2009-04-07 10:01:34 +08:00
|
|
|
/*
|
|
|
|
* dir.c - NILFS directory entry operations
|
|
|
|
*
|
|
|
|
* Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
|
|
|
|
*
|
|
|
|
* This program is free software; you can redistribute it and/or modify
|
|
|
|
* it under the terms of the GNU General Public License as published by
|
|
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
|
|
* (at your option) any later version.
|
|
|
|
*
|
|
|
|
* This program is distributed in the hope that it will be useful,
|
|
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
|
|
* GNU General Public License for more details.
|
|
|
|
*
|
|
|
|
* You should have received a copy of the GNU General Public License
|
|
|
|
* along with this program; if not, write to the Free Software
|
|
|
|
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
|
|
|
*
|
|
|
|
* Modified for NILFS by Amagai Yoshiji <amagai@osrg.net>
|
|
|
|
*/
|
|
|
|
/*
|
|
|
|
* linux/fs/ext2/dir.c
|
|
|
|
*
|
|
|
|
* Copyright (C) 1992, 1993, 1994, 1995
|
|
|
|
* Remy Card (card@masi.ibp.fr)
|
|
|
|
* Laboratoire MASI - Institut Blaise Pascal
|
|
|
|
* Universite Pierre et Marie Curie (Paris VI)
|
|
|
|
*
|
|
|
|
* from
|
|
|
|
*
|
|
|
|
* linux/fs/minix/dir.c
|
|
|
|
*
|
|
|
|
* Copyright (C) 1991, 1992 Linus Torvalds
|
|
|
|
*
|
|
|
|
* ext2 directory handling functions
|
|
|
|
*
|
|
|
|
* Big-endian to little-endian byte-swapping/bitmaps by
|
|
|
|
* David S. Miller (davem@caip.rutgers.edu), 1995
|
|
|
|
*
|
|
|
|
* All code that works with directory layout had been switched to pagecache
|
|
|
|
* and moved here. AV
|
|
|
|
*/
|
|
|
|
|
|
|
|
#include <linux/pagemap.h>
|
|
|
|
#include "nilfs.h"
|
|
|
|
#include "page.h"
|
|
|
|
|
|
|
|
/*
|
|
|
|
* nilfs uses block-sized chunks. Arguably, sector-sized ones would be
|
|
|
|
* more robust, but we have what we have
|
|
|
|
*/
|
|
|
|
static inline unsigned nilfs_chunk_size(struct inode *inode)
|
|
|
|
{
|
|
|
|
return inode->i_sb->s_blocksize;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void nilfs_put_page(struct page *page)
|
|
|
|
{
|
|
|
|
kunmap(page);
|
|
|
|
page_cache_release(page);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline unsigned long dir_pages(struct inode *inode)
|
|
|
|
{
|
|
|
|
return (inode->i_size+PAGE_CACHE_SIZE-1)>>PAGE_CACHE_SHIFT;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Return the offset into page `page_nr' of the last valid
|
|
|
|
* byte in that page, plus one.
|
|
|
|
*/
|
|
|
|
static unsigned nilfs_last_byte(struct inode *inode, unsigned long page_nr)
|
|
|
|
{
|
|
|
|
unsigned last_byte = inode->i_size;
|
|
|
|
|
|
|
|
last_byte -= page_nr << PAGE_CACHE_SHIFT;
|
|
|
|
if (last_byte > PAGE_CACHE_SIZE)
|
|
|
|
last_byte = PAGE_CACHE_SIZE;
|
|
|
|
return last_byte;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int nilfs_prepare_chunk_uninterruptible(struct page *page,
|
|
|
|
struct address_space *mapping,
|
|
|
|
unsigned from, unsigned to)
