exofs: dir_inode and directory operations
implementation of directory and inode operations. * A directory is treated as a file, and essentially contains a list of <file name, inode #> pairs for files that are found in that directory. The object IDs correspond to the files' inode numbers and are allocated using a 64bit incrementing global counter. * Each file's control block (AKA on-disk inode) is stored in its object's attributes. This applies to both regular files and other types (directories, device files, symlinks, etc.). Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
This commit is contained in:
Boaz Harrosh
657
fs/exofs/dir.c
Normal file
657
fs/exofs/dir.c
Normal file
@@ -0,0 +1,657 @@
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/*
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* Copyright (C) 2005, 2006
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* Avishay Traeger (avishay@gmail.com) (avishay@il.ibm.com)
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* Copyright (C) 2005, 2006
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* International Business Machines
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* Copyright (C) 2008, 2009
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* Boaz Harrosh <bharrosh@panasas.com>
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*
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* Copyrights for code taken from ext2:
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* Copyright (C) 1992, 1993, 1994, 1995
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* Remy Card (card@masi.ibp.fr)
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* Laboratoire MASI - Institut Blaise Pascal
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* Universite Pierre et Marie Curie (Paris VI)
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* from
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* linux/fs/minix/inode.c
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* Copyright (C) 1991, 1992 Linus Torvalds
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*
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* This file is part of exofs.
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*
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* exofs is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation. Since it is based on ext2, and the only
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* valid version of GPL for the Linux kernel is version 2, the only valid
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* version of GPL for exofs is version 2.
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*
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* exofs is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with exofs; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#include "exofs.h"
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static inline unsigned exofs_chunk_size(struct inode *inode)
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{
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return inode->i_sb->s_blocksize;
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}
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static inline void exofs_put_page(struct page *page)
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{
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kunmap(page);
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page_cache_release(page);
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}
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/* Accesses dir's inode->i_size must be called under inode lock */
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static inline unsigned long dir_pages(struct inode *inode)
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{
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return (inode->i_size + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
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}
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static unsigned exofs_last_byte(struct inode *inode, unsigned long page_nr)
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{
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loff_t last_byte = inode->i_size;
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last_byte -= page_nr << PAGE_CACHE_SHIFT;
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if (last_byte > PAGE_CACHE_SIZE)
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last_byte = PAGE_CACHE_SIZE;
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return last_byte;
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}
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static int exofs_commit_chunk(struct page *page, loff_t pos, unsigned len)
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{
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struct address_space *mapping = page->mapping;
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struct inode *dir = mapping->host;
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int err = 0;
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dir->i_version++;
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if (!PageUptodate(page))
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SetPageUptodate(page);
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if (pos+len > dir->i_size) {
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i_size_write(dir, pos+len);
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mark_inode_dirty(dir);
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}
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set_page_dirty(page);
