| Message ID | 1340377726-5896-3-git-send-email-stefanha@linux.vnet.ibm.com |
|---|---|
| State | New |
| Headers | show |
Am 22.06.2012 17:08, schrieb Stefan Hajnoczi: > This patch adds an incompatible feature bit to mark images that have not > been closed cleanly. When a dirty image file is opened a consistency > check and repair is performed. > > Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> > --- > block/qcow2.c | 44 ++++++++++++++++++++++++++++++++++++++++++-- > block/qcow2.h | 3 +++ > 2 files changed, 45 insertions(+), 2 deletions(-) > diff --git a/block/qcow2.h b/block/qcow2.h > index 455b6d7..5c7cfb6 100644 > --- a/block/qcow2.h > +++ b/block/qcow2.h > @@ -108,6 +108,9 @@ enum { > QCOW2_FEAT_TYPE_INCOMPATIBLE = 0, > QCOW2_FEAT_TYPE_COMPATIBLE = 1, > QCOW2_FEAT_TYPE_AUTOCLEAR = 2, > + > + QCOW2_INCOMPATIBLE_FEAT_DIRTY = 0x1, > + QCOW2_INCOMPATIBLE_FEAT_MASK = QCOW2_INCOMPATIBLE_FEAT_DIRTY, > }; I would use a separate enum for each of the three flag categories. Also, you should add a feature table entry for the dirty bit so that older qemu versions can display a useful error message. Kevin
On Mon, Jun 25, 2012 at 3:18 PM, Kevin Wolf <kwolf@redhat.com> wrote: > Am 22.06.2012 17:08, schrieb Stefan Hajnoczi: >> This patch adds an incompatible feature bit to mark images that have not >> been closed cleanly. When a dirty image file is opened a consistency >> check and repair is performed. >> >> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> >> --- >> block/qcow2.c | 44 ++++++++++++++++++++++++++++++++++++++++++-- >> block/qcow2.h | 3 +++ >> 2 files changed, 45 insertions(+), 2 deletions(-) > >> diff --git a/block/qcow2.h b/block/qcow2.h >> index 455b6d7..5c7cfb6 100644 >> --- a/block/qcow2.h >> +++ b/block/qcow2.h >> @@ -108,6 +108,9 @@ enum { >> QCOW2_FEAT_TYPE_INCOMPATIBLE = 0, >> QCOW2_FEAT_TYPE_COMPATIBLE = 1, >> QCOW2_FEAT_TYPE_AUTOCLEAR = 2, >> + >> + QCOW2_INCOMPATIBLE_FEAT_DIRTY = 0x1, >> + QCOW2_INCOMPATIBLE_FEAT_MASK = QCOW2_INCOMPATIBLE_FEAT_DIRTY, >> }; > > I would use a separate enum for each of the three flag categories. > > Also, you should add a feature table entry for the dirty bit so that > older qemu versions can display a useful error message. Good point, I forgot to do this. Stefan
diff --git a/block/qcow2.c b/block/qcow2.c index 2c1cd0a..cc30784 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -214,6 +214,27 @@ static void report_unsupported_feature(BlockDriverState *bs, } } +/* + * Clears the dirty bit and flushes before if necessary. Only call this + * function when there are no pending requests, it does not guard against + * concurrent requests dirtying the image. + */ +static int qcow2_mark_clean(BlockDriverState *bs) +{ + BDRVQcowState *s = bs->opaque; + + if (s->incompatible_features & QCOW2_INCOMPATIBLE_FEAT_DIRTY) { + int ret = bdrv_flush(bs); + if (ret < 0) { + return ret; + } + + s->incompatible_features &= ~QCOW2_INCOMPATIBLE_FEAT_DIRTY; + return qcow2_update_header(bs); + } + return 0; +} + static int qcow2_open(BlockDriverState *bs, int flags) { BDRVQcowState *s = bs->opaque; @@ -287,12 +308,13 @@ static int qcow2_open(BlockDriverState *bs, int flags) s->compatible_features = header.compatible_features; s->autoclear_features = header.autoclear_features; - if (s->incompatible_features != 0) { + if (s->incompatible_features & ~QCOW2_INCOMPATIBLE_FEAT_MASK) { void *feature_table = NULL; qcow2_read_extensions(bs, header.header_length, ext_end, &feature_table); report_unsupported_feature(bs, feature_table, - s->incompatible_features); + s->incompatible_features & + ~QCOW2_INCOMPATIBLE_FEAT_MASK); ret = -ENOTSUP; goto fail; } @@ -412,6 +434,22 @@ static int qcow2_open(BlockDriverState *bs, int flags) /* Initialise locks */ qemu_co_mutex_init(&s->lock); + /* Repair image if dirty */ + if ((s->incompatible_features & QCOW2_INCOMPATIBLE_FEAT_DIRTY) && + !bs->read_only) { + BdrvCheckResult result = {0}; + + ret = qcow2_check_refcounts(bs, &result, BDRV_FIX_ERRORS); + if (ret < 0) { + goto fail; + } + + ret = qcow2_mark_clean(bs); + if (ret < 0) { + goto fail; + } + } + #ifdef DEBUG_ALLOC { BdrvCheckResult result = {0}; @@ -788,6 +826,8 @@ static void qcow2_close(BlockDriverState *bs) qcow2_cache_flush(bs, s->l2_table_cache); qcow2_cache_flush(bs, s->refcount_block_cache); + qcow2_mark_clean(bs); + qcow2_cache_destroy(bs, s->l2_table_cache); qcow2_cache_destroy(bs, s->refcount_block_cache); diff --git a/block/qcow2.h b/block/qcow2.h index 455b6d7..5c7cfb6 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -108,6 +108,9 @@ enum { QCOW2_FEAT_TYPE_INCOMPATIBLE = 0, QCOW2_FEAT_TYPE_COMPATIBLE = 1, QCOW2_FEAT_TYPE_AUTOCLEAR = 2, + + QCOW2_INCOMPATIBLE_FEAT_DIRTY = 0x1, + QCOW2_INCOMPATIBLE_FEAT_MASK = QCOW2_INCOMPATIBLE_FEAT_DIRTY, }; typedef struct Qcow2Feature {
This patch adds an incompatible feature bit to mark images that have not been closed cleanly. When a dirty image file is opened a consistency check and repair is performed. Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> --- block/qcow2.c | 44 ++++++++++++++++++++++++++++++++++++++++++-- block/qcow2.h | 3 +++ 2 files changed, 45 insertions(+), 2 deletions(-)