Jaswinder Singh Rajput wrote:
> By executing Documentation/timers/hpet_example.c
>
> for polling, I requested for 3 iterations but it seems iteration work
> for only 2 as first expired time is always very small.
>
> # ./hpet_example poll /dev/hpet 10 3
> -hpet: executing poll
> hpet_poll: info.hi_flags 0x0
> hpet_poll: expired time = 0x13
> hpet_poll: revents = 0x1
> hpet_poll: data 0x1
> hpet_poll: expired time = 0x1868c
> hpet_poll: revents = 0x1
> hpet_poll: data 0x1
> hpet_poll: expired time = 0x18645
> hpet_poll: revents = 0x1
> hpet_poll: data 0x1
Clearing the HPET interrupt enable bit disables interrupt generation
but does not disable the timer, so the interrupt status bit will still
be set when the timer elapses. If another interrupt arrives before
the timer has been correctly programmed (due to some other device on
the same interrupt line, or CONFIG_DEBUG_SHIRQ), this results in an
extra unwanted interrupt event because the status bit is likely to be
set from comparator matches that happened before the device was opened.
Therefore, we have to ensure that the interrupt status bit is and
stays cleared until we actually program the timer.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Reported-by: Jaswinder Singh Rajput <jaswinderlinux@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Bob Picco <bpicco@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When the initialization code in hpet finds a memory resource and does not
find an IRQ, it does not unmap the memory resource previously mapped.
There are buggy BIOSes which report resources exactly like this and what
is worse the memory region bases point to normal RAM. This normally would
not matter since the space is not touched. But when PAT is turned on,
ioremap causes the page to be uncached and sets this bit in page->flags.
Then when the page is about to be used by the allocator, it is reported
as:
BUG: Bad page state in process md5sum pfn:3ed00
page:ffffea0000dbd800 count:0 mapcount:0 mapping:(null) index:0x0
page flags: 0x20000001000000(uncached)
Pid: 7956, comm: md5sum Not tainted 2.6.34-12-desktop #1
Call Trace:
[<ffffffff810df851>] bad_page+0xb1/0x100
[<ffffffff810dfa45>] prep_new_page+0x1a5/0x1c0
[<ffffffff810dfe01>] get_page_from_freelist+0x3a1/0x640
[<ffffffff810e01af>] __alloc_pages_nodemask+0x10f/0x6b0
...
In this particular case:
1) HPET returns 3ed00000 as memory region base, but it is not in
reserved ranges reported by the BIOS (excerpt):
BIOS-e820: 0000000000100000 - 00000000af6cf000 (usable)
BIOS-e820: 00000000af6cf000 - 00000000afdcf000 (reserved)
2) there is no IRQ resource reported by HPET method. On the other
hand, the Intel HPET specs (1.0a) says (3.2.5.1):
_CRS (
// Report 1K of memory consumed by this Timer Block
memory range consumed
// Optional: only used if BIOS allocates Interrupts [1]
IRQs consumed
)
[1] For case where Timer Block is configured to consume IRQ0/IRQ8 AND
Legacy 8254/Legacy RTC hardware still exists, the device objects
associated with 8254 & RTC devices should not report IRQ0/IRQ8 as
"consumed resources".
So in theory we should check whether if it is the case and use those
interrupts instead.
Anyway the address reported by the BIOS here is bogus, so non-presence
of IRQ doesn't mean the "optional" part in point 2).
Since I got no reply previously, fix this by simply unmapping the space
when IRQ is not found and memory region was mapped previously. It would
be probably more safe to walk the resources again and unmap appropriately
depending on type. But as we now use only ioremap for both 2 memory
resource types, it is not necessarily needed right now.
Addresses https://bugzilla.novell.com/show_bug.cgi?id=629908
Reported-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Clemens Ladisch <clemens@ladisch.de>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now, rw_verify_area() checsk f_pos is negative or not. And if negative,
returns -EINVAL.
But, some special files as /dev/(k)mem and /proc/<pid>/mem etc.. has
negative offsets. And we can't do any access via read/write to the
file(device).
So introduce FMODE_UNSIGNED_OFFSET to allow negative file offsets.
