diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index d06ce0e92d660e02c2c49fff8400bd73cf3d7c23..dd1d72d58b35ad86cff0d651fc774dd78d60e079 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -717,13 +717,13 @@ void drm_fb_helper_deferred_io(struct fb_info *info,
struct list_head *pagelist)
{
unsigned long start, end, min, max;
- struct page *page;
+ struct fb_deferred_io_pageref *pageref;
struct drm_rect damage_area;
min = ULONG_MAX;
max = 0;
- list_for_each_entry(page, pagelist, lru) {
- start = page->index << PAGE_SHIFT;
+ list_for_each_entry(pageref, pagelist, list) {
+ start = pageref->offset;
end = start + PAGE_SIZE;
min = min(min, start);
max = max(max, end);
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_fb.c b/drivers/gpu/drm/vmwgfx/vmwgfx_fb.c
index 02a4a4fa3da3fd47c52e0a42dc1a83312e1de34e..db02e17e12b6083b8fcdc6df52b20af84a47a994 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_fb.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_fb.c
@@ -322,12 +322,13 @@ static void vmw_deferred_io(struct fb_info *info,
struct vmw_fb_par *par = info->par;
unsigned long start, end, min, max;
unsigned long flags;
- struct page *page;
+ struct fb_deferred_io_pageref *pageref;
int y1, y2;
min = ULONG_MAX;
max = 0;
- list_for_each_entry(page, pagelist, lru) {
+ list_for_each_entry(pageref, pagelist, list) {
+ struct page *page = pageref->page;
start = page->index << PAGE_SHIFT;
end = start + PAGE_SIZE - 1;
min = min(min, start);
diff --git a/drivers/staging/fbtft/fbtft-core.c b/drivers/staging/fbtft/fbtft-core.c
index d4e14f7c9d57b9b2fc3bd28d4a535d77f2319183..e9662822e1efdc642649abef6f0ac70b19129653 100644
--- a/drivers/staging/fbtft/fbtft-core.c
+++ b/drivers/staging/fbtft/fbtft-core.c
@@ -326,7 +326,7 @@ static void fbtft_deferred_io(struct fb_info *info, struct list_head *pagelist)
{
struct fbtft_par *par = info->par;
unsigned int dirty_lines_start, dirty_lines_end;
- struct page *page;
+ struct fb_deferred_io_pageref *pageref;
unsigned long index;
unsigned int y_low = 0, y_high = 0;
int count = 0;
@@ -340,7 +340,8 @@ static void fbtft_deferred_io(struct fb_info *info, struct list_head *pagelist)
spin_unlock(&par->dirty_lock);
/* Mark display lines as dirty */
- list_for_each_entry(page, pagelist, lru) {
+ list_for_each_entry(pageref, pagelist, list) {
+ struct page *page = pageref->page;
count++;
index = page->index << PAGE_SHIFT;
y_low = index / info->fix.line_length;
diff --git a/drivers/video/fbdev/broadsheetfb.c b/drivers/video/fbdev/broadsheetfb.c
index 528bc0902338fab0b012f08ccc26fd03d91d7f4b..6afc6ef4cb5e0e859ef2a330dd70271714cdbf5e 100644
--- a/drivers/video/fbdev/broadsheetfb.c
+++ b/drivers/video/fbdev/broadsheetfb.c
@@ -934,7 +934,7 @@ static void broadsheetfb_dpy_deferred_io(struct fb_info *info,
{
u16 y1 = 0, h = 0;
int prev_index = -1;
- struct page *cur;
+ struct fb_deferred_io_pageref *pageref;
struct fb_deferred_io *fbdefio = info->fbdefio;
int h_inc;
u16 yres = info->var.yres;
@@ -944,7 +944,8 @@ static void broadsheetfb_dpy_deferred_io(struct fb_info *info,
h_inc = DIV_ROUND_UP(PAGE_SIZE , xres);
/* walk the written page list and swizzle the data */
- list_for_each_entry(cur, &fbdefio->pagelist, lru) {
+ list_for_each_entry(pageref, &fbdefio->pagelist, list) {
+ struct page *cur = pageref->page;
if (prev_index < 0) {
/* just starting so assign first page */
y1 = (cur->index << PAGE_SHIFT) / xres;
diff --git a/drivers/video/fbdev/core/fb_defio.c b/drivers/video/fbdev/core/fb_defio.c
index 6924d489a289e71c128c916e83bd35b3ae8139e2..1bdef5c241f7fc8dcf1cfde73f1bfcc0746b1e14 100644
--- a/drivers/video/fbdev/core/fb_defio.c
+++ b/drivers/video/fbdev/core/fb_defio.c
@@ -36,6 +36,60 @@ static struct page *fb_deferred_io_page(struct fb_info *info, unsigned long offs
return page;
}
+static struct fb_deferred_io_pageref *fb_deferred_io_pageref_get(struct fb_info *info,
+ unsigned long offset,
+ struct page *page)
+{
+ struct fb_deferred_io *fbdefio = info->fbdefio;
+ struct list_head *pos = &fbdefio->pagelist;
+ unsigned long pgoff = offset >> PAGE_SHIFT;
+ struct fb_deferred_io_pageref *pageref, *cur;
+
+ if (WARN_ON_ONCE(pgoff >= info->npagerefs))
+ return NULL; /* incorrect allocation size */
+
+ /* 1:1 mapping between pageref and page offset */
+ pageref = &info->pagerefs[pgoff];
+
+ /*
+ * This check is to catch the case where a new process could start
+ * writing to the same page through a new PTE. This new access
+ * can cause a call to .page_mkwrite even if the original process'
+ * PTE is marked writable.
