static int sysfs_readdir(struct file *file, struct dir_context *ctx)
{
struct dentry *dentry = file->f_path.dentry;
struct sysfs_dirent *parent_sd = dentry->d_fsdata;
struct sysfs_dirent *pos = file->private_data;
enum kobj_ns_type type;
const void *ns;
type = sysfs_ns_type(parent_sd);
ns = sysfs_info(dentry->d_sb)->ns[type];
if (!dir_emit_dots(file, ctx))
return 0;
mutex_lock(&sysfs_mutex);
for (pos = sysfs_dir_pos(ns, parent_sd, ctx->pos, pos);
pos;
pos = sysfs_dir_next_pos(ns, parent_sd, ctx->pos, pos)) {
const char *name = pos->s_name;
unsigned int type = dt_type(pos);
int len = strlen(name);
ino_t ino = pos->s_ino;
ctx->pos = pos->s_hash;
file->private_data = sysfs_get(pos);
mutex_unlock(&sysfs_mutex);
if (!dir_emit(ctx, name, len, ino, type))
return 0;
mutex_lock(&sysfs_mutex);
}
mutex_unlock(&sysfs_mutex);
file->private_data = NULL;
ctx->pos = INT_MAX;
return 0;
}
static int
zpl_shares_iterate(struct file *filp, struct dir_context *ctx)
{
fstrans_cookie_t cookie;
cred_t *cr = CRED();
zfs_sb_t *zsb = ITOZSB(filp->f_path.dentry->d_inode);
znode_t *dzp;
int error = 0;
ZFS_ENTER(zsb);
cookie = spl_fstrans_mark();
if (zsb->z_shares_dir == 0) {
dir_emit_dots(filp, ctx);
goto out;
}
error = -zfs_zget(zsb, zsb->z_shares_dir, &dzp);
if (error)
goto out;
crhold(cr);
error = -zfs_readdir(ZTOI(dzp), ctx, cr);
crfree(cr);
VN_RELE(ZTOV(dzp));
out:
spl_fstrans_unmark(cookie);
ZFS_EXIT(zsb);
ASSERT3S(error, <=, 0);
return (error);
}
/*
* Get root directory contents.
*/
static int
zpl_root_iterate(struct file *filp, struct dir_context *ctx)
{
zfs_sb_t *zsb = ITOZSB(filp->f_path.dentry->d_inode);
int error = 0;
ZFS_ENTER(zsb);
if (!dir_emit_dots(filp, ctx))
goto out;
if (ctx->pos == 2) {
if (!dir_emit(ctx, ZFS_SNAPDIR_NAME, strlen(ZFS_SNAPDIR_NAME),
ZFSCTL_INO_SNAPDIR, DT_DIR))
goto out;
ctx->pos++;
}
if (ctx->pos == 3) {
if (!dir_emit(ctx, ZFS_SHAREDIR_NAME, strlen(ZFS_SHAREDIR_NAME),
ZFSCTL_INO_SHARES, DT_DIR))
goto out;
ctx->pos++;
}
out:
ZFS_EXIT(zsb);
return (error);
}
static int proc_ns_dir_readdir(struct file *file, struct dir_context *ctx)
{
struct task_struct *task = get_proc_task(file_inode(file));
const struct proc_ns_operations **entry, **last;
if (!task)
return -ENOENT;
if (!dir_emit_dots(file, ctx))
goto out;
if (ctx->pos >= 2 + ARRAY_SIZE(ns_entries))
goto out;
entry = ns_entries + (ctx->pos - 2);
last = &ns_entries[ARRAY_SIZE(ns_entries) - 1];
while (entry <= last) {
const struct proc_ns_operations *ops = *entry;
if (!proc_fill_cache(file, ctx, ops->name, strlen(ops->name),
proc_ns_instantiate, task, ops))
break;
ctx->pos++;
entry++;
}
out:
put_task_struct(task);
return 0;
}
static int mfs_readdir(struct file *file, struct dir_context *ctx)
{
char buf[512] = {0};
struct dentry *de = file->f_dentry;
get_file_path_from_dentry(de, buf, 512);
if(ctx->pos > 0) {
return 1;
}
if(!dir_emit_dots(file, ctx)) {
return 0;
}
__mfs_readdir(buf, file, ctx);
return 1;
}
static int proc_readfd_common(struct file *file, struct dir_context *ctx,
instantiate_t instantiate)
{
struct task_struct *p = get_proc_task(file_inode(file));
struct files_struct *files;
unsigned int fd;
if (!p)
return -ENOENT;
if (!dir_emit_dots(file, ctx))
goto out;