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
If the iucv_register() functions fails, the error recovery calls
iucv_unregister() which might cause the following stack backtrace:
(<0000000000100ab2> show_trace+0xee/0x144)
<00000000004f1842> panic+0xb6/0x248
<00000000001010a6> die+0x15a/0x16c
<000000000011d936> do_no_context+0xa6/0xe4
<00000000004f84dc> do_protection_exception+0x2e8/0x3a4
<0000000000113afc> pgm_exit+0x0/0x14
<00000000004e786e> iucv_unregister+0x5a/0x17c
(<00000000004e785e> iucv_unregister+0x4a/0x17c)
<000000000076de74> hvc_iucv_init+0x228/0x5dc
<00000000001000c2> do_one_initcall+0x3e/0x19c
<00000000007524a2> kernel_init+0x28e/0x404
<0000000000105dd6> kernel_thread_starter+0x6/0xc
<0000000000105dd0> kernel_thread_starter+0x0/0xc
Remove the call to iucv_unregister() and remove the goto label
as unregistering is the last step in the hvc_iucv initialization.
If iucv_register() fails, simply clean up hvc terminals and free
resources.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Don't spam dom0/xenconsoled with events unless we've actually added
something to the ring.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
A notifier chain is called whenever the vt code modifies a terminal
content, except for one case which is when the modification comes
through writes to /dev/vcs* devices. Let's add the missing notifier
invocation at the end of vcs_write() for that case too.
Signed-off-by: Nicolas Pitre <nicolas.pitre@canonical.com>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The /dev/vcs* devices are used, amongst other things, by accessibility
applications such as BRLTTY to display the screen content onto refreshable
braille displays. Currently this is performed by constantly reading from
/dev/vcsa0 whether or not the screen content has changed. Given the
default braille refresh rate of 25 times per second, this easily qualifies
as the biggest source of wake-up events preventing laptops from entering
deeper power saving states.
To avoid this periodic polling, let's add support for select()/poll() and
SIGIO with the /dev/vcs* devices. The implemented semantic is to report
data availability whenever the corresponding vt has seen some update after
the last read() operation. The application still has to lseek() back
as usual in order to read() the new data.
Not to create unwanted overhead, the needed data structure is allocated
and the vt notification callback is registered only when the poll or
fasync method is invoked for the first time per file instance.
Signed-off-by: Nicolas Pitre <nicolas.pitre@canonical.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Again basically cut and paste
Convert the main driver set to use the hooks for GICOUNT
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Dan Rosenberg noted that various drivers return the struct with uncleared
fields. Instead of spending forever trying to stomp all the drivers that
get it wrong (and every new driver) do the job in one place.
This first patch adds the needed operations and hooks them up, including
the needed USB midlayer and serial core plumbing.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Function tty_register_device may return ERR_PTR(...). Check for it.
Signed-off-by: Vasiliy Kulikov <segooon@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Vasiliy found that pci_disable_device is not called on fail paths in
mxser_probe. Actually, it is called from nowhere in the driver.
There are three changes needed:
1) don't use pseudo-generic mxser_release_res. Let's use it only from
ISA paths from now on. All the pci stuff is moved to probe and
remove PCI-related functions.
2) reorder fail-paths in the probe function so that it makes sense and
we can call them from the sequential code naturally (the further we
are the earlier label we go to).
3) add pci_disable_device both to mxser_probe and mxser_remove.
There is a nit of adding CONFIG_PCI ifdef to mxser_remove. it is
because this driver supports ISA-only compilations and it would choke
up on the newly added calls now.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Kulikov Vasiliy <segooon@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Ttyprintk is a pseudo TTY driver, which allows users to make printk
messages, via output to ttyprintk device. It is possible to store
"console" messages inline with kernel messages for better analyses of
the boot process, for example.
Signed-off-by: Samo Pogacnik <samo_pogacnik@t-2.net>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch removes __GFP_NOFAIL use from tty_add_file() and adds proper error
handling to the call-sites of the function.
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Some device drivers (mostly tty line disciplines) would like to have way
know a struct device instance corresponding to passed tty_struct. Add
a struct device pointer to struct tty_struct and populate it during
initialize_tty_struct().
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
In cleaning up the mask functions in bdd3072, the setting of the PTE
valid bit was dropped for Sandybridge.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
alloc_pci_dev allocates some memory, so that memory should be freed before
leaving the function in an error case.
A simplified version of the semantic match that finds this problem is:
(http://coccinelle.lip6.fr/)
// <smpl>
@r exists@
local idexpression x;
expression E;
identifier f1;
iterator I;
@@
x = alloc_pci_dev(...);
<... when != x
when != true (x == NULL || ...)
when != if (...) { <+...x...+> }
when != I (...) { <+...x...+> }
(
x == NULL
|
x == E
|
x->f1
)
...>
* return ...;
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Dan Carpenter <error27@gmail.com>
Dave Airlie <airlied@linux.ie>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Kyle McMartin <kyle@redhat.com>
Structure new_line is copied to userland with some padding fields unitialized.