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if (IS_DIRSYNC(dir))
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err = write_one_page(page, 1);
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else
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unlock_page(page);
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return err;
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}
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static void exofs_check_page(struct page *page)
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{
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struct inode *dir = page->mapping->host;
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unsigned chunk_size = exofs_chunk_size(dir);
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char *kaddr = page_address(page);
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unsigned offs, rec_len;
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unsigned limit = PAGE_CACHE_SIZE;
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struct exofs_dir_entry *p;
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char *error;
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/* if the page is the last one in the directory */
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if ((dir->i_size >> PAGE_CACHE_SHIFT) == page->index) {
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limit = dir->i_size & ~PAGE_CACHE_MASK;
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if (limit & (chunk_size - 1))
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goto Ebadsize;
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if (!limit)
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goto out;
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}
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for (offs = 0; offs <= limit - EXOFS_DIR_REC_LEN(1); offs += rec_len) {
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p = (struct exofs_dir_entry *)(kaddr + offs);
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rec_len = le16_to_cpu(p->rec_len);
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if (rec_len < EXOFS_DIR_REC_LEN(1))
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goto Eshort;
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if (rec_len & 3)
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goto Ealign;
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if (rec_len < EXOFS_DIR_REC_LEN(p->name_len))
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goto Enamelen;
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if (((offs + rec_len - 1) ^ offs) & ~(chunk_size-1))
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goto Espan;
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}
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if (offs != limit)
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goto Eend;
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out:
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SetPageChecked(page);
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return;
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Ebadsize:
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EXOFS_ERR("ERROR [exofs_check_page]: "
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"size of directory #%lu is not a multiple of chunk size",
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dir->i_ino
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);
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goto fail;
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Eshort:
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error = "rec_len is smaller than minimal";
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goto bad_entry;
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Ealign:
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error = "unaligned directory entry";
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goto bad_entry;
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Enamelen:
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error = "rec_len is too small for name_len";
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goto bad_entry;
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Espan:
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error = "directory entry across blocks";
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goto bad_entry;
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bad_entry:
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EXOFS_ERR(
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"ERROR [exofs_check_page]: bad entry in directory #%lu: %s - "
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"offset=%lu, inode=%llu, rec_len=%d, name_len=%d",
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dir->i_ino, error, (page->index<<PAGE_CACHE_SHIFT)+offs,
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_LLU(le64_to_cpu(p->inode_no)),
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rec_len, p->name_len);
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goto fail;
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Eend:
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p = (struct exofs_dir_entry *)(kaddr + offs);
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EXOFS_ERR("ERROR [exofs_check_page]: "
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"entry in directory #%lu spans the page boundary"
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"offset=%lu, inode=%llu",
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dir->i_ino, (page->index<<PAGE_CACHE_SHIFT)+offs,