+ */
+ if (!list_empty(&pageref->list))
+ goto pageref_already_added;
+
+ pageref->page = page;
+ pageref->offset = pgoff << PAGE_SHIFT;
+
+ if (unlikely(fbdefio->sort_pagelist)) {
+ /*
+ * We loop through the list of pagerefs before adding in
+ * order to keep the pagerefs sorted. This has significant
+ * overhead of O(n^2) with n being the number of written
+ * pages. If possible, drivers should try to work with
+ * unsorted page lists instead.
+ */
+ list_for_each_entry(cur, &info->fbdefio->pagelist, list) {
+ if (cur->offset > pageref->offset)
+ break;
+ }
+ pos = &cur->list;
+ }
+
+ list_add_tail(&pageref->list, pos);
+
+pageref_already_added:
+ return pageref;
+}
+
+static void fb_deferred_io_pageref_put(struct fb_deferred_io_pageref *pageref,
+ struct fb_info *info)
+{
+ list_del_init(&pageref->list);
+}
+
/* this is to find and return the vmalloc-ed fb pages */
static vm_fault_t fb_deferred_io_fault(struct vm_fault *vmf)
{
@@ -59,7 +113,7 @@ static vm_fault_t fb_deferred_io_fault(struct vm_fault *vmf)
printk(KERN_ERR "no mapping available\n");
BUG_ON(!page->mapping);
- page->index = vmf->pgoff;
+ page->index = vmf->pgoff; /* for page_mkclean() */
vmf->page = page;
return 0;
@@ -95,7 +149,11 @@ static vm_fault_t fb_deferred_io_mkwrite(struct vm_fault *vmf)
struct page *page = vmf->page;
struct fb_info *info = vmf->vma->vm_private_data;
struct fb_deferred_io *fbdefio = info->fbdefio;
- struct list_head *pos = &fbdefio->pagelist;
+ struct fb_deferred_io_pageref *pageref;
+ unsigned long offset;
+ vm_fault_t ret;
+
+ offset = (vmf->address - vmf->vma->vm_start);
/* this is a callback we get when userspace first tries to
write to the page. we schedule a workqueue. that workqueue
@@ -112,6 +170,12 @@ static vm_fault_t fb_deferred_io_mkwrite(struct vm_fault *vmf)
if (fbdefio->first_io && list_empty(&fbdefio->pagelist))
fbdefio->first_io(info);
+ pageref = fb_deferred_io_pageref_get(info, offset, page);
+ if (WARN_ON_ONCE(!pageref)) {
+ ret = VM_FAULT_OOM;
+ goto err_mutex_unlock;
+ }
+
/*
* We want the page to remain locked from ->page_mkwrite until
* the PTE is marked dirty to avoid page_mkclean() being called
@@ -120,47 +184,17 @@ static vm_fault_t fb_deferred_io_mkwrite(struct vm_fault *vmf)
* Do this by locking the page here and informing the caller
* about it with VM_FAULT_LOCKED.
*/
- lock_page(page);
-
- /*
- * This check is to catch the case where a new process could start
- * writing to the same page through a new PTE. This new access
- * can cause a call to .page_mkwrite even if the original process'
- * PTE is marked writable.
