| Message ID | 1554120365-39119-2-git-send-email-andrey.shinkevich@virtuozzo.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | block/stream: get rid of the base | expand |
01.04.2019 15:06, Andrey Shinkevich wrote: > This patch is used in the 'block/stream: introduce a bottom node' > that is following. Instead of the base node, the caller may pass > the node that has the base as its backing image to the new function > bdrv_is_allocated_above_inclusive() and get rid of the dependency > on the base that may change during commit/stream parallel jobs. > If the specified base is not found in the backing image chain, the > function fails. More honest: s/fail/now crashes/ And I think it's correct. But it would be good to check all callers.. Do we freeze backing chain in all cases before calling this function? > > Suggested-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> > Signed-off-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com> > --- > block/io.c | 32 +++++++++++++++++++++++++++----- > include/block/block.h | 5 ++++- > 2 files changed, 31 insertions(+), 6 deletions(-) > > diff --git a/block/io.c b/block/io.c > index dfc153b..7edeeb2 100644 > --- a/block/io.c > +++ b/block/io.c > @@ -2317,7 +2317,8 @@ int coroutine_fn bdrv_is_allocated(BlockDriverState *bs, int64_t offset, > * Given an image chain: ... -> [BASE] -> [INTER1] -> [INTER2] -> [TOP] > * > * Return true if (a prefix of) the given range is allocated in any image > - * between BASE and TOP (inclusive). BASE can be NULL to check if the given > + * between BASE and TOP (TOP included). To check the BASE image, set the > + * 'base_included' to 'true'. The BASE can be NULL to check if the given > * offset is allocated in any image of the chain. Return false otherwise, > * or negative errno on failure. > * > @@ -2329,16 +2330,18 @@ int coroutine_fn bdrv_is_allocated(BlockDriverState *bs, int64_t offset, > * but 'pnum' will only be 0 when end of file is reached. > * > */ > -int bdrv_is_allocated_above(BlockDriverState *top, > - BlockDriverState *base, > - int64_t offset, int64_t bytes, int64_t *pnum) > +static int bdrv_do_is_allocated_above(BlockDriverState *top, > + BlockDriverState *base, > + bool base_included, int64_t offset, > + int64_t bytes, int64_t *pnum) > { > BlockDriverState *intermediate; > int ret; > int64_t n = bytes; empty line after variable definitions > + assert(base || !base_included); > > intermediate = top; > - while (intermediate && intermediate != base) { > + while (base_included || intermediate != base) { > int64_t pnum_inter; > int64_t size_inter; > > @@ -2360,6 +2363,10 @@ int bdrv_is_allocated_above(BlockDriverState *top, > n = pnum_inter; > } > > + if (intermediate == base) { > + break; > + } > + > intermediate = backing_bs(intermediate); > } > > @@ -2367,6 +2374,21 @@ int bdrv_is_allocated_above(BlockDriverState *top, > return 0; > } > > +int bdrv_is_allocated_above(BlockDriverState *top, > + BlockDriverState *base, > + int64_t offset, int64_t bytes, int64_t *pnum) > +{ > + return bdrv_do_is_allocated_above(top, base, false, offset, bytes, pnum); > +} > + > +int bdrv_is_allocated_above_inclusive(BlockDriverState *top, > + BlockDriverState *base, > + int64_t offset, int64_t bytes, > + int64_t *pnum) > +{ > + return bdrv_do_is_allocated_above(top, base, true, offset, bytes, pnum); > +} > + > typedef struct BdrvVmstateCo { > BlockDriverState *bs; > QEMUIOVector *qiov; > diff --git a/include/block/block.h b/include/block/block.h > index c7a2619..a7846d9 100644 > --- a/include/block/block.h > +++ b/include/block/block.h > @@ -448,7 +448,10 @@ int bdrv_is_allocated(BlockDriverState *bs, int64_t offset, int64_t bytes, > int64_t *pnum); > int bdrv_is_allocated_above(BlockDriverState *top, BlockDriverState *base, > int64_t offset, int64_t bytes, int64_t *pnum); > - > +int bdrv_is_allocated_above_inclusive(BlockDriverState *top, > + BlockDriverState *base, > + int64_t offset, int64_t bytes, > + int64_t *pnum); dropped empty line better stay here. > bool bdrv_is_read_only(BlockDriverState *bs); > int bdrv_can_set_read_only(BlockDriverState *bs, bool read_only, > bool ignore_allow_rdw, Error **errp); > Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
