| Message ID | 20240722040742.11513-14-yaoxt.fnst@fujitsu.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | make range overlap check more readable | expand |
ping. > -----Original Message----- > From: Yao Xingtao <yaoxt.fnst@fujitsu.com> > Sent: Monday, July 22, 2024 12:08 PM > To: qemu-devel@nongnu.org; Kevin Wolf <kwolf@redhat.com>; Hanna Reitz > <hreitz@redhat.com> > Cc: Yao, Xingtao/姚 幸涛 <yaoxt.fnst@fujitsu.com>; qemu-block@nongnu.org > Subject: [PATCH 13/13] block/qcow2-cluster: make range overlap check more > readable > > use range_overlaps_range() instead of open-coding the overlap check to > improve the readability of the code. > > Signed-off-by: Yao Xingtao <yaoxt.fnst@fujitsu.com> > --- > block/qcow2-cluster.c | 23 +++++++++++++---------- > 1 file changed, 13 insertions(+), 10 deletions(-) > > diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c > index ce8c0076b3b5..88d65c4b99e6 100644 > --- a/block/qcow2-cluster.c > +++ b/block/qcow2-cluster.c > @@ -30,6 +30,7 @@ > #include "qcow2.h" > #include "qemu/bswap.h" > #include "qemu/memalign.h" > +#include "qemu/range.h" > #include "trace.h" > > int coroutine_fn qcow2_shrink_l1_table(BlockDriverState *bs, > @@ -1408,23 +1409,25 @@ static int coroutine_fn > handle_dependencies(BlockDriverState *bs, > BDRVQcow2State *s = bs->opaque; > QCowL2Meta *old_alloc; > uint64_t bytes = *cur_bytes; > + Range range1, range2, range3; > > + range_init_nofail(&range1, guest_offset, bytes); > QLIST_FOREACH(old_alloc, &s->cluster_allocs, next_in_flight) { > > - uint64_t start = guest_offset; > - uint64_t end = start + bytes; > - uint64_t old_start = start_of_cluster(s, l2meta_cow_start(old_alloc)); > - uint64_t old_end = ROUND_UP(l2meta_cow_end(old_alloc), > s->cluster_size); > + uint64_t cow_start = l2meta_cow_start(old_alloc); > + uint64_t cow_end = l2meta_cow_end(old_alloc); > + uint64_t start = start_of_cluster(s, cow_start); > + uint64_t end = ROUND_UP(cow_end, s->cluster_size); > > - if (end <= old_start || start >= old_end) { > + range_init_nofail(&range2, start, end - start); > + if (!range_overlaps_range(&range1, &range2)) { > /* No intersection */ > continue; > } > > + range_init_nofail(&range3, cow_start, cow_end - cow_start); > if (old_alloc->keep_old_clusters && > - (end <= l2meta_cow_start(old_alloc) || > - start >= l2meta_cow_end(old_alloc))) > - { > + !range_overlaps_range(&range1, &range3)) { > /* > * Clusters intersect but COW areas don't. And cluster itself is > * already allocated. So, there is no actual conflict. > @@ -1434,9 +1437,9 @@ static int coroutine_fn > handle_dependencies(BlockDriverState *bs, > > /* Conflict */ > > - if (start < old_start) { > + if (guest_offset < start) { > /* Stop at the start of a running allocation */ > - bytes = old_start - start; > + bytes = start - guest_offset; > } else { > bytes = 0; > } > -- > 2.41.0
diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index ce8c0076b3b5..88d65c4b99e6 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -30,6 +30,7 @@ #include "qcow2.h" #include "qemu/bswap.h" #include "qemu/memalign.h" +#include "qemu/range.h" #include "trace.h" int coroutine_fn qcow2_shrink_l1_table(BlockDriverState *bs, @@ -1408,23 +1409,25 @@ static int coroutine_fn handle_dependencies(BlockDriverState *bs, BDRVQcow2State *s = bs->opaque; QCowL2Meta *old_alloc; uint64_t bytes = *cur_bytes; + Range range1, range2, range3; + range_init_nofail(&range1, guest_offset, bytes); QLIST_FOREACH(old_alloc, &s->cluster_allocs, next_in_flight) { - uint64_t start = guest_offset; - uint64_t end = start + bytes; - uint64_t old_start = start_of_cluster(s, l2meta_cow_start(old_alloc)); - uint64_t old_end = ROUND_UP(l2meta_cow_end(old_alloc), s->cluster_size); + uint64_t cow_start = l2meta_cow_start(old_alloc); + uint64_t cow_end = l2meta_cow_end(old_alloc); + uint64_t start = start_of_cluster(s, cow_start); + uint64_t end = ROUND_UP(cow_end, s->cluster_size); - if (end <= old_start || start >= old_end) { + range_init_nofail(&range2, start, end - start); + if (!range_overlaps_range(&range1, &range2)) { /* No intersection */ continue; } + range_init_nofail(&range3, cow_start, cow_end - cow_start); if (old_alloc->keep_old_clusters && - (end <= l2meta_cow_start(old_alloc) || - start >= l2meta_cow_end(old_alloc))) - { + !range_overlaps_range(&range1, &range3)) { /* * Clusters intersect but COW areas don't. And cluster itself is * already allocated. So, there is no actual conflict. @@ -1434,9 +1437,9 @@ static int coroutine_fn handle_dependencies(BlockDriverState *bs, /* Conflict */ - if (start < old_start) { + if (guest_offset < start) { /* Stop at the start of a running allocation */ - bytes = old_start - start; + bytes = start - guest_offset; } else { bytes = 0; }
use range_overlaps_range() instead of open-coding the overlap check to improve the readability of the code. Signed-off-by: Yao Xingtao <yaoxt.fnst@fujitsu.com> --- block/qcow2-cluster.c | 23 +++++++++++++---------- 1 file changed, 13 insertions(+), 10 deletions(-)