OpenCloudOS-Kernel/drivers/gpu/drm/vmwgfx/vmwgfx_fb.c

846 lines
20 KiB
C

/**************************************************************************
*
* Copyright © 2007 David Airlie
* Copyright © 2009-2015 VMware, Inc., Palo Alto, CA., USA
* All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sub license, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial portions
* of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
* THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
* USE OR OTHER DEALINGS IN THE SOFTWARE.
*
**************************************************************************/
#include <linux/pci.h>
#include <drm/drm_fourcc.h>
#include <drm/ttm/ttm_placement.h>
#include "vmwgfx_drv.h"
#include "vmwgfx_kms.h"
#define VMW_DIRTY_DELAY (HZ / 30)
struct vmw_fb_par {
struct vmw_private *vmw_priv;
void *vmalloc;
struct mutex bo_mutex;
struct vmw_buffer_object *vmw_bo;
unsigned bo_size;
struct drm_framebuffer *set_fb;
struct drm_display_mode *set_mode;
u32 fb_x;
u32 fb_y;
bool bo_iowrite;
u32 pseudo_palette[17];
unsigned max_width;
unsigned max_height;
struct {
spinlock_t lock;
bool active;
unsigned x1;
unsigned y1;
unsigned x2;
unsigned y2;
} dirty;
struct drm_crtc *crtc;
struct drm_connector *con;
struct delayed_work local_work;
};
static int vmw_fb_setcolreg(unsigned regno, unsigned red, unsigned green,
unsigned blue, unsigned transp,
struct fb_info *info)
{
struct vmw_fb_par *par = info->par;
u32 *pal = par->pseudo_palette;
if (regno > 15) {
DRM_ERROR("Bad regno %u.\n", regno);
return 1;
}
switch (par->set_fb->format->depth) {
case 24:
case 32:
pal[regno] = ((red & 0xff00) << 8) |
(green & 0xff00) |
((blue & 0xff00) >> 8);
break;
default:
DRM_ERROR("Bad depth %u, bpp %u.\n",
par->set_fb->format->depth,
par->set_fb->format->cpp[0] * 8);
return 1;
}
return 0;
}
static int vmw_fb_check_var(struct fb_var_screeninfo *var,
struct fb_info *info)
{
int depth = var->bits_per_pixel;
struct vmw_fb_par *par = info->par;
struct vmw_private *vmw_priv = par->vmw_priv;
switch (var->bits_per_pixel) {
case 32:
depth = (var->transp.length > 0) ? 32 : 24;
break;
default:
DRM_ERROR("Bad bpp %u.\n", var->bits_per_pixel);
return -EINVAL;
}
switch (depth) {
case 24:
var->red.offset = 16;
var->green.offset = 8;
var->blue.offset = 0;
var->red.length = 8;
var->green.length = 8;
var->blue.length = 8;
var->transp.length = 0;
var->transp.offset = 0;
break;
case 32:
var->red.offset = 16;
var->green.offset = 8;
var->blue.offset = 0;
var->red.length = 8;
var->green.length = 8;
var->blue.length = 8;
var->transp.length = 8;
var->transp.offset = 24;
break;
default:
DRM_ERROR("Bad depth %u.\n", depth);
return -EINVAL;
}
if ((var->xoffset + var->xres) > par->max_width ||
(var->yoffset + var->yres) > par->max_height) {
DRM_ERROR("Requested geom can not fit in framebuffer\n");
return -EINVAL;
}
if (!vmw_kms_validate_mode_vram(vmw_priv,
var->xres * var->bits_per_pixel/8,
var->yoffset + var->yres)) {
DRM_ERROR("Requested geom can not fit in framebuffer\n");
return -EINVAL;
}
return 0;
}
static int vmw_fb_blank(int blank, struct fb_info *info)
{
return 0;
}
/**
* vmw_fb_dirty_flush - flush dirty regions to the kms framebuffer
*
* @work: The struct work_struct associated with this task.
*
* This function flushes the dirty regions of the vmalloc framebuffer to the
* kms framebuffer, and if the kms framebuffer is visible, also updated the
* corresponding displays. Note that this function runs even if the kms
* framebuffer is not bound to a crtc and thus not visible, but it's turned
* off during hibernation using the par->dirty.active bool.