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_LLU(le64_to_cpu(p->inode_no)));
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fail:
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SetPageChecked(page);
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SetPageError(page);
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}
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static struct page *exofs_get_page(struct inode *dir, unsigned long n)
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{
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struct address_space *mapping = dir->i_mapping;
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struct page *page = read_mapping_page(mapping, n, NULL);
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if (!IS_ERR(page)) {
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kmap(page);
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if (!PageChecked(page))
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exofs_check_page(page);
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if (PageError(page))
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goto fail;
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}
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return page;
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fail:
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exofs_put_page(page);
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return ERR_PTR(-EIO);
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}
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static inline int exofs_match(int len, const unsigned char *name,
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struct exofs_dir_entry *de)
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{
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if (len != de->name_len)
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return 0;
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if (!de->inode_no)
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return 0;
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return !memcmp(name, de->name, len);
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}
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static inline
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struct exofs_dir_entry *exofs_next_entry(struct exofs_dir_entry *p)
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{
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return (struct exofs_dir_entry *)((char *)p + le16_to_cpu(p->rec_len));
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}
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static inline unsigned
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exofs_validate_entry(char *base, unsigned offset, unsigned mask)
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{
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struct exofs_dir_entry *de = (struct exofs_dir_entry *)(base + offset);
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struct exofs_dir_entry *p =
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(struct exofs_dir_entry *)(base + (offset&mask));
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while ((char *)p < (char *)de) {
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if (p->rec_len == 0)
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break;
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p = exofs_next_entry(p);
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}
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return (char *)p - base;
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}
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static unsigned char exofs_filetype_table[EXOFS_FT_MAX] = {
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[EXOFS_FT_UNKNOWN] = DT_UNKNOWN,
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[EXOFS_FT_REG_FILE] = DT_REG,
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[EXOFS_FT_DIR] = DT_DIR,
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[EXOFS_FT_CHRDEV] = DT_CHR,
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[EXOFS_FT_BLKDEV] = DT_BLK,
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[EXOFS_FT_FIFO] = DT_FIFO,
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[EXOFS_FT_SOCK] = DT_SOCK,
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[EXOFS_FT_SYMLINK] = DT_LNK,
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};
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#define S_SHIFT 12
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static unsigned char exofs_type_by_mode[S_IFMT >> S_SHIFT] = {
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[S_IFREG >> S_SHIFT] = EXOFS_FT_REG_FILE,
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[S_IFDIR >> S_SHIFT] = EXOFS_FT_DIR,
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[S_IFCHR >> S_SHIFT] = EXOFS_FT_CHRDEV,
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[S_IFBLK >> S_SHIFT] = EXOFS_FT_BLKDEV,
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[S_IFIFO >> S_SHIFT] = EXOFS_FT_FIFO,
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[S_IFSOCK >> S_SHIFT] = EXOFS_FT_SOCK,
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[S_IFLNK >> S_SHIFT] = EXOFS_FT_SYMLINK,
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};
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static inline
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void exofs_set_de_type(struct exofs_dir_entry *de, struct inode *inode)
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{
