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block/io: support int64_t bytes in bdrv_co_p{read,write}v_part()

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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, prepare bdrv_co_preadv_part() and bdrv_co_pwritev_part() and their
remaining dependencies now.

bdrv_pad_request() is updated simultaneously, as pointer to bytes passed
to it both from bdrv_co_pwritev_part() and bdrv_co_preadv_part().

So, all callers of bdrv_pad_request() are updated to pass 64bit bytes.
bdrv_pad_request() is already good for 64bit requests, add
corresponding assertion.

Look at bdrv_co_preadv_part() and bdrv_co_pwritev_part().
Type is widening, so callers are safe. Let's look inside the functions.

In bdrv_co_preadv_part() and bdrv_aligned_pwritev() we only pass bytes
to other already int64_t interfaces (and some obviously safe
calculations), it's OK.

In bdrv_co_do_zero_pwritev() aligned_bytes may become large now, still
it's passed to bdrv_aligned_pwritev which supports int64_t bytes.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20201211183934.169161-15-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
This commit is contained in:
Vladimir Sementsov-Ogievskiy 2020-12-11 21:39:32 +03:00 • committed by Eric Blake
parent 8b0c5d7659
commit 37e9403ea8
3 changed files with 12 additions and 10 deletions
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4
block/trace-events
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@ -11,8 +11,8 @@ blk_root_attach(void *child, void *blk, void *bs) "child %p blk %p bs %p"
blk_root_detach(void *child, void *blk, void *bs) "child %p blk %p bs %p"
# io.c
bdrv_co_preadv(void *bs, int64_t offset, int64_t nbytes, unsigned int flags) "bs %p offset %"PRId64" nbytes %"PRId64" flags 0x%x"
bdrv_co_pwritev(void *bs, int64_t offset, int64_t nbytes, unsigned int flags) "bs %p offset %"PRId64" nbytes %"PRId64" flags 0x%x"
bdrv_co_preadv_part(void *bs, int64_t offset, int64_t bytes, unsigned int flags) "bs %p offset %" PRId64 " bytes %" PRId64 " flags 0x%x"
bdrv_co_pwritev_part(void *bs, int64_t offset, int64_t bytes, unsigned int flags) "bs %p offset %" PRId64 " bytes %" PRId64 " flags 0x%x"
bdrv_co_pwrite_zeroes(void *bs, int64_t offset, int count, int flags) "bs %p offset %"PRId64" count %d flags 0x%x"
bdrv_co_do_copy_on_readv(void *bs, int64_t offset, int64_t bytes, int64_t cluster_offset, int64_t cluster_bytes) "bs %p offset %" PRId64 " bytes %" PRId64 " cluster_offset %" PRId64 " cluster_bytes %" PRId64
bdrv_co_copy_range_from(void *src, uint64_t src_offset, void *dst, uint64_t dst_offset, uint64_t bytes, int read_flags, int write_flags) "src %p offset %"PRIu64" dst %p offset %"PRIu64" bytes %"PRIu64" rw flags 0x%x 0x%x"