*/
static void vmw_fb_dirty_flush(struct work_struct *work)
{
struct vmw_fb_par *par = container_of(work, struct vmw_fb_par,
local_work.work);
struct vmw_private *vmw_priv = par->vmw_priv;
struct fb_info *info = vmw_priv->fb_info;
unsigned long irq_flags;
s32 dst_x1, dst_x2, dst_y1, dst_y2, w = 0, h = 0;
u32 cpp, max_x, max_y;
struct drm_clip_rect clip;
struct drm_framebuffer *cur_fb;
u8 *src_ptr, *dst_ptr;
struct vmw_buffer_object *vbo = par->vmw_bo;
void *virtual;
if (!READ_ONCE(par->dirty.active))
return;
mutex_lock(&par->bo_mutex);
cur_fb = par->set_fb;
if (!cur_fb)
goto out_unlock;
(void) ttm_read_lock(&vmw_priv->reservation_sem, false);
(void) ttm_bo_reserve(&vbo->base, false, false, NULL);
virtual = vmw_bo_map_and_cache(vbo);
if (!virtual)
goto out_unreserve;
spin_lock_irqsave(&par->dirty.lock, irq_flags);
if (!par->dirty.active) {
spin_unlock_irqrestore(&par->dirty.lock, irq_flags);
goto out_unreserve;
}
/*
* Handle panning when copying from vmalloc to framebuffer.
* Clip dirty area to framebuffer.
*/
cpp = cur_fb->format->cpp[0];
max_x = par->fb_x + cur_fb->width;
max_y = par->fb_y + cur_fb->height;
dst_x1 = par->dirty.x1 - par->fb_x;
dst_y1 = par->dirty.y1 - par->fb_y;
dst_x1 = max_t(s32, dst_x1, 0);
dst_y1 = max_t(s32, dst_y1, 0);
dst_x2 = par->dirty.x2 - par->fb_x;
dst_y2 = par->dirty.y2 - par->fb_y;
dst_x2 = min_t(s32, dst_x2, max_x);
dst_y2 = min_t(s32, dst_y2, max_y);
w = dst_x2 - dst_x1;
h = dst_y2 - dst_y1;
w = max_t(s32, 0, w);
h = max_t(s32, 0, h);
par->dirty.x1 = par->dirty.x2 = 0;
par->dirty.y1 = par->dirty.y2 = 0;
spin_unlock_irqrestore(&par->dirty.lock, irq_flags);
if (w && h) {
dst_ptr = (u8 *)virtual +
(dst_y1 * par->set_fb->pitches[0] + dst_x1 * cpp);
src_ptr = (u8 *)par->vmalloc +
((dst_y1 + par->fb_y) * info->fix.line_length +
(dst_x1 + par->fb_x) * cpp);
while (h-- > 0) {
memcpy(dst_ptr, src_ptr, w*cpp);
dst_ptr += par->set_fb->pitches[0];
src_ptr += info->fix.line_length;
}
clip.x1 = dst_x1;
clip.x2 = dst_x2;
clip.y1 = dst_y1;
clip.y2 = dst_y2;
}
out_unreserve:
ttm_bo_unreserve(&vbo->base);
ttm_read_unlock(&vmw_priv->reservation_sem);
if (w && h) {
WARN_ON_ONCE(par->set_fb->funcs->dirty(cur_fb, NULL, 0, 0,
&clip, 1));
vmw_cmd_flush(vmw_priv, false);
}
out_unlock:
mutex_unlock(&par->bo_mutex);
}
static void vmw_fb_dirty_mark(struct vmw_fb_par *par,
unsigned x1, unsigned y1,
unsigned width, unsigned height)
{
unsigned long flags;
unsigned x2 = x1 + width;
unsigned y2 = y1 + height;
spin_lock_irqsave(&par->dirty.lock, flags);
if (par->dirty.x1 == par->dirty.x2) {
par->dirty.x1 = x1;
par->dirty.y1 = y1;
par->dirty.x2 = x2;
par->dirty.y2 = y2;
/* if we are active start the dirty work
* we share the work with the defio system */
if (par->dirty.active)
schedule_delayed_work(&par->local_work,
VMW_DIRTY_DELAY);
} else {
if (x1 < par->dirty.x1)
par->dirty.x1 = x1;
if (y1 < par->dirty.y1)
par->dirty.y1 = y1;
if (x2 > par->dirty.x2)
