X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=mm%2Ffilemap.c;h=54e9686508550b198b4779df048bbfe46b2ddb08;hb=b42f931737bea8ca3982449d63ec46410d13e891;hp=feb8448d8618795238a9cbbc5975f8950b2c5e23;hpb=a60637c85893e7191faaafa6a72e197c24386727;p=linux-2.6

diff --git a/mm/filemap.c b/mm/filemap.c
index feb8448d86..54e9686508 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -109,7 +109,7 @@
 /*
  * Remove a page from the page cache and free it. Caller has to make
  * sure the page is locked and that nobody else uses it - or that usage
- * is safe.  The caller must hold a write_lock on the mapping's tree_lock.
+ * is safe.  The caller must hold the mapping's tree_lock.
  */
 void __remove_from_page_cache(struct page *page)
 {
@@ -141,9 +141,9 @@ void remove_from_page_cache(struct page *page)
 
 	BUG_ON(!PageLocked(page));
 
-	write_lock_irq(&mapping->tree_lock);
+	spin_lock_irq(&mapping->tree_lock);
 	__remove_from_page_cache(page);
-	write_unlock_irq(&mapping->tree_lock);
+	spin_unlock_irq(&mapping->tree_lock);
 }
 
 static int sync_page(void *word)
@@ -469,7 +469,7 @@ int add_to_page_cache_locked(struct page *page, struct address_space *mapping,
 		page->mapping = mapping;
 		page->index = offset;
 
-		write_lock_irq(&mapping->tree_lock);
+		spin_lock_irq(&mapping->tree_lock);
 		error = radix_tree_insert(&mapping->page_tree, offset, page);
 		if (likely(!error)) {
 			mapping->nrpages++;
@@ -480,7 +480,7 @@ int add_to_page_cache_locked(struct page *page, struct address_space *mapping,
 			page_cache_release(page);
 		}
 
-		write_unlock_irq(&mapping->tree_lock);
+		spin_unlock_irq(&mapping->tree_lock);
 		radix_tree_preload_end();
 	} else
 		mem_cgroup_uncharge_cache_page(page);
@@ -558,14 +558,14 @@ EXPORT_SYMBOL(wait_on_page_bit);
  * But that's OK - sleepers in wait_on_page_writeback() just go back to sleep.
  *
  * The first mb is necessary to safely close the critical section opened by the
- * TestSetPageLocked(), the second mb is necessary to enforce ordering between
- * the clear_bit and the read of the waitqueue (to avoid SMP races with a
- * parallel wait_on_page_locked()).
+ * test_and_set_bit() to lock the page; the second mb is necessary to enforce
+ * ordering between the clear_bit and the read of the waitqueue (to avoid SMP
+ * races with a parallel wait_on_page_locked()).
  */
 void unlock_page(struct page *page)
 {
 	smp_mb__before_clear_bit();
-	if (!TestClearPageLocked(page))
+	if (!test_and_clear_bit(PG_locked, &page->flags))
 		BUG();
 	smp_mb__after_clear_bit(); 
 	wake_up_page(page, PG_locked);
@@ -931,7 +931,7 @@ grab_cache_page_nowait(struct address_space *mapping, pgoff_t index)
 	struct page *page = find_get_page(mapping, index);
 
 	if (page) {
-		if (!TestSetPageLocked(page))
+		if (trylock_page(page))
 			return page;
 		page_cache_release(page);
 		return NULL;
@@ -1023,8 +1023,17 @@ find_page:
 					ra, filp, page,
 					index, last_index - index);
 		}
-		if (!PageUptodate(page))
-			goto page_not_up_to_date;
+		if (!PageUptodate(page)) {
+			if (inode->i_blkbits == PAGE_CACHE_SHIFT ||
+					!mapping->a_ops->is_partially_uptodate)
+				goto page_not_up_to_date;
+			if (!trylock_page(page))
+				goto page_not_up_to_date;
+			if (!mapping->a_ops->is_partially_uptodate(page,
+								desc, offset))
+				goto page_not_up_to_date_locked;
+			unlock_page(page);
+		}
 page_ok:
 		/*
 		 * i_size must be checked after we know the page is Uptodate.
@@ -1094,6 +1103,7 @@ page_not_up_to_date:
 		if (lock_page_killable(page))
 			goto readpage_eio;
 
+page_not_up_to_date_locked:
 		/* Did it get truncated before we got the lock? */
 		if (!page->mapping) {
 			unlock_page(page);
@@ -1758,8 +1768,9 @@ static int __remove_suid(struct dentry *dentry, int kill)
 	return notify_change(dentry, &newattrs);
 }
 
-int remove_suid(struct dentry *dentry)
+int file_remove_suid(struct file *file)
 {
+	struct dentry *dentry = file->f_path.dentry;
 	int killsuid = should_remove_suid(dentry);
 	int killpriv = security_inode_need_killpriv(dentry);
 	int error = 0;
@@ -1773,7 +1784,7 @@ int remove_suid(struct dentry *dentry)
 
 	return error;
 }
-EXPORT_SYMBOL(remove_suid);
+EXPORT_SYMBOL(file_remove_suid);
 
 static size_t __iovec_copy_from_user_inatomic(char *vaddr,
 			const struct iovec *iov, size_t base, size_t bytes)
@@ -1868,7 +1879,7 @@ void iov_iter_advance(struct iov_iter *i, size_t bytes)
 		 * The !iov->iov_len check ensures we skip over unlikely
 		 * zero-length segments (without overruning the iovec).
 		 */
-		while (bytes || unlikely(!iov->iov_len && i->count)) {
+		while (bytes || unlikely(i->count && !iov->iov_len)) {
 			int copy;
 
 			copy = min(bytes, iov->iov_len - base);
@@ -2529,7 +2540,7 @@ __generic_file_aio_write_nolock(struct kiocb *iocb, const struct iovec *iov,
 	if (count == 0)
 		goto out;
 
-	err = remove_suid(file->f_path.dentry);
+	err = file_remove_suid(file);
 	if (err)
 		goto out;