The notify offset and event channels are both unsigned variables, so
testing for >= 0 will not correctly detect the use of -1 to indicate
the field is unused. Remove the useless comparison and replace with
correct range checks or comparisons to -1.
Reported-by: Anil Madhavapeddy <anil@recoil.org>
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
Move (page aligned) buffer allocations in {os}_privcmd_alloc_hypercall_buffer
into a global function xc_memalign. This API is also used by Remus
compression code to allocate compression caches that need to be page aligned.
Signed-off-by: Shriram Rajagopalan <rshriram@cs.ubc.ca>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Brendan Cully <brendan@cs.ubc.ca>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
These functions and the xc_gntshr device (/dev/xen/gntalloc on linux)
allow applications to create pages shared with other domains.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
Normally, when a userspace process mapping a grant crashes, the domain
providing the reference receives no indication that its peer has
crashed, possibly leading to unexpected freezes or timeouts. This
function provides a notification of the unmap by signalling an event
channel and/or clearing a specific byte in the page.
This also unifies the 3 very similar grant-mapping osdep interfaces into
a single function instead of introducing yet another minor variation.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
This will allow us to use OS specific interfaces to ensure that the
allocated memory is safe for use as a hypercall buffer in the future.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
The maximum number of grants is now constrained domain-wide in linux,
so set_max_grants should be a noop there. Previously, this constraint
was per-file-description.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
This helps ensure that the osdep abstraction is complete by
allowing us to avoid including xc_private.h.
All the other OS backends could benefit from the same treatment but
since I cannot compile test I did not do this.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Ian Jackson <ian.jackson.citrix.com>
Daniel De Graaf
Shriram Rajagopalan
Ian Campbell