Got the following oops just before reboot:
Unable to handle kernel NULL pointer dereference at virtual address 00000000
[<8028d300>] (__list_del_entry+0x44/0xac)
[<802e3320>] (__fw_load_abort.part.13+0x1c/0x50)
[<802e337c>] (fw_shutdown_notify+0x28/0x50)
[<80034f80>] (notifier_call_chain.isra.1+0x5c/0x9c)
[<800350ec>] (__blocking_notifier_call_chain+0x44/0x58)
[<80035114>] (blocking_notifier_call_chain+0x14/0x18)
[<80035d64>] (kernel_restart_prepare+0x14/0x38)
[<80035d94>] (kernel_restart+0xc/0x50)
The following race condition triggers here:
_request_firmware_load()
device_create_file(...)
kobject_uevent(...)
(schedule)
(resume)
firmware_loading_store(1)
firmware_loading_store(0)
list_del_init(&buf->pending_list)
(schedule)
(resume)
list_add(&buf->pending_list, &pending_fw_head);
wait_for_completion(&buf->completion);
causing an oops later when walking pending_list after the firmware has
been released.
The proposed fix is to move the list_add() before sysfs attribute
creation.
Signed-off-by: Maxime Bizon <mbizon@freebox.fr>
Acked-by: Ming Lei <ming.lei@canonical.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use __ATTR_RW() instead of __ATTR() to make it more obvious what the
type of attribute is being created.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch fixes another compiling warning with PM_SLEEP unset:
drivers/base/firmware_class.c:221:29: warning: 'fw_lookup_buf' defined
but not used [-Wunused-function]
This time I do build kernel with both PM_SLEEP set and unset, and no
warning found any more with the patch.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch fixes the below compile warning:
drivers/base/firmware_class.c:1254:12: warning: 'cache_firmware' defined
but not used [-Wunused-function]
static int cache_firmware(const char *fw_name)
^
drivers/base/firmware_class.c:1281:12: warning: 'uncache_firmware'
defined but not used [-Wunused-function]
static int uncache_firmware(const char *fw_name)
^
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This resolves the merge issues with drivers/base/firmware_class.c
Thanks to Ming Lei for the patch and hints on how to resolve it.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fw_priv->buf is accessed in both request_firmware_load() and
writing to sysfs file of 'loading' context, but not protected
by 'fw_lock' entirely. The patch makes sure that access on
'fw_priv->buf' is protected by the lock.
So fixes the double abort problem reported by nirinA raseliarison:
http://lkml.org/lkml/2013/6/14/188
Reported-and-tested-by: nirinA raseliarison <nirina.raseliarison@gmail.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: stable <stable@vger.kernel.org> # 3.9
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
module reference doesn't cover direct loading path, so this patch
simply holds the module in the whole life time of request_firmware()
to fix the problem.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Looks no driver has the explict requirement for the two exported
API, just don't export them anymore.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The commit ddf1f0648e8c("firmware loader: fix build failure
with !CONFIG_FW_LOADER_USER_HELPER") introduces the below
warning:
drivers/base/firmware_class.c:921:13: warning:
'kill_requests_without_uevent' defined but not used [-Wunused-function]
So fix it by defining kill_requests_without_uevent() only if
CONFIG_PM_SLEEP is set.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch fixes one build failure which is introduced by the patch
below:
driver core: firmware loader: kill FW_ACTION_NOHOTPLUG requests
before suspend
When CONFIG_FW_LOADER_USER_HELPER is unset, kill_requests_without_uevent()
should be nop because no userspace loading is involved.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch kills the firmware loading requests of FW_ACTION_NOHOTPLUG
before suspend to avoid blocking suspend because there is no timeout
for these requests.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Generally there are only two drivers which don't need uevent to
handle firmware loading, so don't cache these firmwares during
suspend for these drivers since doing that may block firmware
loading forever.
Both the two drivers are involved in private firmware images, so
they don't hit in direct loading too.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Move EXPORT_SYMBOL annotations so they follow immediately after the
closing function brace line.
Signed-off-by: Daniel Mack <zonque@gmail.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When a system goes to reboot/shutdown, it tries to disable the
usermode helper via usermodehelper_disable(). This might be blocked
when a driver tries to load a firmware beforehand and it's stuck by
some reason. For example, dell_rbu driver loads the firmware in
non-hotplug mode and waits for user-space clearing the loading sysfs
flag. If user-space doesn't clear the flag, it waits forever, thus
blocks the reboot, too.
As a workaround, in this patch, the firmware class driver registers a
reboot notifier so that it can abort all pending f/w bufs before
issuing usermodehelper_disable().
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull vfs pile (part one) from Al Viro:
"Assorted stuff - cleaning namei.c up a bit, fixing ->d_name/->d_parent
locking violations, etc.
