Add a dentry op (d_automount) to handle automounting directories rather than
abusing the follow_link() inode operation. The operation is keyed off a new
dentry flag (DCACHE_NEED_AUTOMOUNT).
This also makes it easier to add an AT_ flag to suppress terminal segment
automount during pathwalk and removes the need for the kludge code in the
pathwalk algorithm to handle directories with follow_link() semantics.
The ->d_automount() dentry operation:
struct vfsmount *(*d_automount)(struct path *mountpoint);
takes a pointer to the directory to be mounted upon, which is expected to
provide sufficient data to determine what should be mounted. If successful, it
should return the vfsmount struct it creates (which it should also have added
to the namespace using do_add_mount() or similar). If there's a collision with
another automount attempt, NULL should be returned. If the directory specified
by the parameter should be used directly rather than being mounted upon,
-EISDIR should be returned. In any other case, an error code should be
returned.
The ->d_automount() operation is called with no locks held and may sleep. At
this point the pathwalk algorithm will be in ref-walk mode.
Within fs/namei.c itself, a new pathwalk subroutine (follow_automount()) is
added to handle mountpoints. It will return -EREMOTE if the automount flag was
set, but no d_automount() op was supplied, -ELOOP if we've encountered too many
symlinks or mountpoints, -EISDIR if the walk point should be used without
mounting and 0 if successful. The path will be updated to point to the mounted
filesystem if a successful automount took place.
__follow_mount() is replaced by follow_managed() which is more generic
(especially with the patch that adds ->d_manage()). This handles transits from
directories during pathwalk, including automounting and skipping over
mountpoints (and holding processes with the next patch).
__follow_mount_rcu() will jump out of RCU-walk mode if it encounters an
automount point with nothing mounted on it.
follow_dotdot*() does not handle automounts as you don't want to trigger them
whilst following "..".
I've also extracted the mount/don't-mount logic from autofs4 and included it
here. It makes the mount go ahead anyway if someone calls open() or creat(),
tries to traverse the directory, tries to chdir/chroot/etc. into the directory,
or sticks a '/' on the end of the pathname. If they do a stat(), however,
they'll only trigger the automount if they didn't also say O_NOFOLLOW.
I've also added an inode flag (S_AUTOMOUNT) so that filesystems can mark their
inodes as automount points. This flag is automatically propagated to the
dentry as DCACHE_NEED_AUTOMOUNT by __d_instantiate(). This saves NFS and could
save AFS a private flag bit apiece, but is not strictly necessary. It would be
preferable to do the propagation in d_set_d_op(), but that doesn't normally
have access to the inode.
[AV: fixed breakage in case if __follow_mount_rcu() fails and nameidata_drop_rcu()
succeeds in RCU case of do_lookup(); we need to fall through to non-RCU case after
that, rather than just returning with ungrabbed *path]
Signed-off-by: David Howells <dhowells@redhat.com>
Was-Acked-by: Ian Kent <raven@themaw.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
do_lookup() has a path leading from LOOKUP_RCU case to non-RCU
crossing of mountpoints, which breaks things badly. If we
hit need_revalidate: and do nothing in there, we need to come
back into LOOKUP_RCU half of things, not to done: in non-RCU
one.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* 'slab/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6:
Update Pekka's email address in MAINTAINERS
mm/slab.c: make local symbols static
slub: Avoid use of slub_lock in show_slab_objects()
memory hotplug: one more lock on memory hotplug
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
rcu: avoid pointless blocked-task warnings
rcu: demote SRCU_SYNCHRONIZE_DELAY from kernel-parameter status
rtmutex: Fix comment about why new_owner can be NULL in wake_futex_pi()
