squashfs: convert squashfs_symlink_read_folio to use folio APIs

Remove use of page APIs, return the errno instead of 0, switch from
kmap_atomic to kmap_local and use folio_end_read() to unify the two exit
paths.

Link: https://lkml.kernel.org/r/20240420025029.2166544-23-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: Phillip Lougher <phillip@squashfs.org.uk>
Reviewed-by: Phillip Lougher <phillip@squashfs.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Matthew Wilcox (Oracle) 2024-04-20 03:50:17 +01:00 committed by Andrew Morton
parent 40eea5abbb
commit 675f02e5e6

View File

@ -32,20 +32,19 @@
static int squashfs_symlink_read_folio(struct file *file, struct folio *folio)
{
struct page *page = &folio->page;
struct inode *inode = page->mapping->host;
struct inode *inode = folio->mapping->host;
struct super_block *sb = inode->i_sb;
struct squashfs_sb_info *msblk = sb->s_fs_info;
int index = page->index << PAGE_SHIFT;
int index = folio_pos(folio);
u64 block = squashfs_i(inode)->start;
int offset = squashfs_i(inode)->offset;
int length = min_t(int, i_size_read(inode) - index, PAGE_SIZE);
int bytes, copied;
int bytes, copied, error;
void *pageaddr;
struct squashfs_cache_entry *entry;
TRACE("Entered squashfs_symlink_readpage, page index %ld, start block "
"%llx, offset %x\n", page->index, block, offset);
"%llx, offset %x\n", folio->index, block, offset);
/*
* Skip index bytes into symlink metadata.
@ -57,14 +56,15 @@ static int squashfs_symlink_read_folio(struct file *file, struct folio *folio)
ERROR("Unable to read symlink [%llx:%x]\n",
squashfs_i(inode)->start,
squashfs_i(inode)->offset);
goto error_out;
error = bytes;
goto out;
}
}
/*
* Read length bytes from symlink metadata. Squashfs_read_metadata
* is not used here because it can sleep and we want to use
* kmap_atomic to map the page. Instead call the underlying
* kmap_local to map the folio. Instead call the underlying
* squashfs_cache_get routine. As length bytes may overlap metadata
* blocks, we may need to call squashfs_cache_get multiple times.
*/
@ -75,29 +75,26 @@ static int squashfs_symlink_read_folio(struct file *file, struct folio *folio)
squashfs_i(inode)->start,
squashfs_i(inode)->offset);
squashfs_cache_put(entry);
goto error_out;
error = entry->error;
goto out;
}
pageaddr = kmap_atomic(page);
pageaddr = kmap_local_folio(folio, 0);
copied = squashfs_copy_data(pageaddr + bytes, entry, offset,
length - bytes);
if (copied == length - bytes)
memset(pageaddr + length, 0, PAGE_SIZE - length);
else
block = entry->next_index;
kunmap_atomic(pageaddr);
kunmap_local(pageaddr);
squashfs_cache_put(entry);
}
flush_dcache_page(page);
SetPageUptodate(page);
unlock_page(page);
return 0;
error_out:
SetPageError(page);
unlock_page(page);
return 0;
flush_dcache_folio(folio);
error = 0;
out:
folio_end_read(folio, error == 0);
return error;
}