From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:33654) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YsYIk-0004wA-Ag for qemu-devel@nongnu.org; Wed, 13 May 2015 11:10:31 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YsYIg-00028D-Tk for qemu-devel@nongnu.org; Wed, 13 May 2015 11:10:26 -0400 Message-ID: <55536950.4080808@redhat.com> Date: Wed, 13 May 2015 17:10:08 +0200 From: Max Reitz MIME-Version: 1.0 References: <1431105726-3682-1-git-send-email-kwolf@redhat.com> <1431105726-3682-28-git-send-email-kwolf@redhat.com> In-Reply-To: <1431105726-3682-28-git-send-email-kwolf@redhat.com> Content-Type: text/plain; charset=iso-8859-15; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 27/34] block: Add infrastructure for option inheritance List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Kevin Wolf , qemu-block@nongnu.org Cc: armbru@redhat.com, qemu-devel@nongnu.org On 08.05.2015 19:21, Kevin Wolf wrote: > Options are not actually inherited from the parent node yet, but this > commit lays the grounds for doing so. > > Signed-off-by: Kevin Wolf > --- > block.c | 51 ++++++++++++++++++++++++++--------------------- > include/block/block_int.h | 3 ++- > 2 files changed, 30 insertions(+), 24 deletions(-) > > diff --git a/block.c b/block.c > index 1e5625f..9259b42 100644 > --- a/block.c > +++ b/block.c > @@ -678,11 +678,14 @@ static int bdrv_temp_snapshot_flags(int flags) > } > > /* > - * Returns the flags that bs->file should get if a protocol driver is expected, > - * based on the given flags for the parent BDS > + * Returns the options and flags that bs->file should get if a protocol driver > + * is expected, based on the given flags for the parent BDS > */ > -static int bdrv_inherited_flags(int flags) > +static void bdrv_inherited_options(int *child_flags, QDict *child_options, > + int parent_flags, QDict *parent_options) > { > + int flags = parent_flags; > + > /* Enable protocol handling, disable format probing for bs->file */ > flags |= BDRV_O_PROTOCOL; > > @@ -693,45 +696,46 @@ static int bdrv_inherited_flags(int flags) > /* Clear flags that only apply to the top layer */ > flags &= ~(BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING | BDRV_O_COPY_ON_READ); > > - return flags; > + *child_flags = flags; > } > > const BdrvChildRole child_file = { > - .inherit_flags = bdrv_inherited_flags, > + .inherit_options = bdrv_inherited_options, > }; > > -/* > - * Returns the flags that bs->file should get if the use of formats (and not > - * only protocols) is permitted for it, based on the given flags for the parent > - * BDS > - */ Is removing this comment intentional? The rest looks fine. Max > -static int bdrv_inherited_fmt_flags(int parent_flags) > +static void bdrv_inherited_fmt_options(int *child_flags, QDict *child_options, > + int parent_flags, QDict *parent_options) > { > - int flags = child_file.inherit_flags(parent_flags); > - return flags & ~BDRV_O_PROTOCOL; > + child_file.inherit_options(child_flags, child_options, > + parent_flags, parent_options); > + > + *child_flags &= ~BDRV_O_PROTOCOL; > } > > const BdrvChildRole child_format = { > - .inherit_flags = bdrv_inherited_fmt_flags, > + .inherit_options = bdrv_inherited_fmt_options, > }; > > /* > - * Returns the flags that bs->backing_hd should get, based on the given flags > - * for the parent BDS > + * Returns the options and flags that bs->backing_hd should get, based on the > + * given options and flags for the parent BDS > */ > -static int bdrv_backing_flags(int flags) > +static void bdrv_backing_options(int *child_flags, QDict *child_options, > + int parent_flags, QDict *parent_options) > { > + int flags = parent_flags; > + > /* backing files always opened read-only */ > flags &= ~(BDRV_O_RDWR | BDRV_O_COPY_ON_READ); > > /* snapshot=on is handled on the top layer */ > flags &= ~(BDRV_O_SNAPSHOT | BDRV_O_TEMPORARY); > > - return flags; > + *child_flags = flags; > } > > static const BdrvChildRole child_backing = { > - .inherit_flags = bdrv_backing_flags, > + .inherit_options = bdrv_backing_options, > }; > > static int bdrv_open_flags(BlockDriverState *bs, int flags) > @@ -1407,7 +1411,8 @@ static int bdrv_open_inherit(BlockDriverState **pbs, const char *filename, > > if (child_role) { > bs->inherits_from = parent; > - flags = child_role->inherit_flags(parent->open_flags); > + child_role->inherit_options(&flags, options, > + parent->open_flags, parent->options); > } > > ret = bdrv_fill_options(&options, &filename, flags, drv, &local_err); > @@ -1445,7 +1450,7 @@ static int bdrv_open_inherit(BlockDriverState **pbs, const char *filename, > } > if (flags & BDRV_O_SNAPSHOT) { > snapshot_flags = bdrv_temp_snapshot_flags(flags); > - flags = bdrv_backing_flags(flags); > + bdrv_backing_options(&flags, options, flags, options); > } > > assert(file == NULL); > @@ -1645,14 +1650,14 @@ static BlockReopenQueue *bdrv_reopen_queue_child(BlockReopenQueue *bs_queue, > * 1. Explicitly passed in options (highest) > * 2. TODO Set in flags (only for top level) > * 3. TODO Retained from explicitly set options of bs > - * 4. TODO Inherited from parent node > + * 4. Inherited from parent node > * 5. Retained from effective options of bs > */ > > /* Inherit from parent node */ > if (parent_options) { > assert(!flags); > - flags = role->inherit_flags(parent_flags); > + role->inherit_options(&flags, options, parent_flags, parent_options); > } > > /* Old values are used for options that aren't set yet */ > diff --git a/include/block/block_int.h b/include/block/block_int.h > index c9333b2..1cae8d4 100644 > --- a/include/block/block_int.h > +++ b/include/block/block_int.h > @@ -328,7 +328,8 @@ typedef struct BdrvAioNotifier { > } BdrvAioNotifier; > > struct BdrvChildRole { > - int (*inherit_flags)(int parent_flags); > + void (*inherit_options)(int *child_flags, QDict *child_options, > + int parent_flags, QDict *parent_options); > }; > > extern const BdrvChildRole child_file;