diff --git a/block/io.c b/block/io.c index dfc153b..7edeeb2 100644 --- a/block/io.c +++ b/block/io.c @@ -2317,7 +2317,8 @@ int coroutine_fn bdrv_is_allocated(BlockDriverState *bs, int64_t offset, * Given an image chain: ... -> [BASE] -> [INTER1] -> [INTER2] -> [TOP] * * Return true if (a prefix of) the given range is allocated in any image - * between BASE and TOP (inclusive). BASE can be NULL to check if the given + * between BASE and TOP (TOP included). To check the BASE image, set the + * 'base_included' to 'true'. The BASE can be NULL to check if the given * offset is allocated in any image of the chain. Return false otherwise, * or negative errno on failure. * @@ -2329,16 +2330,18 @@ int coroutine_fn bdrv_is_allocated(BlockDriverState *bs, int64_t offset, * but 'pnum' will only be 0 when end of file is reached. * */ -int bdrv_is_allocated_above(BlockDriverState *top, - BlockDriverState *base, - int64_t offset, int64_t bytes, int64_t *pnum) +static int bdrv_do_is_allocated_above(BlockDriverState *top, + BlockDriverState *base, + bool base_included, int64_t offset, + int64_t bytes, int64_t *pnum) { BlockDriverState *intermediate; int ret; int64_t n = bytes; + assert(base || !base_included); intermediate = top; - while (intermediate && intermediate != base) { + while (base_included || intermediate != base) { int64_t pnum_inter; int64_t size_inter; @@ -2360,6 +2363,10 @@ int bdrv_is_allocated_above(BlockDriverState *top, n = pnum_inter; } + if (intermediate == base) { + break; + } + intermediate = backing_bs(intermediate); } @@ -2367,6 +2374,21 @@ int bdrv_is_allocated_above(BlockDriverState *top, return 0; } +int bdrv_is_allocated_above(BlockDriverState *top, + BlockDriverState *base, + int64_t offset, int64_t bytes, int64_t *pnum) +{ + return bdrv_do_is_allocated_above(top, base, false, offset, bytes, pnum); +} + +int bdrv_is_allocated_above_inclusive(BlockDriverState *top, + BlockDriverState *base, + int64_t offset, int64_t bytes, + int64_t *pnum) +{ + return bdrv_do_is_allocated_above(top, base, true, offset, bytes, pnum); +} + typedef struct BdrvVmstateCo { BlockDriverState *bs; QEMUIOVector *qiov; diff --git a/include/block/block.h b/include/block/block.h index c7a2619..a7846d9 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -448,7 +448,10 @@ int bdrv_is_allocated(BlockDriverState *bs, int64_t offset, int64_t bytes, int64_t *pnum); int bdrv_is_allocated_above(BlockDriverState *top, BlockDriverState *base, int64_t offset, int64_t bytes, int64_t *pnum); - +int bdrv_is_allocated_above_inclusive(BlockDriverState *top, + BlockDriverState *base, + int64_t offset, int64_t bytes, + int64_t *pnum); bool bdrv_is_read_only(BlockDriverState *bs); int bdrv_can_set_read_only(BlockDriverState *bs, bool read_only, bool ignore_allow_rdw, Error **errp);
This patch is used in the 'block/stream: introduce a bottom node' that is following. Instead of the base node, the caller may pass the node that has the base as its backing image to the new function bdrv_is_allocated_above_inclusive() and get rid of the dependency on the base that may change during commit/stream parallel jobs. If the specified base is not found in the backing image chain, the function fails. Suggested-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com> --- block/io.c | 32 +++++++++++++++++++++++++++----- include/block/block.h | 5 ++++- 2 files changed, 31 insertions(+), 6 deletions(-)