| Message ID | 1381125551-24354-1-git-send-email-pl@kamp.de |
|---|---|
| State | New |
| Headers | show |
Il 07/10/2013 07:59, Peter Lieven ha scritto: > if a raw device like an iscsi target or host device is used > the current implementation makes a second call out to get > the block status of bs->file. > > Signed-off-by: Peter Lieven <pl@kamp.de> > --- > v5: add a generic get_lba_status function in the raw driver which > adds the BDRV_BLOCK_RAW flag. bdrv_co_get_block_status will > handle the callout to bs->file then. > > v4: use a flag to detect the raw driver instead of the strncmp > hack > > block.c | 4 ++++ > block/raw_bsd.c | 3 ++- > include/block/block.h | 4 ++++ > 3 files changed, 10 insertions(+), 1 deletion(-) > > diff --git a/block.c b/block.c > index 93e113a..38a589e 100644 > --- a/block.c > +++ b/block.c > @@ -3147,6 +3147,10 @@ static int64_t coroutine_fn bdrv_co_get_block_status(BlockDriverState *bs, > return ret; > } > > + if (ret & BDRV_BLOCK_RAW) { > + return bdrv_get_block_status(bs->file, sector_num, nb_sectors, pnum); Strictly speaking, this should probably do something like this: assert(ret & BDRV_BLOCK_OFFSET_VALID); return bdrv_get_block_status(bs->file, ret >> BDRV_SECTOR_BITS, nb_sectors, pnum); Or alternatively the raw driver should return just "BDRV_BLOCK_RAW". As a third option, the raw driver could also return not just BDRV_BLOCK_RAW and BDRV_BLOCK_OFFSET_VALID, but also BDRV_BLOCK_DATA (so that the answer makes some sense even without going down to bs->file). But I'll let the block maintainers decide what to do. Paolo > + } > + > if (!(ret & BDRV_BLOCK_DATA)) { > if (bdrv_has_zero_init(bs)) { > ret |= BDRV_BLOCK_ZERO; > diff --git a/block/raw_bsd.c b/block/raw_bsd.c > index d4ace60..308d605 100644 > --- a/block/raw_bsd.c > +++ b/block/raw_bsd.c > @@ -62,7 +62,8 @@ static int64_t coroutine_fn raw_co_get_block_status(BlockDriverState *bs, > int64_t sector_num, > int nb_sectors, int *pnum) > { > - return bdrv_get_block_status(bs->file, sector_num, nb_sectors, pnum); > + return BDRV_BLOCK_RAW | BDRV_BLOCK_OFFSET_VALID | > + (sector_num << BDRV_SECTOR_BITS); > } > > static int coroutine_fn raw_co_write_zeroes(BlockDriverState *bs, > diff --git a/include/block/block.h b/include/block/block.h > index f808550..003699e 100644 > --- a/include/block/block.h > +++ b/include/block/block.h > @@ -84,6 +84,9 @@ typedef struct BlockDevOps { > /* BDRV_BLOCK_DATA: data is read from bs->file or another file > * BDRV_BLOCK_ZERO: sectors read as zero > * BDRV_BLOCK_OFFSET_VALID: sector stored in bs->file as raw data > + * BDRV_BLOCK_RAW: used internally to indicate that the request > + * was answered by the raw driver and that one > + * should look in bs->file directly. > * > * If BDRV_BLOCK_OFFSET_VALID is set, bits 9-62 represent the offset in > * bs->file where sector data can be read from as raw data. > @@ -105,6 +108,7 @@ typedef struct BlockDevOps { > #define BDRV_BLOCK_DATA 1 > #define BDRV_BLOCK_ZERO 2 > #define BDRV_BLOCK_OFFSET_VALID 4 > +#define BDRV_BLOCK_RAW 8 > #define BDRV_BLOCK_OFFSET_MASK BDRV_SECTOR_MASK > > typedef enum { >
On 07.10.2013 10:25, Paolo Bonzini wrote: > Il 07/10/2013 07:59, Peter Lieven ha scritto: >> if a raw device like an iscsi target or host device is used >> the current implementation makes a second call out to get >> the block status of bs->file. >> >> Signed-off-by: Peter Lieven <pl@kamp.de> >> --- >> v5: add a generic get_lba_status function in the raw driver which >> adds the BDRV_BLOCK_RAW flag. bdrv_co_get_block_status will >> handle the callout to bs->file then. >> >> v4: use a flag to detect the raw driver instead of the strncmp >> hack >> >> block.c | 4 ++++ >> block/raw_bsd.c | 3 ++- >> include/block/block.h | 4 ++++ >> 3 files changed, 10 insertions(+), 1 deletion(-) >> >> diff --git a/block.c b/block.c >> index 93e113a..38a589e 100644 >> --- a/block.c >> +++ b/block.c >> @@ -3147,6 +3147,10 @@ static int64_t coroutine_fn bdrv_co_get_block_status(BlockDriverState *bs, >> return ret; >> } >> >> + if (ret & BDRV_BLOCK_RAW) { >> + return bdrv_get_block_status(bs->file, sector_num, nb_sectors, pnum); > Strictly speaking, this should probably do something like this: > > assert(ret & BDRV_BLOCK_OFFSET_VALID); > return bdrv_get_block_status(bs->file, ret >> BDRV_SECTOR_BITS, > nb_sectors, pnum); > > Or alternatively the raw driver should return just "BDRV_BLOCK_RAW". > > As a third option, the raw driver could also return not just > BDRV_BLOCK_RAW and BDRV_BLOCK_OFFSET_VALID, but also BDRV_BLOCK_DATA (so > that the answer makes some sense even without going down to bs->file). > > But I'll let the block maintainers decide what to do. Okay, I will wait for their feedback. Peter
On Mon, Oct 7, 2013 at 10:25 AM, Paolo Bonzini <pbonzini@redhat.com> wrote: > Il 07/10/2013 07:59, Peter Lieven ha scritto: >> if a raw device like an iscsi target or host device is used >> the current implementation makes a second call out to get >> the block status of bs->file. >> >> Signed-off-by: Peter Lieven <pl@kamp.de> >> --- >> v5: add a generic get_lba_status function in the raw driver which >> adds the BDRV_BLOCK_RAW flag. bdrv_co_get_block_status will >> handle the callout to bs->file then. >> >> v4: use a flag to detect the raw driver instead of the strncmp >> hack >> >> block.c | 4 ++++ >> block/raw_bsd.c | 3 ++- >> include/block/block.h | 4 ++++ >> 3 files changed, 10 insertions(+), 1 deletion(-) >> >> diff --git a/block.c b/block.c >> index 93e113a..38a589e 100644 >> --- a/block.c >> +++ b/block.c >> @@ -3147,6 +3147,10 @@ static int64_t coroutine_fn bdrv_co_get_block_status(BlockDriverState *bs, >> return ret; >> } >> >> + if (ret & BDRV_BLOCK_RAW) { >> + return bdrv_get_block_status(bs->file, sector_num, nb_sectors, pnum); > > Strictly speaking, this should probably do something like this: > > assert(ret & BDRV_BLOCK_OFFSET_VALID); > return bdrv_get_block_status(bs->file, ret >> BDRV_SECTOR_BITS, > nb_sectors, pnum); > > Or alternatively the raw driver should return just "BDRV_BLOCK_RAW". > > As a third option, the raw driver could also return not just > BDRV_BLOCK_RAW and BDRV_BLOCK_OFFSET_VALID, but also BDRV_BLOCK_DATA (so > that the answer makes some sense even without going down to bs->file). > > But I'll let the block maintainers decide what to do. The return value is a bitfield, so let's use those bits and take Option 3. Stefan
On 07.10.2013 10:25, Paolo Bonzini wrote: > Il 07/10/2013 07:59, Peter Lieven ha scritto: >> if a raw device like an iscsi target or host device is used >> the current implementation makes a second call out to get >> the block status of bs->file. >> >> Signed-off-by: Peter Lieven <pl@kamp.de> >> --- >> v5: add a generic get_lba_status function in the raw driver which >> adds the BDRV_BLOCK_RAW flag. bdrv_co_get_block_status will >> handle the callout to bs->file then. >> >> v4: use a flag to detect the raw driver instead of the strncmp >> hack >> >> block.c | 4 ++++ >> block/raw_bsd.c | 3 ++- >> include/block/block.h | 4 ++++ >> 3 files changed, 10 insertions(+), 1 deletion(-) >> >> diff --git a/block.c b/block.c >> index 93e113a..38a589e 100644 >> --- a/block.c >> +++ b/block.c >> @@ -3147,6 +3147,10 @@ static int64_t coroutine_fn bdrv_co_get_block_status(BlockDriverState *bs, >> return ret; >> } >> >> + if (ret & BDRV_BLOCK_RAW) { >> + return bdrv_get_block_status(bs->file, sector_num, nb_sectors, pnum); > Strictly speaking, this should probably do something like this: > > assert(ret & BDRV_BLOCK_OFFSET_VALID); > return bdrv_get_block_status(bs->file, ret >> BDRV_SECTOR_BITS, > nb_sectors, pnum); shouldn't the last line be: return bdrv_get_block_status(bs->file, ret >> BDRV_SECTOR_BITS, *pnum, pnum); This would of course require *pnum = nb_sectors in raw_co_get_block_status ?