It leads to leaking of stack memory.
Signed-off-by: Vasiliy Kulikov <segooon@gmail.com>
CC: stable@kernel.org
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
The ports are char devices; do not have seeking capabilities. Calling
nonseekable_open() from the fops_open() call and setting the llseek fops
pointer to no_llseek ensures an lseek() call from userspace returns
-ESPIPE.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
CC: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
If a port has registered for SIGIO signals, let the application
know that the port is getting unplugged.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Send a SIGIO signal when new data arrives on a port. This is sent only
when the process has requested for the signal to be sent using fcntl().
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
A process can request for SIGIO on host connect / disconnect events
using the O_ASYNC file flag using fcntl().
If that's requested, and if the guest-side connection for the port is
open, any host-side open/close events for that port will raise a SIGIO.
The process can then use poll() within the signal handler to find out
which port triggered the signal.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Explain in a comment why there's no need to reference-count the portdev
struct: when a device is yanked out, we can't do anything more with it
anyway so just give up doing anything more with the data or the vqs and
exit cleanly.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
When a port got hot-unplugged, when a port was open, any file operation
after the unplugging resulted in a crash. This is fixed by ref-counting
the port structure, and releasing it only when the file is closed.
This splits the unplug operation in two parts: first marks the port
as unavailable, removes all the buffers in the vqs and removes the port
from the per-device list of ports. The second stage, invoked when all
references drop to zero, releases the chardev and frees all other memory.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This moves to using cdev on the heap instead of it being embedded in the
ports struct. This helps individual refcounting and will allow us to
properly remove cdev structs after hot-unplugs and close operations.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
To convert to using cdev as a pointer to avoid kref troubles, we have to
use a different method to get to a port from an inode than the current
container_of method.
Add find_port_by_devt() that looks up all portdevs and ports with those
portdevs to find the right port.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The virtio_console.c driver is capable of handling multiple devices at a
time. Maintain a list of devices for future traversal.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
When a port is removed, we have to assume the port is gone. So a
success/failure return value doesn't make sense.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
When a port is hot-unplugged while an app was blocked on a write() call,
the call was unblocked but would not get an error returned.
Return -ENODEV to ensure the app knows the port has gone away.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
When a port is hot-unplugged while an app was blocked on a read() call,
the call was unblocked but would not get an error returned.
Return -ENODEV to ensure the app knows the port has gone away.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
When a port is hot-unplugged while an app is blocked on poll(), unblock
the poll() and return.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
If a chardev is closed, any blocked read / poll calls should just return
and not attempt to use other state.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
A portdev may have been hot-unplugged while a port was open()ed. Skip
sending control messages when the portdev isn't valid.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
If a portdev isn't using multiport support, it won't have any control vq
data to remove.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The virtqueues should be disabled before attempting to remove the
device.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Fix the following warning:
drivers/char/tpm/tpm.c:1085: warning: `tpm_suspend_setup' defined but not used
and make the workaround operable in case when TPM is compiled as a module.
As a side-effect the option will be called tpm.suspend_pcr.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Cc: Rajiv Andrade <srajiv@linux.vnet.ibm.com>
Cc: David Safford <safford@watson.ibm.com>
Cc: James Morris <jmorris@namei.org>
Cc: Debora Velarde <debora@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: James Morris <jmorris@namei.org>
If the host is slow in reading data or doesn't read data at all,
blocking write calls not only blocked the program that called write()
but the entire guest itself.
To overcome this, let's not block till the host signals it has given
back the virtio ring element we passed it. Instead, send the buffer to
the host and return to userspace. This operation then becomes similar
to how non-blocking writes work, so let's use the existing code for this
path as well.
This code change also ensures blocking write calls do get blocked if
there's not enough room in the virtio ring as well as they don't return
-EAGAIN to userspace.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Acked-by: Hans de Goede <hdegoede@redhat.com>
CC: stable@kernel.org
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This driver already has a global mutex, so let's just
use that in the open function instead of the BKL.
It may not even be needed there, but this patch should
have the smallest impact.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Mark Gross <mark.gross@intel.com>
RAW_SETBIND and RAW_GETBIND 32bit versions are fscked in interesting ways.