The most visible changes here are death of FS_REVAL_DOT (replaced with
"has ->d_weak_revalidate()") and a new helper getting from struct file
to inode. Some bits of preparation to xattr method interface changes.
Misc patches by various people sent this cycle *and* ocfs2 fixes from
several cycles ago that should've been upstream right then.
PS: the next vfs pile will be xattr stuff."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits)
saner proc_get_inode() calling conventions
proc: avoid extra pde_put() in proc_fill_super()
fs: change return values from -EACCES to -EPERM
fs/exec.c: make bprm_mm_init() static
ocfs2/dlm: use GFP_ATOMIC inside a spin_lock
ocfs2: fix possible use-after-free with AIO
ocfs2: Fix oops in ocfs2_fast_symlink_readpage() code path
get_empty_filp()/alloc_file() leave both ->f_pos and ->f_version zero
target: writev() on single-element vector is pointless
export kernel_write(), convert open-coded instances
fs: encode_fh: return FILEID_INVALID if invalid fid_type
kill f_vfsmnt
vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op
nfsd: handle vfs_getattr errors in acl protocol
switch vfs_getattr() to struct path
default SET_PERSONALITY() in linux/elf.h
ceph: prepopulate inodes only when request is aborted
d_hash_and_lookup(): export, switch open-coded instances
9p: switch v9fs_set_create_acl() to inode+fid, do it before d_instantiate()
9p: split dropping the acls from v9fs_set_create_acl()
...
FW_STATUS_ABORT can be set only during the user-helper invocation,
thus we can ignore the check when CONFIG_HW_LOADER_USER_HELPER is
disabled.
Acked-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
By shuffling the code, reduce a few ifdefs in firmware_class.c.
Also, firmware_buf fmt field is changed to is_pages_buf boolean for
simplification.
Acked-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch adds a new kconfig, CONFIG_FW_LOADER_USER_HELPER, and
guards the user-helper codes in firmware_class.c with ifdefs.
Yeah, yeah, there are lots of ifdefs in this patch. The further
clean-up with code shuffling follows in the next.
Acked-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since 3.7 kernel, the firmware loader can read the firmware files
directly, and the traditional user-mode helper is invoked only as a
fallback. This seems working pretty well, and the next step would be
to reduce the redundant user-mode helper stuff in future.
This patch is a preparation for that: refactor the code for splitting
user-mode helper stuff more easily. No functional change.
Acked-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If the requested firmware file size is 0 bytes in the filesytem, we
will try to vmalloc(0), which causes a warning:
vmalloc: allocation failure: 0 bytes
kworker/1:1: page allocation failure: order:0, mode:0xd2
__vmalloc_node_range+0x164/0x208
__vmalloc_node+0x4c/0x58
vmalloc+0x38/0x44
_request_firmware_load+0x220/0x6b0
request_firmware+0x64/0xc8
wl18xx_setup+0xb4/0x570 [wl18xx]
wlcore_nvs_cb+0x64/0x9f8 [wlcore]
request_firmware_work_func+0x94/0x100
process_one_work+0x1d0/0x750
worker_thread+0x184/0x4ac
kthread+0xb4/0xc0
To fix this, check whether the file size is less than or equal to zero
in fw_read_file_contents().
Cc: stable <stable@vger.kernel.org> [3.7]
Signed-off-by: Luciano Coelho <coelho@ti.com>
Acked-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch documents the firmware cache mechanism so that
users of request_firmware() know that it can be called
safely inside device's suspend and resume callback, and
the device's firmware needn't be cached any more by individual
driver itself to deal with firmware loss during system resume.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch introduces one module parameter of 'path' in firmware_class
to support customizing firmware image search path, so that people can
use its own firmware path if the default built-in paths can't meet their
demand[1], and the typical usage is passing the below from kernel command
parameter when 'firmware_class' is built in kernel:
firmware_class.path=$CUSTOMIZED_PATH
[1], https://lkml.org/lkml/2012/10/11/337
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The comment above fw_file_size() suggests it is noinline for stack size
reasons. Use noinline_for_stack to make this more clear.
Signed-off-by: Cesar Eduardo Barros <cesarb@cesarb.net>
Acked-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is one race that both request_firmware() with the same
firmware name.
The race scenerio is as below:
CPU1 CPU2
request_firmware() -->
_request_firmware_load() return err another request_firmware() is coming -->
_request_firmware_cleanup is called --> _request_firmware_prepare -->
release_firmware ---> fw_lookup_and_allocate_buf -->
spin_lock(&fwc->lock)
... __fw_lookup_buf() return true
fw_free_buf() will be called --> ...
kref_put -->
decrease the refcount to 0
kref_get(&tmp->ref) ==> it will trigger warning
due to refcount == 0
__fw_free_buf() -->
... spin_unlock(&fwc->lock)
spin_lock(&fwc->lock)
list_del(&buf->list)
spin_unlock(&fwc->lock)
kfree(buf)
After that, the freed buf will be used.