|
|
|
|
{
|
|
|
|
loff_t pos = page_offset(page) + from;
|
|
|
|
return block_write_begin(NULL, mapping, pos, to - from,
|
|
|
|
AOP_FLAG_UNINTERRUPTIBLE, &page,
|
|
|
|
NULL, nilfs_get_block);
|
|
|
|
}
|
|
|
|
|
|
|
|
static int nilfs_prepare_chunk(struct page *page,
|
|
|
|
struct address_space *mapping,
|
|
|
|
unsigned from, unsigned to)
|
|
|
|
{
|
|
|
|
loff_t pos = page_offset(page) + from;
|
|
|
|
return block_write_begin(NULL, mapping, pos, to - from, 0, &page,
|
|
|
|
NULL, nilfs_get_block);
|
|
|
|
}
|
|
|
|
|
2009-11-27 18:41:11 +08:00
|
|
|
static void nilfs_commit_chunk(struct page *page,
|
|
|
|
struct address_space *mapping,
|
|
|
|
unsigned from, unsigned to)
|
2009-04-07 10:01:34 +08:00
|
|
|
{
|
|
|
|
struct inode *dir = mapping->host;
|
|
|
|
struct nilfs_sb_info *sbi = NILFS_SB(dir->i_sb);
|
|
|
|
loff_t pos = page_offset(page) + from;
|
|
|
|
unsigned len = to - from;
|
|
|
|
unsigned nr_dirty, copied;
|
|
|
|
int err;
|
|
|
|
|
|
|
|
nr_dirty = nilfs_page_count_clean_buffers(page, from, to);
|
|
|
|
copied = block_write_end(NULL, mapping, pos, len, len, page, NULL);
|
2009-11-27 18:41:12 +08:00
|
|
|
if (pos + copied > dir->i_size)
|
2009-04-07 10:01:34 +08:00
|
|
|
i_size_write(dir, pos + copied);
|
|
|
|
if (IS_DIRSYNC(dir))
|
|
|
|
nilfs_set_transaction_flag(NILFS_TI_SYNC);
|
|
|
|
err = nilfs_set_file_dirty(sbi, dir, nr_dirty);
|
2009-11-27 18:41:11 +08:00
|
|
|
WARN_ON(err); /* do not happen */
|
2009-04-07 10:01:34 +08:00
|
|
|
unlock_page(page);
|
|
|
|
}
|
|
|
|
|
|
|
|
static void nilfs_check_page(struct page *page)
|
|
|
|
{
|
|
|
|
struct inode *dir = page->mapping->host;
|
|
|
|
struct super_block *sb = dir->i_sb;
|
|
|
|
unsigned chunk_size = nilfs_chunk_size(dir);
|
|
|
|
char *kaddr = page_address(page);
|
|
|
|
unsigned offs, rec_len;
|
|
|
|
unsigned limit = PAGE_CACHE_SIZE;
|
|
|
|
struct nilfs_dir_entry *p;
|
|
|
|
char *error;
|
|
|
|
|
|
|
|
if ((dir->i_size >> PAGE_CACHE_SHIFT) == page->index) {
|
|
|
|
limit = dir->i_size & ~PAGE_CACHE_MASK;
|
|
|
|
if (limit & (chunk_size - 1))
|
|
|
|
goto Ebadsize;
|
|
|
|
if (!limit)
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
for (offs = 0; offs <= limit - NILFS_DIR_REC_LEN(1); offs += rec_len) {
|
|
|
|
p = (struct nilfs_dir_entry *)(kaddr + offs);
|
|
|
|
rec_len = le16_to_cpu(p->rec_len);
|
|
|
|
|
|
|
|
if (rec_len < NILFS_DIR_REC_LEN(1))
|
|
|
|
goto Eshort;
|
|
|
|
if (rec_len & 3)
|
|
|
|
goto Ealign;
|
|
|
|
if (rec_len < NILFS_DIR_REC_LEN(p->name_len))
|
|
|
|
goto Enamelen;
|
|
|
|
if (((offs + rec_len - 1) ^ offs) & ~(chunk_size-1))
|
|
|
|
goto Espan;
|
|
|
|
}
|
|
|
|
if (offs != limit)
|
|
|
|
goto Eend;
|
|
|
|
out:
|
|
|
|
SetPageChecked(page);
|
|
|
|
return;
|
|
|
|
|
|
|
|
/* Too bad, we had an error */
|
|
|
|
|
|
|
|
Ebadsize:
|
|
|
|
nilfs_error(sb, "nilfs_check_page",
|
|
|
|
"size of directory #%lu is not a multiple of chunk size",
|
|
|
|
dir->i_ino
|
|
|
|
);
|
|
|
|
goto fail;
|
|
|
|
