int sysv_add_link(struct dentry *dentry, struct inode *inode)
{
struct inode *dir = dentry->d_parent->d_inode;
const char * name = dentry->d_name.name;
int namelen = dentry->d_name.len;
struct page *page = NULL;
struct sysv_dir_entry * de;
unsigned long npages = dir_pages(dir);
unsigned long n;
char *kaddr;
loff_t pos;
int err;
/* We take care of directory expansion in the same loop */
for (n = 0; n <= npages; n++) {
page = dir_get_page(dir, n);
err = PTR_ERR(page);
if (IS_ERR(page))
goto out;
kaddr = (char*)page_address(page);
de = (struct sysv_dir_entry *)kaddr;
kaddr += PAGE_CACHE_SIZE - SYSV_DIRSIZE;
while ((char *)de <= kaddr) {
if (!de->inode)
goto got_it;
err = -EEXIST;
if (namecompare(namelen, SYSV_NAMELEN, name, de->name))
goto out_page;
de++;
}
dir_put_page(page);
}
BUG();
return -EINVAL;
got_it:
pos = page_offset(page) +
(char*)de - (char*)page_address(page);
lock_page(page);
err = __sysv_write_begin(NULL, page->mapping, pos, SYSV_DIRSIZE,
AOP_FLAG_UNINTERRUPTIBLE, &page, NULL);
if (err)
goto out_unlock;
memcpy (de->name, name, namelen);
memset (de->name + namelen, 0, SYSV_DIRSIZE - namelen - 2);
de->inode = cpu_to_fs16(SYSV_SB(inode->i_sb), inode->i_ino);
err = dir_commit_chunk(page, pos, SYSV_DIRSIZE);
dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
mark_inode_dirty(dir);
out_page:
dir_put_page(page);
out:
return err;
out_unlock:
unlock_page(page);
goto out_page;
}
/*
* ok, we cannot use strncmp, as the name is not in our data space. [Now it is!]
* Thus we'll have to use sysv_match. No big problem. Match also makes
* some sanity tests.
*
* NOTE! unlike strncmp, sysv_match returns 1 for success, 0 for failure.
*/
static int sysv_match(int len, const char * name, struct sysv_dir_entry * de)
{
if (!de->inode || len > SYSV_NAMELEN)
return 0;
/* "" means "." ---> so paths like "/usr/lib//libc.a" work */
if (!len && (de->name[0]=='.') && (de->name[1]=='\0'))
return 1;
return namecompare(len, SYSV_NAMELEN, name, de->name);
}
int sysv_add_link(struct dentry *dentry, struct inode *inode)
{
struct inode *dir = dentry->d_parent->d_inode;
const char * name = dentry->d_name.name;
int namelen = dentry->d_name.len;
struct page *page = NULL;
struct sysv_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 */
for (n = 0; n <= npages; n++) {
page = dir_get_page(dir, n);
err = PTR_ERR(page);
if (IS_ERR(page))
goto out;
kaddr = (char*)page_address(page);
de = (struct sysv_dir_entry *)kaddr;
kaddr += PAGE_CACHE_SIZE - SYSV_DIRSIZE;
while ((char *)de <= kaddr) {
if (!de->inode)
goto got_it;
err = -EEXIST;
if (namecompare(namelen, SYSV_NAMELEN, name, de->name))
goto out_page;
de++;
}
dir_put_page(page);
}
BUG();
return -EINVAL;
got_it:
from = (char*)de - (char*)page_address(page);
to = from + SYSV_DIRSIZE;
lock_page(page);
err = page->mapping->a_ops->prepare_write(NULL, page, from, to);
if (err)
goto out_unlock;
memcpy (de->name, name, namelen);
memset (de->name + namelen, 0, SYSV_DIRSIZE - namelen - 2);
de->inode = cpu_to_fs16(inode->i_sb, inode->i_ino);
err = dir_commit_chunk(page, from, to);
dir->i_mtime = dir->i_ctime = CURRENT_TIME;
mark_inode_dirty(dir);
out_unlock:
UnlockPage(page);
out_page:
dir_put_page(page);
out:
return err;
}
/*
* ok, we cannot use strncmp, as the name is not in our data space.
* Thus we'll have to use minix_match. No big problem. Match also makes
* some sanity tests.
*
* NOTE! unlike strncmp, minix_match returns 1 for success, 0 for failure.
*
* Note2: bh must already be mapped!
