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;
}
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;
}
static int sysv_readdir(struct file * filp, void * dirent, filldir_t filldir)
{
unsigned long pos = filp->f_pos;
struct inode *inode = filp->f_dentry->d_inode;
struct super_block *sb = inode->i_sb;
unsigned offset = pos & ~PAGE_CACHE_MASK;
unsigned long n = pos >> PAGE_CACHE_SHIFT;
unsigned long npages = dir_pages(inode);
lock_kernel();
pos = (pos + SYSV_DIRSIZE-1) & ~(SYSV_DIRSIZE-1);
if (pos >= inode->i_size)
goto done;
for ( ; n < npages; n++, offset = 0) {
char *kaddr, *limit;
struct sysv_dir_entry *de;
struct page *page = dir_get_page(inode, n);
if (IS_ERR(page))
continue;
kaddr = (char *)page_address(page);
de = (struct sysv_dir_entry *)(kaddr+offset);
limit = kaddr + PAGE_CACHE_SIZE - SYSV_DIRSIZE;
for ( ;(char*)de <= limit; de++) {
char *name = de->name;
int over;
if (!de->inode)
continue;
offset = (char *)de - kaddr;
over = filldir(dirent, name, strnlen(name,SYSV_NAMELEN),
(n<<PAGE_CACHE_SHIFT) | offset,
fs16_to_cpu(SYSV_SB(sb), de->inode),
DT_UNKNOWN);
if (over) {
dir_put_page(page);
goto done;
}
}
dir_put_page(page);
}
done:
filp->f_pos = (n << PAGE_CACHE_SHIFT) | offset;
update_atime(inode);
unlock_kernel();
return 0;
}
/**
* vxfs_find_entry - find a mathing directory entry for a dentry
* @ip: directory inode
* @dp: dentry for which we want to find a direct
* @ppp: gets filled with the page the return value sits in
*
* Description:
* vxfs_find_entry finds a &struct vxfs_direct for the VFS directory
* cache entry @dp. @ppp will be filled with the page the return
* value resides in.
*
* Returns:
* The wanted direct on success, else a NULL pointer.
*/
static struct vxfs_direct *
vxfs_find_entry(struct inode *ip, struct dentry *dp, struct page **ppp)
{
u_long npages, page, nblocks, pblocks, block;
u_long bsize = ip->i_sb->s_blocksize;
const char *name = dp->d_name.name;
int namelen = dp->d_name.len;
npages = dir_pages(ip);
nblocks = dir_blocks(ip);
pblocks = VXFS_BLOCK_PER_PAGE(ip->i_sb);
for (page = 0; page < npages; page++) {
caddr_t kaddr;
struct page *pp;
pp = vxfs_get_page(ip->i_mapping, page);
if (IS_ERR(pp))
continue;
kaddr = (caddr_t)page_address(pp);
for (block = 0; block <= nblocks && block <= pblocks; block++) {
caddr_t baddr, limit;
struct vxfs_dirblk *dbp;
struct vxfs_direct *de;
baddr = kaddr + (block * bsize);
limit = baddr + bsize - VXFS_DIRLEN(1);
dbp = (struct vxfs_dirblk *)baddr;
de = (struct vxfs_direct *)(baddr + VXFS_DIRBLKOV(dbp));
for (; (caddr_t)de <= limit; de = vxfs_next_entry(de)) {
if (!de->d_reclen)
break;
if (!de->d_ino)
continue;
if (vxfs_match(namelen, name, de)) {
*ppp = pp;
return (de);
}
}
}
vxfs_put_page(pp);
}
return NULL;
}
/*
* 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;
}
static int sysv_readdir(struct file *file, struct dir_context *ctx)
{
unsigned long pos = ctx->pos;
struct inode *inode = file_inode(file);
struct super_block *sb = inode->i_sb;
unsigned long npages = dir_pages(inode);
unsigned offset;
unsigned long n;
ctx->pos = pos = (pos + SYSV_DIRSIZE-1) & ~(SYSV_DIRSIZE-1);
if (pos >= inode->i_size)
return 0;
offset = pos & ~PAGE_MASK;
n = pos >> PAGE_SHIFT;
for ( ; n < npages; n++, offset = 0) {
char *kaddr, *limit;
struct sysv_dir_entry *de;
struct page *page = dir_get_page(inode, n);
if (IS_ERR(page))
continue;
kaddr = (char *)page_address(page);
de = (struct sysv_dir_entry *)(kaddr+offset);
limit = kaddr + PAGE_SIZE - SYSV_DIRSIZE;
for ( ;(char*)de <= limit; de++, ctx->pos += sizeof(*de)) {
char *name = de->name;
if (!de->inode)
continue;
if (!dir_emit(ctx, name, strnlen(name,SYSV_NAMELEN),
fs16_to_cpu(SYSV_SB(sb), de->inode),
DT_UNKNOWN)) {
dir_put_page(page);
return 0;
}
}
dir_put_page(page);
}
return 0;
}
/*
* routine to check that the specified directory is empty (for rmdir)
*/
int sysv_empty_dir(struct inode * inode)
{
struct super_block *sb = inode->i_sb;
struct page *page = NULL;
unsigned long i, npages = dir_pages(inode);
for (i = 0; i < npages; i++) {
char *kaddr;
struct sysv_dir_entry * de;
page = dir_get_page(inode, i);
if (IS_ERR(page))
continue;
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;
/* check for . and .. */
if (de->name[0] != '.')
goto not_empty;
if (!de->name[1]) {
if (de->inode == cpu_to_fs16(SYSV_SB(sb),
inode->i_ino))
continue;
goto not_empty;
}
if (de->name[1] != '.' || de->name[2])
goto not_empty;
}
dir_put_page(page);
}
return 1;
not_empty:
dir_put_page(page);
return 0;
}
/**
* vxfs_readdir - read a directory
* @fp: the directory to read
* @retp: return buffer
* @filler: filldir callback
*
* Description:
* vxfs_readdir fills @retp with directory entries from @fp
* using the VFS supplied callback @filler.
