提交 ec7a3197 编写于 作者: N NeilBrown 提交者: Linus Torvalds

[PATCH] md/bitmap: cleaner separation of page attribute handlers in md/bitmap

md/bitmap has some attributes per-page.  Handling of these attributes in
largely abstracted in set_page_attr and clear_page_attr.  However
get_page_attr exposes the format used to store them.  So prior to changing
that format, introduce test_page_attr instead of get_page_attr, and make
appropriate usage changes.
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
上级 0b79ccf0
......@@ -717,9 +717,10 @@ static inline void clear_page_attr(struct bitmap *bitmap, struct page *page,
bitmap->filemap_attr[page->index] &= ~attr;
}
static inline unsigned long get_page_attr(struct bitmap *bitmap, struct page *page)
static inline unsigned long test_page_attr(struct bitmap *bitmap, struct page *page,
enum bitmap_page_attr attr)
{
return bitmap->filemap_attr[page->index];
return bitmap->filemap_attr[page->index] & attr;
}
/*
......@@ -745,7 +746,7 @@ static void bitmap_file_set_bit(struct bitmap *bitmap, sector_t block)
/* make sure the page stays cached until it gets written out */
if (! (get_page_attr(bitmap, page) & BITMAP_PAGE_DIRTY))
if (! test_page_attr(bitmap, page, BITMAP_PAGE_DIRTY))
get_page(page);
/* set the bit */
......@@ -769,7 +770,8 @@ static void bitmap_writeback(struct bitmap *bitmap);
* sync the dirty pages of the bitmap file to disk */
int bitmap_unplug(struct bitmap *bitmap)
{
unsigned long i, attr, flags;
unsigned long i, flags;
int dirty, need_write;
struct page *page;
int wait = 0;
int err;
......@@ -786,17 +788,18 @@ int bitmap_unplug(struct bitmap *bitmap)
return 0;
}
page = bitmap->filemap[i];
attr = get_page_attr(bitmap, page);
dirty = test_page_attr(bitmap, page, BITMAP_PAGE_DIRTY);
need_write = test_page_attr(bitmap, page, BITMAP_PAGE_NEEDWRITE);
clear_page_attr(bitmap, page, BITMAP_PAGE_DIRTY);
clear_page_attr(bitmap, page, BITMAP_PAGE_NEEDWRITE);
if ((attr & BITMAP_PAGE_DIRTY))
if (dirty)
wait = 1;
spin_unlock_irqrestore(&bitmap->lock, flags);
if (attr & (BITMAP_PAGE_DIRTY | BITMAP_PAGE_NEEDWRITE)) {
if (dirty | need_write) {
err = write_page(bitmap, page, 0);
if (err == -EAGAIN) {
if (attr & BITMAP_PAGE_DIRTY)
if (dirty)
err = write_page(bitmap, page, 1);
else
err = 0;
......@@ -961,12 +964,11 @@ void bitmap_write_all(struct bitmap *bitmap)
/* We don't actually write all bitmap blocks here,
* just flag them as needing to be written
*/
int i;
unsigned long chunks = bitmap->chunks;
unsigned long bytes = (chunks+7)/8 + sizeof(bitmap_super_t);
unsigned long num_pages = (bytes + PAGE_SIZE-1) / PAGE_SIZE;
while (num_pages--)
bitmap->filemap_attr[num_pages] |= BITMAP_PAGE_NEEDWRITE;
for (i=0; i < bitmap->file_pages; i++)
set_page_attr(bitmap, bitmap->filemap[i],
BITMAP_PAGE_NEEDWRITE);
}
......@@ -997,7 +999,6 @@ int bitmap_daemon_work(struct bitmap *bitmap)
struct page *page = NULL, *lastpage = NULL;
int err = 0;
int blocks;
int attr;
void *paddr;
if (bitmap == NULL)
......@@ -1019,13 +1020,15 @@ int bitmap_daemon_work(struct bitmap *bitmap)
if (page != lastpage) {
/* skip this page unless it's marked as needing cleaning */
if (!((attr=get_page_attr(bitmap, page)) & BITMAP_PAGE_CLEAN)) {
if (attr & BITMAP_PAGE_NEEDWRITE) {
if (!test_page_attr(bitmap, page, BITMAP_PAGE_CLEAN)) {
int need_write = test_page_attr(bitmap, page,
BITMAP_PAGE_NEEDWRITE);
if (need_write) {
get_page(page);
clear_page_attr(bitmap, page, BITMAP_PAGE_NEEDWRITE);
}
spin_unlock_irqrestore(&bitmap->lock, flags);
if (attr & BITMAP_PAGE_NEEDWRITE) {
if (need_write) {
switch (write_page(bitmap, page, 0)) {
case -EAGAIN:
set_page_attr(bitmap, page, BITMAP_PAGE_NEEDWRITE);
......@@ -1043,7 +1046,7 @@ int bitmap_daemon_work(struct bitmap *bitmap)
/* grab the new page, sync and release the old */
get_page(page);
if (lastpage != NULL) {
if (get_page_attr(bitmap, lastpage) & BITMAP_PAGE_NEEDWRITE) {
if (test_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE)) {
clear_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE);
spin_unlock_irqrestore(&bitmap->lock, flags);
err = write_page(bitmap, lastpage, 0);
......@@ -1097,7 +1100,7 @@ int bitmap_daemon_work(struct bitmap *bitmap)
/* now sync the final page */
if (lastpage != NULL) {
spin_lock_irqsave(&bitmap->lock, flags);
if (get_page_attr(bitmap, lastpage) &BITMAP_PAGE_NEEDWRITE) {
if (test_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE)) {
clear_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE);
spin_unlock_irqrestore(&bitmap->lock, flags);
err = write_page(bitmap, lastpage, 0);
......
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