv_mirror_top_do_write() which is > 64bit file is mirror.c, not mirror-top.c. But it matches the BlockDriver bdrv_mirror_top name. preallocate does not call bdrv_mirror_top_do_write, so it's probably worth separating that line out. > > nbd: protocol limitation. max_pdiscard is alredy set strict enough, > keep it as is for now. > > nvmd: buf.nlb is uint32_t and we do shift. So, add corresponding limits > to nvme_refresh_limits(). nvme > > qcow2: calculations are still OK, thanks to bdrv_check_qiov_request(), > qcow2_cluster_discard() is 64bit. > > raw-format: raw_adjust_offset() is 64bit, bdrv_co_pdiscard too. > > sheepdog: the format is deprecated. Don't care and just make old > INT_MAX limit to be explicit > > throttle: pass to bdrv_co_pdiscard() which is 64bit and to > throttle_group_co_io_limits_intercept() which is 64bit as well. > > test-block-iothread: bytes argument is unused > > Great! Now all drivers are prepared to 64bit discard requests or has > explicit max_pdiscard limit. are prepared to handle 64-bit discard requests, or else have explicit max_pdiscard limits. > > Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com> > --- > include/block/block_int.h | 2 +- > block/backup-top.c | 2 +- > block/blkdebug.c | 2 +- > block/blklogwrites.c | 4 ++-- > block/blkreplay.c | 2 +- > block/copy-on-read.c | 2 +- > block/file-posix.c | 7 ++++--- > block/filter-compress.c | 2 +- > block/gluster.c | 7 +++++-- > block/iscsi.c | 10 +++++----- > block/mirror.c | 2 +- > block/nbd.c | 6 ++++-- > block/nvme.c | 14 +++++++++++++- > block/preallocate.c | 2 +- > block/qcow2.c | 2 +- > block/raw-format.c | 2 +- > block/sheepdog.c | 15 ++++++++++++++- > block/throttle.c | 2 +- > tests/unit/test-block-iothread.c | 2 +- > block/trace-events | 4 ++-- > 20 files changed, 61 insertions(+), 30 deletions(-) > > +++ b/block/gluster.c > @@ -891,6 +891,7 @@ out: > static void qemu_gluster_refresh_limits(BlockDriverState *bs, Error **errp) > { > bs->bl.max_transfer = GLUSTER_MAX_TRANSFER; > + bs->bl.max_pdiscard = SIZE_MAX; We probably want this to be MIN(GLUSTER_MAX_TRANSFER, SIZE_MAX). Also, do we want to round it down to alignment boundaries? > +++ b/block/iscsi.c > @@ -1141,7 +1141,8 @@ iscsi_getlength(BlockDriverState *bs) > } > > static int > -coroutine_fn iscsi_co_pdiscard(BlockDriverState *bs, int64_t offset, int > bytes) > +coroutine_fn iscsi_co_pdiscard(BlockDriverState *bs, int64_t offset, > + int64_t bytes) > { > IscsiLun *iscsilun = bs->opaque; > struct IscsiTask iTask; Did you want to add some sort of assert(bytes / iscsilun->block_size <= UINT32_MAX), or a comment that we are relying on bl.max_pdiscard? > +++ b/block/sheepdog.c > +static void sd_refresh_limits(BlockDriverState *bs, Error **errp) > +{ > + bs->bl.max_pdiscard = INT_MAX; Do we want to round this down to alignment? Looks close! -- Eric Blake, Principal Software Engineer Red Hat, Inc. +1-919-301-3266 Virtualization: qemu.org | libvirt.org