linux/drivers/video/fbsysfs.c

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/*
* fbsysfs.c - framebuffer device class and attributes
*
* Copyright (c) 2004 James Simmons <jsimmons@infradead.org>
*
* This program is free software you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
/*
* Note: currently there's only stubs for framebuffer_alloc and
* framebuffer_release here. The reson for that is that until all drivers
* are converted to use it a sysfsification will open OOPSable races.
*/
#include <linux/kernel.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 08:04:11 +00:00
#include <linux/slab.h>
#include <linux/fb.h>
#include <linux/console.h>
#include <linux/module.h>
#define FB_SYSFS_FLAG_ATTR 1
/**
* framebuffer_alloc - creates a new frame buffer info structure
*
* @size: size of driver private data, can be zero
* @dev: pointer to the device for this fb, this can be NULL
*
* Creates a new frame buffer info structure. Also reserves @size bytes
* for driver private data (info->par). info->par (if any) will be
* aligned to sizeof(long).
*
* Returns the new structure, or NULL if an error occurred.
*
*/
struct fb_info *framebuffer_alloc(size_t size, struct device *dev)
{
#define BYTES_PER_LONG (BITS_PER_LONG/8)
#define PADDING (BYTES_PER_LONG - (sizeof(struct fb_info) % BYTES_PER_LONG))
int fb_info_size = sizeof(struct fb_info);
struct fb_info *info;
char *p;
if (size)
fb_info_size += PADDING;
p = kzalloc(fb_info_size + size, GFP_KERNEL);
if (!p)
return NULL;
info = (struct fb_info *) p;
if (size)
info->par = p + fb_info_size;
info->device = dev;
#ifdef CONFIG_FB_BACKLIGHT
mutex_init(&info->bl_curve_mutex);
#endif
return info;
#undef PADDING
#undef BYTES_PER_LONG
}
EXPORT_SYMBOL(framebuffer_alloc);
/**
* framebuffer_release - marks the structure available for freeing
*
* @info: frame buffer info structure
*
* Drop the reference count of the device embedded in the
* framebuffer info structure.
*
*/
void framebuffer_release(struct fb_info *info)
{
kfree(info->apertures);
kfree(info);
}
EXPORT_SYMBOL(framebuffer_release);
static int activate(struct fb_info *fb_info, struct fb_var_screeninfo *var)
{
int err;
var->activate |= FB_ACTIVATE_FORCE;
console_lock();
fb_info->flags |= FBINFO_MISC_USEREVENT;
err = fb_set_var(fb_info, var);
fb_info->flags &= ~FBINFO_MISC_USEREVENT;
console_unlock();
if (err)
return err;
return 0;
}
static int mode_string(char *buf, unsigned int offset,
const struct fb_videomode *mode)
{
char m = 'U';
char v = 'p';
if (mode->flag & FB_MODE_IS_DETAILED)
m = 'D';
if (mode->flag & FB_MODE_IS_VESA)
m = 'V';
if (mode->flag & FB_MODE_IS_STANDARD)
m = 'S';
if (mode->vmode & FB_VMODE_INTERLACED)
v = 'i';
if (mode->vmode & FB_VMODE_DOUBLE)
v = 'd';
return snprintf(&buf[offset], PAGE_SIZE - offset, "%c:%dx%d%c-%d\n",
m, mode->xres, mode->yres, v, mode->refresh);
}
static ssize_t store_mode(struct device *device, struct device_attribute *attr,
const char *buf, size_t count)
{
struct fb_info *fb_info = dev_get_drvdata(device);
char mstr[100];
struct fb_var_screeninfo var;
struct fb_modelist *modelist;
struct fb_videomode *mode;
struct list_head *pos;
size_t i;
int err;
memset(&var, 0, sizeof(var));
list_for_each(pos, &fb_info->modelist) {
modelist = list_entry(pos, struct fb_modelist, list);
mode = &modelist->mode;
i = mode_string(mstr, 0, mode);
if (strncmp(mstr, buf, max(count, i)) == 0) {
var = fb_info->var;
fb_videomode_to_var(&var, mode);
if ((err = activate(fb_info, &var)))
return err;
fb_info->mode = mode;
return count;
}
}
return -EINVAL;