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, olpc: Add missing Kconfig dependencies
x86, mrst: Set correct APB timer IRQ affinity for secondary cpu
x86: tsc: Fix calibration refinement conditionals to avoid divide by zero
x86, ia64, acpi: Clean up x86-ism in drivers/acpi/numa.c
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
timekeeping: Make local variables static
time: Rename misnamed minsec argument of clocks_calc_mult_shift()
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
tracing: Remove syscall_exit_fields
tracing: Only process module tracepoints once
perf record: Add "nodelay" mode, disabled by default
perf sched: Fix list of events, dropping unsupported ':r' modifier
Revert "perf tools: Emit clearer message for sys_perf_event_open ENOENT return"
perf top: Fix annotate segv
perf evsel: Fix order of event list deletion
* 'fixes' of master.kernel.org:/home/rmk/linux-2.6-arm:
ARM: fix missing branch in __error_a
ARM: fix /proc/$PID/stack on SMP
ARM: Fix build regression on SA11x0, PXA, and H720x targets
ARM: 6625/1: use memblock memory regions for "System RAM" I/O resources
ARM: fix wrongly patched constants
ARM: 6624/1: fix dependency for CONFIG_SMP_ON_UP
ARM: 6623/1: Thumb-2: Fix out-of-range offset for Thumb-2 in proc-v7.S
ARM: 6622/1: fix dma_unmap_sg() documentation
ARM: 6621/1: bitops: remove condition code clobber for CLZ
ARM: 6620/1: Change misleading warning when CONFIG_CMDLINE_FORCE is used
ARM: 6619/1: nommu: avoid mapping vectors page when !CONFIG_MMU
ARM: sched_clock: make minsec argument to clocks_calc_mult_shift() zero
ARM: sched_clock: allow init_sched_clock() to be called early
ARM: integrator: fix compile warning in cpu.c
ARM: 6616/1: Fix ep93xx-fb init/exit annotations
ARM: twd: fix display of twd frequency
ARM: udelay: prevent math rounding resulting in short udelays
on Parisc, we have an include of linux/mm.h inside our asm/pgtable.h, so
this patch
commit 14fd403f21
Author: Andrea Arcangeli <aarcange@redhat.com>
Date: Thu Jan 13 15:46:37 2011 -0800
thp: export maybe_mkwrite
Causes us an unsatisfiable use of pte_mkwrite in linux/mm.h
The fix is obviously not to include linux/mm.h in our pgtable.h, which
unbreaks the build.
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Remove the broken line wrapping handling in pdc_iodc_print().
It is broken in 3 ways :
- It doesn't keep track of the current screen position, it just
assumes that the new buffer will be printed at the begining of the
screen.
- It doesn't take in account that non printable characters won't
increase the current position on the screen.
- And last but not least, it triggers a kernel panic if a backspace
is the first char in the provided buffer :
Backtrace:
[<0000000040128ec4>] pdc_console_write+0x44/0x78
[<0000000040128f18>] pdc_console_tty_write+0x20/0x38
[<000000004032f1ac>] n_tty_write+0x2a4/0x550
[<000000004032b158>] tty_write+0x1e0/0x2d8
[<00000000401bb420>] vfs_write+0xb8/0x188
[<00000000401bb630>] sys_write+0x68/0xb8
[<0000000040104eb8>] syscall_exit+0x0/0x14
Most terminals handle the line wrapping just fine. I've confirmed that
it works correctly on a C8000 with both vga and serial output.
Signed-off-by: Guy Martin <gmsoft@tuxicoman.be>
Cc: Stable Tree <stable@kernel.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Local symbols should be static.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
When DEBUG_LL is not set, we don't want __error_a re-entering
__lookup_machine_type - we want it to go to the error function. This
used to be the case before we reorganized the layout for hotplug cpu,
as we used to fall through to __error. With the changed layout, we
need an explicit branch here instead.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Drive strength for PXA910 is a 2 bit value but because of the mapping in
plat-pxa/mfp.h needs to be shifted up one bit to handle real
location in mfp registers. (MMP2 and PXA910 drive strength start
at bit 11 while PXA168 starts at bit 10).
Values 0, 1, 2, and 3 effectively need to be
0, 2, 4, and 6 to fit into register. 8 does not work.
