On 22/09/2020 18.16, Daniel P. Berrangé wrote: Reviewed-by: Thomas Huth <thuth(a)redhat.com&gt;

This thread from a little over a year ago: http://lists.wpkg.org/pipermail/sheepdog/2019-March/thread.html states that sheepdog is no longer actively developed. The only mentioned users are some companies who are said to have it for legacy reasons with plans to replace it by Ceph. There is talk about cutting out existing features to turn it into a simple demo of how to write a distributed block service. There is no evidence of anyone working on that idea: https://github.com/sheepdog/sheepdog/commits/master No real commits to git since Jan 2018, and before then just some minor technical debt cleanup.. There is essentially no activity on the mailing list aside from patches to QEMU that get CC'd due to our MAINTAINERS entry. Fedora packages for sheepdog failed to build from upstream source because of the more strict linker that no longer merges duplicate global symbols. Fedora patches it to add the missing "extern" annotations and presumably other distros do to, but upstream source remains broken. There is only basic compile testing, no functional testing of the driver. Since there are no build pre-requisites the sheepdog driver is currently enabled unconditionally. This would result in configure issuing a deprecation warning by default for all users. Thus the configure default is changed to disable it, requiring users to pass --enable-sheepdog to build the driver. Signed-off-by: Daniel P. Berrangé <berrange(a)redhat.com&gt; --- block/sheepdog.c | 15 +++++++++++++++ configure | 5 +++-- docs/system/deprecated.rst | 9 +++++++++ 3 files changed, 27 insertions(+), 2 deletions(-) diff --git a/block/sheepdog.c b/block/sheepdog.c index cbbebc1aaf..7f68bd6a1a 100644 --- a/block/sheepdog.c +++ b/block/sheepdog.c @@ -242,6 +242,17 @@ typedef struct SheepdogInode { */ #define FNV1A_64_INIT ((uint64_t)0xcbf29ce484222325ULL) +static void deprecation_warning(void) +{ + static bool warned = false; + + if (!warned) { + warn_report("the sheepdog block driver is deprecated and will be " + "removed in a future release"); + warned = true; + } +} + /* * 64 bit Fowler/Noll/Vo FNV-1a hash code */ @@ -1548,6 +1559,8 @@ static int sd_open(BlockDriverState *bs, QDict *options, int flags, char *buf = NULL; QemuOpts *opts; + deprecation_warning(); + s->bs = bs; s->aio_context = bdrv_get_aio_context(bs); @@ -2007,6 +2020,8 @@ static int sd_co_create(BlockdevCreateOptions *options, Error **errp) assert(options->driver == BLOCKDEV_DRIVER_SHEEPDOG); + deprecation_warning(); + s = g_new0(BDRVSheepdogState, 1); /* Steal SocketAddress from QAPI, set NULL to prevent double free */ diff --git a/configure b/configure index 7564479008..c6af83f2e6 100755 --- a/configure +++ b/configure @@ -533,7 +533,7 @@ vdi="yes" vvfat="yes" qed="yes" parallels="yes" -sheepdog="yes" +sheepdog="no" libxml2="" debug_mutex="no" libpmem="" @@ -1941,7 +1941,7 @@ disabled with --disable-FEATURE, default is enabled if available: vvfat vvfat image format support qed qed image format support parallels parallels image format support - sheepdog sheepdog block driver support + sheepdog sheepdog block driver support (deprecated) crypto-afalg Linux AF_ALG crypto backend driver capstone capstone disassembler support debug-mutex mutex debugging support @@ -7350,6 +7350,7 @@ if test "$parallels" = "yes" ; then echo "CONFIG_PARALLELS=y" >> $config_host_mak fi if test "$sheepdog" = "yes" ; then + add_to deprecated_features "sheepdog" echo "CONFIG_SHEEPDOG=y" >> $config_host_mak fi if test "$pty_h" = "yes" ; then diff --git a/docs/system/deprecated.rst b/docs/system/deprecated.rst index 0cb8b01424..49b9f4b02e 100644 --- a/docs/system/deprecated.rst +++ b/docs/system/deprecated.rst @@ -405,6 +405,15 @@ The above, converted to the current supported format:: json:{"file.driver":"rbd", "file.pool":"rbd", "file.image":"name"} +``sheepdog`` driver (since 5.2.0) +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +The ``sheepdog`` block device driver is deprecated. The corresponding upstream +server project is no longer actively maintained. Users are recommended to switch +to an alternative distributed block device driver such as RBD. The +``qemu-img convert`` command can be used to liberate existing data by moving +it out of sheepdog volumes into an alternative storage backend. + linux-user mode CPUs -------------------- -- 2.26.2

Daniel P. Berrangé <berrange(a)redhat.com&gt; writes: Drop the extra period. Obey checkpatch :) Similar warnings elsewhere don't say "will be removed". Some of them are nice enough to advise what to use instead, but that may not be practical here. Preferably with my nits addressed: Reviewed-by: Markus Armbruster <armbru(a)redhat.com&gt;