}
static ssize_t show_mode(struct device *device, struct device_attribute *attr,
char *buf)
{
struct fb_info *fb_info = dev_get_drvdata(device);
if (!fb_info->mode)
return 0;
return mode_string(buf, 0, fb_info->mode);
}
static ssize_t store_modes(struct device *device,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct fb_info *fb_info = dev_get_drvdata(device);
LIST_HEAD(old_list);
int i = count / sizeof(struct fb_videomode);
if (i * sizeof(struct fb_videomode) != count)
return -EINVAL;
console_lock();
list_splice(&fb_info->modelist, &old_list);
fb_videomode_to_modelist((const struct fb_videomode *)buf, i,
&fb_info->modelist);
if (fb_new_modelist(fb_info)) {
fb_destroy_modelist(&fb_info->modelist);
list_splice(&old_list, &fb_info->modelist);
} else
fb_destroy_modelist(&old_list);
console_unlock();
return 0;
}
static ssize_t show_modes(struct device *device, struct device_attribute *attr,
char *buf)
{
struct fb_info *fb_info = dev_get_drvdata(device);
unsigned int i;
struct list_head *pos;
struct fb_modelist *modelist;
const struct fb_videomode *mode;
i = 0;
list_for_each(pos, &fb_info->modelist) {
modelist = list_entry(pos, struct fb_modelist, list);
mode = &modelist->mode;
i += mode_string(buf, i, mode);
}
return i;
}
static ssize_t store_bpp(struct device *device, struct device_attribute *attr,
const char *buf, size_t count)
{
struct fb_info *fb_info = dev_get_drvdata(device);
struct fb_var_screeninfo var;
char ** last = NULL;
int err;
var = fb_info->var;
var.bits_per_pixel = simple_strtoul(buf, last, 0);
if ((err = activate(fb_info, &var)))
return err;
return count;
}
static ssize_t show_bpp(struct device *device, struct device_attribute *attr,
char *buf)
{
struct fb_info *fb_info = dev_get_drvdata(device);
return snprintf(buf, PAGE_SIZE, "%d\n", fb_info->var.bits_per_pixel);
}
static ssize_t store_rotate(struct device *device,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct fb_info *fb_info = dev_get_drvdata(device);
struct fb_var_screeninfo var;
char **last = NULL;
int err;
var = fb_info->var;
var.rotate = simple_strtoul(buf, last, 0);
if ((err = activate(fb_info, &var)))
return err;
return count;
}
static ssize_t show_rotate(struct device *device,
struct device_attribute *attr, char *buf)
{
struct fb_info *fb_info = dev_get_drvdata(device);
return snprintf(buf, PAGE_SIZE, "%d\n", fb_info->var.rotate);
}
static ssize_t store_virtual(struct device *device,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct fb_info *fb_info = dev_get_drvdata(device);
struct fb_var_screeninfo var;
char *last = NULL;
int err;
var = fb_info->var;
var.xres_virtual = simple_strtoul(buf, &last, 0);
last++;
if (last - buf >= count)
return -EINVAL;
var.yres_virtual = simple_strtoul(last, &last, 0);
if ((err = activate(fb_info, &var)))
return err;
return count;
}
static ssize_t show_virtual(struct device *device,
struct device_attribute *attr, char *buf)
{
struct fb_info *fb_info = dev_get_drvdata(device);
return snprintf(buf, PAGE_SIZE, "%d,%d\n", fb_info->var.xres_virtual,
fb_info->var.yres_virtual);
}
static ssize_t show_stride(struct device *device,
struct device_attribute *attr, char *buf)
{
struct fb_info *fb_info = dev_get_drvdata(device);
return snprintf(buf, PAGE_SIZE, "%d\n", fb_info->fix.line_length);
}
static ssize_t store_blank(struct device *device,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct fb_info *fb_info = dev_get_drvdata(device);
char *last = NULL;
int err;
console_lock();
fb_info->flags |= FBINFO_MISC_USEREVENT;