Eshort:
|
|
|
|
error = "rec_len is smaller than minimal";
|
|
|
|
goto bad_entry;
|
|
|
|
Ealign:
|
|
|
|
error = "unaligned directory entry";
|
|
|
|
goto bad_entry;
|
|
|
|
Enamelen:
|
|
|
|
error = "rec_len is too small for name_len";
|
|
|
|
goto bad_entry;
|
|
|
|
Espan:
|
|
|
|
error = "directory entry across blocks";
|
|
|
|
bad_entry:
|
|
|
|
nilfs_error(sb, "nilfs_check_page", "bad entry in directory #%lu: %s - "
|
|
|
|
"offset=%lu, inode=%lu, rec_len=%d, name_len=%d",
|
|
|
|
dir->i_ino, error, (page->index<<PAGE_CACHE_SHIFT)+offs,
|
|
|
|
(unsigned long) le64_to_cpu(p->inode),
|
|
|
|
rec_len, p->name_len);
|
|
|
|
goto fail;
|
|
|
|
Eend:
|
|
|
|
p = (struct nilfs_dir_entry *)(kaddr + offs);
|
|
|
|
nilfs_error(sb, "nilfs_check_page",
|
|
|
|
"entry in directory #%lu spans the page boundary"
|
|
|
|
"offset=%lu, inode=%lu",
|
|
|
|
dir->i_ino, (page->index<<PAGE_CACHE_SHIFT)+offs,
|
|
|
|
(unsigned long) le64_to_cpu(p->inode));
|
|
|
|
fail:
|
|
|
|
SetPageChecked(page);
|
|
|
|
SetPageError(page);
|
|
|
|
}
|
|
|
|
|
|
|
|
static struct page *nilfs_get_page(struct inode *dir, unsigned long n)
|
|
|
|
{
|
|
|
|
struct address_space *mapping = dir->i_mapping;
|
2010-07-24 16:09:10 +08:00
|
|
|
struct page *page = read_mapping_page(mapping, n, NULL);
|
|
|
|
|
2009-04-07 10:01:34 +08:00
|
|
|
if (!IS_ERR(page)) {
|
|
|
|
kmap(page);
|
|
|
|
if (!PageChecked(page))
|
|
|
|
nilfs_check_page(page);
|
|
|
|
if (PageError(page))
|
|
|
|
goto fail;
|
|
|
|
}
|
|
|
|
return page;
|
|
|
|
|
|
|
|
fail:
|
|
|
|
nilfs_put_page(page);
|
|
|
|
return ERR_PTR(-EIO);
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* NOTE! unlike strncmp, nilfs_match returns 1 for success, 0 for failure.
|
|
|
|
*
|
|
|
|
* len <= NILFS_NAME_LEN and de != NULL are guaranteed by caller.
|
|
|
|
*/
|
|
|
|
static int
|
2010-02-01 10:03:58 +08:00
|
|
|
nilfs_match(int len, const unsigned char *name, struct nilfs_dir_entry *de)
|
2009-04-07 10:01:34 +08:00
|
|
|
{
|
|
|
|
if (len != de->name_len)
|
|
|
|
return 0;
|
|
|
|
if (!de->inode)
|
|
|
|
return 0;
|
|
|
|
return !memcmp(name, de->name, len);
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* p is at least 6 bytes before the end of page
|
|
|
|
*/
|
|
|
|
static struct nilfs_dir_entry *nilfs_next_entry(struct nilfs_dir_entry *p)
|
|
|
|
{
|
|
|
|
return (struct nilfs_dir_entry *)((char *)p + le16_to_cpu(p->rec_len));
|
|
|
|
}
|
|
|
|
|
|
|
|
static unsigned char
|
|
|
|
nilfs_filetype_table[NILFS_FT_MAX] = {
|
|
|
|
[NILFS_FT_UNKNOWN] = DT_UNKNOWN,
|
|
|
|
[NILFS_FT_REG_FILE] = DT_REG,
|
|
|
|
[NILFS_FT_DIR] = DT_DIR,
|
|
|
|
[NILFS_FT_CHRDEV] = DT_CHR,
|
|
|
|
[NILFS_FT_BLKDEV] = DT_BLK,
|
|
|
|
[NILFS_FT_FIFO] = DT_FIFO,
|
|
|
|
[NILFS_FT_SOCK] = DT_SOCK,
|
|
|
|
[NILFS_FT_SYMLINK] = DT_LNK,
|
|
|
|
};
|
|
|
|
|
|
|
|
#define S_SHIFT 12
|
|
|
|
static unsigned char
|
|
|
|
nilfs_type_by_mode[S_IFMT >> S_SHIFT] = {
|
|
|
|
[S_IFREG >> S_SHIFT] = NILFS_FT_REG_FILE,
|
|
|
|
[S_IFDIR >> S_SHIFT] = NILFS_FT_DIR,
|
|
|
|
[S_IFCHR >> S_SHIFT] = NILFS_FT_CHRDEV,
|
|
|
|
[S_IFBLK >> S_SHIFT] = NILFS_FT_BLKDEV,
|
|
|
|
[S_IFIFO >> S_SHIFT] = NILFS_FT_FIFO,
|
|
|
|
[S_IFSOCK >> S_SHIFT] = NILFS_FT_SOCK,
|
|
|
|
[S_IFLNK >> S_SHIFT] = NILFS_FT_SYMLINK,
|
|
|
|
};
|
|
|
|
|
|
|
|
static void nilfs_set_de_type(struct nilfs_dir_entry *de, struct inode *inode)
|
|
|
|
{
|
|
|
|
mode_t mode = inode->i_mode;
|
|
|
|
|
|
|
|
de->file_type = nilfs_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
|
|
|
|
}
|
|
|
|
|
|
|
|
static int nilfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
|
|
|
|
{
|
|
|
|
loff_t pos = filp->f_pos;
|
|
|
|
struct inode *inode = filp->f_dentry->d_inode;
|
|
|
|
struct super_block *sb = inode->i_sb;
|
|
|
|
unsigned int offset = pos & ~PAGE_CACHE_MASK;
|
|
|
|
unsigned long n = pos >> PAGE_CACHE_SHIFT;
|
|
|
|
unsigned long npages = dir_pages(inode);
|
|
|
|
/* unsigned chunk_mask = ~(nilfs_chunk_size(inode)-1); */
|
|
|
|
unsigned char *types = NULL;
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
if (pos > inode->i_size - NILFS_DIR_REC_LEN(1))
|
|
|
|
goto success;
|
|
|
|
|
|
|
|
types = nilfs_filetype_table;
|
|
|
|
|
|
|
|
for ( ; n < npages; n++, offset = 0) {
|
|
|
|
char *kaddr, *limit;
|
|
|
|
struct nilfs_dir_entry *de;
|
|
|
|
struct page *page = nilfs_get_page(inode, n);
|
|
|
|
|
|
|
|
if (IS_ERR(page)) {
|
|
|
|
nilfs_error(sb, __func__, "bad page in #%lu",
|
|
|
|
inode->i_ino);
|
|
|
|
filp->f_pos += PAGE_CACHE_SIZE - offset;
|
|
|
|
ret = -EIO;
|
|
|
|
goto done;
|
|
|
|
}
|
|
|
|
kaddr = page_address(page);
|
|
|
|
de = (struct nilfs_dir_entry *)(kaddr + offset);
|
|
|
|
limit = kaddr + nilfs_last_byte(inode, n) -
|
|
|
|
NILFS_DIR_REC_LEN(1);
|
|
|
|
for ( ; (char *)de <= limit; de = nilfs_next_entry(de)) {
|
|
|
|
if (de->rec_len == 0) {
|
|
|
|
nilfs_error(sb, __func__,
|
|
|
|
"zero-length directory entry");
|
|
|
|
ret = -EIO;
|
|
|
|
nilfs_put_page(page);
|
|
|
|
goto done;
|
|
|
|
}
|
|
|
|
if (de->inode) {
|
|
|
|
int over;
|
|
|
|
unsigned char d_type = DT_UNKNOWN;
|
|
|
|
|
|
|
|
if (types && de->file_type < NILFS_FT_MAX)
|
|
|
|
d_type = types[de->file_type];
|
|
|
|
|
|
|
|
offset = (char *)de - kaddr;
|
|
|
|
over = filldir(dirent, de->name, de->name_len,
|
|
|
|
(n<<PAGE_CACHE_SHIFT) | offset,
|
|
|
|
le64_to_cpu(de->inode), d_type);
|
|
|
|
if (over) {
|
|
|
|
nilfs_put_page(page);
|
|
|
|
goto success;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
filp->f_pos += le16_to_cpu(de->rec_len);
|
|
|
|
}
|
|
|
|
nilfs_put_page(page);
|
|
|
|
}
|
|
|
|
|
|
|
|
success:
|
|
|
|
ret = 0;
|
|
|
|
done:
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* nilfs_find_entry()
|
|
|
|
*
|
|
|
|
* finds an entry in the specified directory with the wanted name. It
|
|
|
|
* returns the page in which the entry was found, and the entry itself
|
|
|
|
* (as a parameter - res_dir). Page is returned mapped and unlocked.