*/
static int elksfs_match(size_t len, char *name, struct buffer_head *bh,
loff_t *offset, register struct elksfs_sb_info *info)
{
register struct elksfs_dir_entry *de;
de = (struct elksfs_dir_entry *) (bh->b_data + *offset);
*offset += info->s_dirsize;
if (!de->inode || (unsigned long int) len > info->s_namelen)
return 0;
/* "" means "." ---> so paths like "/usr/lib//libc.a" work */
if (!len && (de->name[0] == '.') && (de->name[1] == '\0'))
return 1;
return namecompare(len, (size_t) info->s_namelen, name, de->name);
}
/*
* ok, we cannot use strncmp, as the name is not in our data space.
* Thus we'll have to use minix_match. No big problem. Match also makes
* some sanity tests.
*
* NOTE! unlike strncmp, minix_match returns 1 for success, 0 for failure.
*
* Note2: bh must already be mapped!
*/
static int minix_match(size_t len,
char *name,
struct buffer_head *bh,
loff_t offset, register struct minix_sb_info *info)
{
register struct minix_dir_entry *de;
de = (struct minix_dir_entry *) (bh->b_data + offset);
if (!de->inode || len > info->s_namelen) {
return 0;
}
/* "" means "." ---> so paths like "/usr/lib//libc.a" work */
if (!len && (de->name[0] == '.') && (de->name[1] == '\0')) {
return 1;
}
return namecompare(len, info->s_namelen, name, de->name);
}
/*
* sysv_find_entry()
*
* finds an entry in the specified directory with the wanted name. It
* returns the cache buffer in which the entry was found, and the entry
* itself (as a parameter - res_dir). It does NOT read the inode of the
* entry - you'll have to do that yourself if you want to.
*/
struct sysv_dir_entry *sysv_find_entry(struct dentry *dentry, struct page **res_page)
{
const char * name = dentry->d_name.name;
int namelen = dentry->d_name.len;
struct inode * dir = dentry->d_parent->d_inode;
unsigned long start, n;
unsigned long npages = dir_pages(dir);
struct page *page = NULL;
struct sysv_dir_entry *de;
*res_page = NULL;
start = SYSV_I(dir)->i_dir_start_lookup;
if (start >= npages)
start = 0;
n = start;
do {
char *kaddr;
page = dir_get_page(dir, n);
if (!IS_ERR(page)) {
kaddr = (char*)page_address(page);
de = (struct sysv_dir_entry *) kaddr;
kaddr += PAGE_CACHE_SIZE - SYSV_DIRSIZE;
for ( ; (char *) de <= kaddr ; de++) {
if (!de->inode)
continue;
if (namecompare(namelen, SYSV_NAMELEN,
name, de->name))
goto found;
}
dir_put_page(page);
}
if (++n >= npages)
n = 0;
} while (n != start);
return NULL;
found:
SYSV_I(dir)->i_dir_start_lookup = n;
*res_page = page;
return de;
}
/*
* minix_find_entry()
*
* finds an entry in the specified directory with the wanted name. It
* returns the cache buffer in which the entry was found, and the entry
* itself (as a parameter - res_dir). It does NOT read the inode of the
* entry - you'll have to do that yourself if you want to.
*/
static struct buffer_head * minix_find_entry(struct inode * dir,
const char * name, int namelen, struct minix_dir_entry ** res_dir)
{
unsigned long block, offset;
struct buffer_head * bh;
struct minix_sb_info * info;
struct minix_dir_entry *de;
*res_dir = NULL;
if (!dir || !dir->i_sb)
return NULL;
info = &dir->i_sb->u.minix_sb;
if (namelen > info->s_namelen) {
#ifdef NO_TRUNCATE
return NULL;
#else
namelen = info->s_namelen;
#endif
}
bh = NULL;
block = offset = 0;
while (block*BLOCK_SIZE+offset < dir->i_size) {
if (!bh) {
bh = minix_bread(dir,block,0);
if (!bh) {
block++;
continue;
}
}
de = (struct minix_dir_entry *) (bh->b_data + offset);
offset += info->s_dirsize;
if (de->inode && namecompare(namelen,info->s_namelen,name,de->name)) {
*res_dir = de;
return bh;
}
if (offset < bh->b_size)
continue;
brelse(bh);
bh = NULL;
offset = 0;
block++;
}
brelse(bh);
return NULL;
}
static int elksfs_add_entry(register struct inode *dir, char *name,
size_t namelen, struct buffer_head **res_buf,
struct elksfs_dir_entry **res_dir)
{
struct buffer_head *bh;
struct elksfs_dir_entry *de;
struct elksfs_sb_info *info;
unsigned long int i;
block_t block;
loff_t offset;
*res_buf = NULL;
*res_dir = NULL;
if (!dir || !dir->i_sb)
return -ENOENT;
info = &dir->i_sb->u.elksfs_sb;
if (namelen > info->s_namelen) {
#ifdef NO_TRUNCATE
return -ENAMETOOLONG;