err = fb_blank(fb_info, simple_strtoul(buf, &last, 0));
fb_info->flags &= ~FBINFO_MISC_USEREVENT;
console_unlock();
if (err < 0)
return err;
return count;
}
static ssize_t show_blank(struct device *device,
struct device_attribute *attr, char *buf)
{
// struct fb_info *fb_info = dev_get_drvdata(device);
return 0;
}
static ssize_t store_console(struct device *device,
struct device_attribute *attr,
const char *buf, size_t count)
{
// struct fb_info *fb_info = dev_get_drvdata(device);
return 0;
}
static ssize_t show_console(struct device *device,
struct device_attribute *attr, char *buf)
{
// struct fb_info *fb_info = dev_get_drvdata(device);
return 0;
}
static ssize_t store_cursor(struct device *device,
struct device_attribute *attr,
const char *buf, size_t count)
{
// struct fb_info *fb_info = dev_get_drvdata(device);
return 0;
}
static ssize_t show_cursor(struct device *device,
struct device_attribute *attr, char *buf)
{
// struct fb_info *fb_info = dev_get_drvdata(device);
return 0;
}
static ssize_t store_pan(struct device *device,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct fb_info *fb_info = dev_get_drvdata(device);
struct fb_var_screeninfo var;
char *last = NULL;
int err;
var = fb_info->var;
var.xoffset = simple_strtoul(buf, &last, 0);
last++;
if (last - buf >= count)
return -EINVAL;
var.yoffset = simple_strtoul(last, &last, 0);
console_lock();
err = fb_pan_display(fb_info, &var);
console_unlock();
if (err < 0)
return err;
return count;
}
static ssize_t show_pan(struct device *device,
struct device_attribute *attr, char *buf)
{
struct fb_info *fb_info = dev_get_drvdata(device);
return snprintf(buf, PAGE_SIZE, "%d,%d\n", fb_info->var.xoffset,
fb_info->var.yoffset);
}
static ssize_t show_name(struct device *device,
struct device_attribute *attr, char *buf)
{
struct fb_info *fb_info = dev_get_drvdata(device);
return snprintf(buf, PAGE_SIZE, "%s\n", fb_info->fix.id);
}
static ssize_t store_fbstate(struct device *device,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct fb_info *fb_info = dev_get_drvdata(device);
u32 state;
char *last = NULL;
state = simple_strtoul(buf, &last, 0);
fb: avoid possible deadlock caused by fb_set_suspend A lock ordering issue can cause deadlocks: in framebuffer/console code, all needed struct fb_info locks are taken before acquire_console_sem(), in places which need to take console semaphore. But fb_set_suspend is always called with console semaphore held, and inside it we call lock_fb_info which gets the fb_info lock, inverse locking order of what the rest of the code does. This causes a real deadlock issue, when we write to state fb sysfs attribute (which calls fb_set_suspend) while a framebuffer is being unregistered by remove_conflicting_framebuffers, as can be shown by following show blocked state trace on a test program which loads i915 and runs another forked processes writing to state attribute: Test process with semaphore held and trying to get fb_info lock: .. fb-test2 D 0000000000000000 0 237 228 0x00000000 ffff8800774f3d68 0000000000000082 00000000000135c0 00000000000135c0 ffff880000000000 ffff8800774f3fd8 ffff8800774f3fd8 ffff880076ee4530 00000000000135c0 ffff8800774f3fd8 ffff8800774f2000 00000000000135c0 Call Trace: [<ffffffff8141287a>] __mutex_lock_slowpath+0x11a/0x1e0 [<ffffffff814142f2>] ? _raw_spin_lock_irq+0x22/0x40 [<ffffffff814123d3>] mutex_lock+0x23/0x50 [<ffffffff8125dfc5>] lock_fb_info+0x25/0x60 [<ffffffff8125e3f0>] fb_set_suspend+0x20/0x80 [<ffffffff81263e2f>] store_fbstate+0x4f/0x70 [<ffffffff812e7f70>] dev_attr_store+0x20/0x30 [<ffffffff811c46b4>] sysfs_write_file+0xd4/0x160 [<ffffffff81155a26>] vfs_write+0xc6/0x190 [<ffffffff81155d51>] sys_write+0x51/0x90 [<ffffffff8100c012>] system_call_fastpath+0x16/0x1b .. modprobe process stalled because has the fb_info lock (got inside unregister_framebuffer) but waiting for the semaphore held by the test process which is waiting to get the fb_info lock: .. modprobe D 0000000000000000 0 230 218 0x00000000 ffff880077a4d618 0000000000000082 0000000000000001 0000000000000001 ffff880000000000 ffff880077a4dfd8 ffff880077a4dfd8 ffff8800775a2e20 00000000000135c0 ffff880077a4dfd8 ffff880077a4c000 00000000000135c0 Call Trace: [<ffffffff81411fe5>] schedule_timeout+0x215/0x310 [<ffffffff81058051>] ? get_parent_ip+0x11/0x50 [<ffffffff814130dd>] __down+0x6d/0xb0 [<ffffffff81089f71>] down+0x41/0x50 [<ffffffff810629ac>] acquire_console_sem+0x2c/0x50 [<ffffffff812ca53d>] unbind_con_driver+0xad/0x2d0 [<ffffffff8126f5f7>] fbcon_event_notify+0x457/0x890 [<ffffffff814144ff>] ? _raw_spin_unlock_irqrestore+0x1f/0x50 [<ffffffff81058051>] ? get_parent_ip+0x11/0x50 [<ffffffff8141836d>] notifier_call_chain+0x4d/0x70 [<ffffffff8108a3b8>] __blocking_notifier_call_chain+0x58/0x80 [<ffffffff8108a3f6>] blocking_notifier_call_chain+0x16/0x20 [<ffffffff8125dabb>] fb_notifier_call_chain+0x1b/0x20 [<ffffffff8125e6ac>] unregister_framebuffer+0x7c/0x130 [<ffffffff8125e8b3>] remove_conflicting_framebuffers+0x153/0x180 [<ffffffff8125eef3>] register_framebuffer+0x93/0x2c0 [<ffffffffa0331112>] drm_fb_helper_single_fb_probe+0x252/0x2f0 [drm_kms_helper] [<ffffffffa03314a3>] drm_fb_helper_initial_config+0x2f3/0x6d0 [drm_kms_helper] [<ffffffffa03318dd>] ? drm_fb_helper_single_add_all_connectors+0x5d/0x1c0 [drm_kms_helper] [<ffffffffa037b588>] intel_fbdev_init+0xa8/0x160 [i915] [<ffffffffa0343d74>] i915_driver_load+0x854/0x12b0 [i915] [<ffffffffa02f0e7e>] drm_get_pci_dev+0x19e/0x360 [drm] [<ffffffff8141821d>] ? sub_preempt_count+0x9d/0xd0 [<ffffffffa0386f91>] i915_pci_probe+0x15/0x17 [i915] [<ffffffff8124481f>] local_pci_probe+0x5f/0xd0 [<ffffffff81244f89>] pci_device_probe+0x119/0x120 [<ffffffff812eccaa>] ? driver_sysfs_add+0x7a/0xb0 [<ffffffff812ed003>] driver_probe_device+0xa3/0x290 [<ffffffff812ed1f0>] ? __driver_attach+0x0/0xb0 [<ffffffff812ed29b>] __driver_attach+0xab/0xb0 [<ffffffff812ed1f0>] ? __driver_attach+0x0/0xb0 [<ffffffff812ebd3e>] bus_for_each_dev+0x5e/0x90 [<ffffffff812ecc2e>] driver_attach+0x1e/0x20 [<ffffffff812ec6f2>] bus_add_driver+0xe2/0x320 [<ffffffffa03aa000>] ? i915_init+0x0/0x96 [i915] [<ffffffff812ed536>] driver_register+0x76/0x140 [<ffffffffa03aa000>] ? i915_init+0x0/0x96 [i915] [<ffffffff81245216>] __pci_register_driver+0x56/0xd0 [<ffffffffa02f1264>] drm_pci_init+0xe4/0xf0 [drm] [<ffffffffa03aa000>] ? i915_init+0x0/0x96 [i915] [<ffffffffa02e84a8>] drm_init+0x58/0x70 [drm] [<ffffffffa03aa094>] i915_init+0x94/0x96 [i915] [<ffffffff81002194>] do_one_initcall+0x44/0x190 [<ffffffff810a066b>] sys_init_module+0xcb/0x210 [<ffffffff8100c012>] system_call_fastpath+0x16/0x1b .. fb-test2 which reproduces above is available on kernel.org bug #26232. To solve this issue, avoid calling lock_fb_info inside fb_set_suspend, and move it out to where needed (callers of fb_set_suspend must call lock_fb_info before if needed). So far, the only place which needs to call lock_fb_info is store_fbstate, all other places which calls fb_set_suspend are suspend/resume hooks that should not need the lock as they should be run only when processes are already frozen in suspend/resume. References: https://bugzilla.kernel.org/show_bug.cgi?id=26232 Signed-off-by: Herton Ronaldo Krzesinski <herton@mandriva.com.br> Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de> Cc: stable@kernel.org