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mode_t mode = inode->i_mode;
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de->file_type = exofs_type_by_mode[(mode & S_IFMT) >> S_SHIFT];
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}
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static int
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exofs_readdir(struct file *filp, void *dirent, filldir_t filldir)
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{
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loff_t pos = filp->f_pos;
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struct inode *inode = filp->f_path.dentry->d_inode;
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unsigned int offset = pos & ~PAGE_CACHE_MASK;
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unsigned long n = pos >> PAGE_CACHE_SHIFT;
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unsigned long npages = dir_pages(inode);
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unsigned chunk_mask = ~(exofs_chunk_size(inode)-1);
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unsigned char *types = NULL;
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int need_revalidate = (filp->f_version != inode->i_version);
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if (pos > inode->i_size - EXOFS_DIR_REC_LEN(1))
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return 0;
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types = exofs_filetype_table;
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for ( ; n < npages; n++, offset = 0) {
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char *kaddr, *limit;
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struct exofs_dir_entry *de;
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struct page *page = exofs_get_page(inode, n);
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if (IS_ERR(page)) {
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EXOFS_ERR("ERROR: "
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"bad page in #%lu",
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inode->i_ino);
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filp->f_pos += PAGE_CACHE_SIZE - offset;
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return PTR_ERR(page);
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}
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kaddr = page_address(page);
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if (unlikely(need_revalidate)) {
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if (offset) {
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offset = exofs_validate_entry(kaddr, offset,
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chunk_mask);
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filp->f_pos = (n<<PAGE_CACHE_SHIFT) + offset;
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}
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filp->f_version = inode->i_version;
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need_revalidate = 0;
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}
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de = (struct exofs_dir_entry *)(kaddr + offset);
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limit = kaddr + exofs_last_byte(inode, n) -
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EXOFS_DIR_REC_LEN(1);
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for (; (char *)de <= limit; de = exofs_next_entry(de)) {
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if (de->rec_len == 0) {
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EXOFS_ERR("ERROR: "
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"zero-length directory entry");
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exofs_put_page(page);
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return -EIO;
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}
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if (de->inode_no) {
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int over;
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unsigned char d_type = DT_UNKNOWN;
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if (types && de->file_type < EXOFS_FT_MAX)
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d_type = types[de->file_type];
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offset = (char *)de - kaddr;
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over = filldir(dirent, de->name, de->name_len,
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(n<<PAGE_CACHE_SHIFT) | offset,
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le64_to_cpu(de->inode_no),
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d_type);
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if (over) {
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exofs_put_page(page);
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return 0;
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}
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}
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filp->f_pos += le16_to_cpu(de->rec_len);
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}
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exofs_put_page(page);
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}
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return 0;
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}
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struct exofs_dir_entry *exofs_find_entry(struct inode *dir,
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struct dentry *dentry, struct page **res_page)
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{