par->dirty.x2 = x2;
if (y2 > par->dirty.y2)
par->dirty.y2 = y2;
}
spin_unlock_irqrestore(&par->dirty.lock, flags);
}
static int vmw_fb_pan_display(struct fb_var_screeninfo *var,
struct fb_info *info)
{
struct vmw_fb_par *par = info->par;
if ((var->xoffset + var->xres) > var->xres_virtual ||
(var->yoffset + var->yres) > var->yres_virtual) {
DRM_ERROR("Requested panning can not fit in framebuffer\n");
return -EINVAL;
}
mutex_lock(&par->bo_mutex);
par->fb_x = var->xoffset;
par->fb_y = var->yoffset;
if (par->set_fb)
vmw_fb_dirty_mark(par, par->fb_x, par->fb_y, par->set_fb->width,
par->set_fb->height);
mutex_unlock(&par->bo_mutex);
return 0;
}
static void vmw_deferred_io(struct fb_info *info,
struct list_head *pagelist)
{
struct vmw_fb_par *par = info->par;
unsigned long start, end, min, max;
unsigned long flags;
struct page *page;
int y1, y2;
min = ULONG_MAX;
max = 0;
list_for_each_entry(page, pagelist, lru) {
start = page->index << PAGE_SHIFT;
end = start + PAGE_SIZE - 1;
min = min(min, start);
max = max(max, end);
}
if (min < max) {
y1 = min / info->fix.line_length;
y2 = (max / info->fix.line_length) + 1;
spin_lock_irqsave(&par->dirty.lock, flags);
par->dirty.x1 = 0;
par->dirty.y1 = y1;
par->dirty.x2 = info->var.xres;
par->dirty.y2 = y2;
spin_unlock_irqrestore(&par->dirty.lock, flags);
/*
* Since we've already waited on this work once, try to
* execute asap.
*/
cancel_delayed_work(&par->local_work);
schedule_delayed_work(&par->local_work, 0);
}
};
static struct fb_deferred_io vmw_defio = {
.delay = VMW_DIRTY_DELAY,
.deferred_io = vmw_deferred_io,
};
/*
* Draw code
*/
static void vmw_fb_fillrect(struct fb_info *info, const struct fb_fillrect *rect)
{
cfb_fillrect(info, rect);
vmw_fb_dirty_mark(info->par, rect->dx, rect->dy,
rect->width, rect->height);
}
static void vmw_fb_copyarea(struct fb_info *info, const struct fb_copyarea *region)
{
cfb_copyarea(info, region);
vmw_fb_dirty_mark(info->par, region->dx, region->dy,
region->width, region->height);
}
static void vmw_fb_imageblit(struct fb_info *info, const struct fb_image *image)
{
cfb_imageblit(info, image);
vmw_fb_dirty_mark(info->par, image->dx, image->dy,
image->width, image->height);
}
/*
* Bring up code
*/
static int vmw_fb_create_bo(struct vmw_private *vmw_priv,
size_t size, struct vmw_buffer_object **out)
{
struct vmw_buffer_object *vmw_bo;
int ret;
(void) ttm_write_lock(&vmw_priv->reservation_sem, false);
vmw_bo = kmalloc(sizeof(*vmw_bo), GFP_KERNEL);
if (!vmw_bo) {
ret = -ENOMEM;
goto err_unlock;
}
ret = vmw_bo_init(vmw_priv, vmw_bo, size,
&vmw_sys_placement,
false, false,
&vmw_bo_bo_free);
if (unlikely(ret != 0))
goto err_unlock; /* init frees the buffer on failure */
*out = vmw_bo;
ttm_write_unlock(&vmw_priv->reservation_sem);
return 0;
err_unlock:
ttm_write_unlock(&vmw_priv->reservation_sem);
return ret;
}
static int vmw_fb_compute_depth(struct fb_var_screeninfo *var,
int *depth)
{
switch (var->bits_per_pixel) {