files = get_files_struct(p);
if (!files)
goto out;
rcu_read_lock();
for (fd = ctx->pos - 2;
fd < files_fdtable(files)->max_fds;
fd++, ctx->pos++) {
char name[PROC_NUMBUF];
int len;
if (!fcheck_files(files, fd))
continue;
rcu_read_unlock();
len = snprintf(name, sizeof(name), "%u", fd);
if (!proc_fill_cache(file, ctx,
name, len, instantiate, p,
(void *)(unsigned long)fd))
goto out_fd_loop;
cond_resched();
rcu_read_lock();
}
rcu_read_unlock();
out_fd_loop:
put_files_struct(files);
out:
put_task_struct(p);
return 0;
}
static int
HgfsReaddir(struct file *file, // IN:
struct dir_context *ctx) // IN:
{
HgfsFileInfo *fInfo = FILE_GET_FI_P(file);
if (0 == ctx->pos) {
fInfo->direntPos = 0;
}
/* If either dot and dotdot are filled in for us we can exit. */
if (!dir_emit_dots(file, ctx)) {
LOG(6, (KERN_DEBUG "VMware hgfs: %s: dir_emit_dots(%s, @ %Lu)\n",
__func__, file->f_dentry->d_name.name, ctx->pos));
return 0;
}
/* It is sufficient to pass the context as it contains the filler function. */
return HgfsDoReaddir(file, TRUE, NULL, ctx, &ctx->pos, &fInfo->direntPos);
}
/* FIXME: readdir currently has it's own dir_walk code. I don't see a good
* way to combine the two copies */
static int logfs_readdir(struct file *file, struct dir_context *ctx)
{
struct inode *dir = file_inode(file);
loff_t pos;
struct page *page;
struct logfs_disk_dentry *dd;
if (ctx->pos < 0)
return -EINVAL;
if (!dir_emit_dots(file, ctx))
return 0;
pos = ctx->pos - 2;
BUG_ON(pos < 0);
for (;; pos++, ctx->pos++) {
bool full;
if (beyond_eof(dir, pos))
break;
if (!logfs_exist_block(dir, pos)) {
/* deleted dentry */
pos = dir_seek_data(dir, pos);
continue;
}
page = read_cache_page(dir->i_mapping, pos,
(filler_t *)logfs_readpage, NULL);
if (IS_ERR(page))
return PTR_ERR(page);
dd = kmap(page);
BUG_ON(dd->namelen == 0);
full = !dir_emit(ctx, (char *)dd->name,
be16_to_cpu(dd->namelen),
be64_to_cpu(dd->ino), dd->type);
kunmap(page);
page_cache_release(page);
if (full)
break;
}
return 0;
}
static int
zpl_snapdir_iterate(struct file *filp, struct dir_context *ctx)
{
zfs_sb_t *zsb = ITOZSB(filp->f_path.dentry->d_inode);
fstrans_cookie_t cookie;
char snapname[MAXNAMELEN];
boolean_t case_conflict;
uint64_t id, pos;
int error = 0;
ZFS_ENTER(zsb);
cookie = spl_fstrans_mark();
if (!dir_emit_dots(filp, ctx))
goto out;
pos = ctx->pos;
while (error == 0) {
dsl_pool_config_enter(dmu_objset_pool(zsb->z_os), FTAG);
error = -dmu_snapshot_list_next(zsb->z_os, MAXNAMELEN,
snapname, &id, &pos, &case_conflict);
dsl_pool_config_exit(dmu_objset_pool(zsb->z_os), FTAG);
if (error)
goto out;
if (!dir_emit(ctx, snapname, strlen(snapname),
ZFSCTL_INO_SHARES - id, DT_DIR))
goto out;
ctx->pos = pos;
}
out:
spl_fstrans_unmark(cookie);
ZFS_EXIT(zsb);
if (error == -ENOENT)
return (0);
return (error);
}
static int jffs2_readdir(struct file *file, struct dir_context *ctx)
{
struct inode *inode = file_inode(file);
struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
struct jffs2_full_dirent *fd;
unsigned long curofs = 1;
jffs2_dbg(1, "jffs2_readdir() for dir_i #%lu\n", inode->i_ino);
if (!dir_emit_dots(file, ctx))
return 0;
mutex_lock(&f->sem);
for (fd = f->dents; fd; fd = fd->next) {
curofs++;
/* First loop: curofs = 2; pos = 2 */
