The caller will not undo a mapping which failed and therefore the
override will not be removed.
This is especially bad in the case of GNTMAP_contains_pte mapping type
mappings where m2p_add_override will destroy the kernel mapping of the
page.
This was observed via a failure of map_grant_pages in gntdev_mmap (due
to userspace using a bad grant reference), which left the page in
question unmapped (because it was a GNTMAP_contains_pte mapping) which
led to a crash later on.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The handle with numeric value 0 is a valid map handle, so it cannot
be used to indicate that a page has not been mapped. Use -1 instead.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
When CONFIG_XEN is enabled the gntdev and gntalloc driver will be
compiled as a module by default.
[v2: Added the fix for the gntalloc driver as well]
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
If an already-mapped area of the device was mapped into userspace a
second time, a hypercall was incorrectly made to remap the memory
again. Avoid the hypercall on later mmap calls, and fail the mmap call
if a writable mapping is attempted on a read-only range.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
In paravirtualized domains, mn_invl_page or mn_invl_range_start can
unmap a segment of a mapped region without unmapping all pages. When
the region is later released, the pages will be unmapped twice, leading
to an incorrect -EINVAL return.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The is_mapped flag used to be set at the completion of the map operation,
but was not checked in all error paths. Use map->vma instead, which will
now be cleared if the initial grant mapping fails.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
In paravirtualized guests, the struct page* for mappings is only a
placeholder, and cannot be used to access the granted memory. Use the
userspace mapping that we have set up in order to implement
UNMAP_NOTIFY_CLEAR_BYTE.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The error path did not decrement the reference count of the grant structure.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This ioctl allows the users of a shared page to be notified when
the other end exits abnormally.
[v2: updated description in structs]
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This allows a userspace application to allocate a shared page for
implementing inter-domain communication or device drivers. These
shared pages can be mapped using the gntdev device or by the kernel
in another domain.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
HVM does not allow direct PTE modification, so instead we request
that Xen change its internal p2m mappings on the allocated pages and
map the memory into userspace normally.
Note:
The HVM path for map and unmap is slightly different: HVM keeps the pages
mapped until the area is deleted, while the PV case (use_ptemod being true)
must unmap them when userspace unmaps the range. In the normal use case,
this makes no difference to users since unmap time is deletion time.
[v2: Expanded commit descr.]
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This allows userspace to perform mmap() on the gntdev device and then
immediately close the filehandle or remove the mapping using the
remove ioctl, with the mapped area remaining valid until unmapped.
This also fixes an infinite loop when a gntdev device is closed
without first unmapping all areas.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This should be faster if many mappings exist, and also removes
the only user of map->vma not related to PTE modification.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Because there is no limitation on how many times a user can open a
given device file, an per-file-description limit on the number of
pages granted offers little to no benefit. Change to a global limit
and remove the ioctl() as the parameter can now be changed via sysfs.
Xen tools changeset 22768:f8d801e5573e is needed to eliminate the
error this change produces in xc_gnttab_set_max_grants.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
lockdep, timer: Fix del_timer_sync() annotation
RTC: Prevents a division by zero in kernel code.
FREQ is a ridiculously short name for a platform-specific macro in a
generic header, and it now conflicts with an enumeration in the
gspca/ov519 driver.
Also delete conditional reference to ixp4xx_get_board_tick_rate()
which is not defined anywhere.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Krzysztof Hałasa <khc@pm.waw.pl>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (68 commits)
net: can: janz-ican3: world-writable sysfs termination file
net: can: at91_can: world-writable sysfs files
MAINTAINERS: update email ids of the be2net driver maintainers.
bridge: Don't put partly initialized fdb into hash
r8169: prevent RxFIFO induced loops in the irq handler.
r8169: RxFIFO overflow oddities with 8168 chipsets.
r8169: use RxFIFO overflow workaround for 8168c chipset.
include/net/genetlink.h: Allow genlmsg_cancel to accept a NULL argument
net: Provide compat support for SIOCGETMIFCNT_IN6 and SIOCGETSGCNT_IN6.
net: Support compat SIOCGETVIFCNT ioctl in ipv4.
net: Fix bug in compat SIOCGETSGCNT handling.
niu: Fix races between up/down and get_stats.
tcp_ecn is an integer not a boolean
atl1c: Add missing PCI device ID
s390: Fix possibly wrong size in strncmp (smsgiucv)
s390: Fix wrong size in memcmp (netiucv)
qeth: allow OSA CHPARM change in suspend state
qeth: allow HiperSockets framesize change in suspend
qeth: add more strict MTU checking
qeth: show new mac-address if its setting fails
...
Don't allow everybody to set terminator via sysfs.
Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6: (27 commits)
gpu/stub: fix acpi_video build error, fix stub kconfig dependencies
drm/radeon/kms: dynamically allocate power state space
drm/radeon/kms: fix s/r issues with bios scratch regs
agp: ensure GART has an address before enabling it
Revert "agp: AMD AGP is used on UP1100 & UP1500 alpha boxen"
amd-k7-agp: remove non-x86 code
drm/radeon/kms/evergreen: always set certain VGT regs at CP init
drm/radeon/kms: add updated ib_execute function for evergreen
drm/radeon: remove 0x4243 pci id
drm/radeon/kms: Enable new pll calculation for avivo+ asics
drm/radeon/kms: add new pll algo for avivo asics
drm/radeon/kms: add pll debugging output
drm/radeon/kms: switch back to min->max pll post divider iteration
drm/radeon/kms: rv6xx+ thermal sensor fixes
drm/nv50: fix display on 0x50
drm/nouveau: correctly pair hwmon_init and hwmon_fini
drm/i915: Only bind to function 0 of the PCI device
drm/i915: Suppress spurious vblank interrupts
drm: Avoid leak of adjusted mode along quick set_mode paths
drm: Simplify and defend later checks when disabling a crtc
...
While the RxFIFO interruption is masked for most 8168, nothing prevents
it to appear in the irq status word. This is no excuse to crash.
Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
Cc: Ivan Vecera <ivecera@redhat.com>
Cc: Hayes <hayeswang@realtek.com>
Ian Campbell
Daniel De Graaf
Stefano Stabellini
Linus Torvalds
Ben Hutchings
Vasiliy Kulikov
Keith Packard
Francois Romieu