case 32:
*depth = (var->transp.length > 0) ? 32 : 24;
break;
default:
DRM_ERROR("Bad bpp %u.\n", var->bits_per_pixel);
return -EINVAL;
}
return 0;
}
static int vmwgfx_set_config_internal(struct drm_mode_set *set)
{
struct drm_crtc *crtc = set->crtc;
struct drm_modeset_acquire_ctx ctx;
int ret;
drm_modeset_acquire_init(&ctx, 0);
restart:
ret = crtc->funcs->set_config(set, &ctx);
if (ret == -EDEADLK) {
drm_modeset_backoff(&ctx);
goto restart;
}
drm_modeset_drop_locks(&ctx);
drm_modeset_acquire_fini(&ctx);
return ret;
}
static int vmw_fb_kms_detach(struct vmw_fb_par *par,
bool detach_bo,
bool unref_bo)
{
struct drm_framebuffer *cur_fb = par->set_fb;
int ret;
/* Detach the KMS framebuffer from crtcs */
if (par->set_mode) {
struct drm_mode_set set;
set.crtc = par->crtc;
set.x = 0;
set.y = 0;
set.mode = NULL;
set.fb = NULL;
set.num_connectors = 0;
set.connectors = &par->con;
ret = vmwgfx_set_config_internal(&set);
if (ret) {
DRM_ERROR("Could not unset a mode.\n");
return ret;
}
drm_mode_destroy(&par->vmw_priv->drm, par->set_mode);
par->set_mode = NULL;
}
if (cur_fb) {
drm_framebuffer_put(cur_fb);
par->set_fb = NULL;
}
if (par->vmw_bo && detach_bo && unref_bo)
vmw_bo_unreference(&par->vmw_bo);
return 0;
}
static int vmw_fb_kms_framebuffer(struct fb_info *info)
{
struct drm_mode_fb_cmd2 mode_cmd;
struct vmw_fb_par *par = info->par;
struct fb_var_screeninfo *var = &info->var;
struct drm_framebuffer *cur_fb;
struct vmw_framebuffer *vfb;
int ret = 0, depth;
size_t new_bo_size;
ret = vmw_fb_compute_depth(var, &depth);
if (ret)
return ret;
mode_cmd.width = var->xres;
mode_cmd.height = var->yres;
mode_cmd.pitches[0] = ((var->bits_per_pixel + 7) / 8) * mode_cmd.width;
mode_cmd.pixel_format =
drm_mode_legacy_fb_format(var->bits_per_pixel, depth);
cur_fb = par->set_fb;
if (cur_fb && cur_fb->width == mode_cmd.width &&
cur_fb->height == mode_cmd.height &&
cur_fb->format->format == mode_cmd.pixel_format &&
cur_fb->pitches[0] == mode_cmd.pitches[0])
return 0;
/* Need new buffer object ? */
new_bo_size = (size_t) mode_cmd.pitches[0] * (size_t) mode_cmd.height;
ret = vmw_fb_kms_detach(par,
par->bo_size < new_bo_size ||
par->bo_size > 2*new_bo_size,
true);
if (ret)
return ret;
if (!par->vmw_bo) {
ret = vmw_fb_create_bo(par->vmw_priv, new_bo_size,
&par->vmw_bo);
if (ret) {
DRM_ERROR("Failed creating a buffer object for "
"fbdev.\n");
return ret;
}
par->bo_size = new_bo_size;
}
vfb = vmw_kms_new_framebuffer(par->vmw_priv, par->vmw_bo, NULL,
true, &mode_cmd);
if (IS_ERR(vfb))
return PTR_ERR(vfb);
par->set_fb = &vfb->base;
return 0;
}
static int vmw_fb_set_par(struct fb_info *info)
{
struct vmw_fb_par *par = info->par;
struct vmw_private *vmw_priv = par->vmw_priv;
struct drm_mode_set set;
struct fb_var_screeninfo *var = &info->var;
struct drm_display_mode new_mode = { DRM_MODE("fb_mode",
DRM_MODE_TYPE_DRIVER,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_PVSYNC)
};