Signed-off-by: Philip Rakity <prakity@marvell.com>
Signed-off-by: Eric Miao <eric.y.miao@gmail.com>
Drive strength for MMP2 is a 2 bit value but because of the mapping in
plat-pxa/mfp.h needs to be shifted up one bit to handle real
location in mfp registers. (MMP2 and PXA910 drive strength start
at bit 11 while PXA168 starts at bit 10).
Values 0, 1, 2, and 3 effectively need to be
0, 2, 4, and 6 to fit into register. 8 does not work.
Signed-off-by: Philip Rakity <prakity@marvell.com>
Tested-by: John Watlington <wad@laptop.org>
Signed-off-by: Eric Miao <eric.y.miao@gmail.com>
Rabin Vincent reports:
| On SMP, this BUG() in save_stack_trace_tsk() can be easily triggered
| from user space by reading /proc/$PID/stack, where $PID is any pid but
| the current process:
|
| if (tsk != current) {
| #ifdef CONFIG_SMP
| /*
| * What guarantees do we have here that 'tsk'
| * is not running on another CPU?
| */
| BUG();
| #else
Fix this by replacing the BUG() with an entry to terminate the stack
trace, returning an empty trace - I'd rather not expose the dwarf
unwinder to a volatile stack of a running thread.
Reported-by: Rabin Vincent <rabin@rab.in>
Tested-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Commit f5e70d0fe3 renamed MD_RAID6_PQ to RAID6_PQ,
but iop-adma.c didn't update synchronously.
Signed-off-by: Wei Yongquan <weiyqlq@gmail.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
drivers/dma/amba-pl08x.c: In function 'pl08x_start_txd':
drivers/dma/amba-pl08x.c:205: warning: dereferencing 'void *' pointer
We never dereference llis_va aside from assigning it to a struct
pl08x_lli pointer or calculating the address of array element 0.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
desc->tx_submit's return type is dma_cookie_t, not int. Therefore,
dmaengine_submit() should match this return type as it's just
wrapping this detail.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
We were reading channel status then taking a lock. This lead to a race because
this lock may delay us and then make this channel not idle anymore.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Place flags on first descriptor of chain instead of last.
This is the one used by atc_chain_complete() function while unmapping.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Use subsys_initcall instead of module_init in order to keep DMA engine rolling
before other peripheral drivers.
Signed-off-by: Eric Xu <hong.xu@atmel.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Following descriptor flow in at_hdmac driver, descriptor comming from
atc_desc_get() as already DMA_CTRL_ACK flag set. No need to set it again.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In atc_prep_slave_sg() function we use dma_address field of scatterlist with
sg_dma_address() macro instead of sg_phys(). DMA address is already computed
by dma_map_sg() or another mapping function in calling driver.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Support new device OKI SEMICONDUCTOR's ML7213 IOH(Input/Output Hub) which is for
IVI(In-Vehicle Infotainment) use.
The ML7213 is companion chip for Intel Atom E6xx series.
The ML7213 is completely compatible for Intel EG20T PCH.
Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Build errors similar this appeared in todays kautobuild for the above
targets:
In file included from arch/arm/include/asm/pgtable.h:461,
from arch/arm/mach-pxa/generic.c:26:
include/asm-generic/pgtable.h: In function 'ptep_test_and_clear_young':
include/asm-generic/pgtable.h:29: error: dereferencing pointer to incomplete type
None of the .c files including asm/pgtable.h with this error is using
this header, so simply remove the include.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This reverts commit dfe63bb0ad.
This commit was causing nouveau not to work properly, for -rc1 I'd
prefer it worked and we can look if this is useful for 2.6.39.
Cc: James Simmons <jsimmons@infradead.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The unused space in the doorbell is now marked as RsvdZ, not RsvdP, so
we can avoid reading the doorbell before writing it.
Update the doorbell-related defines to produce the entire doorbell value
from a single macro. Document the doorbell format in a comment.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
dev_dbg() is used to print ordinary transfer messages in xhci-ring.c.
System log messages will be flushed if CONFIG_USB_DEBUG is set. Replace the
dev_dbg() with xhci_dbg().
Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
giveback_first_trb() controls the cycle bit set of the start_trb, to ensure
that the start_trb is written last and the host controller will receive a
whole td at a time.
However, if the ring is wrapped and cycle bit is toggled to zero, then
giveback_first_trb() will be of no effect. In this case, set the cycle bit of
start_trb to 1 at the beginning and clear it in giveback_first_trb().
Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Parameter *td is not used in giveback_first_trb(). Remove it.
Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Fix the more_trbs_coming field of queue_trb() in isoc transfer.
Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
When xhci_discover_or_reset_device() is called after a host controller
power loss, the virtual device may need to be reallocated. Make sure
xhci_alloc_dev() uses GFP_NOIO. This avoid causing a deadlock by allowing
the kernel to flush pending I/O while reallocating memory for a virtual
device for a USB mass storage device that's holding the backing store for
dirty memory buffers.
This patch should be queued for the 2.6.37 stable tree.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@kernel.org
When there's an xHCI host power loss after a suspend from memory, the USB
core attempts to reset and verify the USB devices that are attached to the
system. The xHCI driver has to reallocate those devices, since the
hardware lost all knowledge of them during the power loss.
When a hub is plugged in, and the host loses power, the xHCI hardware
structures are not updated to say the device is a hub. This is usually
done in hub_configure() when the USB hub is detected. That function is
skipped during a reset and verify by the USB core, since the core restores
the old configuration and alternate settings, and the hub driver has no
idea this happened. This bug makes the xHCI host controller reject the
enumeration of low speed devices under the resumed hub.
Therefore, make the USB core re-setup the internal xHCI hub device
information by calling update_hub_device() when hub_activate() is called
for a hub reset resume. After a host power loss, all devices under the
roothub get a reset-resume or a disconnect.
This patch should be queued for the 2.6.37 stable tree.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@kernel.org
Synchronize the interrupts instead of free them in xhci_suspend(). This will
prevent a double free when the host is suspended and then the card removed.
Set the flag hcd->msix_enabled when using MSI-X, and check the flag in
suspend_common(). MSI-X synchronization will be handled by xhci_suspend(),
and MSI/INTx will be synchronized in suspend_common().
This patch should be queued for the 2.6.37 stable tree.
Reported-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@kernel.org
The original code that resumed the USB bus on a port status change would
only do so when there was a device connected to the port. If a device was
just disconnected, the event would be queued for khubd, but khubd wouldn't
run. That would leave the connect status change (CSC) bit set.
If a USB device was plugged into that same port, the xHCI host controller
would set the current connect status (CCS) bit. But since the CSC bit was
already set, it would not generate an interrupt for a port status change
event. That would mean the user could "Safely Remove" a device, have the
bus suspend, disconnect the device, re-plug it in, and then the device
would never be enumerated.
Plugging in a different device on another port would cause the bus to
resume, and khubd would notice the re-connected device. Running lsusb
would also resume the bus, leading users to report the problem "went away"
when using diagnostic tools.
The solution is to resume the bus when a port status change event is
received, regardless of the port status.
Thank you very much to Maddog for helping me track down this Heisenbug.
This patch should be queued for the 2.6.37 stable tree.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Reported-by: Jon 'maddog' Hall <maddog@li.org>
Tested-by: Andiry Xu <andiry.xu@amd.com>
Cc: stable@kernel.org
* 'next-spi' of git://git.secretlab.ca/git/linux-2.6:
spi/amba-pl022: fixing compilation warning.
spi: Enable SPI driver for S5P6440 and S5P6450
mmc: sdhci-of: fix build on non-powerpc platforms
spi/imx: Add i.MX53 support
spi/dw_spi: don't treat NULL clk as an error
spi: tegra: don't treat NULL clk as an error
* 'i2c-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
i2c: Encourage move to dev_pm_ops by warning on use of legacy methods
i2c: Factor out runtime suspend checks from PM operations
i2c: Unregister dummy devices last on adapter removal
The compilation of drivers/acpi/pci_root.c fails if
CONFIG_PCIEPORTBUS is unset. Fix the problem.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>