- *
- * TODO: The lru field is owned by the page cache; hence the name.
- * We dequeue in fb_deferred_io_work() after flushing the
- * page's content into video memory. Instead of lru, fbdefio
- * should have it's own field.
- */
- if (!list_empty(&page->lru))
- goto page_already_added;
-
- if (unlikely(fbdefio->sort_pagelist)) {
- /*
- * We loop through the pagelist before adding in order to
- * keep the pagelist sorted. This has significant overhead
- * of O(n^2) with n being the number of written pages. If
- * possible, drivers should try to work with unsorted page
- * lists instead.
- */
- struct page *cur;
-
- list_for_each_entry(cur, &fbdefio->pagelist, lru) {
- if (cur->index > page->index)
- break;
- }
- pos = &cur->lru;
- }
-
- list_add_tail(&page->lru, pos);
+ lock_page(pageref->page);
-page_already_added:
mutex_unlock(&fbdefio->lock);
/* come back after delay to process the deferred IO */
schedule_delayed_work(&info->deferred_work, fbdefio->delay);
return VM_FAULT_LOCKED;
+
+err_mutex_unlock:
+ mutex_unlock(&fbdefio->lock);
+ return ret;
}
static const struct vm_operations_struct fb_deferred_io_vm_ops = {
@@ -186,15 +220,14 @@ EXPORT_SYMBOL_GPL(fb_deferred_io_mmap);
/* workqueue callback */
static void fb_deferred_io_work(struct work_struct *work)
{
- struct fb_info *info = container_of(work, struct fb_info,
- deferred_work.work);
- struct list_head *node, *next;
- struct page *cur;
+ struct fb_info *info = container_of(work, struct fb_info, deferred_work.work);
+ struct fb_deferred_io_pageref *pageref, *next;
struct fb_deferred_io *fbdefio = info->fbdefio;
/* here we mkclean the pages, then do all deferred IO */
mutex_lock(&fbdefio->lock);
- list_for_each_entry(cur, &fbdefio->pagelist, lru) {
+ list_for_each_entry(pageref, &fbdefio->pagelist, list) {
+ struct page *cur = pageref->page;
lock_page(cur);
page_mkclean(cur);
unlock_page(cur);
@@ -204,30 +237,48 @@ static void fb_deferred_io_work(struct work_struct *work)
fbdefio->deferred_io(info, &fbdefio->pagelist);
/* clear the list */
- list_for_each_safe(node, next, &fbdefio->pagelist) {
- list_del_init(node);
- }
+ list_for_each_entry_safe(pageref, next, &fbdefio->pagelist, list)
+ fb_deferred_io_pageref_put(pageref, info);
+
mutex_unlock(&fbdefio->lock);
}
-void fb_deferred_io_init(struct fb_info *info)
+int fb_deferred_io_init(struct fb_info *info)
{
struct fb_deferred_io *fbdefio = info->fbdefio;
- struct page *page;
- unsigned int i;
+ struct fb_deferred_io_pageref *pagerefs;
+ unsigned long npagerefs, i;
+ int ret;
BUG_ON(!fbdefio);
+
+ if (WARN_ON(!info->fix.smem_len))
+ return -EINVAL;
+
mutex_init(&fbdefio->lock);
INIT_DELAYED_WORK(&info->deferred_work, fb_deferred_io_work);
INIT_LIST_HEAD(&fbdefio->pagelist);
if (fbdefio->delay == 0) /* set a default of 1 s */
fbdefio->delay = HZ;
- /* initialize all the page lists one time */
- for (i = 0; i < info->fix.smem_len; i += PAGE_SIZE) {
- page = fb_deferred_io_page(info, i);
- INIT_LIST_HEAD(&page->lru);
+ npagerefs = DIV_ROUND_UP(info->fix.smem_len, PAGE_SIZE);
+
+ /* alloc a page ref for each page of the display memory */
+ pagerefs = kvcalloc(npagerefs, sizeof(*pagerefs), GFP_KERNEL);
+ if (!pagerefs) {
+ ret = -ENOMEM;
+ goto err;
}
+ for (i = 0; i < npagerefs; ++i)
+ INIT_LIST_HEAD(&pagerefs[i].list);
+ info->npagerefs = npagerefs;
+ info->pagerefs = pagerefs;
+
+ return 0;
+
+err:
+ mutex_destroy(&fbdefio->lock);
+ return ret;
}
EXPORT_SYMBOL_GPL(fb_deferred_io_init);
@@ -254,6 +305,7 @@ void fb_deferred_io_cleanup(struct fb_info *info)
page->mapping = NULL;
}
+ kvfree(info->pagerefs);
mutex_destroy(&fbdefio->lock);
}
EXPORT_SYMBOL_GPL(fb_deferred_io_cleanup);
diff --git a/drivers/video/fbdev/hyperv_fb.c b/drivers/video/fbdev/hyperv_fb.c
index d7f6abf827b9d36326d7051a8e0c0635c607a29c..51eb57ea68f7f4d72fb5a43e7049413b2be3a855 100644
--- a/drivers/video/fbdev/hyperv_fb.c
+++ b/drivers/video/fbdev/hyperv_fb.c
@@ -424,7 +424,7 @@ static void synthvid_deferred_io(struct fb_info *p,
struct list_head *pagelist)
{
struct hvfb_par *par = p->par;
- struct page *page;
+ struct fb_deferred_io_pageref *pageref;
unsigned long start, end;
int y1, y2, miny, maxy;
@@ -437,7 +437,8 @@ static void synthvid_deferred_io(struct fb_info *p,
* in synthvid_update function by clamping the y2
* value to yres.