1) fs/compat_ioctl.c has COMPATIBLE_IOCTL(RAW_SETBIND) followed by
HANDLE_IOCTL(RAW_SETBIND, raw_ioctl). The latter is ignored.
2) on amd64 (and itanic) the damn thing is broken - we have int + u64 + u64
and layouts on i386 and amd64 are _not_ the same. raw_ioctl() would
work there, but it's never called due to (1). As it is, i386 /sbin/raw
definitely doesn't work on amd64 boxen.
3) switching to raw_ioctl() as is would *not* work on e.g. sparc64 and ppc64,
which would be rather sad, seeing that normal userland there is 32bit.
The thing is, slapping __packed on the struct in question does not DTRT -
it eliminates *all* padding. The real solution is to use compat_u64.
4) of course, all that stuff has no business being outside of raw.c in the
first place - there should be ->compat_ioctl() for /dev/rawctl instead of
messing with compat_ioctl.c.
[akpm@linux-foundation.org: coding-style fixes]
[arnd@arndb.de: port to 2.6.36]
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This was a missing piece from 41a5142 that dropped recognition of the
AGP module for the second B43 variant.
Reported-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: stable@kernel.org
TTM-based DRM drivers need to be able to bind user memory to the AGP
aperture. This patch fixes the "[TTM] AGP Bind memory failed." errors
and the subsequent fallout seen with the nouveau driver.
Signed-off-by: Francisco Jerez <currojerez@riseup.net>
Tested-by: Grzesiek Sójka <pld@pfu.pl>
Signed-off-by: Dave Airlie <airlied@redhat.com>
The patch below updates broken web addresses in the kernel
Signed-off-by: Justin P. Mattock <justinmattock@gmail.com>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Finn Thain <fthain@telegraphics.com.au>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Dimitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Mike Frysinger <vapier.adi@gmail.com>
Acked-by: Ben Pfaff <blp@cs.stanford.edu>
Acked-by: Hans J. Koch <hjk@linutronix.de>
Reviewed-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
All file_operations should get a .llseek operation so we can make
nonseekable_open the default for future file operations without a
.llseek pointer.
The three cases that we can automatically detect are no_llseek, seq_lseek
and default_llseek. For cases where we can we can automatically prove that
the file offset is always ignored, we use noop_llseek, which maintains
the current behavior of not returning an error from a seek.
New drivers should normally not use noop_llseek but instead use no_llseek
and call nonseekable_open at open time. Existing drivers can be converted
to do the same when the maintainer knows for certain that no user code
relies on calling seek on the device file.
The generated code is often incorrectly indented and right now contains
comments that clarify for each added line why a specific variant was
chosen. In the version that gets submitted upstream, the comments will
be gone and I will manually fix the indentation, because there does not
seem to be a way to do that using coccinelle.
Some amount of new code is currently sitting in linux-next that should get
the same modifications, which I will do at the end of the merge window.
Many thanks to Julia Lawall for helping me learn to write a semantic
patch that does all this.
===== begin semantic patch =====
// This adds an llseek= method to all file operations,
// as a preparation for making no_llseek the default.
//
// The rules are
// - use no_llseek explicitly if we do nonseekable_open
// - use seq_lseek for sequential files
// - use default_llseek if we know we access f_pos
// - use noop_llseek if we know we don't access f_pos,
// but we still want to allow users to call lseek
//
@ open1 exists @
identifier nested_open;
@@
nested_open(...)
{
<+...
nonseekable_open(...)
...+>
}
@ open exists@
identifier open_f;
identifier i, f;
identifier open1.nested_open;
@@
int open_f(struct inode *i, struct file *f)
{
<+...
(
nonseekable_open(...)
|
nested_open(...)
)
...+>
}
@ read disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}
@ read_no_fpos disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
... when != off
}
@ write @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}
@ write_no_fpos @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
... when != off
}
@ fops0 @
identifier fops;
@@
struct file_operations fops = {
...
};
@ has_llseek depends on fops0 @
identifier fops0.fops;
identifier llseek_f;
@@
struct file_operations fops = {
...
.llseek = llseek_f,
...
};
@ has_read depends on fops0 @
identifier fops0.fops;
identifier read_f;
@@
struct file_operations fops = {
...
.read = read_f,
...
};
@ has_write depends on fops0 @
identifier fops0.fops;
identifier write_f;
@@
struct file_operations fops = {
...
