Merge master.kernel.org:/home/rmk/linux-2.6-mmc

[sfrench/cifs-2.6.git] / mm / filemap.c

diff --git a/mm/filemap.c b/mm/filemap.c
index 036599d1177e3e8098f874e79785d538e3085e9a..4ef24a397684f7b9a51c70e94843f4cff35ed281 100644 (file)
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -134,7 +134,7 @@ static int sync_page(void *word)
        struct address_space *mapping;
        struct page *page;
 
-       page = container_of((page_flags_t *)word, struct page, flags);
+       page = container_of((unsigned long *)word, struct page, flags);
 
        /*
         * page_mapping() is being called without PG_locked held.
@@ -555,11 +555,12 @@ repeat:
                page_cache_get(page);
                if (TestSetPageLocked(page)) {
                        read_unlock_irq(&mapping->tree_lock);
-                       lock_page(page);
+                       __lock_page(page);
                        read_lock_irq(&mapping->tree_lock);
 
                        /* Has the page been truncated while we slept? */
-                       if (page->mapping != mapping || page->index != offset) {
+                       if (unlikely(page->mapping != mapping ||
+                                    page->index != offset)) {
                                unlock_page(page);
                                page_cache_release(page);
                                goto repeat;
@@ -831,8 +832,13 @@ readpage:
                /* Start the actual read. The read will unlock the page. */
                error = mapping->a_ops->readpage(filp, page);
 
-               if (unlikely(error))
+               if (unlikely(error)) {
+                       if (error == AOP_TRUNCATED_PAGE) {
+                               page_cache_release(page);
+                               goto find_page;
+                       }
                        goto readpage_error;
+               }
 
                if (!PageUptodate(page)) {
                        lock_page(page);
@@ -1030,8 +1036,8 @@ __generic_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
                        desc.error = 0;
                        do_generic_file_read(filp,ppos,&desc,file_read_actor);
                        retval += desc.written;
-                       if (!retval) {
-                               retval = desc.error;
+                       if (desc.error) {
+                               retval = retval ?: desc.error;
                                break;
                        }
                }
@@ -1152,26 +1158,24 @@ static int fastcall page_cache_read(struct file * file, unsigned long offset)
 {
        struct address_space *mapping = file->f_mapping;
        struct page *page; 
-       int error;
+       int ret;
 
-       page = page_cache_alloc_cold(mapping);
-       if (!page)
-               return -ENOMEM;
+       do {
+               page = page_cache_alloc_cold(mapping);
+               if (!page)
+                       return -ENOMEM;
+
+               ret = add_to_page_cache_lru(page, mapping, offset, GFP_KERNEL);
+               if (ret == 0)
+                       ret = mapping->a_ops->readpage(file, page);
+               else if (ret == -EEXIST)
+                       ret = 0; /* losing race to add is OK */
 
-       error = add_to_page_cache_lru(page, mapping, offset, GFP_KERNEL);
-       if (!error) {
-               error = mapping->a_ops->readpage(file, page);
                page_cache_release(page);
-               return error;
-       }
 
-       /*
-        * We arrive here in the unlikely event that someone 
-        * raced with us and added our page to the cache first
-        * or we are out of memory for radix-tree nodes.
-        */
-       page_cache_release(page);
-       return error == -EEXIST ? 0 : error;
+       } while (ret == AOP_TRUNCATED_PAGE);
+               
+       return ret;
 }
 
 #define MMAP_LOTSAMISS  (100)
@@ -1331,10 +1335,14 @@ page_not_uptodate:
                goto success;
        }
 
-       if (!mapping->a_ops->readpage(file, page)) {
+       error = mapping->a_ops->readpage(file, page);
+       if (!error) {
                wait_on_page_locked(page);
                if (PageUptodate(page))
                        goto success;
+       } else if (error == AOP_TRUNCATED_PAGE) {
+               page_cache_release(page);
+               goto retry_find;
        }
 
        /*
@@ -1358,10 +1366,14 @@ page_not_uptodate:
                goto success;
        }
        ClearPageError(page);
-       if (!mapping->a_ops->readpage(file, page)) {
+       error = mapping->a_ops->readpage(file, page);
+       if (!error) {
                wait_on_page_locked(page);
                if (PageUptodate(page))
                        goto success;
+       } else if (error == AOP_TRUNCATED_PAGE) {
+               page_cache_release(page);
+               goto retry_find;
        }
 
        /*
@@ -1444,10 +1456,14 @@ page_not_uptodate:
                goto success;
        }
 
-       if (!mapping->a_ops->readpage(file, page)) {
+       error = mapping->a_ops->readpage(file, page);
+       if (!error) {
                wait_on_page_locked(page);
                if (PageUptodate(page))
                        goto success;
+       } else if (error == AOP_TRUNCATED_PAGE) {
+               page_cache_release(page);
+               goto retry_find;
        }
 
        /*
@@ -1470,10 +1486,14 @@ page_not_uptodate:
        }
 
        ClearPageError(page);
-       if (!mapping->a_ops->readpage(file, page)) {
+       error = mapping->a_ops->readpage(file, page);
+       if (!error) {
                wait_on_page_locked(page);
                if (PageUptodate(page))
                        goto success;
+       } else if (error == AOP_TRUNCATED_PAGE) {
+               page_cache_release(page);
+               goto retry_find;
        }
 
        /*
@@ -1537,6 +1557,7 @@ repeat:
 
        return 0;
 }
+EXPORT_SYMBOL(filemap_populate);
 
 struct vm_operations_struct generic_file_vm_ops = {
        .nopage         = filemap_nopage,
@@ -1555,7 +1576,6 @@ int generic_file_mmap(struct file * file, struct vm_area_struct * vma)
        vma->vm_ops = &generic_file_vm_ops;
        return 0;
 }
-EXPORT_SYMBOL(filemap_populate);
 
 /*
  * This is for filesystems which do not implement ->writepage.
@@ -1934,12 +1954,16 @@ generic_file_buffered_write(struct kiocb *iocb, const struct iovec *iov,
                status = a_ops->prepare_write(file, page, offset, offset+bytes);
                if (unlikely(status)) {
                        loff_t isize = i_size_read(inode);
+
+                       if (status != AOP_TRUNCATED_PAGE)
+                               unlock_page(page);
+                       page_cache_release(page);
+                       if (status == AOP_TRUNCATED_PAGE)
+                               continue;
                        /*
                         * prepare_write() may have instantiated a few blocks
                         * outside i_size.  Trim these off again.
                         */
-                       unlock_page(page);
-                       page_cache_release(page);
                        if (pos + bytes > isize)
                                vmtruncate(inode, isize);
                        break;
@@ -1952,6 +1976,10 @@ generic_file_buffered_write(struct kiocb *iocb, const struct iovec *iov,
                                                cur_iov, iov_base, bytes);
                flush_dcache_page(page);
                status = a_ops->commit_write(file, page, offset, offset+bytes);
+               if (status == AOP_TRUNCATED_PAGE) {
+                       page_cache_release(page);
+                       continue;
+               }
                if (likely(copied > 0)) {
                        if (!status)
                                status = copied;