/* Read separately compressed datablock and memcopy into page cache */
int squashfs_readpage_block(struct page *page, u64 block, int bsize)
{
struct inode *i = page->inode;
struct squashfs_cache_entry *buffer = squashfs_get_datablock(i->i_sb,
block, bsize);
int res = buffer->error;
if (res)
ERROR("Unable to read page, block %llx, size %x\n", block,
bsize);
else
squashfs_copy_cache(page, buffer, buffer->length, 0);
squashfs_cache_put(buffer);
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;
}