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const unsigned char *name = dentry->d_name.name;
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int namelen = dentry->d_name.len;
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unsigned reclen = EXOFS_DIR_REC_LEN(namelen);
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unsigned long start, n;
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unsigned long npages = dir_pages(dir);
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struct page *page = NULL;
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struct exofs_i_info *oi = exofs_i(dir);
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struct exofs_dir_entry *de;
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|
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if (npages == 0)
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goto out;
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||||
|
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*res_page = NULL;
|
||||
|
||||
start = oi->i_dir_start_lookup;
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||||
if (start >= npages)
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start = 0;
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n = start;
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do {
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char *kaddr;
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page = exofs_get_page(dir, n);
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if (!IS_ERR(page)) {
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kaddr = page_address(page);
|
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de = (struct exofs_dir_entry *) kaddr;
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kaddr += exofs_last_byte(dir, n) - reclen;
|
||||
while ((char *) de <= kaddr) {
|
||||
if (de->rec_len == 0) {
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||||
EXOFS_ERR(
|
||||
"ERROR: exofs_find_entry: "
|
||||
"zero-length directory entry");
|
||||
exofs_put_page(page);
|
||||
goto out;
|
||||
}
|
||||
if (exofs_match(namelen, name, de))
|
||||
goto found;
|
||||
de = exofs_next_entry(de);
|
||||
}
|
||||
exofs_put_page(page);
|
||||
}
|
||||
if (++n >= npages)
|
||||
n = 0;
|
||||
} while (n != start);
|
||||
out:
|
||||
return NULL;
|
||||
|
||||
found:
|
||||
*res_page = page;
|
||||
oi->i_dir_start_lookup = n;
|
||||
return de;
|
||||
}
|
||||
|
||||
struct exofs_dir_entry *exofs_dotdot(struct inode *dir, struct page **p)
|
||||
{
|
||||
struct page *page = exofs_get_page(dir, 0);
|
||||
struct exofs_dir_entry *de = NULL;
|
||||
|
||||
if (!IS_ERR(page)) {
|
||||
de = exofs_next_entry(
|
||||
(struct exofs_dir_entry *)page_address(page));
|
||||
*p = page;
|
||||
}
|
||||
return de;
|
||||
}
|
||||
|
||||
ino_t exofs_inode_by_name(struct inode *dir, struct dentry *dentry)
|
||||
{
|
||||
ino_t res = 0;
|
||||
struct exofs_dir_entry *de;
|
||||
struct page *page;
|
||||
|
||||
de = exofs_find_entry(dir, dentry, &page);
|
||||
if (de) {
|
||||
res = le64_to_cpu(de->inode_no);
|
||||
exofs_put_page(page);
|
||||
}
|
||||
return res;
|
||||
}
|
||||
|
||||
int exofs_set_link(struct inode *dir, struct exofs_dir_entry *de,
|
||||
struct page *page, struct inode *inode)
|
||||
{
|
||||
loff_t pos = page_offset(page) +
|
||||
(char *) de - (char *) page_address(page);
|
||||
unsigned len = le16_to_cpu(de->rec_len);
|
||||
int err;
|
||||
|
||||
lock_page(page);
|
||||
err = exofs_write_begin(NULL, page->mapping, pos, len,
|
||||
AOP_FLAG_UNINTERRUPTIBLE, &page, NULL);
|
||||
if (err)
|
||||
EXOFS_ERR("exofs_set_link: exofs_write_begin FAILD => %d\n",
|
||||
err);
|
||||
|
||||
de->inode_no = cpu_to_le64(inode->i_ino);
|
||||
exofs_set_de_type(de, inode);
|
||||
if (likely(!err))
|
||||
err = exofs_commit_chunk(page, pos, len);
|
||||
exofs_put_page(page);
|
||||
dir->i_mtime = dir->i_ctime = CURRENT_TIME;
|
||||
mark_inode_dirty(dir);
|
||||
return err;
|
||||
}
|
||||
|
||||
int exofs_add_link(struct dentry *dentry, struct inode *inode)
|
||||
{
|
||||
struct inode *dir = dentry->d_parent->d_inode;
|
||||
const unsigned char *name = dentry->d_name.name;
|
||||
int namelen = dentry->d_name.len;
|
||||
unsigned chunk_size = exofs_chunk_size(dir);
|
||||
unsigned reclen = EXOFS_DIR_REC_LEN(namelen);
|
||||
unsigned short rec_len, name_len;
|
||||
struct page *page = NULL;
|
||||
struct exofs_sb_info *sbi = inode->i_sb->s_fs_info;
|
||||
struct exofs_dir_entry *de;
|
||||
unsigned long npages = dir_pages(dir);
|
||||
unsigned long n;
|
||||
char *kaddr;
|
||||
loff_t pos;
|
||||
int err;
|
||||
|
||||
for (n = 0; n <= npages; n++) {
|
||||
char *dir_end;
|
||||
|
||||
page = exofs_get_page(dir, n);
|
||||
err = PTR_ERR(page);
|
||||
if (IS_ERR(page))
|
||||
goto out;
|
||||
lock_page(page);
|
||||
kaddr = page_address(page);
|
||||
dir_end = kaddr + exofs_last_byte(dir, n);
|
||||
de = (struct exofs_dir_entry *)kaddr;
|
||||
kaddr += PAGE_CACHE_SIZE - reclen;
|
||||
while ((char *)de <= kaddr) {
|
||||
if ((char *)de == dir_end) {
|
||||
name_len = 0;
|
||||
rec_len = chunk_size;
|
||||
de->rec_len = cpu_to_le16(chunk_size);
|
||||
de->inode_no = 0;
|
||||
goto got_it;
|
||||
}
|
||||
if (de->rec_len == 0) {
|
||||
EXOFS_ERR("ERROR: exofs_add_link: "
|
||||
"zero-length directory entry");
|
||||
err = -EIO;
|
||||
goto out_unlock;
|
||||
}
|
||||
err = -EEXIST;
|
||||
if (exofs_match(namelen, name, de))
|
||||
goto out_unlock;
|
||||
name_len = EXOFS_DIR_REC_LEN(de->name_len);
|
||||
rec_len = le16_to_cpu(de->rec_len);
|
||||
if (!de->inode_no && rec_len >= reclen)
|
||||
goto got_it;
|
||||