Il 08/10/2013 14:05, Peter Lieven ha scritto: >> Strictly speaking, this should probably do something like this: >> >> assert(ret & BDRV_BLOCK_OFFSET_VALID); >> return bdrv_get_block_status(bs->file, ret >> BDRV_SECTOR_BITS, >> nb_sectors, pnum); > shouldn't the last line be: > > return bdrv_get_block_status(bs->file, ret >> BDRV_SECTOR_BITS, > *pnum, pnum); > > > This would of course require *pnum = nb_sectors in raw_co_get_block_status > ? Yes for both questions. Paolo
diff --git a/block.c b/block.c index 93e113a..38a589e 100644 --- a/block.c +++ b/block.c @@ -3147,6 +3147,10 @@ static int64_t coroutine_fn bdrv_co_get_block_status(BlockDriverState *bs, return ret; } + if (ret & BDRV_BLOCK_RAW) { + return bdrv_get_block_status(bs->file, sector_num, nb_sectors, pnum); + } + if (!(ret & BDRV_BLOCK_DATA)) { if (bdrv_has_zero_init(bs)) { ret |= BDRV_BLOCK_ZERO; diff --git a/block/raw_bsd.c b/block/raw_bsd.c index d4ace60..308d605 100644 --- a/block/raw_bsd.c +++ b/block/raw_bsd.c @@ -62,7 +62,8 @@ static int64_t coroutine_fn raw_co_get_block_status(BlockDriverState *bs, int64_t sector_num, int nb_sectors, int *pnum) { - return bdrv_get_block_status(bs->file, sector_num, nb_sectors, pnum); + return BDRV_BLOCK_RAW | BDRV_BLOCK_OFFSET_VALID | + (sector_num << BDRV_SECTOR_BITS); } static int coroutine_fn raw_co_write_zeroes(BlockDriverState *bs, diff --git a/include/block/block.h b/include/block/block.h index f808550..003699e 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -84,6 +84,9 @@ typedef struct BlockDevOps { /* BDRV_BLOCK_DATA: data is read from bs->file or another file * BDRV_BLOCK_ZERO: sectors read as zero * BDRV_BLOCK_OFFSET_VALID: sector stored in bs->file as raw data + * BDRV_BLOCK_RAW: used internally to indicate that the request + * was answered by the raw driver and that one + * should look in bs->file directly. * * If BDRV_BLOCK_OFFSET_VALID is set, bits 9-62 represent the offset in * bs->file where sector data can be read from as raw data. @@ -105,6 +108,7 @@ typedef struct BlockDevOps { #define BDRV_BLOCK_DATA 1 #define BDRV_BLOCK_ZERO 2 #define BDRV_BLOCK_OFFSET_VALID 4 +#define BDRV_BLOCK_RAW 8 #define BDRV_BLOCK_OFFSET_MASK BDRV_SECTOR_MASK typedef enum {
if a raw device like an iscsi target or host device is used the current implementation makes a second call out to get the block status of bs->file. Signed-off-by: Peter Lieven <pl@kamp.de> --- v5: add a generic get_lba_status function in the raw driver which adds the BDRV_BLOCK_RAW flag. bdrv_co_get_block_status will handle the callout to bs->file then. v4: use a flag to detect the raw driver instead of the strncmp hack block.c | 4 ++++ block/raw_bsd.c | 3 ++- include/block/block.h | 4 ++++ 3 files changed, 10 insertions(+), 1 deletion(-)