#else
namelen = info->s_namelen;
#endif
}
if (!namelen)
return -ENOENT;
bh = NULL;
block = 0;
offset = 0;
while (1) {
if (!bh) {
bh = elksfs_bread(dir, block, 1);
if (!bh)
return -ENOSPC;
}
map_buffer(bh);
de = (struct elksfs_dir_entry *) (bh->b_data + offset);
offset += info->s_dirsize;
if (block * 1024 + offset > dir->i_size) {
de->inode = 0;
dir->i_size = block * 1024 + offset;
dir->i_dirt = 1;
}
if (de->inode) {
if (namecompare(namelen, (size_t) info->s_namelen, name,
de->name)) {
debug2("ELKSFSadd_entry: file %t==%s (already exists)\n",
name, de->name);
unmap_brelse(bh);
return -EEXIST;
}
} else {
dir->i_mtime = dir->i_ctime = CURRENT_TIME;
dir->i_dirt = 1;
for (i = 0; i < info->s_namelen; i++)
de->name[i] = (i < namelen)
? (char) get_fs_byte((unsigned char *) name + i)
: 0;
#ifdef BLOAT_FS
dir->i_version = ++event;
#endif
unmap_buffer(bh);
mark_buffer_dirty(bh, 1);
*res_dir = de;
break;
}
if (offset < 1024)
continue;
printk("elksfs_add_entry may need another unmap_buffer :)\n");
brelse(bh);
bh = NULL;
offset = 0;
block++;
}
*res_buf = bh;
return 0;
}
static int minix_add_entry(register struct inode *dir,
char *name,
size_t namelen,
ino_t ino)
{
unsigned short block;
loff_t offset;
register struct buffer_head *bh;
struct minix_dir_entry *de;
struct minix_sb_info *info;
if (!dir || !dir->i_sb)
return -ENOENT;
info = &dir->i_sb->u.minix_sb;
if (namelen > info->s_namelen) {
#ifdef NO_TRUNCATE
return -ENAMETOOLONG;
#else
namelen = info->s_namelen;
#endif
}
if (!namelen)
return -ENOENT;
bh = NULL;
block = 0;
offset = 0L;
while (1) {
if (!bh) {
bh = minix_bread(dir, block, 1);
if (!bh)
return -ENOSPC;
map_buffer(bh);
}
de = (struct minix_dir_entry *) (bh->b_data + offset);
offset += info->s_dirsize;
if (block * 1024L + offset > dir->i_size) {
de->inode = 0;
dir->i_size = block * 1024L + offset;
dir->i_dirt = 1;
}
if (de->inode) {
if (namecompare(namelen, info->s_namelen, name, de->name)) {
debug2("MINIXadd_entry: file %t==%s (already exists)\n",
name, de->name);
unmap_brelse(bh);
return -EEXIST;
}
} else {
size_t i;
dir->i_mtime = dir->i_ctime = CURRENT_TIME;
dir->i_dirt = 1;
memcpy_fromfs(de->name, name, namelen);
if((i = info->s_namelen - namelen) > 0)
memset(de->name + namelen, 0, i);
#ifdef BLOAT_FS
dir->i_version = ++event;
#endif
de->inode = ino;
mark_buffer_dirty(bh, 1);
unmap_brelse(bh);
break;
}
if (offset >= BLOCK_SIZE) {
unmap_brelse(bh);
bh = NULL;
offset = 0;
block++;
}
}
return 0;
}
/*
* sysv_add_entry()
*
* adds a file entry to the specified directory, returning a possible
* error value if it fails.
*
* NOTE!! The inode part of 'de' is left at 0 - which means you
* may not sleep between calling this and putting something into
* the entry, as someone else might have used it while you slept.
*/
static int sysv_add_entry(struct inode * dir,
const char * name, int namelen,
struct buffer_head ** res_buf,
struct sysv_dir_entry ** res_dir)
{
struct super_block * sb;
int i;
unsigned long pos, block, offset; /* pos = block * block_size + offset */
struct buffer_head * bh;
struct sysv_dir_entry * de;
*res_buf = NULL;
*res_dir = NULL;
sb = dir->i_sb;
if (namelen > SYSV_NAMELEN) {
if (sb->sv_truncate)
namelen = SYSV_NAMELEN;
else
return -ENAMETOOLONG;
}
if (!namelen)
return -ENOENT;
bh = NULL;
pos = block = offset = 0;
while (1) {
if (!bh) {
bh = sysv_file_bread(dir, block, 1);
if (!bh)
return -ENOSPC;
}
de = (struct sysv_dir_entry *) (bh->b_data + offset);
pos += SYSV_DIRSIZE;
offset += SYSV_DIRSIZE;
if (pos > dir->i_size) {
de->inode = 0;
dir->i_size = pos;
mark_inode_dirty(dir);
}
if (de->inode) {
if (namecompare(namelen, SYSV_NAMELEN, name, de->name)) {
brelse(bh);
return -EEXIST;
}
} else {
dir->i_mtime = dir->i_ctime = CURRENT_TIME;
mark_inode_dirty(dir);
for (i = 0; i < SYSV_NAMELEN ; i++)
de->name[i] = (i < namelen) ? name[i] : 0;
mark_buffer_dirty(bh);
*res_dir = de;
break;
}
if (offset < sb->sv_block_size)
continue;
brelse(bh);
bh = NULL;
offset = 0; block++;
}
*res_buf = bh;
return 0;
}
/*
* minix_add_entry()
*
* adds a file entry to the specified directory, returning a possible
* error value if it fails.
