mapping->nrpages--;
__dec_zone_page_state(page, NR_FILE_PAGES);
BUG_ON(page_mapped(page));
- mem_cgroup_uncharge_cache_page(page);
/*
* Some filesystems seem to re-dirty the page even after
spin_lock_irq(&mapping->tree_lock);
__remove_from_page_cache(page);
spin_unlock_irq(&mapping->tree_lock);
+ mem_cgroup_uncharge_cache_page(page);
}
static int sync_page(void *word)
}
return err;
}
+EXPORT_SYMBOL(filemap_write_and_wait_range);
/**
* add_to_page_cache_locked - add a locked page to the pagecache
if (likely(!error)) {
mapping->nrpages++;
__inc_zone_page_state(page, NR_FILE_PAGES);
+ spin_unlock_irq(&mapping->tree_lock);
} else {
page->mapping = NULL;
+ spin_unlock_irq(&mapping->tree_lock);
mem_cgroup_uncharge_cache_page(page);
page_cache_release(page);
}
-
- spin_unlock_irq(&mapping->tree_lock);
radix_tree_preload_end();
} else
mem_cgroup_uncharge_cache_page(page);
}
return ret;
}
+EXPORT_SYMBOL_GPL(add_to_page_cache_lru);
#ifdef CONFIG_NUMA
struct page *__page_cache_alloc(gfp_t gfp)
EXPORT_SYMBOL(wait_on_page_bit);
/**
+ * add_page_wait_queue - Add an arbitrary waiter to a page's wait queue
+ * @page: Page defining the wait queue of interest
+ * @waiter: Waiter to add to the queue
+ *
+ * Add an arbitrary @waiter to the wait queue for the nominated @page.
+ */
+void add_page_wait_queue(struct page *page, wait_queue_t *waiter)
+{
+ wait_queue_head_t *q = page_waitqueue(page);
+ unsigned long flags;
+
+ spin_lock_irqsave(&q->lock, flags);
+ __add_wait_queue(q, waiter);
+ spin_unlock_irqrestore(&q->lock, flags);
+}
+EXPORT_SYMBOL_GPL(add_page_wait_queue);
+
+/**
* unlock_page - unlock a locked page
* @page: the page
*
return __wait_on_bit_lock(page_waitqueue(page), &wait,
sync_page_killable, TASK_KILLABLE);
}
+EXPORT_SYMBOL_GPL(__lock_page_killable);
/**
* __lock_page_nosync - get a lock on the page, without calling sync_page()
static void shrink_readahead_size_eio(struct file *filp,
struct file_ra_state *ra)
{
- if (!ra->ra_pages)
- return;
-
ra->ra_pages /= 4;
}
if (!mapping || !mapping->a_ops || !mapping->a_ops->readpage)
return -EINVAL;
- force_page_cache_readahead(mapping, filp, index,
- max_sane_readahead(nr));
+ force_page_cache_readahead(mapping, filp, index, nr);
return 0;
}
#define MMAP_LOTSAMISS (100)
+/*
+ * Synchronous readahead happens when we don't even find
+ * a page in the page cache at all.
+ */
+static void do_sync_mmap_readahead(struct vm_area_struct *vma,
+ struct file_ra_state *ra,
+ struct file *file,
+ pgoff_t offset)
+{
+ unsigned long ra_pages;
+ struct address_space *mapping = file->f_mapping;
+
+ /* If we don't want any read-ahead, don't bother */
+ if (VM_RandomReadHint(vma))
+ return;
+
+ if (VM_SequentialReadHint(vma) ||
+ offset - 1 == (ra->prev_pos >> PAGE_CACHE_SHIFT)) {
+ page_cache_sync_readahead(mapping, ra, file, offset, 1);
+ return;
+ }
+
+ if (ra->mmap_miss < INT_MAX)
+ ra->mmap_miss++;
+
+ /*
+ * Do we miss much more than hit in this file? If so,
+ * stop bothering with read-ahead. It will only hurt.
+ */
+ if (ra->mmap_miss > MMAP_LOTSAMISS)
+ return;
+
+ /*
+ * mmap read-around
+ */
+ ra_pages = max_sane_readahead(ra->ra_pages);
+ if (ra_pages) {
+ ra->start = max_t(long, 0, offset - ra_pages/2);
+ ra->size = ra_pages;
+ ra->async_size = 0;
+ ra_submit(ra, mapping, file);
+ }
+}
+
+/*
+ * Asynchronous readahead happens when we find the page and PG_readahead,
+ * so we want to possibly extend the readahead further..
+ */
+static void do_async_mmap_readahead(struct vm_area_struct *vma,
+ struct file_ra_state *ra,
+ struct file *file,
+ struct page *page,
+ pgoff_t offset)
+{
+ struct address_space *mapping = file->f_mapping;
+
+ /* If we don't want any read-ahead, don't bother */
+ if (VM_RandomReadHint(vma))
+ return;
+ if (ra->mmap_miss > 0)
+ ra->mmap_miss--;
+ if (PageReadahead(page))
+ page_cache_async_readahead(mapping, ra, file,
+ page, offset, ra->ra_pages);
+}
+
/**
* filemap_fault - read in file data for page fault handling
* @vma: vma in which the fault was taken
struct address_space *mapping = file->f_mapping;
struct file_ra_state *ra = &file->f_ra;
struct inode *inode = mapping->host;
+ pgoff_t offset = vmf->pgoff;
struct page *page;
pgoff_t size;
- int did_readaround = 0;
int ret = 0;
size = (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
- if (vmf->pgoff >= size)
+ if (offset >= size)
return VM_FAULT_SIGBUS;
- /* If we don't want any read-ahead, don't bother */
- if (VM_RandomReadHint(vma))
- goto no_cached_page;
-
/*
* Do we have something in the page cache already?