.write = write_f,
...
};
@ has_open depends on fops0 @
identifier fops0.fops;
identifier open_f;
@@
struct file_operations fops = {
...
.open = open_f,
...
};
// use no_llseek if we call nonseekable_open
////////////////////////////////////////////
@ nonseekable1 depends on !has_llseek && has_open @
identifier fops0.fops;
identifier nso ~= "nonseekable_open";
@@
struct file_operations fops = {
... .open = nso, ...
+.llseek = no_llseek, /* nonseekable */
};
@ nonseekable2 depends on !has_llseek @
identifier fops0.fops;
identifier open.open_f;
@@
struct file_operations fops = {
... .open = open_f, ...
+.llseek = no_llseek, /* open uses nonseekable */
};
// use seq_lseek for sequential files
/////////////////////////////////////
@ seq depends on !has_llseek @
identifier fops0.fops;
identifier sr ~= "seq_read";
@@
struct file_operations fops = {
... .read = sr, ...
+.llseek = seq_lseek, /* we have seq_read */
};
// use default_llseek if there is a readdir
///////////////////////////////////////////
@ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier readdir_e;
@@
// any other fop is used that changes pos
struct file_operations fops = {
... .readdir = readdir_e, ...
+.llseek = default_llseek, /* readdir is present */
};
// use default_llseek if at least one of read/write touches f_pos
/////////////////////////////////////////////////////////////////
@ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read.read_f;
@@
// read fops use offset
struct file_operations fops = {
... .read = read_f, ...
+.llseek = default_llseek, /* read accesses f_pos */
};
@ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write.write_f;
@@
// write fops use offset
struct file_operations fops = {
... .write = write_f, ...
+ .llseek = default_llseek, /* write accesses f_pos */
};
// Use noop_llseek if neither read nor write accesses f_pos
///////////////////////////////////////////////////////////
@ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
identifier write_no_fpos.write_f;
@@
// write fops use offset
struct file_operations fops = {
...
.write = write_f,
.read = read_f,
...
+.llseek = noop_llseek, /* read and write both use no f_pos */
};
@ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write_no_fpos.write_f;
@@
struct file_operations fops = {
... .write = write_f, ...
+.llseek = noop_llseek, /* write uses no f_pos */
};
@ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
@@
struct file_operations fops = {
... .read = read_f, ...
+.llseek = noop_llseek, /* read uses no f_pos */
};
@ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
@@
struct file_operations fops = {
...
+.llseek = noop_llseek, /* no read or write fn */
};
===== End semantic patch =====
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Julia Lawall <julia@diku.dk>
Cc: Christoph Hellwig <hch@infradead.org>
hvc_alloc() may fail, if so exit from init() with error.
Signed-off-by: Vasiliy Kulikov <segooon@gmail.com>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
All these files use the big kernel lock in a trivial
way to serialize their private file operations,
typically resulting from an earlier semi-automatic
pushdown from VFS.
None of these drivers appears to want to lock against
other code, and they all use the BKL as the top-level
lock in their file operations, meaning that there
is no lock-order inversion problem.
Consequently, we can remove the BKL completely,
replacing it with a per-file mutex in every case.
Using a scripted approach means we can avoid
typos.
These drivers do not seem to be under active
maintainance from my brief investigation. Apologies
to those maintainers that I have missed.
file=$1
name=$2
if grep -q lock_kernel ${file} ; then
if grep -q 'include.*linux.mutex.h' ${file} ; then
sed -i '/include.*<linux\/smp_lock.h>/d' ${file}
else
sed -i 's/include.*<linux\/smp_lock.h>.*$/include <linux\/mutex.h>/g' ${file}
fi
sed -i ${file} \
-e "/^#include.*linux.mutex.h/,$ {
1,/^\(static\|int\|long\)/ {
/^\(static\|int\|long\)/istatic DEFINE_MUTEX(${name}_mutex);
} }" \
-e "s/\(un\)*lock_kernel\>[ ]*()/mutex_\1lock(\&${name}_mutex)/g" \
-e '/[ ]*cycle_kernel_lock();/d'
else
sed -i -e '/include.*\<smp_lock.h\>/d' ${file} \
-e '/cycle_kernel_lock()/d'
fi
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Similarly to the keyboard handler, we are called by different input
devices and thus need to add spinlock if we want to maintain our
state properly.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
printk() statements on module load or unload are frowned upon. Also,
add a few __init or __exit declarations.
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Clemens Ladisch