|
|
|
|
* Entry is guaranteed to be valid.
|
|
|
|
*/
|
|
|
|
struct nilfs_dir_entry *
|
2010-02-01 10:02:09 +08:00
|
|
|
nilfs_find_entry(struct inode *dir, const struct qstr *qstr,
|
2009-04-07 10:01:34 +08:00
|
|
|
struct page **res_page)
|
|
|
|
{
|
2010-02-01 10:02:09 +08:00
|
|
|
const unsigned char *name = qstr->name;
|
|
|
|
int namelen = qstr->len;
|
2009-04-07 10:01:34 +08:00
|
|
|
unsigned reclen = NILFS_DIR_REC_LEN(namelen);
|
|
|
|
unsigned long start, n;
|
|
|
|
unsigned long npages = dir_pages(dir);
|
|
|
|
struct page *page = NULL;
|
|
|
|
struct nilfs_inode_info *ei = NILFS_I(dir);
|
|
|
|
struct nilfs_dir_entry *de;
|
|
|
|
|
|
|
|
if (npages == 0)
|
|
|
|
goto out;
|
|
|
|
|
|
|
|
/* OFFSET_CACHE */
|
|
|
|
*res_page = NULL;
|
|
|
|
|
|
|
|
start = ei->i_dir_start_lookup;
|
|
|
|
if (start >= npages)
|
|
|
|
start = 0;
|
|
|
|
n = start;
|
|
|
|
do {
|
|
|
|
char *kaddr;
|
|
|
|
page = nilfs_get_page(dir, n);
|
|
|
|
if (!IS_ERR(page)) {
|
|
|
|
kaddr = page_address(page);
|
|
|
|
de = (struct nilfs_dir_entry *)kaddr;
|
|
|
|
kaddr += nilfs_last_byte(dir, n) - reclen;
|
|
|
|
while ((char *) de <= kaddr) {
|
|
|
|
if (de->rec_len == 0) {
|
|
|
|
nilfs_error(dir->i_sb, __func__,
|
|
|
|
"zero-length directory entry");
|
|
|
|
nilfs_put_page(page);
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
if (nilfs_match(namelen, name, de))
|
|
|
|
goto found;
|
|
|
|
de = nilfs_next_entry(de);
|
|
|
|
}
|
|
|
|
nilfs_put_page(page);
|
|
|
|
}
|
|
|
|
if (++n >= npages)
|
|
|
|
n = 0;
|
|
|
|
/* next page is past the blocks we've got */
|
|
|
|
if (unlikely(n > (dir->i_blocks >> (PAGE_CACHE_SHIFT - 9)))) {
|
|
|
|
nilfs_error(dir->i_sb, __func__,
|
2010-03-14 02:17:45 +08:00
|
|
|
"dir %lu size %lld exceeds block count %llu",
|
2009-04-07 10:01:34 +08:00
|
|
|
dir->i_ino, dir->i_size,
|
|
|
|
(unsigned long long)dir->i_blocks);
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
} while (n != start);
|
|
|
|
out:
|
|
|
|
return NULL;
|
|
|
|
|
|
|
|
found:
|
|
|
|
*res_page = page;
|
|
|
|
ei->i_dir_start_lookup = n;
|
|
|
|
return de;
|
|
|
|
}
|
|
|
|
|
|
|
|
struct nilfs_dir_entry *nilfs_dotdot(struct inode *dir, struct page **p)
|
|
|
|
{
|
|
|
|
struct page *page = nilfs_get_page(dir, 0);
|
|
|
|
struct nilfs_dir_entry *de = NULL;
|
|
|
|
|
|
|
|
if (!IS_ERR(page)) {
|
|
|
|
de = nilfs_next_entry(
|
|
|
|
(struct nilfs_dir_entry *)page_address(page));
|
|
|
|
*p = page;
|
|
|
|
}
|
|
|
|
return de;
|
|
|
|
}
|
|
|
|
|
2010-02-01 10:02:09 +08:00
|
|
|
ino_t nilfs_inode_by_name(struct inode *dir, const struct qstr *qstr)
|
2009-04-07 10:01:34 +08:00
|
|
|
{
|
|
|
|
ino_t res = 0;
|
|
|
|
struct nilfs_dir_entry *de;
|
|
|
|
struct page *page;
|
|
|
|
|
2010-02-01 10:02:09 +08:00
|
|
|
de = nilfs_find_entry(dir, qstr, &page);
|
2009-04-07 10:01:34 +08:00
|
|
|
if (de) {
|
|
|
|
res = le64_to_cpu(de->inode);
|
|
|
|