if (rec_len >= name_len + reclen)
|
||||
goto got_it;
|
||||
de = (struct exofs_dir_entry *) ((char *) de + rec_len);
|
||||
}
|
||||
unlock_page(page);
|
||||
exofs_put_page(page);
|
||||
}
|
||||
|
||||
EXOFS_ERR("exofs_add_link: BAD dentry=%p or inode=%p", dentry, inode);
|
||||
return -EINVAL;
|
||||
|
||||
got_it:
|
||||
pos = page_offset(page) +
|
||||
(char *)de - (char *)page_address(page);
|
||||
err = exofs_write_begin(NULL, page->mapping, pos, rec_len, 0,
|
||||
&page, NULL);
|
||||
if (err)
|
||||
goto out_unlock;
|
||||
if (de->inode_no) {
|
||||
struct exofs_dir_entry *de1 =
|
||||
(struct exofs_dir_entry *)((char *)de + name_len);
|
||||
de1->rec_len = cpu_to_le16(rec_len - name_len);
|
||||
de->rec_len = cpu_to_le16(name_len);
|
||||
de = de1;
|
||||
}
|
||||
de->name_len = namelen;
|
||||
memcpy(de->name, name, namelen);
|
||||
de->inode_no = cpu_to_le64(inode->i_ino);
|
||||
exofs_set_de_type(de, inode);
|
||||
err = exofs_commit_chunk(page, pos, rec_len);
|
||||
dir->i_mtime = dir->i_ctime = CURRENT_TIME;
|
||||
mark_inode_dirty(dir);
|
||||
sbi->s_numfiles++;
|
||||
|
||||
out_put:
|
||||
exofs_put_page(page);
|
||||
out:
|
||||
return err;
|
||||
out_unlock:
|
||||
unlock_page(page);
|
||||
goto out_put;
|
||||
}
|
||||
|
||||
int exofs_delete_entry(struct exofs_dir_entry *dir, struct page *page)
|
||||
{
|
||||
struct address_space *mapping = page->mapping;
|
||||
struct inode *inode = mapping->host;
|
||||
struct exofs_sb_info *sbi = inode->i_sb->s_fs_info;
|
||||
char *kaddr = page_address(page);
|
||||
unsigned from = ((char *)dir - kaddr) & ~(exofs_chunk_size(inode)-1);
|
||||
unsigned to = ((char *)dir - kaddr) + le16_to_cpu(dir->rec_len);
|
||||
loff_t pos;
|
||||
struct exofs_dir_entry *pde = NULL;
|
||||
struct exofs_dir_entry *de = (struct exofs_dir_entry *) (kaddr + from);
|
||||
int err;
|
||||
|
||||
while (de < dir) {
|
||||
if (de->rec_len == 0) {
|
||||
EXOFS_ERR("ERROR: exofs_delete_entry:"
|
||||
"zero-length directory entry");
|
||||
err = -EIO;
|
||||
goto out;
|
||||
}
|
||||
pde = de;
|
||||
de = exofs_next_entry(de);
|
||||
}
|
||||
if (pde)
|
||||
from = (char *)pde - (char *)page_address(page);
|
||||
pos = page_offset(page) + from;
|
||||
lock_page(page);
|
||||
err = exofs_write_begin(NULL, page->mapping, pos, to - from, 0,
|
||||
&page, NULL);
|
||||
if (err)
|
||||
EXOFS_ERR("exofs_delete_entry: exofs_write_begin FAILD => %d\n",
|
||||
err);
|
||||
if (pde)
|
||||
pde->rec_len = cpu_to_le16(to - from);
|
||||
dir->inode_no = 0;
|
||||
if (likely(!err))
|
||||
err = exofs_commit_chunk(page, pos, to - from);
|
||||
inode->i_ctime = inode->i_mtime = CURRENT_TIME;
|
||||
mark_inode_dirty(inode);
|
||||
sbi->s_numfiles--;
|
||||
out:
|
||||
exofs_put_page(page);
|
||||
return err;
|
||||
}
|
||||
|
||||
/* kept aligned on 4 bytes */
|
||||
#define THIS_DIR ".\0\0"
|
||||
#define PARENT_DIR "..\0"
|
||||
|
||||
int exofs_make_empty(struct inode *inode, struct inode *parent)
|
||||
{
|
||||
struct address_space *mapping = inode->i_mapping;
|
||||
struct page *page = grab_cache_page(mapping, 0);
|
||||
unsigned chunk_size = exofs_chunk_size(inode);
|
||||
struct exofs_dir_entry *de;
|
||||
int err;
|
||||
void *kaddr;
|
||||
|
||||
if (!page)
|
||||
return -ENOMEM;
|
||||
|
||||
err = exofs_write_begin(NULL, page->mapping, 0, chunk_size, 0,
|
||||
&page, NULL);
|
||||
if (err) {
|
||||
unlock_page(page);
|
||||
goto fail;
|
||||
}
|
||||
|
||||
kaddr = kmap_atomic(page, KM_USER0);
|
||||
de = (struct exofs_dir_entry *)kaddr;
|
||||
de->name_len = 1;
|
||||
de->rec_len = cpu_to_le16(EXOFS_DIR_REC_LEN(1));
|
||||
memcpy(de->name, THIS_DIR, sizeof(THIS_DIR));
|
||||
de->inode_no = cpu_to_le64(inode->i_ino);
|
||||
exofs_set_de_type(de, inode);
|
||||
|
||||
de = (struct exofs_dir_entry *)(kaddr + EXOFS_DIR_REC_LEN(1));
|
||||
de->name_len = 2;
|
||||
de->rec_len = cpu_to_le16(chunk_size - EXOFS_DIR_REC_LEN(1));
|
||||
de->inode_no = cpu_to_le64(parent->i_ino);
|
||||
memcpy(de->name, PARENT_DIR, sizeof(PARENT_DIR));
|
||||
exofs_set_de_type(de, inode);
|
||||
kunmap_atomic(page, KM_USER0);
|
||||
err = exofs_commit_chunk(page, 0, chunk_size);
|
||||
fail:
|
||||
page_cache_release(page);
|
||||
return err;
|
||||
}
|
||||
|
||||
int exofs_empty_dir(struct inode *inode)
|
||||
{
|
||||
struct page *page = NULL;
|
||||
unsigned long i, npages = dir_pages(inode);
|
||||
|
||||
for (i = 0; i < npages; i++) {
|
||||
char *kaddr;
|
||||
struct exofs_dir_entry *de;
|
||||
page = exofs_get_page(inode, i);
|
||||
|
||||
if (IS_ERR(page))
|
||||
continue;
|
||||
|
||||
kaddr = page_address(page);
|
||||
de = (struct exofs_dir_entry *)kaddr;
|
||||
kaddr += exofs_last_byte(inode, i) - EXOFS_DIR_REC_LEN(1);
|
||||
|
||||
while ((char *)de <= kaddr) {
|
||||
if (de->rec_len == 0) {
|
||||
EXOFS_ERR("ERROR: exofs_empty_dir: "
|
||||
"zero-length directory entry"
|
||||
"kaddr=%p, de=%p\n", kaddr, de);
|
||||
goto not_empty;
|
||||
}
|
||||
if (de->inode_no != 0) {
|
||||
/* check for . and .. */
|
||||
if (de->name[0] != '.')
|
||||
goto not_empty;
|
||||
if (de->name_len > 2)
|
||||
goto not_empty;
|
||||
if (de->name_len < 2) {
|
||||
if (le64_to_cpu(de->inode_no) !=
|
||||
inode->i_ino)
|
||||
goto not_empty;
|
||||
} else if (de->name[1] != '.')
|
||||
goto not_empty;
|
||||
}
|
||||
de = exofs_next_entry(de);
|
||||
}
|
||||
exofs_put_page(page);
|
||||
}
|
||||
return 1;
|
||||
|
||||
not_empty:
|
||||
exofs_put_page(page);
|
||||
return 0;
|
||||
}
|
||||
|
||||
const struct file_operations exofs_dir_operations = {
|
||||
.llseek = generic_file_llseek,
|
||||
.read = generic_read_dir,
|
||||
.readdir = exofs_readdir,
|
||||
};
|
||||
Reference in New Issue
Block a user