media: video: tegra: sh532u: fix out-of-bounds read
[linux-2.6.git] / mm / readahead.c
index aa1aa23..867f9dd 100644 (file)
@@ -9,6 +9,7 @@
 
 #include <linux/kernel.h>
 #include <linux/fs.h>
+#include <linux/gfp.h>
 #include <linux/mm.h>
 #include <linux/module.h>
 #include <linux/blkdev.h>
@@ -108,9 +109,12 @@ EXPORT_SYMBOL(read_cache_pages);
 static int read_pages(struct address_space *mapping, struct file *filp,
                struct list_head *pages, unsigned nr_pages)
 {
+       struct blk_plug plug;
        unsigned page_idx;
        int ret;
 
+       blk_start_plug(&plug);
+
        if (mapping->a_ops->readpages) {
                ret = mapping->a_ops->readpages(filp, mapping, pages, nr_pages);
                /* Clean up the remaining pages */
@@ -128,7 +132,10 @@ static int read_pages(struct address_space *mapping, struct file *filp,
                page_cache_release(page);
        }
        ret = 0;
+
 out:
+       blk_finish_plug(&plug);
+
        return ret;
 }
 
@@ -173,7 +180,7 @@ __do_page_cache_readahead(struct address_space *mapping, struct file *filp,
                if (page)
                        continue;
 
-               page = page_cache_alloc_cold(mapping);
+               page = page_cache_alloc_readahead(mapping);
                if (!page)
                        break;
                page->index = page_offset;
@@ -501,6 +508,12 @@ void page_cache_sync_readahead(struct address_space *mapping,
        if (!ra->ra_pages)
                return;
 
+       /* be dumb */
+       if (filp && (filp->f_mode & FMODE_RANDOM)) {
+               force_page_cache_readahead(mapping, filp, offset, req_size);
+               return;
+       }
+
        /* do read-ahead */
        ondemand_readahead(mapping, ra, filp, false, offset, req_size);
 }
@@ -516,7 +529,7 @@ EXPORT_SYMBOL_GPL(page_cache_sync_readahead);
  * @req_size: hint: total size of the read which the caller is performing in
  *            pagecache pages
  *
- * page_cache_async_ondemand() should be called when a page is used which
+ * page_cache_async_readahead() should be called when a page is used which
  * has the PG_readahead flag; this is a marker to suggest that the application
  * has used up enough of the readahead window that we should start pulling in
  * more pages.