The key race is decreasing refcount to 0 and list_del is not protected together by
fwc->lock, and it is possible another thread try to get it between refcount==0
and list_del.
Fix it here to protect it together.
Acked-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: liu chuansheng <chuansheng.liu@intel.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is a race as below when calling request_firmware():
CPU1 CPU2
write 0 > loading
mutex_lock(&fw_lock)
...
set_bit FW_STATUS_DONE class_timeout is coming
set_bit FW_STATUS_ABORT
complete_all &completion
...
mutex_unlock(&fw_lock)
In this time, the bit FW_STATUS_DONE and FW_STATUS_ABORT are set,
and request_firmware() will return failure due to condition in
_request_firmware_load():
if (!buf->size || test_bit(FW_STATUS_ABORT, &buf->status))
retval = -ENOENT;
But from the above scenerio, it should be a successful requesting.
So we need judge if the bit FW_STATUS_DONE is already set before
calling fw_load_abort() in timeout function.
As Ming's proposal, we need change the timer into sched_work to
benefit from using &fw_lock mutex also.
Signed-off-by: liu chuansheng <chuansheng.liu@intel.com>
Acked-by: Ming Lei <ming.lei@canonical.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
async.c has provided synchronization mechanism on async_schedule_*,
so use async_synchronize_full_domain to sync caching firmware instead
of reinventing the wheel.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Firstly 'firmware_buf' is introduced to make all loading requests
to share one firmware kernel buffer, so firmware_buf should
be used in direct loading for saving memory and speedup firmware
loading.
Secondly, the commit below
abb139e75c2cdbb955e840d6331cb5863e409d0e(firmware:teach
the kernel to load firmware files directly from the filesystem)
introduces direct loading for fixing udev regression, but it
bypasses the firmware cache meachnism, so this patch enables
caching firmware for direct loading case since it is still needed
to solve drivers' dependency during system resume.
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Several loading requests may be pending on one same
firmware buf, and this patch moves fw_map_pages_buf()
before complete_all(&fw_buf->completion) and let all
requests see the mapped 'buf->data' once the loading
is completed.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Under 'Opportunistic sleep' situation, system sleep might be
triggered very frequently, so the uncahce work may not be completed
before caching firmware during next suspend.
This patch cancels the uncache work before caching firmware to
fix the problem above.
Also this patch optimizes the cacheing firmware mechanism a bit by
only storing one firmware cache entry for one firmware image.
So if the firmware is still cached during suspend, it doesn't need
to be loaded from user space any more.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fengguang correctly points out that the firmware reading should not use
vfs_read(), since the buffer is in kernel space.
The vfs_read() just happened to work for kernel threads, but sparse
warns about the incorrect address spaces, and it's definitely incorrect
and could fail for other users of the firmware loading.
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is a first step in allowing people to by-pass udev for loading
device firmware. Current versions of udev will deadlock (causing us to
block for the 30 second timeout) under some circumstances if the
firmware is loaded as part of the module initialization path, and this
is causing problems for media drivers in particular.
The current patch hardcodes the firmware path that udev uses by default,
and will fall back to the legacy udev mode if the firmware cannot be
found there. We'd like to add support for both configuring the paths
and the fallback behaviour, but in the meantime this hopefully fixes the
immediate problem, while also giving us a way forward.
[ v2: Some VFS layer interface cleanups suggested by Al Viro ]
[ v3: use the default udev paths suggested by Kay Sievers ]
Suggested-by: Ivan Kalvachev <ikalvachev@gmail.com>
Acked-by: Greg KH <gregkh@linuxfoundation.org>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Mauro Carvalho Chehab <mchehab@redhat.com>
Cc: Kay Sievers <kay@redhat.com>
Cc: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch replaces the previous macro of CONFIG_PM with
CONFIG_PM_SLEEP becasue firmware cache is only used in
system sleep situations.
Also this patch fixes the below compile warning when
CONFIG_PM=n:
drivers/base/firmware_class.c:1147: warning: 'device_cache_fw_images'
defined but not used
drivers/base/firmware_class.c:1212: warning:
'device_uncache_fw_images_delay' defined but not used
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
After starting caching firmware, there is still some time left
before devices are suspended, during the period, request_firmware
or its nowait version may still be triggered by the below situations
to load firmware images which can't be cached during suspend/resume
cycle.