*/
- list_for_each_entry(page, pagelist, lru) {
+ list_for_each_entry(pageref, pagelist, list) {
+ struct page *page = pageref->page;
start = page->index << PAGE_SHIFT;
end = start + PAGE_SIZE - 1;
y1 = start / p->fix.line_length;
diff --git a/drivers/video/fbdev/metronomefb.c b/drivers/video/fbdev/metronomefb.c
index 2541f2fe065b84cc4598809c40b00b2f26b324f6..8352fa3f4cef235d42c86246a7722f6da1798687 100644
--- a/drivers/video/fbdev/metronomefb.c
+++ b/drivers/video/fbdev/metronomefb.c
@@ -469,12 +469,13 @@ static void metronomefb_dpy_deferred_io(struct fb_info *info,
struct list_head *pagelist)
{
u16 cksum;
- struct page *cur;
+ struct fb_deferred_io_pageref *pageref;
struct fb_deferred_io *fbdefio = info->fbdefio;
struct metronomefb_par *par = info->par;
/* walk the written page list and swizzle the data */
- list_for_each_entry(cur, &fbdefio->pagelist, lru) {
+ list_for_each_entry(pageref, &fbdefio->pagelist, list) {
+ struct page *cur = pageref->page;
cksum = metronomefb_dpy_update_page(par,
(cur->index << PAGE_SHIFT));
par->metromem_img_csum -= par->csum_table[cur->index];
diff --git a/drivers/video/fbdev/sh_mobile_lcdcfb.c b/drivers/video/fbdev/sh_mobile_lcdcfb.c
index ad034eb0e7a0c59888001773f36b5089637941c7..aea0660ba0c37b467caf0f40803e39e607f5c654 100644
--- a/drivers/video/fbdev/sh_mobile_lcdcfb.c
+++ b/drivers/video/fbdev/sh_mobile_lcdcfb.c
@@ -440,13 +440,15 @@ static int sh_mobile_lcdc_sginit(struct fb_info *info,
{
struct sh_mobile_lcdc_chan *ch = info->par;
unsigned int nr_pages_max = ch->fb_size >> PAGE_SHIFT;
- struct page *page;
+ struct fb_deferred_io_pageref *pageref;
int nr_pages = 0;
sg_init_table(ch->sglist, nr_pages_max);
- list_for_each_entry(page, pagelist, lru)
+ list_for_each_entry(pageref, pagelist, list) {
+ struct page *page = pageref->page;
sg_set_page(&ch->sglist[nr_pages++], page, PAGE_SIZE, 0);
+ }
return nr_pages;
}
diff --git a/drivers/video/fbdev/smscufx.c b/drivers/video/fbdev/smscufx.c
index 9383f8d0914c49ae3cc88f5fa87fe9a39d13bb00..eb108f56ea04c5423a455256d4d6154220256a75 100644
--- a/drivers/video/fbdev/smscufx.c
+++ b/drivers/video/fbdev/smscufx.c
@@ -958,7 +958,7 @@ static void ufx_ops_fillrect(struct fb_info *info,
static void ufx_dpy_deferred_io(struct fb_info *info,
struct list_head *pagelist)
{
- struct page *cur;
+ struct fb_deferred_io_pageref *pageref;
struct fb_deferred_io *fbdefio = info->fbdefio;
struct ufx_data *dev = info->par;
@@ -969,9 +969,10 @@ static void ufx_dpy_deferred_io(struct fb_info *info,
return;
/* walk the written page list and render each to device */
- list_for_each_entry(cur, &fbdefio->pagelist, lru) {
+ list_for_each_entry(pageref, &fbdefio->pagelist, list) {
/* create a rectangle of full screen width that encloses the
* entire dirty framebuffer page */
+ struct page *cur = pageref->page;
const int x = 0;
const int width = dev->info->var.xres;