2011-06-17 19:02:39 +00:00
if (!lock_fb_info(fb_info))
return -ENODEV;
console_lock();
fb_set_suspend(fb_info, (int)state);
console_unlock();
fb: avoid possible deadlock caused by fb_set_suspend A lock ordering issue can cause deadlocks: in framebuffer/console code, all needed struct fb_info locks are taken before acquire_console_sem(), in places which need to take console semaphore. But fb_set_suspend is always called with console semaphore held, and inside it we call lock_fb_info which gets the fb_info lock, inverse locking order of what the rest of the code does. This causes a real deadlock issue, when we write to state fb sysfs attribute (which calls fb_set_suspend) while a framebuffer is being unregistered by remove_conflicting_framebuffers, as can be shown by following show blocked state trace on a test program which loads i915 and runs another forked processes writing to state attribute: Test process with semaphore held and trying to get fb_info lock: .. fb-test2 D 0000000000000000 0 237 228 0x00000000 ffff8800774f3d68 0000000000000082 00000000000135c0 00000000000135c0 ffff880000000000 ffff8800774f3fd8 ffff8800774f3fd8 ffff880076ee4530 00000000000135c0 ffff8800774f3fd8 ffff8800774f2000 00000000000135c0 Call Trace: [<ffffffff8141287a>] __mutex_lock_slowpath+0x11a/0x1e0 [<ffffffff814142f2>] ? _raw_spin_lock_irq+0x22/0x40 [<ffffffff814123d3>] mutex_lock+0x23/0x50 [<ffffffff8125dfc5>] lock_fb_info+0x25/0x60 [<ffffffff8125e3f0>] fb_set_suspend+0x20/0x80 [<ffffffff81263e2f>] store_fbstate+0x4f/0x70 [<ffffffff812e7f70>] dev_attr_store+0x20/0x30 [<ffffffff811c46b4>] sysfs_write_file+0xd4/0x160 [<ffffffff81155a26>] vfs_write+0xc6/0x190 [<ffffffff81155d51>] sys_write+0x51/0x90 [<ffffffff8100c012>] system_call_fastpath+0x16/0x1b .. modprobe process stalled because has the fb_info lock (got inside unregister_framebuffer) but waiting for the semaphore held by the test process which is waiting to get the fb_info lock: .. modprobe D 0000000000000000 0 230 218 0x00000000 ffff880077a4d618 0000000000000082 0000000000000001 0000000000000001 ffff880000000000 ffff880077a4dfd8 ffff880077a4dfd8 ffff8800775a2e20 00000000000135c0 ffff880077a4dfd8 ffff880077a4c000 00000000000135c0 Call Trace: [<ffffffff81411fe5>] schedule_timeout+0x215/0x310 [<ffffffff81058051>] ? get_parent_ip+0x11/0x50 [<ffffffff814130dd>] __down+0x6d/0xb0 [<ffffffff81089f71>] down+0x41/0x50 [<ffffffff810629ac>] acquire_console_sem+0x2c/0x50 [<ffffffff812ca53d>] unbind_con_driver+0xad/0x2d0 [<ffffffff8126f5f7>] fbcon_event_notify+0x457/0x890 [<ffffffff814144ff>] ? _raw_spin_unlock_irqrestore+0x1f/0x50 [<ffffffff81058051>] ? get_parent_ip+0x11/0x50 [<ffffffff8141836d>] notifier_call_chain+0x4d/0x70 [<ffffffff8108a3b8>] __blocking_notifier_call_chain+0x58/0x80 [<ffffffff8108a3f6>] blocking_notifier_call_chain+0x16/0x20 [<ffffffff8125dabb>] fb_notifier_call_chain+0x1b/0x20 [<ffffffff8125e6ac>] unregister_framebuffer+0x7c/0x130 [<ffffffff8125e8b3>] remove_conflicting_framebuffers+0x153/0x180 [<ffffffff8125eef3>] register_framebuffer+0x93/0x2c0 [<ffffffffa0331112>] drm_fb_helper_single_fb_probe+0x252/0x2f0 [drm_kms_helper] [<ffffffffa03314a3>] drm_fb_helper_initial_config+0x2f3/0x6d0 [drm_kms_helper] [<ffffffffa03318dd>] ? drm_fb_helper_single_add_all_connectors+0x5d/0x1c0 [drm_kms_helper] [<ffffffffa037b588>] intel_fbdev_init+0xa8/0x160 [i915] [<ffffffffa0343d74>] i915_driver_load+0x854/0x12b0 [i915] [<ffffffffa02f0e7e>] drm_get_pci_dev+0x19e/0x360 [drm] [<ffffffff8141821d>] ? sub_preempt_count+0x9d/0xd0 [<ffffffffa0386f91>] i915_pci_probe+0x15/0x17 [i915] [<ffffffff8124481f>] local_pci_probe+0x5f/0xd0 [<ffffffff81244f89>] pci_device_probe+0x119/0x120 [<ffffffff812eccaa>] ? driver_sysfs_add+0x7a/0xb0 [<ffffffff812ed003>] driver_probe_device+0xa3/0x290 [<ffffffff812ed1f0>] ? __driver_attach+0x0/0xb0 [<ffffffff812ed29b>] __driver_attach+0xab/0xb0 [<ffffffff812ed1f0>] ? __driver_attach+0x0/0xb0 [<ffffffff812ebd3e>] bus_for_each_dev+0x5e/0x90 [<ffffffff812ecc2e>] driver_attach+0x1e/0x20 [<ffffffff812ec6f2>] bus_add_driver+0xe2/0x320 [<ffffffffa03aa000>] ? i915_init+0x0/0x96 [i915] [<ffffffff812ed536>] driver_register+0x76/0x140 [<ffffffffa03aa000>] ? i915_init+0x0/0x96 [i915] [<ffffffff81245216>] __pci_register_driver+0x56/0xd0 [<ffffffffa02f1264>] drm_pci_init+0xe4/0xf0 [drm] [<ffffffffa03aa000>] ? i915_init+0x0/0x96 [i915] [<ffffffffa02e84a8>] drm_init+0x58/0x70 [drm] [<ffffffffa03aa094>] i915_init+0x94/0x96 [i915] [<ffffffff81002194>] do_one_initcall+0x44/0x190 [<ffffffff810a066b>] sys_init_module+0xcb/0x210 [<ffffffff8100c012>] system_call_fastpath+0x16/0x1b .. fb-test2 which reproduces above is available on kernel.org bug #26232. To solve this issue, avoid calling lock_fb_info inside fb_set_suspend, and move it out to where needed (callers of fb_set_suspend must call lock_fb_info before if needed). So far, the only place which needs to call lock_fb_info is store_fbstate, all other places which calls fb_set_suspend are suspend/resume hooks that should not need the lock as they should be run only when processes are already frozen in suspend/resume. References: https://bugzilla.kernel.org/show_bug.cgi?id=26232 Signed-off-by: Herton Ronaldo Krzesinski <herton@mandriva.com.br> Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de> Cc: stable@kernel.org
2011-06-17 19:02:39 +00:00
unlock_fb_info(fb_info);
return count;
}
static ssize_t show_fbstate(struct device *device,
struct device_attribute *attr, char *buf)
{
struct fb_info *fb_info = dev_get_drvdata(device);
return snprintf(buf, PAGE_SIZE, "%d\n", fb_info->state);
}
#ifdef CONFIG_FB_BACKLIGHT
static ssize_t store_bl_curve(struct device *device,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct fb_info *fb_info = dev_get_drvdata(device);
u8 tmp_curve[FB_BACKLIGHT_LEVELS];
unsigned int i;
/* Some drivers don't use framebuffer_alloc(), but those also
* don't have backlights.
*/
if (!fb_info || !fb_info->bl_dev)
return -ENODEV;
if (count != (FB_BACKLIGHT_LEVELS / 8 * 24))
return -EINVAL;
for (i = 0; i < (FB_BACKLIGHT_LEVELS / 8); ++i)
if (sscanf(&buf[i * 24],
"%2hhx %2hhx %2hhx %2hhx %2hhx %2hhx %2hhx %2hhx\n",
&tmp_curve[i * 8 + 0],
&tmp_curve[i * 8 + 1],
&tmp_curve[i * 8 + 2],
&tmp_curve[i * 8 + 3],
&tmp_curve[i * 8 + 4],
&tmp_curve[i * 8 + 5],
&tmp_curve[i * 8 + 6],
&tmp_curve[i * 8 + 7]) != 8)
return -EINVAL;
/* If there has been an error in the input data, we won't
* reach this loop.
*/
mutex_lock(&fb_info->bl_curve_mutex);
for (i = 0; i < FB_BACKLIGHT_LEVELS; ++i)
fb_info->bl_curve[i] = tmp_curve[i];
mutex_unlock(&fb_info->bl_curve_mutex);
return count;
}
static ssize_t show_bl_curve(struct device *device,
struct device_attribute *attr, char *buf)
{
struct fb_info *fb_info = dev_get_drvdata(device);
ssize_t len = 0;
unsigned int i;
/* Some drivers don't use framebuffer_alloc(), but those also
* don't have backlights.
