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-rw-r--r--fs/squashfs/file_direct.c176
1 files changed, 0 insertions, 176 deletions
diff --git a/fs/squashfs/file_direct.c b/fs/squashfs/file_direct.c
deleted file mode 100644
index 62a0de6..0000000
--- a/fs/squashfs/file_direct.c
+++ /dev/null
@@ -1,176 +0,0 @@
-/*
- * Copyright (c) 2013
- * Phillip Lougher <phillip@squashfs.org.uk>
- *
- * This work is licensed under the terms of the GNU GPL, version 2. See
- * the COPYING file in the top-level directory.
- */
-
-#include <linux/fs.h>
-#include <linux/vfs.h>
-#include <linux/kernel.h>
-#include <linux/slab.h>
-#include <linux/string.h>
-#include <linux/pagemap.h>
-#include <linux/mutex.h>
-
-#include "squashfs_fs.h"
-#include "squashfs_fs_sb.h"
-#include "squashfs_fs_i.h"
-#include "squashfs.h"
-#include "page_actor.h"
-
-static int squashfs_read_cache(struct page *target_page, u64 block, int bsize,
- int pages, struct page **page);
-
-/* Read separately compressed datablock directly into page cache */
-int squashfs_readpage_block(struct page *target_page, u64 block, int bsize)
-
-{
- struct inode *inode = target_page->mapping->host;
- struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info;
-
- int file_end = (i_size_read(inode) - 1) >> PAGE_CACHE_SHIFT;
- int mask = (1 << (msblk->block_log - PAGE_CACHE_SHIFT)) - 1;
- int start_index = target_page->index & ~mask;
- int end_index = start_index | mask;
- int i, n, pages, missing_pages, bytes, res = -ENOMEM;
- struct page **page;
- struct squashfs_page_actor *actor;
- void *pageaddr;
-
- if (end_index > file_end)
- end_index = file_end;
-
- pages = end_index - start_index + 1;
-
- page = kmalloc(sizeof(void *) * pages, GFP_KERNEL);
- if (page == NULL)
- return res;
-
- /*
- * Create a "page actor" which will kmap and kunmap the
- * page cache pages appropriately within the decompressor
- */
- actor = squashfs_page_actor_init_special(page, pages, 0);
- if (actor == NULL)
- goto out;
-
- /* Try to grab all the pages covered by the Squashfs block */
- for (missing_pages = 0, i = 0, n = start_index; i < pages; i++, n++) {
- page[i] = (n == target_page->index) ? target_page :
- grab_cache_page_nowait(target_page->mapping, n);
-
- if (page[i] == NULL) {
- missing_pages++;
- continue;
- }
-
- if (PageUptodate(page[i])) {
- unlock_page(page[i]);
- page_cache_release(page[i]);
- page[i] = NULL;
- missing_pages++;
- }
- }
-
- if (missing_pages) {
- /*
- * Couldn't get one or more pages, this page has either
- * been VM reclaimed, but others are still in the page cache
- * and uptodate, or we're racing with another thread in
- * squashfs_readpage also trying to grab them. Fall back to
- * using an intermediate buffer.
- */
- res = squashfs_read_cache(target_page, block, bsize, pages,
- page);
- if (res < 0)
- goto mark_errored;
-
- goto out;
- }
-
- /* Decompress directly into the page cache buffers */
- res = squashfs_read_data(inode->i_sb, block, bsize, NULL, actor);
- if (res < 0)
- goto mark_errored;
-
- /* Last page may have trailing bytes not filled */
- bytes = res % PAGE_CACHE_SIZE;
- if (bytes) {
- pageaddr = kmap_atomic(page[pages - 1]);
- memset(pageaddr + bytes, 0, PAGE_CACHE_SIZE - bytes);
- kunmap_atomic(pageaddr);
- }
-
- /* Mark pages as uptodate, unlock and release */
- for (i = 0; i < pages; i++) {
- flush_dcache_page(page[i]);
- SetPageUptodate(page[i]);
- unlock_page(page[i]);
- if (page[i] != target_page)
- page_cache_release(page[i]);
- }
-
- kfree(actor);
- kfree(page);
-
- return 0;
-
-mark_errored:
- /* Decompression failed, mark pages as errored. Target_page is
- * dealt with by the caller
- */
- for (i = 0; i < pages; i++) {
- if (page[i] == NULL || page[i] == target_page)
- continue;
- flush_dcache_page(page[i]);
- SetPageError(page[i]);
- unlock_page(page[i]);
- page_cache_release(page[i]);
- }
-
-out:
- kfree(actor);
- kfree(page);
- return res;
-}
-
-
-static int squashfs_read_cache(struct page *target_page, u64 block, int bsize,
- int pages, struct page **page)
-{
- struct inode *i = target_page->mapping->host;
- struct squashfs_cache_entry *buffer = squashfs_get_datablock(i->i_sb,
- block, bsize);
- int bytes = buffer->length, res = buffer->error, n, offset = 0;
- void *pageaddr;
-
- if (res) {
- ERROR("Unable to read page, block %llx, size %x\n", block,
- bsize);
- goto out;
- }
-
- for (n = 0; n < pages && bytes > 0; n++,
- bytes -= PAGE_CACHE_SIZE, offset += PAGE_CACHE_SIZE) {
- int avail = min_t(int, bytes, PAGE_CACHE_SIZE);
-
- if (page[n] == NULL)
- continue;
-
- pageaddr = kmap_atomic(page[n]);
- squashfs_copy_data(pageaddr, buffer, offset, avail);
- memset(pageaddr + avail, 0, PAGE_CACHE_SIZE - avail);
- kunmap_atomic(pageaddr);
- flush_dcache_page(page[n]);
- SetPageUptodate(page[n]);
- unlock_page(page[n]);
- if (page[n] != target_page)
- page_cache_release(page[n]);
- }
-
-out:
- squashfs_cache_put(buffer);
- return res;
-}