*
* NOTE!! The inode part of 'de' is left at 0 - which means you
* may not sleep between calling this and putting something into
* the entry, as someone else might have used it while you slept.
*/
static int minix_add_entry(struct inode * dir,
const char * name, int namelen,
struct buffer_head ** res_buf,
struct minix_dir_entry ** res_dir)
{
int i;
unsigned long block, offset;
struct buffer_head * bh;
struct minix_dir_entry * de;
struct minix_sb_info * info;
*res_buf = NULL;
*res_dir = NULL;
if (!dir || !dir->i_sb)
return -ENOENT;
info = &dir->i_sb->u.minix_sb;
if (namelen > info->s_namelen) {
#ifdef NO_TRUNCATE
return -ENAMETOOLONG;
#else
namelen = info->s_namelen;
#endif
}
if (!namelen)
return -ENOENT;
bh = NULL;
block = offset = 0;
while (1) {
if (!bh) {
bh = minix_bread(dir,block,1);
if (!bh)
return -ENOSPC;
}
de = (struct minix_dir_entry *) (bh->b_data + offset);
offset += info->s_dirsize;
if (block*bh->b_size + offset > dir->i_size) {
de->inode = 0;
dir->i_size = block*bh->b_size + offset;
mark_inode_dirty(dir);
}
if (de->inode) {
if (namecompare(namelen, info->s_namelen, name, de->name)) {
brelse(bh);
return -EEXIST;
}
} else {
dir->i_mtime = dir->i_ctime = CURRENT_TIME;
mark_inode_dirty(dir);
for (i = 0; i < info->s_namelen ; i++)
de->name[i] = (i < namelen) ? name[i] : 0;
dir->i_version = ++event;
mark_buffer_dirty(bh, 1);
*res_dir = de;
break;
}
if (offset < bh->b_size)
continue;
brelse(bh);
bh = NULL;
offset = 0;
block++;
}
*res_buf = bh;
return 0;
}
static int minix_add_entry(register struct inode *dir,
char *name,
size_t namelen,
struct buffer_head **res_buf,
struct minix_dir_entry **res_dir)
{
unsigned short block;
loff_t offset;
register struct buffer_head *bh;
struct minix_dir_entry *de;
struct minix_sb_info *info;
*res_buf = NULL;
*res_dir = NULL;
if (!dir || !dir->i_sb)
return -ENOENT;
info = &dir->i_sb->u.minix_sb;
if (namelen > info->s_namelen) {
#ifdef NO_TRUNCATE
return -ENAMETOOLONG;
#else
namelen = info->s_namelen;
#endif
}
if (!namelen)
return -ENOENT;
bh = NULL;
block = 0;
offset = 0L;
while (1) {
if (!bh) {
bh = minix_bread(dir, block, 1);
if (!bh)
return -ENOSPC;
map_buffer(bh);
}
de = (struct minix_dir_entry *) (bh->b_data + offset);
offset += info->s_dirsize;
if (block * 1024L + offset > dir->i_size) {
de->inode = 0;
dir->i_size = block * 1024L + offset;
dir->i_dirt = 1;
}
if (de->inode) {
if (namecompare(namelen, info->s_namelen, name, de->name)) {
debug2("MINIXadd_entry: file %t==%s (already exists)\n",
name, de->name);
unmap_brelse(bh);
return -EEXIST;
}
} else {
size_t i;
dir->i_mtime = dir->i_ctime = CURRENT_TIME;
dir->i_dirt = 1;
for (i = 0; i < info->s_namelen; i++)
de->name[i] = (i < namelen) ? (char) get_fs_byte(name + i)
: '\0';
#ifdef BLOAT_FS
dir->i_version = ++event;
#endif
unmap_buffer(bh);
mark_buffer_dirty(bh, 1);
*res_dir = de;
break;
}
if (offset < 1024)
continue;
unmap_brelse(bh);
bh = NULL;
offset = 0;
block++;
}
*res_buf = bh;
return 0;
}