kunmap(page);
|
|
|
|
page_cache_release(page);
|
|
|
|
}
|
|
|
|
return res;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Releases the page */
|
|
|
|
void nilfs_set_link(struct inode *dir, struct nilfs_dir_entry *de,
|
|
|
|
struct page *page, struct inode *inode)
|
|
|
|
{
|
|
|
|
unsigned from = (char *) de - (char *) page_address(page);
|
|
|
|
unsigned to = from + le16_to_cpu(de->rec_len);
|
|
|
|
struct address_space *mapping = page->mapping;
|
|
|
|
int err;
|
|
|
|
|
|
|
|
lock_page(page);
|
|
|
|
err = nilfs_prepare_chunk_uninterruptible(page, mapping, from, to);
|
|
|
|
BUG_ON(err);
|
|
|
|
de->inode = cpu_to_le64(inode->i_ino);
|
|
|
|
nilfs_set_de_type(de, inode);
|
2009-11-27 18:41:11 +08:00
|
|
|
nilfs_commit_chunk(page, mapping, from, to);
|
2009-04-07 10:01:34 +08:00
|
|
|
nilfs_put_page(page);
|
|
|
|
dir->i_mtime = dir->i_ctime = CURRENT_TIME;
|
|
|
|
/* NILFS_I(dir)->i_flags &= ~NILFS_BTREE_FL; */
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Parent is locked.
|
|
|
|
*/
|
|
|
|
int nilfs_add_link(struct dentry *dentry, struct inode *inode)
|
|
|
|
{
|
|
|
|
struct inode *dir = dentry->d_parent->d_inode;
|
2010-02-01 10:03:58 +08:00
|
|
|
const unsigned char *name = dentry->d_name.name;
|
2009-04-07 10:01:34 +08:00
|
|
|
int namelen = dentry->d_name.len;
|
|
|
|
unsigned chunk_size = nilfs_chunk_size(dir);
|
|
|
|
unsigned reclen = NILFS_DIR_REC_LEN(namelen);
|
|
|
|
unsigned short rec_len, name_len;
|
|
|
|
struct page *page = NULL;
|
|
|
|
struct nilfs_dir_entry *de;
|
|
|
|
unsigned long npages = dir_pages(dir);
|
|
|
|
unsigned long n;
|
|
|
|
char *kaddr;
|
|
|
|
unsigned from, to;
|
|
|
|
int err;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* We take care of directory expansion in the same loop.
|
|
|
|
* This code plays outside i_size, so it locks the page
|
|
|
|
* to protect that region.
|
|
|
|
*/
|
|
|
|
for (n = 0; n <= npages; n++) {
|
|
|
|
char *dir_end;
|
|
|
|
|
|
|
|
page = nilfs_get_page(dir, n);
|
|
|
|
err = PTR_ERR(page);
|
|
|
|
if (IS_ERR(page))
|
|
|
|
goto out;
|
|
|
|
lock_page(page);
|
|
|
|
kaddr = page_address(page);
|
|
|
|
dir_end = kaddr + nilfs_last_byte(dir, n);
|
|
|
|
de = (struct nilfs_dir_entry *)kaddr;
|
|
|
|
kaddr += PAGE_CACHE_SIZE - reclen;
|
|
|
|
while ((char *)de <= kaddr) {
|
|
|
|
if ((char *)de == dir_end) {
|
|
|
|
/* We hit i_size */
|
|
|
|
name_len = 0;
|
|
|
|
rec_len = chunk_size;
|
|
|
|
de->rec_len = cpu_to_le16(chunk_size);
|
|
|
|
de->inode = 0;
|
|
|
|
goto got_it;
|
|
|
|
}
|
|
|
|
if (de->rec_len == 0) {
|
|
|
|
nilfs_error(dir->i_sb, __func__,
|
|
|
|
"zero-length directory entry");
|
|
|
|
err = -EIO;
|
|
|
|
goto out_unlock;
|
|
|
|
}
|
|
|
|
err = -EEXIST;
|
|
|
|
if (nilfs_match(namelen, name, de))
|
|
|
|
goto out_unlock;
|
|
|
|
name_len = NILFS_DIR_REC_LEN(de->name_len);
|
|
|
|
rec_len = le16_to_cpu(de->rec_len);
|
|
|
|
if (!de->inode && rec_len >= reclen)
|
|
|
|
goto got_it;
|
|
|
|
if (rec_len >= name_len + reclen)
|
|
|
|
goto got_it;
|
|
|
|
de = (struct nilfs_dir_entry *)((char *)de + rec_len);
|
|
|
|
}
|
|
|
|
unlock_page(page);
|
|
|
|
nilfs_put_page(page);
|
|
|
|
}
|
|
|
|
BUG();
|
|
|
|
return -EINVAL;
|
|
|
|
|
|
|
|
got_it:
|
|
|
|
from = (char *)de - (char *)page_address(page);
|
|
|
|
to = from + rec_len;
|
|
|
|
err = nilfs_prepare_chunk(page, page->mapping, from, to);
|
|
|
|
if (err)
|
|
|
|
goto out_unlock;
|
|
|
|
if (de->inode) {
|
|
|
|
struct nilfs_dir_entry *de1;
|
|
|
|
|
|
|
|
de1 = (struct nilfs_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 = cpu_to_le64(inode->i_ino);
|
|
|
|
nilfs_set_de_type(de, inode);
|
2009-11-27 18:41:11 +08:00
|
|
|
nilfs_commit_chunk(page, page->mapping, from, to);
|
2009-04-07 10:01:34 +08:00
|
|
|
dir->i_mtime = dir->i_ctime = CURRENT_TIME;
|
|
|
|
/* NILFS_I(dir)->i_flags &= ~NILFS_BTREE_FL; */
|
2009-11-27 18:41:14 +08:00
|
|
|
nilfs_mark_inode_dirty(dir);
|
2009-04-07 10:01:34 +08:00
|
|
|
/* OFFSET_CACHE */
|
|
|
|
out_put:
|
|
|
|
nilfs_put_page(page);
|
|
|
|
out:
|
|
|
|
return err;
|
|
|
|
out_unlock:
|
|
|
|
unlock_page(page);
|
|
|
|
goto out_put;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* nilfs_delete_entry deletes a directory entry by merging it with the
|
|
|
|
* previous entry. Page is up-to-date. Releases the page.
|
|
|
|
*/
|
|
|
|
int nilfs_delete_entry(struct nilfs_dir_entry *dir, struct page *page)
|
|
|
|
{
|
|
|
|
struct address_space *mapping = page->mapping;
|
|
|
|
struct inode *inode = mapping->host;
|
|
|
|
char *kaddr = page_address(page);
|
|
|
|
unsigned from = ((char *)dir - kaddr) & ~(nilfs_chunk_size(inode) - 1);
|
|
|
|
unsigned to = ((char *)dir - kaddr) + le16_to_cpu(dir->rec_len);
|
|
|
|
struct nilfs_dir_entry *pde = NULL;
|
|
|
|
struct nilfs_dir_entry *de = (struct nilfs_dir_entry *)(kaddr + from);
|
|
|
|
int err;
|
|
|
|
|
|
|
|
while ((char *)de < (char *)dir) {
|
|
|
|
if (de->rec_len == 0) {
|
|
|
|
nilfs_error(inode->i_sb, __func__,
|
|
|
|
"zero-length directory entry");
|
|
|
|
err = -EIO;
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
pde = de;
|
|
|
|
de = nilfs_next_entry(de);
|
|
|
|
}
|
|
|
|
if (pde)
|
|
|
|
from = (char *)pde - (char *)page_address(page);
|
|
|
|
lock_page(page);
|
|
|
|
err = nilfs_prepare_chunk(page, mapping, from, to);
|
|
|
|
BUG_ON(err);
|
|
|
|
if (pde)
|
|
|
|
pde->rec_len = cpu_to_le16(to - from);
|
|
|
|
dir->inode = 0;
|
2009-11-27 18:41:11 +08:00
|
|
|
nilfs_commit_chunk(page, mapping, from, to);
|
2009-04-07 10:01:34 +08:00
|
|
|
inode->i_ctime = inode->i_mtime = CURRENT_TIME;
|
|
|
|
/* NILFS_I(inode)->i_flags &= ~NILFS_BTREE_FL; */
|
|
|
|
out:
|
|
|
|
nilfs_put_page(page);
|
|
|
|
return err;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Set the first fragment of directory.
|
|
|
|
*/
|
|
|
|
int nilfs_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 = nilfs_chunk_size(inode);
|
|
|
|
struct nilfs_dir_entry *de;
|
|
|
|
int err;
|
|
|
|
void *kaddr;
|
|
|
|
|
|
|
|
if (!page)
|
|
|
|
return -ENOMEM;
|
|
|
|
|
|
|
|
err = nilfs_prepare_chunk(page, mapping, 0, chunk_size);
|
|
|
|
if (unlikely(err)) {
|
|
|
|
unlock_page(page);
|
|
|
|
goto fail;
|
|
|
|
}
|
|
|
|
kaddr = kmap_atomic(page, KM_USER0);
|
|
|
|
memset(kaddr, 0, chunk_size);
|
|
|
|
de = (struct nilfs_dir_entry *)kaddr;
|
|
|
|
de->name_len = 1;
|
|
|
|
de->rec_len = cpu_to_le16(NILFS_DIR_REC_LEN(1));
|
|
|
|
memcpy(de->name, ".\0\0", 4);
|
|
|
|
de->inode = cpu_to_le64(inode->i_ino);
|
|
|
|
nilfs_set_de_type(de, inode);
|
|
|
|
|
|
|
|
de = (struct nilfs_dir_entry *)(kaddr + NILFS_DIR_REC_LEN(1));
|
|
|
|
de->name_len = 2;
|
|
|
|
de->rec_len = cpu_to_le16(chunk_size - NILFS_DIR_REC_LEN(1));
|
|
|
|
de->inode = cpu_to_le64(parent->i_ino);
|
|
|
|
memcpy(de->name, "..\0", 4);
|
|
|
|
nilfs_set_de_type(de, inode);
|
|
|
|
kunmap_atomic(kaddr, KM_USER0);
|
2009-11-27 18:41:11 +08:00
|
|
|
nilfs_commit_chunk(page, mapping, 0, chunk_size);
|
2009-04-07 10:01:34 +08:00
|
|
|
fail:
|
|
|
|
page_cache_release(page);
|
|
|
|
return err;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* routine to check that the specified directory is empty (for rmdir)
|
|
|
|
*/
|
|
|
|
int nilfs_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 nilfs_dir_entry *de;
|
|
|
|
|
|
|
|
page = nilfs_get_page(inode, i);
|
|
|
|
if (IS_ERR(page))
|
|
|
|
continue;
|
|
|
|
|
|
|
|
kaddr = page_address(page);
|
|
|
|
de = (struct nilfs_dir_entry *)kaddr;
|
|
|
|
kaddr += nilfs_last_byte(inode, i) - NILFS_DIR_REC_LEN(1);
|
|
|
|
|
|
|
|
while ((char *)de <= kaddr) {
|
|
|
|
if (de->rec_len == 0) {
|
|
|
|
nilfs_error(inode->i_sb, __func__,
|
|
|
|
"zero-length directory entry "
|
|
|
|
"(kaddr=%p, de=%p)\n", kaddr, de);
|
|
|
|
goto not_empty;
|
|
|
|
}
|
|
|
|
if (de->inode != 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 (de->inode !=
|
|
|
|
cpu_to_le64(inode->i_ino))
|
|
|
|
goto not_empty;
|
|
|
|
} else if (de->name[1] != '.')
|
|
|
|
goto not_empty;
|
|
|
|
}
|
|
|
|
de = nilfs_next_entry(de);
|
|
|
|
}
|
|
|
|
nilfs_put_page(page);
|
|
|
|
}
|
|
|
|
return 1;
|
|
|
|
|
|
|
|
not_empty:
|
|
|
|
nilfs_put_page(page);
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2009-10-02 06:43:56 +08:00
|
|
|
const struct file_operations nilfs_dir_operations = {
|
2009-04-07 10:01:34 +08:00
|
|
|
.llseek = generic_file_llseek,
|
|
|
|
.read = generic_read_dir,
|
|
|
|
.readdir = nilfs_readdir,
|
2009-04-07 10:01:53 +08:00
|
|
|
.unlocked_ioctl = nilfs_ioctl,
|
2009-04-07 10:01:34 +08:00
|
|
|
#ifdef CONFIG_COMPAT
|
2009-04-07 10:01:53 +08:00
|
|
|
.compat_ioctl = nilfs_ioctl,
|
2009-04-07 10:01:34 +08:00
|
|
|
#endif /* CONFIG_COMPAT */
|
|
|
|
.fsync = nilfs_sync_file,
|
|
|
|
|
|
|
|
};
|