const int y = (cur->index << PAGE_SHIFT) / (width * 2);
diff --git a/drivers/video/fbdev/udlfb.c b/drivers/video/fbdev/udlfb.c
index 179b30ba09f503f54cc5693e2d92e154feebc96d..f70b9cc8e85548e5344260312482416d10adb3ff 100644
--- a/drivers/video/fbdev/udlfb.c
+++ b/drivers/video/fbdev/udlfb.c
@@ -784,7 +784,7 @@ static void dlfb_ops_fillrect(struct fb_info *info,
static void dlfb_dpy_deferred_io(struct fb_info *info,
struct list_head *pagelist)
{
- struct page *cur;
+ struct fb_deferred_io_pageref *pageref;
struct fb_deferred_io *fbdefio = info->fbdefio;
struct dlfb_data *dlfb = info->par;
struct urb *urb;
@@ -811,7 +811,8 @@ static void dlfb_dpy_deferred_io(struct fb_info *info,
cmd = urb->transfer_buffer;
/* walk the written page list and render each to device */
- list_for_each_entry(cur, &fbdefio->pagelist, lru) {
+ list_for_each_entry(pageref, &fbdefio->pagelist, list) {
+ struct page *cur = pageref->page;
if (dlfb_render_hline(dlfb, &urb, (char *) info->fix.smem_start,
&cmd, cur->index << PAGE_SHIFT,
diff --git a/drivers/video/fbdev/xen-fbfront.c b/drivers/video/fbdev/xen-fbfront.c
index 6c8846eba2fb343d6bd142902aec6d2edec96e19..608fcde767d33df4ee4dbdc340b3f85de9dea817 100644
--- a/drivers/video/fbdev/xen-fbfront.c
+++ b/drivers/video/fbdev/xen-fbfront.c
@@ -185,13 +185,14 @@ static void xenfb_deferred_io(struct fb_info *fb_info,
struct list_head *pagelist)
{
struct xenfb_info *info = fb_info->par;
- struct page *page;
+ struct fb_deferred_io_pageref *pageref;
unsigned long beg, end;
int y1, y2, miny, maxy;
miny = INT_MAX;
maxy = 0;
- list_for_each_entry(page, pagelist, lru) {
+ list_for_each_entry(pageref, pagelist, list) {
+ struct page *page = pageref->page;
beg = page->index << PAGE_SHIFT;
end = beg + PAGE_SIZE - 1;
y1 = beg / fb_info->fix.line_length;
diff --git a/include/linux/fb.h b/include/linux/fb.h
index f95da1af9ff6a7858c928c164327213a2aa7b598..a332590c0fae9db49cd9bb44f2604b9978b0907f 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -201,6 +201,13 @@ struct fb_pixmap {
};
#ifdef CONFIG_FB_DEFERRED_IO
+struct fb_deferred_io_pageref {
+ struct page *page;
+ unsigned long offset;
+ /* private */
+ struct list_head list;
+};
+
struct fb_deferred_io {
/* delay between mkwrite and deferred handler */
unsigned long delay;
@@ -468,6 +475,8 @@ struct fb_info {
#endif
#ifdef CONFIG_FB_DEFERRED_IO
struct delayed_work deferred_work;
+ unsigned long npagerefs;
+ struct fb_deferred_io_pageref *pagerefs;
struct fb_deferred_io *fbdefio;
#endif
@@ -661,7 +670,7 @@ static inline void __fb_pad_aligned_buffer(u8 *dst, u32 d_pitch,
/* drivers/video/fb_defio.c */
int fb_deferred_io_mmap(struct fb_info *info, struct vm_area_struct *vma);
-extern void fb_deferred_io_init(struct fb_info *info);
+extern int fb_deferred_io_init(struct fb_info *info);
extern void fb_deferred_io_open(struct fb_info *info,
struct inode *inode,
struct file *file);