*/
if (!fb_info || !fb_info->bl_dev)
return -ENODEV;
mutex_lock(&fb_info->bl_curve_mutex);
for (i = 0; i < FB_BACKLIGHT_LEVELS; i += 8)
len += snprintf(&buf[len], PAGE_SIZE,
"%02x %02x %02x %02x %02x %02x %02x %02x\n",
fb_info->bl_curve[i + 0],
fb_info->bl_curve[i + 1],
fb_info->bl_curve[i + 2],
fb_info->bl_curve[i + 3],
fb_info->bl_curve[i + 4],
fb_info->bl_curve[i + 5],
fb_info->bl_curve[i + 6],
fb_info->bl_curve[i + 7]);
mutex_unlock(&fb_info->bl_curve_mutex);
return len;
}
#endif
/* When cmap is added back in it should be a binary attribute
* not a text one. Consideration should also be given to converting
* fbdev to use configfs instead of sysfs */
static struct device_attribute device_attrs[] = {
__ATTR(bits_per_pixel, S_IRUGO|S_IWUSR, show_bpp, store_bpp),
__ATTR(blank, S_IRUGO|S_IWUSR, show_blank, store_blank),
__ATTR(console, S_IRUGO|S_IWUSR, show_console, store_console),
__ATTR(cursor, S_IRUGO|S_IWUSR, show_cursor, store_cursor),
__ATTR(mode, S_IRUGO|S_IWUSR, show_mode, store_mode),
__ATTR(modes, S_IRUGO|S_IWUSR, show_modes, store_modes),
__ATTR(pan, S_IRUGO|S_IWUSR, show_pan, store_pan),
__ATTR(virtual_size, S_IRUGO|S_IWUSR, show_virtual, store_virtual),
__ATTR(name, S_IRUGO, show_name, NULL),
__ATTR(stride, S_IRUGO, show_stride, NULL),
__ATTR(rotate, S_IRUGO|S_IWUSR, show_rotate, store_rotate),
__ATTR(state, S_IRUGO|S_IWUSR, show_fbstate, store_fbstate),
#ifdef CONFIG_FB_BACKLIGHT
__ATTR(bl_curve, S_IRUGO|S_IWUSR, show_bl_curve, store_bl_curve),
#endif
};
int fb_init_device(struct fb_info *fb_info)
{
int i, error = 0;
dev_set_drvdata(fb_info->dev, fb_info);
fb_info->class_flag |= FB_SYSFS_FLAG_ATTR;
for (i = 0; i < ARRAY_SIZE(device_attrs); i++) {
error = device_create_file(fb_info->dev, &device_attrs[i]);
if (error)
break;
}
if (error) {
while (--i >= 0)
device_remove_file(fb_info->dev, &device_attrs[i]);
fb_info->class_flag &= ~FB_SYSFS_FLAG_ATTR;
}
return 0;
}
void fb_cleanup_device(struct fb_info *fb_info)
{
unsigned int i;
if (fb_info->class_flag & FB_SYSFS_FLAG_ATTR) {
for (i = 0; i < ARRAY_SIZE(device_attrs); i++)
device_remove_file(fb_info->dev, &device_attrs[i]);
fb_info->class_flag &= ~FB_SYSFS_FLAG_ATTR;
}
}
#ifdef CONFIG_FB_BACKLIGHT
/* This function generates a linear backlight curve
*
* 0: off
* 1-7: min
* 8-127: linear from min to max
*/
void fb_bl_default_curve(struct fb_info *fb_info, u8 off, u8 min, u8 max)
{
unsigned int i, flat, count, range = (max - min);
mutex_lock(&fb_info->bl_curve_mutex);
fb_info->bl_curve[0] = off;
for (flat = 1; flat < (FB_BACKLIGHT_LEVELS / 16); ++flat)
fb_info->bl_curve[flat] = min;
count = FB_BACKLIGHT_LEVELS * 15 / 16;
for (i = 0; i < count; ++i)
fb_info->bl_curve[flat + i] = min + (range * (i + 1) / count);
mutex_unlock(&fb_info->bl_curve_mutex);
}
EXPORT_SYMBOL_GPL(fb_bl_default_curve);
#endif