struct drm_display_mode *mode;
int ret;
mode = drm_mode_duplicate(&vmw_priv->drm, &new_mode);
if (!mode) {
DRM_ERROR("Could not create new fb mode.\n");
return -ENOMEM;
}
mode->hdisplay = var->xres;
mode->vdisplay = var->yres;
vmw_guess_mode_timing(mode);
if (!vmw_kms_validate_mode_vram(vmw_priv,
mode->hdisplay *
DIV_ROUND_UP(var->bits_per_pixel, 8),
mode->vdisplay)) {
drm_mode_destroy(&vmw_priv->drm, mode);
return -EINVAL;
}
mutex_lock(&par->bo_mutex);
ret = vmw_fb_kms_framebuffer(info);
if (ret)
goto out_unlock;
par->fb_x = var->xoffset;
par->fb_y = var->yoffset;
set.crtc = par->crtc;
set.x = 0;
set.y = 0;
set.mode = mode;
set.fb = par->set_fb;
set.num_connectors = 1;
set.connectors = &par->con;
ret = vmwgfx_set_config_internal(&set);
if (ret)
goto out_unlock;
vmw_fb_dirty_mark(par, par->fb_x, par->fb_y,
par->set_fb->width, par->set_fb->height);
/* If there already was stuff dirty we wont
* schedule a new work, so lets do it now */
schedule_delayed_work(&par->local_work, 0);
out_unlock:
if (par->set_mode)
drm_mode_destroy(&vmw_priv->drm, par->set_mode);
par->set_mode = mode;
mutex_unlock(&par->bo_mutex);
return ret;
}
static const struct fb_ops vmw_fb_ops = {
.owner = THIS_MODULE,
.fb_check_var = vmw_fb_check_var,
.fb_set_par = vmw_fb_set_par,
.fb_setcolreg = vmw_fb_setcolreg,
.fb_fillrect = vmw_fb_fillrect,
.fb_copyarea = vmw_fb_copyarea,
.fb_imageblit = vmw_fb_imageblit,
.fb_pan_display = vmw_fb_pan_display,
.fb_blank = vmw_fb_blank,
};
int vmw_fb_init(struct vmw_private *vmw_priv)
{
struct device *device = vmw_priv->drm.dev;
struct vmw_fb_par *par;
struct fb_info *info;
unsigned fb_width, fb_height;
unsigned int fb_bpp, fb_pitch, fb_size;
struct drm_display_mode *init_mode;
int ret;
fb_bpp = 32;
/* XXX As shouldn't these be as well. */
fb_width = min(vmw_priv->fb_max_width, (unsigned)2048);
fb_height = min(vmw_priv->fb_max_height, (unsigned)2048);
fb_pitch = fb_width * fb_bpp / 8;
fb_size = fb_pitch * fb_height;
info = framebuffer_alloc(sizeof(*par), device);
if (!info)
return -ENOMEM;
/*
* Par
*/
vmw_priv->fb_info = info;
par = info->par;
memset(par, 0, sizeof(*par));
INIT_DELAYED_WORK(&par->local_work, &vmw_fb_dirty_flush);
par->vmw_priv = vmw_priv;
par->vmalloc = NULL;
par->max_width = fb_width;
par->max_height = fb_height;
ret = vmw_kms_fbdev_init_data(vmw_priv, 0, par->max_width,
par->max_height, &par->con,
&par->crtc, &init_mode);
if (ret)
goto err_kms;
info->var.xres = init_mode->hdisplay;
info->var.yres = init_mode->vdisplay;
/*
* Create buffers and alloc memory
*/
par->vmalloc = vzalloc(fb_size);
if (unlikely(par->vmalloc == NULL)) {
ret = -ENOMEM;
goto err_free;
}
/*
* Fixed and var
*/
strcpy(info->fix.id, "svgadrmfb");
info->fix.type = FB_TYPE_PACKED_PIXELS;
info->fix.visual = FB_VISUAL_TRUECOLOR;
info->fix.type_aux = 0;
info->fix.xpanstep = 1; /* doing it in hw */
info->fix.ypanstep = 1; /* doing it in hw */
info->fix.ywrapstep = 0;