*/
-retry_find:
- page = find_lock_page(mapping, vmf->pgoff);
- /*
- * For sequential accesses, we use the generic readahead logic.
- */
- if (VM_SequentialReadHint(vma)) {
- if (!page) {
- page_cache_sync_readahead(mapping, ra, file,
- vmf->pgoff, 1);
- page = find_lock_page(mapping, vmf->pgoff);
- if (!page)
- goto no_cached_page;
- }
- if (PageReadahead(page)) {
- page_cache_async_readahead(mapping, ra, file, page,
- vmf->pgoff, 1);
- }
- }
-
- if (!page) {
- unsigned long ra_pages;
-
- ra->mmap_miss++;
-
+ page = find_get_page(mapping, offset);
+ if (likely(page)) {
/*
- * Do we miss much more than hit in this file? If so,
- * stop bothering with read-ahead. It will only hurt.
+ * We found the page, so try async readahead before
+ * waiting for the lock.
*/
- if (ra->mmap_miss > MMAP_LOTSAMISS)
- goto no_cached_page;
+ do_async_mmap_readahead(vma, ra, file, page, offset);
+ lock_page(page);
- /*
- * To keep the pgmajfault counter straight, we need to
- * check did_readaround, as this is an inner loop.
- */
- if (!did_readaround) {
- ret = VM_FAULT_MAJOR;
- count_vm_event(PGMAJFAULT);
- }
- did_readaround = 1;
- ra_pages = max_sane_readahead(file->f_ra.ra_pages);
- if (ra_pages) {
- pgoff_t start = 0;
-
- if (vmf->pgoff > ra_pages / 2)
- start = vmf->pgoff - ra_pages / 2;
- do_page_cache_readahead(mapping, file, start, ra_pages);
+ /* Did it get truncated? */
+ if (unlikely(page->mapping != mapping)) {
+ unlock_page(page);
+ put_page(page);
+ goto no_cached_page;
}
- page = find_lock_page(mapping, vmf->pgoff);
+ } else {
+ /* No page in the page cache at all */
+ do_sync_mmap_readahead(vma, ra, file, offset);
+ count_vm_event(PGMAJFAULT);
+ ret = VM_FAULT_MAJOR;
+retry_find:
+ page = find_lock_page(mapping, offset);
if (!page)
goto no_cached_page;
}
- if (!did_readaround)
- ra->mmap_miss--;
-
/*
* We have a locked page in the page cache, now we need to check
* that it's up-to-date. If not, it is going to be due to an error.
if (unlikely(!PageUptodate(page)))
goto page_not_uptodate;
- /* Must recheck i_size under page lock */
+ /*
+ * Found the page and have a reference on it.
+ * We must recheck i_size under page lock.
+ */
size = (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
- if (unlikely(vmf->pgoff >= size)) {
+ if (unlikely(offset >= size)) {
unlock_page(page);
page_cache_release(page);
return VM_FAULT_SIGBUS;
}
- /*
- * Found the page and have a reference on it.
- */
- ra->prev_pos = (loff_t)page->index << PAGE_CACHE_SHIFT;
+ ra->prev_pos = (loff_t)offset << PAGE_CACHE_SHIFT;
vmf->page = page;
return ret | VM_FAULT_LOCKED;
* We're only likely to ever get here if MADV_RANDOM is in
* effect.
*/
- error = page_cache_read(file, vmf->pgoff);
+ error = page_cache_read(file, offset);
/*
* The page we want has now been added to the page cache.
return VM_FAULT_SIGBUS;
page_not_uptodate:
- /* IO error path */
- if (!did_readaround) {
- ret = VM_FAULT_MAJOR;
- count_vm_event(PGMAJFAULT);
- }
-
/*
* Umm, take care of errors if the page isn't up-to-date.
* Try to re-read it _once_. We do this synchronously,
static size_t __iovec_copy_from_user_inatomic(char *vaddr,
const struct iovec *iov, size_t base, size_t bytes)
{
- size_t copied = 0, left = 0, total = bytes;
+ size_t copied = 0, left = 0;
while (bytes) {
char __user *buf = iov->iov_base + base;
int copy = min(bytes, iov->iov_len - base);
base = 0;
- left = __copy_from_user_inatomic_nocache(vaddr, buf, copy, total);
+ left = __copy_from_user_inatomic(vaddr, buf, copy);
copied += copy;
bytes -= copy;
vaddr += copy;
if (likely(i->nr_segs == 1)) {
int left;
char __user *buf = i->iov->iov_base + i->iov_offset;
-
- left = __copy_from_user_inatomic_nocache(kaddr + offset,
- buf, bytes, bytes);
+ left = __copy_from_user_inatomic(kaddr + offset, buf, bytes);
copied = bytes - left;
} else {
copied = __iovec_copy_from_user_inatomic(kaddr + offset,
if (likely(i->nr_segs == 1)) {
int left;
char __user *buf = i->iov->iov_base + i->iov_offset;
-
- left = __copy_from_user_nocache(kaddr + offset, buf, bytes, bytes);
+ left = __copy_from_user(kaddr + offset, buf, bytes);
copied = bytes - left;
} else {
copied = __iovec_copy_from_user_inatomic(kaddr + offset,
* (presumably at page->private). If the release was successful, return `1'.
* Otherwise return zero.
*
+ * This may also be called if PG_fscache is set on a page, indicating that the
+ * page is known to the local caching routines.
+ *
* The @gfp_mask argument specifies whether I/O may be performed to release
* this page (__GFP_IO), and whether the call may block (__GFP_WAIT & __GFP_FS).
*
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff