/*
|
/*
|
* linux/fs/ext2/dir.c
|
* linux/fs/ext2/dir.c
|
*
|
*
|
* Copyright (C) 1992, 1993, 1994, 1995
|
* Copyright (C) 1992, 1993, 1994, 1995
|
* Remy Card (card@masi.ibp.fr)
|
* Remy Card (card@masi.ibp.fr)
|
* Laboratoire MASI - Institut Blaise Pascal
|
* Laboratoire MASI - Institut Blaise Pascal
|
* Universite Pierre et Marie Curie (Paris VI)
|
* Universite Pierre et Marie Curie (Paris VI)
|
*
|
*
|
* from
|
* from
|
*
|
*
|
* linux/fs/minix/dir.c
|
* linux/fs/minix/dir.c
|
*
|
*
|
* Copyright (C) 1991, 1992 Linus Torvalds
|
* Copyright (C) 1991, 1992 Linus Torvalds
|
*
|
*
|
* ext2 directory handling functions
|
* ext2 directory handling functions
|
*
|
*
|
* Big-endian to little-endian byte-swapping/bitmaps by
|
* Big-endian to little-endian byte-swapping/bitmaps by
|
* David S. Miller (davem@caip.rutgers.edu), 1995
|
* David S. Miller (davem@caip.rutgers.edu), 1995
|
*
|
*
|
* All code that works with directory layout had been switched to pagecache
|
* All code that works with directory layout had been switched to pagecache
|
* and moved here. AV
|
* and moved here. AV
|
*/
|
*/
|
|
|
#include <linux/fs.h>
|
#include <linux/fs.h>
|
#include <linux/ext2_fs.h>
|
#include <linux/ext2_fs.h>
|
#include <linux/pagemap.h>
|
#include <linux/pagemap.h>
|
|
|
typedef struct ext2_dir_entry_2 ext2_dirent;
|
typedef struct ext2_dir_entry_2 ext2_dirent;
|
|
|
/*
|
/*
|
* ext2 uses block-sized chunks. Arguably, sector-sized ones would be
|
* ext2 uses block-sized chunks. Arguably, sector-sized ones would be
|
* more robust, but we have what we have
|
* more robust, but we have what we have
|
*/
|
*/
|
static inline unsigned ext2_chunk_size(struct inode *inode)
|
static inline unsigned ext2_chunk_size(struct inode *inode)
|
{
|
{
|
return inode->i_sb->s_blocksize;
|
return inode->i_sb->s_blocksize;
|
}
|
}
|
|
|
static inline void ext2_put_page(struct page *page)
|
static inline void ext2_put_page(struct page *page)
|
{
|
{
|
kunmap(page);
|
kunmap(page);
|
page_cache_release(page);
|
page_cache_release(page);
|
}
|
}
|
|
|
static inline unsigned long dir_pages(struct inode *inode)
|
static inline unsigned long dir_pages(struct inode *inode)
|
{
|
{
|
return (inode->i_size+PAGE_CACHE_SIZE-1)>>PAGE_CACHE_SHIFT;
|
return (inode->i_size+PAGE_CACHE_SIZE-1)>>PAGE_CACHE_SHIFT;
|
}
|
}
|
|
|
static int ext2_commit_chunk(struct page *page, unsigned from, unsigned to)
|
static int ext2_commit_chunk(struct page *page, unsigned from, unsigned to)
|
{
|
{
|
struct inode *dir = page->mapping->host;
|
struct inode *dir = page->mapping->host;
|
int err = 0;
|
int err = 0;
|
dir->i_version = ++event;
|
dir->i_version = ++event;
|
page->mapping->a_ops->commit_write(NULL, page, from, to);
|
page->mapping->a_ops->commit_write(NULL, page, from, to);
|
if (IS_SYNC(dir)) {
|
if (IS_SYNC(dir)) {
|
int err2;
|
int err2;
|
err = writeout_one_page(page);
|
err = writeout_one_page(page);
|
err2 = waitfor_one_page(page);
|
err2 = waitfor_one_page(page);
|
if (err == 0)
|
if (err == 0)
|
err = err2;
|
err = err2;
|
}
|
}
|
return err;
|
return err;
|
}
|
}
|
|
|
static void ext2_check_page(struct page *page)
|
static void ext2_check_page(struct page *page)
|
{
|
{
|
struct inode *dir = page->mapping->host;
|
struct inode *dir = page->mapping->host;
|
struct super_block *sb = dir->i_sb;
|
struct super_block *sb = dir->i_sb;
|
unsigned chunk_size = ext2_chunk_size(dir);
|
unsigned chunk_size = ext2_chunk_size(dir);
|
char *kaddr = page_address(page);
|
char *kaddr = page_address(page);
|
u32 max_inumber = le32_to_cpu(sb->u.ext2_sb.s_es->s_inodes_count);
|
u32 max_inumber = le32_to_cpu(sb->u.ext2_sb.s_es->s_inodes_count);
|
unsigned offs, rec_len;
|
unsigned offs, rec_len;
|
unsigned limit = PAGE_CACHE_SIZE;
|
unsigned limit = PAGE_CACHE_SIZE;
|
ext2_dirent *p;
|
ext2_dirent *p;
|
char *error;
|
char *error;
|
|
|
if ((dir->i_size >> PAGE_CACHE_SHIFT) == page->index) {
|
if ((dir->i_size >> PAGE_CACHE_SHIFT) == page->index) {
|
limit = dir->i_size & ~PAGE_CACHE_MASK;
|
limit = dir->i_size & ~PAGE_CACHE_MASK;
|
if (limit & (chunk_size - 1))
|
if (limit & (chunk_size - 1))
|
goto Ebadsize;
|
goto Ebadsize;
|
for (offs = limit; offs<PAGE_CACHE_SIZE; offs += chunk_size) {
|
for (offs = limit; offs<PAGE_CACHE_SIZE; offs += chunk_size) {
|
ext2_dirent *p = (ext2_dirent*)(kaddr + offs);
|
ext2_dirent *p = (ext2_dirent*)(kaddr + offs);
|
p->rec_len = cpu_to_le16(chunk_size);
|
p->rec_len = cpu_to_le16(chunk_size);
|
}
|
}
|
if (!limit)
|
if (!limit)
|
goto out;
|
goto out;
|
}
|
}
|
for (offs = 0; offs <= limit - EXT2_DIR_REC_LEN(1); offs += rec_len) {
|
for (offs = 0; offs <= limit - EXT2_DIR_REC_LEN(1); offs += rec_len) {
|
p = (ext2_dirent *)(kaddr + offs);
|
p = (ext2_dirent *)(kaddr + offs);
|
rec_len = le16_to_cpu(p->rec_len);
|
rec_len = le16_to_cpu(p->rec_len);
|
|
|
if (rec_len < EXT2_DIR_REC_LEN(1))
|
if (rec_len < EXT2_DIR_REC_LEN(1))
|
goto Eshort;
|
goto Eshort;
|
if (rec_len & 3)
|
if (rec_len & 3)
|
goto Ealign;
|
goto Ealign;
|
if (rec_len < EXT2_DIR_REC_LEN(p->name_len))
|
if (rec_len < EXT2_DIR_REC_LEN(p->name_len))
|
goto Enamelen;
|
goto Enamelen;
|
if (((offs + rec_len - 1) ^ offs) & ~(chunk_size-1))
|
if (((offs + rec_len - 1) ^ offs) & ~(chunk_size-1))
|
goto Espan;
|
goto Espan;
|
if (le32_to_cpu(p->inode) > max_inumber)
|
if (le32_to_cpu(p->inode) > max_inumber)
|
goto Einumber;
|
goto Einumber;
|
}
|
}
|
if (offs != limit)
|
if (offs != limit)
|
goto Eend;
|
goto Eend;
|
out:
|
out:
|
SetPageChecked(page);
|
SetPageChecked(page);
|
return;
|
return;
|
|
|
/* Too bad, we had an error */
|
/* Too bad, we had an error */
|
|
|
Ebadsize:
|
Ebadsize:
|
ext2_error(sb, "ext2_check_page",
|
ext2_error(sb, "ext2_check_page",
|
"size of directory #%lu is not a multiple of chunk size",
|
"size of directory #%lu is not a multiple of chunk size",
|
dir->i_ino
|
dir->i_ino
|
);
|
);
|
goto fail;
|
goto fail;
|
Eshort:
|
Eshort:
|
error = "rec_len is smaller than minimal";
|
error = "rec_len is smaller than minimal";
|
goto bad_entry;
|
goto bad_entry;
|
Ealign:
|
Ealign:
|
error = "unaligned directory entry";
|
error = "unaligned directory entry";
|
goto bad_entry;
|
goto bad_entry;
|
Enamelen:
|
Enamelen:
|
error = "rec_len is too small for name_len";
|
error = "rec_len is too small for name_len";
|
goto bad_entry;
|
goto bad_entry;
|
Espan:
|
Espan:
|
error = "directory entry across blocks";
|
error = "directory entry across blocks";
|
goto bad_entry;
|
goto bad_entry;
|
Einumber:
|
Einumber:
|
error = "inode out of bounds";
|
error = "inode out of bounds";
|
bad_entry:
|
bad_entry:
|
ext2_error (sb, "ext2_check_page", "bad entry in directory #%lu: %s - "
|
ext2_error (sb, "ext2_check_page", "bad entry in directory #%lu: %s - "
|
"offset=%lu, inode=%lu, rec_len=%d, name_len=%d",
|
"offset=%lu, inode=%lu, rec_len=%d, name_len=%d",
|
dir->i_ino, error, (page->index<<PAGE_CACHE_SHIFT)+offs,
|
dir->i_ino, error, (page->index<<PAGE_CACHE_SHIFT)+offs,
|
(unsigned long) le32_to_cpu(p->inode),
|
(unsigned long) le32_to_cpu(p->inode),
|
rec_len, p->name_len);
|
rec_len, p->name_len);
|
goto fail;
|
goto fail;
|
Eend:
|
Eend:
|
p = (ext2_dirent *)(kaddr + offs);
|
p = (ext2_dirent *)(kaddr + offs);
|
ext2_error (sb, "ext2_check_page",
|
ext2_error (sb, "ext2_check_page",
|
"entry in directory #%lu spans the page boundary"
|
"entry in directory #%lu spans the page boundary"
|
"offset=%lu, inode=%lu",
|
"offset=%lu, inode=%lu",
|
dir->i_ino, (page->index<<PAGE_CACHE_SHIFT)+offs,
|
dir->i_ino, (page->index<<PAGE_CACHE_SHIFT)+offs,
|
(unsigned long) le32_to_cpu(p->inode));
|
(unsigned long) le32_to_cpu(p->inode));
|
fail:
|
fail:
|
SetPageChecked(page);
|
SetPageChecked(page);
|
SetPageError(page);
|
SetPageError(page);
|
}
|
}
|
|
|
static struct page * ext2_get_page(struct inode *dir, unsigned long n)
|
static struct page * ext2_get_page(struct inode *dir, unsigned long n)
|
{
|
{
|
struct address_space *mapping = dir->i_mapping;
|
struct address_space *mapping = dir->i_mapping;
|
struct page *page = read_cache_page(mapping, n,
|
struct page *page = read_cache_page(mapping, n,
|
(filler_t*)mapping->a_ops->readpage, NULL);
|
(filler_t*)mapping->a_ops->readpage, NULL);
|
if (!IS_ERR(page)) {
|
if (!IS_ERR(page)) {
|
wait_on_page(page);
|
wait_on_page(page);
|
kmap(page);
|
kmap(page);
|
if (!Page_Uptodate(page))
|
if (!Page_Uptodate(page))
|
goto fail;
|
goto fail;
|
if (!PageChecked(page))
|
if (!PageChecked(page))
|
ext2_check_page(page);
|
ext2_check_page(page);
|
if (PageError(page))
|
if (PageError(page))
|
goto fail;
|
goto fail;
|
}
|
}
|
return page;
|
return page;
|
|
|
fail:
|
fail:
|
ext2_put_page(page);
|
ext2_put_page(page);
|
return ERR_PTR(-EIO);
|
return ERR_PTR(-EIO);
|
}
|
}
|
|
|
/*
|
/*
|
* NOTE! unlike strncmp, ext2_match returns 1 for success, 0 for failure.
|
* NOTE! unlike strncmp, ext2_match returns 1 for success, 0 for failure.
|
*
|
*
|
* len <= EXT2_NAME_LEN and de != NULL are guaranteed by caller.
|
* len <= EXT2_NAME_LEN and de != NULL are guaranteed by caller.
|
*/
|
*/
|
static inline int ext2_match (int len, const char * const name,
|
static inline int ext2_match (int len, const char * const name,
|
struct ext2_dir_entry_2 * de)
|
struct ext2_dir_entry_2 * de)
|
{
|
{
|
if (len != de->name_len)
|
if (len != de->name_len)
|
return 0;
|
return 0;
|
if (!de->inode)
|
if (!de->inode)
|
return 0;
|
return 0;
|
return !memcmp(name, de->name, len);
|
return !memcmp(name, de->name, len);
|
}
|
}
|
|
|
/*
|
/*
|
* p is at least 6 bytes before the end of page
|
* p is at least 6 bytes before the end of page
|
*/
|
*/
|
static inline ext2_dirent *ext2_next_entry(ext2_dirent *p)
|
static inline ext2_dirent *ext2_next_entry(ext2_dirent *p)
|
{
|
{
|
return (ext2_dirent *)((char*)p + le16_to_cpu(p->rec_len));
|
return (ext2_dirent *)((char*)p + le16_to_cpu(p->rec_len));
|
}
|
}
|
|
|
static inline unsigned
|
static inline unsigned
|
ext2_validate_entry(char *base, unsigned offset, unsigned mask)
|
ext2_validate_entry(char *base, unsigned offset, unsigned mask)
|
{
|
{
|
ext2_dirent *de = (ext2_dirent*)(base + offset);
|
ext2_dirent *de = (ext2_dirent*)(base + offset);
|
ext2_dirent *p = (ext2_dirent*)(base + (offset&mask));
|
ext2_dirent *p = (ext2_dirent*)(base + (offset&mask));
|
while ((char*)p < (char*)de)
|
while ((char*)p < (char*)de)
|
p = ext2_next_entry(p);
|
p = ext2_next_entry(p);
|
return (char *)p - base;
|
return (char *)p - base;
|
}
|
}
|
|
|
static unsigned char ext2_filetype_table[EXT2_FT_MAX] = {
|
static unsigned char ext2_filetype_table[EXT2_FT_MAX] = {
|
[EXT2_FT_UNKNOWN] DT_UNKNOWN,
|
[EXT2_FT_UNKNOWN] DT_UNKNOWN,
|
[EXT2_FT_REG_FILE] DT_REG,
|
[EXT2_FT_REG_FILE] DT_REG,
|
[EXT2_FT_DIR] DT_DIR,
|
[EXT2_FT_DIR] DT_DIR,
|
[EXT2_FT_CHRDEV] DT_CHR,
|
[EXT2_FT_CHRDEV] DT_CHR,
|
[EXT2_FT_BLKDEV] DT_BLK,
|
[EXT2_FT_BLKDEV] DT_BLK,
|
[EXT2_FT_FIFO] DT_FIFO,
|
[EXT2_FT_FIFO] DT_FIFO,
|
[EXT2_FT_SOCK] DT_SOCK,
|
[EXT2_FT_SOCK] DT_SOCK,
|
[EXT2_FT_SYMLINK] DT_LNK,
|
[EXT2_FT_SYMLINK] DT_LNK,
|
};
|
};
|
|
|
#define S_SHIFT 12
|
#define S_SHIFT 12
|
static unsigned char ext2_type_by_mode[S_IFMT >> S_SHIFT] = {
|
static unsigned char ext2_type_by_mode[S_IFMT >> S_SHIFT] = {
|
[S_IFREG >> S_SHIFT] EXT2_FT_REG_FILE,
|
[S_IFREG >> S_SHIFT] EXT2_FT_REG_FILE,
|
[S_IFDIR >> S_SHIFT] EXT2_FT_DIR,
|
[S_IFDIR >> S_SHIFT] EXT2_FT_DIR,
|
[S_IFCHR >> S_SHIFT] EXT2_FT_CHRDEV,
|
[S_IFCHR >> S_SHIFT] EXT2_FT_CHRDEV,
|
[S_IFBLK >> S_SHIFT] EXT2_FT_BLKDEV,
|
[S_IFBLK >> S_SHIFT] EXT2_FT_BLKDEV,
|
[S_IFIFO >> S_SHIFT] EXT2_FT_FIFO,
|
[S_IFIFO >> S_SHIFT] EXT2_FT_FIFO,
|
[S_IFSOCK >> S_SHIFT] EXT2_FT_SOCK,
|
[S_IFSOCK >> S_SHIFT] EXT2_FT_SOCK,
|
[S_IFLNK >> S_SHIFT] EXT2_FT_SYMLINK,
|
[S_IFLNK >> S_SHIFT] EXT2_FT_SYMLINK,
|
};
|
};
|
|
|
static inline void ext2_set_de_type(ext2_dirent *de, struct inode *inode)
|
static inline void ext2_set_de_type(ext2_dirent *de, struct inode *inode)
|
{
|
{
|
mode_t mode = inode->i_mode;
|
mode_t mode = inode->i_mode;
|
if (EXT2_HAS_INCOMPAT_FEATURE(inode->i_sb, EXT2_FEATURE_INCOMPAT_FILETYPE))
|
if (EXT2_HAS_INCOMPAT_FEATURE(inode->i_sb, EXT2_FEATURE_INCOMPAT_FILETYPE))
|
de->file_type = ext2_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
|
de->file_type = ext2_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
|
else
|
else
|
de->file_type = 0;
|
de->file_type = 0;
|
}
|
}
|
|
|
static int
|
static int
|
ext2_readdir (struct file * filp, void * dirent, filldir_t filldir)
|
ext2_readdir (struct file * filp, void * dirent, filldir_t filldir)
|
{
|
{
|
loff_t pos = filp->f_pos;
|
loff_t pos = filp->f_pos;
|
struct inode *inode = filp->f_dentry->d_inode;
|
struct inode *inode = filp->f_dentry->d_inode;
|
struct super_block *sb = inode->i_sb;
|
struct super_block *sb = inode->i_sb;
|
unsigned offset = pos & ~PAGE_CACHE_MASK;
|
unsigned offset = pos & ~PAGE_CACHE_MASK;
|
unsigned long n = pos >> PAGE_CACHE_SHIFT;
|
unsigned long n = pos >> PAGE_CACHE_SHIFT;
|
unsigned long npages = dir_pages(inode);
|
unsigned long npages = dir_pages(inode);
|
unsigned chunk_mask = ~(ext2_chunk_size(inode)-1);
|
unsigned chunk_mask = ~(ext2_chunk_size(inode)-1);
|
unsigned char *types = NULL;
|
unsigned char *types = NULL;
|
int need_revalidate = (filp->f_version != inode->i_version);
|
int need_revalidate = (filp->f_version != inode->i_version);
|
|
|
if (pos > inode->i_size - EXT2_DIR_REC_LEN(1))
|
if (pos > inode->i_size - EXT2_DIR_REC_LEN(1))
|
goto done;
|
goto done;
|
|
|
if (EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_FILETYPE))
|
if (EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_FILETYPE))
|
types = ext2_filetype_table;
|
types = ext2_filetype_table;
|
|
|
for ( ; n < npages; n++, offset = 0) {
|
for ( ; n < npages; n++, offset = 0) {
|
char *kaddr, *limit;
|
char *kaddr, *limit;
|
ext2_dirent *de;
|
ext2_dirent *de;
|
struct page *page = ext2_get_page(inode, n);
|
struct page *page = ext2_get_page(inode, n);
|
|
|
if (IS_ERR(page))
|
if (IS_ERR(page))
|
continue;
|
continue;
|
kaddr = page_address(page);
|
kaddr = page_address(page);
|
if (need_revalidate) {
|
if (need_revalidate) {
|
offset = ext2_validate_entry(kaddr, offset, chunk_mask);
|
offset = ext2_validate_entry(kaddr, offset, chunk_mask);
|
need_revalidate = 0;
|
need_revalidate = 0;
|
}
|
}
|
de = (ext2_dirent *)(kaddr+offset);
|
de = (ext2_dirent *)(kaddr+offset);
|
limit = kaddr + PAGE_CACHE_SIZE - EXT2_DIR_REC_LEN(1);
|
limit = kaddr + PAGE_CACHE_SIZE - EXT2_DIR_REC_LEN(1);
|
for ( ;(char*)de <= limit; de = ext2_next_entry(de))
|
for ( ;(char*)de <= limit; de = ext2_next_entry(de))
|
if (de->inode) {
|
if (de->inode) {
|
int over;
|
int over;
|
unsigned char d_type = DT_UNKNOWN;
|
unsigned char d_type = DT_UNKNOWN;
|
|
|
if (types && de->file_type < EXT2_FT_MAX)
|
if (types && de->file_type < EXT2_FT_MAX)
|
d_type = types[de->file_type];
|
d_type = types[de->file_type];
|
|
|
offset = (char *)de - kaddr;
|
offset = (char *)de - kaddr;
|
over = filldir(dirent, de->name, de->name_len,
|
over = filldir(dirent, de->name, de->name_len,
|
(n<<PAGE_CACHE_SHIFT) | offset,
|
(n<<PAGE_CACHE_SHIFT) | offset,
|
le32_to_cpu(de->inode), d_type);
|
le32_to_cpu(de->inode), d_type);
|
if (over) {
|
if (over) {
|
ext2_put_page(page);
|
ext2_put_page(page);
|
goto done;
|
goto done;
|
}
|
}
|
}
|
}
|
ext2_put_page(page);
|
ext2_put_page(page);
|
}
|
}
|
|
|
done:
|
done:
|
filp->f_pos = (n << PAGE_CACHE_SHIFT) | offset;
|
filp->f_pos = (n << PAGE_CACHE_SHIFT) | offset;
|
filp->f_version = inode->i_version;
|
filp->f_version = inode->i_version;
|
UPDATE_ATIME(inode);
|
UPDATE_ATIME(inode);
|
return 0;
|
return 0;
|
}
|
}
|
|
|
/*
|
/*
|
* ext2_find_entry()
|
* ext2_find_entry()
|
*
|
*
|
* finds an entry in the specified directory with the wanted name. It
|
* 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
|
* returns the page in which the entry was found, and the entry itself
|
* (as a parameter - res_dir). Page is returned mapped and unlocked.
|
* (as a parameter - res_dir). Page is returned mapped and unlocked.
|
* Entry is guaranteed to be valid.
|
* Entry is guaranteed to be valid.
|
*/
|
*/
|
struct ext2_dir_entry_2 * ext2_find_entry (struct inode * dir,
|
struct ext2_dir_entry_2 * ext2_find_entry (struct inode * dir,
|
struct dentry *dentry, struct page ** res_page)
|
struct dentry *dentry, struct page ** res_page)
|
{
|
{
|
const char *name = dentry->d_name.name;
|
const char *name = dentry->d_name.name;
|
int namelen = dentry->d_name.len;
|
int namelen = dentry->d_name.len;
|
unsigned reclen = EXT2_DIR_REC_LEN(namelen);
|
unsigned reclen = EXT2_DIR_REC_LEN(namelen);
|
unsigned long start, n;
|
unsigned long start, n;
|
unsigned long npages = dir_pages(dir);
|
unsigned long npages = dir_pages(dir);
|
struct page *page = NULL;
|
struct page *page = NULL;
|
ext2_dirent * de;
|
ext2_dirent * de;
|
|
|
/* OFFSET_CACHE */
|
/* OFFSET_CACHE */
|
*res_page = NULL;
|
*res_page = NULL;
|
|
|
start = dir->u.ext2_i.i_dir_start_lookup;
|
start = dir->u.ext2_i.i_dir_start_lookup;
|
if (start >= npages)
|
if (start >= npages)
|
start = 0;
|
start = 0;
|
n = start;
|
n = start;
|
do {
|
do {
|
char *kaddr;
|
char *kaddr;
|
page = ext2_get_page(dir, n);
|
page = ext2_get_page(dir, n);
|
if (!IS_ERR(page)) {
|
if (!IS_ERR(page)) {
|
kaddr = page_address(page);
|
kaddr = page_address(page);
|
de = (ext2_dirent *) kaddr;
|
de = (ext2_dirent *) kaddr;
|
kaddr += PAGE_CACHE_SIZE - reclen;
|
kaddr += PAGE_CACHE_SIZE - reclen;
|
while ((char *) de <= kaddr) {
|
while ((char *) de <= kaddr) {
|
if (ext2_match (namelen, name, de))
|
if (ext2_match (namelen, name, de))
|
goto found;
|
goto found;
|
de = ext2_next_entry(de);
|
de = ext2_next_entry(de);
|
}
|
}
|
ext2_put_page(page);
|
ext2_put_page(page);
|
}
|
}
|
if (++n >= npages)
|
if (++n >= npages)
|
n = 0;
|
n = 0;
|
} while (n != start);
|
} while (n != start);
|
return NULL;
|
return NULL;
|
|
|
found:
|
found:
|
*res_page = page;
|
*res_page = page;
|
dir->u.ext2_i.i_dir_start_lookup = n;
|
dir->u.ext2_i.i_dir_start_lookup = n;
|
return de;
|
return de;
|
}
|
}
|
|
|
struct ext2_dir_entry_2 * ext2_dotdot (struct inode *dir, struct page **p)
|
struct ext2_dir_entry_2 * ext2_dotdot (struct inode *dir, struct page **p)
|
{
|
{
|
struct page *page = ext2_get_page(dir, 0);
|
struct page *page = ext2_get_page(dir, 0);
|
ext2_dirent *de = NULL;
|
ext2_dirent *de = NULL;
|
|
|
if (!IS_ERR(page)) {
|
if (!IS_ERR(page)) {
|
de = ext2_next_entry((ext2_dirent *) page_address(page));
|
de = ext2_next_entry((ext2_dirent *) page_address(page));
|
*p = page;
|
*p = page;
|
}
|
}
|
return de;
|
return de;
|
}
|
}
|
|
|
ino_t ext2_inode_by_name(struct inode * dir, struct dentry *dentry)
|
ino_t ext2_inode_by_name(struct inode * dir, struct dentry *dentry)
|
{
|
{
|
ino_t res = 0;
|
ino_t res = 0;
|
struct ext2_dir_entry_2 * de;
|
struct ext2_dir_entry_2 * de;
|
struct page *page;
|
struct page *page;
|
|
|
de = ext2_find_entry (dir, dentry, &page);
|
de = ext2_find_entry (dir, dentry, &page);
|
if (de) {
|
if (de) {
|
res = le32_to_cpu(de->inode);
|
res = le32_to_cpu(de->inode);
|
kunmap(page);
|
kunmap(page);
|
page_cache_release(page);
|
page_cache_release(page);
|
}
|
}
|
return res;
|
return res;
|
}
|
}
|
|
|
/* Releases the page */
|
/* Releases the page */
|
void ext2_set_link(struct inode *dir, struct ext2_dir_entry_2 *de,
|
void ext2_set_link(struct inode *dir, struct ext2_dir_entry_2 *de,
|
struct page *page, struct inode *inode)
|
struct page *page, struct inode *inode)
|
{
|
{
|
unsigned from = (char *) de - (char *) page_address(page);
|
unsigned from = (char *) de - (char *) page_address(page);
|
unsigned to = from + le16_to_cpu(de->rec_len);
|
unsigned to = from + le16_to_cpu(de->rec_len);
|
int err;
|
int err;
|
|
|
lock_page(page);
|
lock_page(page);
|
err = page->mapping->a_ops->prepare_write(NULL, page, from, to);
|
err = page->mapping->a_ops->prepare_write(NULL, page, from, to);
|
if (err)
|
if (err)
|
BUG();
|
BUG();
|
de->inode = cpu_to_le32(inode->i_ino);
|
de->inode = cpu_to_le32(inode->i_ino);
|
ext2_set_de_type (de, inode);
|
ext2_set_de_type (de, inode);
|
err = ext2_commit_chunk(page, from, to);
|
err = ext2_commit_chunk(page, from, to);
|
UnlockPage(page);
|
UnlockPage(page);
|
ext2_put_page(page);
|
ext2_put_page(page);
|
dir->i_mtime = dir->i_ctime = CURRENT_TIME;
|
dir->i_mtime = dir->i_ctime = CURRENT_TIME;
|
dir->u.ext2_i.i_flags &= ~EXT2_BTREE_FL;
|
dir->u.ext2_i.i_flags &= ~EXT2_BTREE_FL;
|
mark_inode_dirty(dir);
|
mark_inode_dirty(dir);
|
}
|
}
|
|
|
/*
|
/*
|
* Parent is locked.
|
* Parent is locked.
|
*/
|
*/
|
int ext2_add_link (struct dentry *dentry, struct inode *inode)
|
int ext2_add_link (struct dentry *dentry, struct inode *inode)
|
{
|
{
|
struct inode *dir = dentry->d_parent->d_inode;
|
struct inode *dir = dentry->d_parent->d_inode;
|
const char *name = dentry->d_name.name;
|
const char *name = dentry->d_name.name;
|
int namelen = dentry->d_name.len;
|
int namelen = dentry->d_name.len;
|
unsigned reclen = EXT2_DIR_REC_LEN(namelen);
|
unsigned reclen = EXT2_DIR_REC_LEN(namelen);
|
unsigned short rec_len, name_len;
|
unsigned short rec_len, name_len;
|
struct page *page = NULL;
|
struct page *page = NULL;
|
ext2_dirent * de;
|
ext2_dirent * de;
|
unsigned long npages = dir_pages(dir);
|
unsigned long npages = dir_pages(dir);
|
unsigned long n;
|
unsigned long n;
|
char *kaddr;
|
char *kaddr;
|
unsigned from, to;
|
unsigned from, to;
|
int err;
|
int err;
|
|
|
/* We take care of directory expansion in the same loop */
|
/* We take care of directory expansion in the same loop */
|
for (n = 0; n <= npages; n++) {
|
for (n = 0; n <= npages; n++) {
|
page = ext2_get_page(dir, n);
|
page = ext2_get_page(dir, n);
|
err = PTR_ERR(page);
|
err = PTR_ERR(page);
|
if (IS_ERR(page))
|
if (IS_ERR(page))
|
goto out;
|
goto out;
|
kaddr = page_address(page);
|
kaddr = page_address(page);
|
de = (ext2_dirent *)kaddr;
|
de = (ext2_dirent *)kaddr;
|
kaddr += PAGE_CACHE_SIZE - reclen;
|
kaddr += PAGE_CACHE_SIZE - reclen;
|
while ((char *)de <= kaddr) {
|
while ((char *)de <= kaddr) {
|
err = -EEXIST;
|
err = -EEXIST;
|
if (ext2_match (namelen, name, de))
|
if (ext2_match (namelen, name, de))
|
goto out_page;
|
goto out_page;
|
name_len = EXT2_DIR_REC_LEN(de->name_len);
|
name_len = EXT2_DIR_REC_LEN(de->name_len);
|
rec_len = le16_to_cpu(de->rec_len);
|
rec_len = le16_to_cpu(de->rec_len);
|
if (!de->inode && rec_len >= reclen)
|
if (!de->inode && rec_len >= reclen)
|
goto got_it;
|
goto got_it;
|
if (rec_len >= name_len + reclen)
|
if (rec_len >= name_len + reclen)
|
goto got_it;
|
goto got_it;
|
de = (ext2_dirent *) ((char *) de + rec_len);
|
de = (ext2_dirent *) ((char *) de + rec_len);
|
}
|
}
|
ext2_put_page(page);
|
ext2_put_page(page);
|
}
|
}
|
BUG();
|
BUG();
|
return -EINVAL;
|
return -EINVAL;
|
|
|
got_it:
|
got_it:
|
from = (char*)de - (char*)page_address(page);
|
from = (char*)de - (char*)page_address(page);
|
to = from + rec_len;
|
to = from + rec_len;
|
lock_page(page);
|
lock_page(page);
|
err = page->mapping->a_ops->prepare_write(NULL, page, from, to);
|
err = page->mapping->a_ops->prepare_write(NULL, page, from, to);
|
if (err)
|
if (err)
|
goto out_unlock;
|
goto out_unlock;
|
if (de->inode) {
|
if (de->inode) {
|
ext2_dirent *de1 = (ext2_dirent *) ((char *) de + name_len);
|
ext2_dirent *de1 = (ext2_dirent *) ((char *) de + name_len);
|
de1->rec_len = cpu_to_le16(rec_len - name_len);
|
de1->rec_len = cpu_to_le16(rec_len - name_len);
|
de->rec_len = cpu_to_le16(name_len);
|
de->rec_len = cpu_to_le16(name_len);
|
de = de1;
|
de = de1;
|
}
|
}
|
de->name_len = namelen;
|
de->name_len = namelen;
|
memcpy (de->name, name, namelen);
|
memcpy (de->name, name, namelen);
|
de->inode = cpu_to_le32(inode->i_ino);
|
de->inode = cpu_to_le32(inode->i_ino);
|
ext2_set_de_type (de, inode);
|
ext2_set_de_type (de, inode);
|
err = ext2_commit_chunk(page, from, to);
|
err = ext2_commit_chunk(page, from, to);
|
dir->i_mtime = dir->i_ctime = CURRENT_TIME;
|
dir->i_mtime = dir->i_ctime = CURRENT_TIME;
|
dir->u.ext2_i.i_flags &= ~EXT2_BTREE_FL;
|
dir->u.ext2_i.i_flags &= ~EXT2_BTREE_FL;
|
mark_inode_dirty(dir);
|
mark_inode_dirty(dir);
|
/* OFFSET_CACHE */
|
/* OFFSET_CACHE */
|
out_unlock:
|
out_unlock:
|
UnlockPage(page);
|
UnlockPage(page);
|
out_page:
|
out_page:
|
ext2_put_page(page);
|
ext2_put_page(page);
|
out:
|
out:
|
return err;
|
return err;
|
}
|
}
|
|
|
/*
|
/*
|
* ext2_delete_entry deletes a directory entry by merging it with the
|
* ext2_delete_entry deletes a directory entry by merging it with the
|
* previous entry. Page is up-to-date. Releases the page.
|
* previous entry. Page is up-to-date. Releases the page.
|
*/
|
*/
|
int ext2_delete_entry (struct ext2_dir_entry_2 * dir, struct page * page )
|
int ext2_delete_entry (struct ext2_dir_entry_2 * dir, struct page * page )
|
{
|
{
|
struct address_space *mapping = page->mapping;
|
struct address_space *mapping = page->mapping;
|
struct inode *inode = mapping->host;
|
struct inode *inode = mapping->host;
|
char *kaddr = page_address(page);
|
char *kaddr = page_address(page);
|
unsigned from = ((char*)dir - kaddr) & ~(ext2_chunk_size(inode)-1);
|
unsigned from = ((char*)dir - kaddr) & ~(ext2_chunk_size(inode)-1);
|
unsigned to = ((char*)dir - kaddr) + le16_to_cpu(dir->rec_len);
|
unsigned to = ((char*)dir - kaddr) + le16_to_cpu(dir->rec_len);
|
ext2_dirent * pde = NULL;
|
ext2_dirent * pde = NULL;
|
ext2_dirent * de = (ext2_dirent *) (kaddr + from);
|
ext2_dirent * de = (ext2_dirent *) (kaddr + from);
|
int err;
|
int err;
|
|
|
while ((char*)de < (char*)dir) {
|
while ((char*)de < (char*)dir) {
|
pde = de;
|
pde = de;
|
de = ext2_next_entry(de);
|
de = ext2_next_entry(de);
|
}
|
}
|
if (pde)
|
if (pde)
|
from = (char*)pde - (char*)page_address(page);
|
from = (char*)pde - (char*)page_address(page);
|
lock_page(page);
|
lock_page(page);
|
err = mapping->a_ops->prepare_write(NULL, page, from, to);
|
err = mapping->a_ops->prepare_write(NULL, page, from, to);
|
if (err)
|
if (err)
|
BUG();
|
BUG();
|
if (pde)
|
if (pde)
|
pde->rec_len = cpu_to_le16(to-from);
|
pde->rec_len = cpu_to_le16(to-from);
|
dir->inode = 0;
|
dir->inode = 0;
|
err = ext2_commit_chunk(page, from, to);
|
err = ext2_commit_chunk(page, from, to);
|
UnlockPage(page);
|
UnlockPage(page);
|
ext2_put_page(page);
|
ext2_put_page(page);
|
inode->i_ctime = inode->i_mtime = CURRENT_TIME;
|
inode->i_ctime = inode->i_mtime = CURRENT_TIME;
|
inode->u.ext2_i.i_flags &= ~EXT2_BTREE_FL;
|
inode->u.ext2_i.i_flags &= ~EXT2_BTREE_FL;
|
mark_inode_dirty(inode);
|
mark_inode_dirty(inode);
|
return err;
|
return err;
|
}
|
}
|
|
|
/*
|
/*
|
* Set the first fragment of directory.
|
* Set the first fragment of directory.
|
*/
|
*/
|
int ext2_make_empty(struct inode *inode, struct inode *parent)
|
int ext2_make_empty(struct inode *inode, struct inode *parent)
|
{
|
{
|
struct address_space *mapping = inode->i_mapping;
|
struct address_space *mapping = inode->i_mapping;
|
struct page *page = grab_cache_page(mapping, 0);
|
struct page *page = grab_cache_page(mapping, 0);
|
unsigned chunk_size = ext2_chunk_size(inode);
|
unsigned chunk_size = ext2_chunk_size(inode);
|
struct ext2_dir_entry_2 * de;
|
struct ext2_dir_entry_2 * de;
|
char *base;
|
char *base;
|
int err;
|
int err;
|
|
|
if (!page)
|
if (!page)
|
return -ENOMEM;
|
return -ENOMEM;
|
err = mapping->a_ops->prepare_write(NULL, page, 0, chunk_size);
|
err = mapping->a_ops->prepare_write(NULL, page, 0, chunk_size);
|
if (err)
|
if (err)
|
goto fail;
|
goto fail;
|
|
|
base = page_address(page);
|
base = page_address(page);
|
|
|
de = (struct ext2_dir_entry_2 *) base;
|
de = (struct ext2_dir_entry_2 *) base;
|
de->name_len = 1;
|
de->name_len = 1;
|
de->rec_len = cpu_to_le16(EXT2_DIR_REC_LEN(1));
|
de->rec_len = cpu_to_le16(EXT2_DIR_REC_LEN(1));
|
memcpy (de->name, ".\0\0", 4);
|
memcpy (de->name, ".\0\0", 4);
|
de->inode = cpu_to_le32(inode->i_ino);
|
de->inode = cpu_to_le32(inode->i_ino);
|
ext2_set_de_type (de, inode);
|
ext2_set_de_type (de, inode);
|
|
|
de = (struct ext2_dir_entry_2 *) (base + EXT2_DIR_REC_LEN(1));
|
de = (struct ext2_dir_entry_2 *) (base + EXT2_DIR_REC_LEN(1));
|
de->name_len = 2;
|
de->name_len = 2;
|
de->rec_len = cpu_to_le16(chunk_size - EXT2_DIR_REC_LEN(1));
|
de->rec_len = cpu_to_le16(chunk_size - EXT2_DIR_REC_LEN(1));
|
de->inode = cpu_to_le32(parent->i_ino);
|
de->inode = cpu_to_le32(parent->i_ino);
|
memcpy (de->name, "..\0", 4);
|
memcpy (de->name, "..\0", 4);
|
ext2_set_de_type (de, inode);
|
ext2_set_de_type (de, inode);
|
|
|
err = ext2_commit_chunk(page, 0, chunk_size);
|
err = ext2_commit_chunk(page, 0, chunk_size);
|
fail:
|
fail:
|
UnlockPage(page);
|
UnlockPage(page);
|
page_cache_release(page);
|
page_cache_release(page);
|
return err;
|
return err;
|
}
|
}
|
|
|
/*
|
/*
|
* routine to check that the specified directory is empty (for rmdir)
|
* routine to check that the specified directory is empty (for rmdir)
|
*/
|
*/
|
int ext2_empty_dir (struct inode * inode)
|
int ext2_empty_dir (struct inode * inode)
|
{
|
{
|
struct page *page = NULL;
|
struct page *page = NULL;
|
unsigned long i, npages = dir_pages(inode);
|
unsigned long i, npages = dir_pages(inode);
|
|
|
for (i = 0; i < npages; i++) {
|
for (i = 0; i < npages; i++) {
|
char *kaddr;
|
char *kaddr;
|
ext2_dirent * de;
|
ext2_dirent * de;
|
page = ext2_get_page(inode, i);
|
page = ext2_get_page(inode, i);
|
|
|
if (IS_ERR(page))
|
if (IS_ERR(page))
|
continue;
|
continue;
|
|
|
kaddr = page_address(page);
|
kaddr = page_address(page);
|
de = (ext2_dirent *)kaddr;
|
de = (ext2_dirent *)kaddr;
|
kaddr += PAGE_CACHE_SIZE-EXT2_DIR_REC_LEN(1);
|
kaddr += PAGE_CACHE_SIZE-EXT2_DIR_REC_LEN(1);
|
|
|
while ((char *)de <= kaddr) {
|
while ((char *)de <= kaddr) {
|
if (de->inode != 0) {
|
if (de->inode != 0) {
|
/* check for . and .. */
|
/* check for . and .. */
|
if (de->name[0] != '.')
|
if (de->name[0] != '.')
|
goto not_empty;
|
goto not_empty;
|
if (de->name_len > 2)
|
if (de->name_len > 2)
|
goto not_empty;
|
goto not_empty;
|
if (de->name_len < 2) {
|
if (de->name_len < 2) {
|
if (de->inode !=
|
if (de->inode !=
|
cpu_to_le32(inode->i_ino))
|
cpu_to_le32(inode->i_ino))
|
goto not_empty;
|
goto not_empty;
|
} else if (de->name[1] != '.')
|
} else if (de->name[1] != '.')
|
goto not_empty;
|
goto not_empty;
|
}
|
}
|
de = ext2_next_entry(de);
|
de = ext2_next_entry(de);
|
}
|
}
|
ext2_put_page(page);
|
ext2_put_page(page);
|
}
|
}
|
return 1;
|
return 1;
|
|
|
not_empty:
|
not_empty:
|
ext2_put_page(page);
|
ext2_put_page(page);
|
return 0;
|
return 0;
|
}
|
}
|
|
|
struct file_operations ext2_dir_operations = {
|
struct file_operations ext2_dir_operations = {
|
read: generic_read_dir,
|
read: generic_read_dir,
|
readdir: ext2_readdir,
|
readdir: ext2_readdir,
|
ioctl: ext2_ioctl,
|
ioctl: ext2_ioctl,
|
fsync: ext2_sync_file,
|
fsync: ext2_sync_file,
|
};
|
};
|
|
|