info->fix.accel = FB_ACCEL_NONE;
info->fix.line_length = fb_pitch;
info->fix.smem_start = 0;
info->fix.smem_len = fb_size;
info->pseudo_palette = par->pseudo_palette;
info->screen_base = (char __iomem *)par->vmalloc;
info->screen_size = fb_size;
info->fbops = &vmw_fb_ops;
/* 24 depth per default */
info->var.red.offset = 16;
info->var.green.offset = 8;
info->var.blue.offset = 0;
info->var.red.length = 8;
info->var.green.length = 8;
info->var.blue.length = 8;
info->var.transp.offset = 0;
info->var.transp.length = 0;
info->var.xres_virtual = fb_width;
info->var.yres_virtual = fb_height;
info->var.bits_per_pixel = fb_bpp;
info->var.xoffset = 0;
info->var.yoffset = 0;
info->var.activate = FB_ACTIVATE_NOW;
info->var.height = -1;
info->var.width = -1;
/* Use default scratch pixmap (info->pixmap.flags = FB_PIXMAP_SYSTEM) */
info->apertures = alloc_apertures(1);
if (!info->apertures) {
ret = -ENOMEM;
goto err_aper;
}
info->apertures->ranges[0].base = vmw_priv->vram_start;
info->apertures->ranges[0].size = vmw_priv->vram_size;
/*
* Dirty & Deferred IO
*/
par->dirty.x1 = par->dirty.x2 = 0;
par->dirty.y1 = par->dirty.y2 = 0;
par->dirty.active = true;
spin_lock_init(&par->dirty.lock);
mutex_init(&par->bo_mutex);
info->fbdefio = &vmw_defio;
fb_deferred_io_init(info);
ret = register_framebuffer(info);
if (unlikely(ret != 0))
goto err_defio;
vmw_fb_set_par(info);
return 0;
err_defio:
fb_deferred_io_cleanup(info);
err_aper:
err_free:
vfree(par->vmalloc);
err_kms:
framebuffer_release(info);
vmw_priv->fb_info = NULL;
return ret;
}
int vmw_fb_close(struct vmw_private *vmw_priv)
{
struct fb_info *info;
struct vmw_fb_par *par;
if (!vmw_priv->fb_info)
return 0;
info = vmw_priv->fb_info;
par = info->par;
/* ??? order */
fb_deferred_io_cleanup(info);
cancel_delayed_work_sync(&par->local_work);
unregister_framebuffer(info);
mutex_lock(&par->bo_mutex);
(void) vmw_fb_kms_detach(par, true, true);
mutex_unlock(&par->bo_mutex);
vfree(par->vmalloc);
framebuffer_release(info);
return 0;
}
int vmw_fb_off(struct vmw_private *vmw_priv)
{
struct fb_info *info;
struct vmw_fb_par *par;
unsigned long flags;
if (!vmw_priv->fb_info)
return -EINVAL;
info = vmw_priv->fb_info;
par = info->par;
spin_lock_irqsave(&par->dirty.lock, flags);
par->dirty.active = false;
spin_unlock_irqrestore(&par->dirty.lock, flags);
flush_delayed_work(&info->deferred_work);
flush_delayed_work(&par->local_work);
return 0;
}
int vmw_fb_on(struct vmw_private *vmw_priv)
{
struct fb_info *info;
struct vmw_fb_par *par;
unsigned long flags;
if (!vmw_priv->fb_info)
return -EINVAL;
info = vmw_priv->fb_info;
par = info->par;
spin_lock_irqsave(&par->dirty.lock, flags);
par->dirty.active = true;
spin_unlock_irqrestore(&par->dirty.lock, flags);
/*
* Need to reschedule a dirty update, because otherwise that's
* only done in dirty_mark() if the previous coalesced
* dirty region was empty.
*/
schedule_delayed_work(&par->local_work, 0);
return 0;
}