- new devices added
- driver bind
- or device open kind of things
This patch utilizes the piggyback trick to cache firmware for
this kind of situation: just increase the firmware buf's reference
count and add the fw name entry into cache entry list after starting
caching firmware and before syscore_suspend() is called.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If the requested firmware image doesn't exist, firmware->priv
should be set for the later concurrent requests, otherwise
warning and oops will be triggered inside firmware_free_data().
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
device_cache_fw_images need to iterate devices in system,
so this patch applies the introduced dpm_for_each_dev to
avoid link failure if CONFIG_FW_LOADER is m.
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
'return 0' should be added to fw_pm_notify if !PM because
return value of the funcion is defined as 'int'.
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch implements caching devices' firmware automatically
during system syspend/resume cycle, so any device drivers can
call request_firmware or request_firmware_nowait inside resume
path to get the cached firmware if they have loaded firmwares
successfully at least once before entering suspend.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Because device_cache_fw_images only cache the firmware which has been
loaded sucessfully at leat once, using a small loading timeout should
be reasonable.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch introduces the three helpers below:
void device_cache_fw_images(void)
void device_uncache_fw_images(void)
void device_uncache_fw_images_delay(unsigned long)
so we can use device_cache_fw_images() to cache firmware for
all devices which need firmware to work, and the device driver
can get the firmware easily from kernel memory when system isn't
ready for completing requests of loading firmware.
After system is ready for completing firmware loading, driver core
will call device_uncache_fw_images() or its delay version to free
the cached firmware.
The above helpers will be used to cache device firmware during
system suspend/resume cycle in the following patches.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch will store firmware name into devres list of the device
which is requesting firmware loading, so that we can implement
auto cache and uncache firmware for devices in need.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
request_firmware_nowait is allowed to be called in atomic
context now if @gfp is GFP_ATOMIC, so fix the obsolete
comments and states which situations are suitable for using
it.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Callers of request_firmware* must hold the reference count of
@device, otherwise it is easy to trigger oops since the firmware
loader device is the child of @device.
This patch adds comments about the usage. In fact, most of drivers
call request_firmware* in its probe() or open(), so the constraint
should be reasonable and can be satisfied.
Also this patch holds the reference count of @device before
schedule_work() in request_firmware_nowait() to avoid that
the @device is released after request_firmware_nowait returns
and before the worker function is scheduled.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patches introduce two kernel APIs of cache_firmware and
uncache_firmware, both of which take the firmware file name
as the only parameter.
So any drivers can call cache_firmware to cache the specified
firmware file into kernel memory, and can use the cached firmware
in situations which can't request firmware from user space.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch always let firmware_buf own the pages buffer allocated
inside firmware_data_write, and add all instances of firmware_buf
into the firmware cache global list. Also introduce one private field
in 'struct firmware', so release_firmware will see the instance of
firmware_buf associated with the current firmware instance, then just
'free' the instance of firmware_buf.
The firmware_buf instance represents one pages buffer for one
firmware image, so lots of firmware loading requests can share
the same firmware_buf instance if they request the same firmware
image file.
This patch will make implementation of the following cache_firmware/
uncache_firmware very easy and simple.
In fact, the patch improves request_formware/release_firmware:
- only request userspace to write firmware image once if
several devices share one same firmware image and its drivers
call request_firmware concurrently.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch introduces struct firmware_buf to describe the buffer
which holds the firmware data, which will make the following
cache_firmware/uncache_firmware implemented easily.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If one device driver calls request_firmware_nowait() to request
several different firmwares' loading, device_add() will return
failure since all firmware loader device use same name of the
device who is requesting firmware.
This patch always use the name of firmware image as the firmware
loader device name to fix the problem since the following patches
for caching firmware will make sure only one loading for same
firmware is alllowd at the same time.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The wmb() inside fw_load_abort is not necessary, since
complete() and wait_on_completion() has implied one pair
of memory barrier.
Also wmb() isn't a correct usage, so just remove it.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch fixes two races in loading firmware:
1, FW_STATUS_DONE should be set before waking up the task waitting
on _request_firmware_load, otherwise FW_STATUS_ABORT may be
thought as DONE mistakenly.
2, Inside _request_firmware_load(), there is a small window between
wait_for_completion() and mutex_lock(&fw_lock), and 'echo 1 > loading'
still may happen during the period, so this patch checks FW_STATUS_DONE
to prevent pages' buffer completed from being freed in firmware_loading_store.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch doesn't transfer ownership of pages' buffer to the
instance of firmware until the firmware loading is completed,
which will simplify firmware_loading_store a lot, so help
to introduce the following cache_firmware and uncache_firmware
mechanism during system suspend-resume cycle.
In fact, this patch fixes one bug: if writing data into
firmware loader device is bypassed between writting 1 and 0 to
'loading', OOPS will be triggered without the patch.
Also handle the vmap failure case, and add some comments to make
code more readable.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Maxime Bizon