This patch is the folded version of API updates, along with the associated tool
changes to ensure that the build is always consistent.
API updates:
- The source domain in the sharing calls is no longer assumed to be dom0.
- Previously, the mem sharing code would return an opaque handle to index
shared pages (and nominees) in its global hash table. By removing the hash
table, the handle becomes a version, to avoid sharing a stale version of a
page. Thus, libxc wrappers and tools need to be updated to recall the share
functions with the information needed to fetch the page (which they readily
have).
Tool updates:
The only (in-tree, that we know of) consumer of the mem sharing API is the
memshr tool. This is updated to use the new API.
Signed-off-by: Andres Lagar-Cavilla <andres@lagarcavilla.org>
Signed-off-by: Adin Scannell <adin@scannell.ca>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Tim Deegan <tim@xen.org>
This patch addresses some of the compile and link issues with the memshr
module.
Signed-off-by: Adin Scannell <adin@scannell.ca>
Signed-off-by: Andres Lagar-Cavilla <andres@lagarcavilla.org>
Acked-by: Ian Jackson <ian.jackson.citrix.com>
Committed-by: Ian Jackson <ian.jackson.citrix.com>
detect sharable memory pages). This patch establishes unique id for each disk
image opened by tapdisk2, and stores it in shared memory region, thus making it
available to the remaining tapdisk2s.
Signed-off-by: Grzegorz Milos <Grzegorz.Milos@citrix.com>
the tapdisk2 process if sharing is enabled (tapdisk2 is not normally aware what
domain it is working for).
Signed-off-by: Grzegorz Milos <Grzegorz.Milos@citrix.com>
a single map is used to store mappings between sharing handles and disk blocks.
This is used to share pages which store data read of the same blocks on
(virtual) disk.
Note that the map is stored in a shared memory region, as it needs to be
accessed by multiple tapdisk processes. This complicates memory allocation
(malloc cannot be used), prevents poniters to be stored directly (as the shared
memory region might and is mapped at different base address) and finally pthread
locks need to be multi-process aware.
Signed-off-by: Grzegorz Milos <Grzegorz.Milos@citrix.com>
Andres Lagar-Cavilla
Keir Fraser