*
* Returns:
* Zero.
*/
static int
vxfs_readdir(struct file *fp, void *retp, filldir_t filler)
{
struct inode *ip = fp->f_path.dentry->d_inode;
struct super_block *sbp = ip->i_sb;
u_long bsize = sbp->s_blocksize;
u_long page, npages, block, pblocks, nblocks, offset;
loff_t pos;
switch ((long)fp->f_pos) {
case 0:
if (filler(retp, ".", 1, fp->f_pos, ip->i_ino, DT_DIR) < 0)
goto out;
fp->f_pos++;
/* fallthrough */
case 1:
if (filler(retp, "..", 2, fp->f_pos, VXFS_INO(ip)->vii_dotdot, DT_DIR) < 0)
goto out;
fp->f_pos++;
/* fallthrough */
}
pos = fp->f_pos - 2;
if (pos > VXFS_DIRROUND(ip->i_size))
return 0;
npages = dir_pages(ip);
nblocks = dir_blocks(ip);
pblocks = VXFS_BLOCK_PER_PAGE(sbp);
page = pos >> PAGE_CACHE_SHIFT;
offset = pos & ~PAGE_CACHE_MASK;
block = (u_long)(pos >> sbp->s_blocksize_bits) % pblocks;
for (; page < npages; page++, block = 0) {
caddr_t kaddr;
struct page *pp;
pp = vxfs_get_page(ip->i_mapping, page);
if (IS_ERR(pp))
continue;
kaddr = (caddr_t)page_address(pp);
for (; block <= nblocks && block <= pblocks; block++) {
caddr_t baddr, limit;
struct vxfs_dirblk *dbp;
struct vxfs_direct *de;
baddr = kaddr + (block * bsize);
limit = baddr + bsize - VXFS_DIRLEN(1);
dbp = (struct vxfs_dirblk *)baddr;
de = (struct vxfs_direct *)
(offset ?
(kaddr + offset) :
(baddr + VXFS_DIRBLKOV(dbp)));
for (; (caddr_t)de <= limit; de = vxfs_next_entry(de)) {
int over;
if (!de->d_reclen)
break;
if (!de->d_ino)
continue;
offset = (caddr_t)de - kaddr;
over = filler(retp, de->d_name, de->d_namelen,
((page << PAGE_CACHE_SHIFT) | offset) + 2,
de->d_ino, DT_UNKNOWN);
if (over) {
vxfs_put_page(pp);
goto done;
}
}
offset = 0;
}
vxfs_put_page(pp);
offset = 0;
}
done:
fp->f_pos = ((page << PAGE_CACHE_SHIFT) | offset) + 2;
out:
return 0;
}
/**
* vxfs_readdir - read a directory
* @fp: the directory to read
* @retp: return buffer
* @filler: filldir callback
*
* Description:
* vxfs_readdir fills @retp with directory entries from @fp
* using the VFS supplied callback @filler.
*
* Returns:
* Zero.
*/
static int
vxfs_readdir(struct file *fp, struct dir_context *ctx)
{
struct inode *ip = file_inode(fp);
struct super_block *sbp = ip->i_sb;
u_long bsize = sbp->s_blocksize;
u_long page, npages, block, pblocks, nblocks, offset;
loff_t pos;
if (ctx->pos == 0) {
if (!dir_emit_dot(fp, ctx))
return 0;
ctx->pos = 1;
}
if (ctx->pos == 1) {
if (!dir_emit(ctx, "..", 2, VXFS_INO(ip)->vii_dotdot, DT_DIR))
return 0;
ctx->pos = 2;
}
pos = ctx->pos - 2;
if (pos > VXFS_DIRROUND(ip->i_size))
return 0;
npages = dir_pages(ip);
nblocks = dir_blocks(ip);
pblocks = VXFS_BLOCK_PER_PAGE(sbp);
page = pos >> PAGE_CACHE_SHIFT;
offset = pos & ~PAGE_CACHE_MASK;
block = (u_long)(pos >> sbp->s_blocksize_bits) % pblocks;
for (; page < npages; page++, block = 0) {
char *kaddr;
struct page *pp;
pp = vxfs_get_page(ip->i_mapping, page);
if (IS_ERR(pp))
continue;
kaddr = (char *)page_address(pp);
for (; block <= nblocks && block <= pblocks; block++) {
char *baddr, *limit;
struct vxfs_dirblk *dbp;
struct vxfs_direct *de;
baddr = kaddr + (block * bsize);
limit = baddr + bsize - VXFS_DIRLEN(1);
dbp = (struct vxfs_dirblk *)baddr;
de = (struct vxfs_direct *)
(offset ?
(kaddr + offset) :
(baddr + VXFS_DIRBLKOV(dbp)));
for (; (char *)de <= limit; de = vxfs_next_entry(de)) {
if (!de->d_reclen)
break;
if (!de->d_ino)
continue;
offset = (char *)de - kaddr;
ctx->pos = ((page << PAGE_CACHE_SHIFT) | offset) + 2;
if (!dir_emit(ctx, de->d_name, de->d_namelen,
de->d_ino, DT_UNKNOWN)) {
vxfs_put_page(pp);
return 0;
}
}
offset = 0;
}
vxfs_put_page(pp);
offset = 0;
}
ctx->pos = ((page << PAGE_CACHE_SHIFT) | offset) + 2;
return 0;
}
