fs/squashfs/file_cache.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2013
   4  * Phillip Lougher <phillip@squashfs.org.uk>
   5  */
   6
   7 #include <linux/fs.h>
   8 #include <linux/vfs.h>
   9 #include <linux/kernel.h>
  10 #include <linux/slab.h>
  11 #include <linux/string.h>
  12 #include <linux/pagemap.h>
  13 #include <linux/mutex.h>
  14
  15 #include "squashfs_fs.h"
  16 #include "squashfs_fs_sb.h"
  17 #include "squashfs_fs_i.h"
  18 #include "squashfs.h"
  19
  20 /* Read separately compressed datablock and memcopy into page cache */
  21 int squashfs_readpage_block(struct page *page, u64 block, int bsize, int expected)
  22 {
  23         struct inode *i = page->mapping->host;
  24         struct squashfs_cache_entry *buffer = squashfs_get_datablock(i->i_sb,
  25                 block, bsize);
  26         int res = buffer->error;
  27
  28         if (res)
  29                 ERROR("Unable to read page, block %llx, size %x\n", block,
  30                         bsize);
  31         else
  32                 squashfs_copy_cache(page, buffer, expected, 0);
  33
  34         squashfs_cache_put(buffer);
  35         return res;
  36 }