if (curofs < ctx->pos) {
jffs2_dbg(2, "Skipping dirent: \"%s\", ino #%u, type %d, because curofs %ld < offset %ld\n",
fd->name, fd->ino, fd->type, curofs, (unsigned long)ctx->pos);
continue;
}
if (!fd->ino) {
jffs2_dbg(2, "Skipping deletion dirent \"%s\"\n",
fd->name);
ctx->pos++;
continue;
}
jffs2_dbg(2, "Dirent %ld: \"%s\", ino #%u, type %d\n",
(unsigned long)ctx->pos, fd->name, fd->ino, fd->type);
if (!dir_emit(ctx, fd->name, strlen(fd->name), fd->ino, fd->type))
break;
ctx->pos++;
}
mutex_unlock(&f->sem);
return 0;
}
static int kernfs_fop_readdir(struct file *file, struct dir_context *ctx)
{
struct dentry *dentry = file->f_path.dentry;
struct kernfs_node *parent = dentry->d_fsdata;
struct kernfs_node *pos = file->private_data;
const void *ns = NULL;
if (!dir_emit_dots(file, ctx))
return 0;
mutex_lock(&kernfs_mutex);
if (kernfs_ns_enabled(parent))
ns = kernfs_info(dentry->d_sb)->ns;
for (pos = kernfs_dir_pos(ns, parent, ctx->pos, pos);
pos;
pos = kernfs_dir_next_pos(ns, parent, ctx->pos, pos)) {
const char *name = pos->name;
unsigned int type = dt_type(pos);
int len = strlen(name);
ino_t ino = pos->ino;
ctx->pos = pos->hash;
file->private_data = pos;
kernfs_get(pos);
mutex_unlock(&kernfs_mutex);
if (!dir_emit(ctx, name, len, ino, type))
return 0;
mutex_lock(&kernfs_mutex);
}
mutex_unlock(&kernfs_mutex);
file->private_data = NULL;
ctx->pos = INT_MAX;
return 0;
}
int cifs_readdir(struct file *file, struct dir_context *ctx)
{
int rc = 0;
unsigned int xid;
int i;
struct cifs_tcon *tcon;
struct cifsFileInfo *cifsFile = NULL;
char *current_entry;
int num_to_fill = 0;
char *tmp_buf = NULL;
char *end_of_smb;
unsigned int max_len;
xid = get_xid();
/*
* Ensure FindFirst doesn't fail before doing filldir() for '.' and
* '..'. Otherwise we won't be able to notify VFS in case of failure.
*/
if (file->private_data == NULL) {
rc = initiate_cifs_search(xid, file);
cifs_dbg(FYI, "initiate cifs search rc %d\n", rc);
if (rc)
goto rddir2_exit;
}
if (!dir_emit_dots(file, ctx))
goto rddir2_exit;
/* 1) If search is active,
is in current search buffer?
if it before then restart search
if after then keep searching till find it */
cifsFile = file->private_data;
if (cifsFile->srch_inf.endOfSearch) {
if (cifsFile->srch_inf.emptyDir) {
cifs_dbg(FYI, "End of search, empty dir\n");
rc = 0;
goto rddir2_exit;
}
} /* else {
cifsFile->invalidHandle = true;
tcon->ses->server->close(xid, tcon, &cifsFile->fid);
} */
tcon = tlink_tcon(cifsFile->tlink);
rc = find_cifs_entry(xid, tcon, ctx->pos, file, ¤t_entry,
&num_to_fill);
if (rc) {
cifs_dbg(FYI, "fce error %d\n", rc);
goto rddir2_exit;
} else if (current_entry != NULL) {
cifs_dbg(FYI, "entry %lld found\n", ctx->pos);
} else {
cifs_dbg(FYI, "could not find entry\n");
goto rddir2_exit;
}
cifs_dbg(FYI, "loop through %d times filling dir for net buf %p\n",
num_to_fill, cifsFile->srch_inf.ntwrk_buf_start);
max_len = tcon->ses->server->ops->calc_smb_size(
cifsFile->srch_inf.ntwrk_buf_start);
end_of_smb = cifsFile->srch_inf.ntwrk_buf_start + max_len;
tmp_buf = kmalloc(UNICODE_NAME_MAX, GFP_KERNEL);
if (tmp_buf == NULL) {
rc = -ENOMEM;
goto rddir2_exit;
}
for (i = 0; i < num_to_fill; i++) {
if (current_entry == NULL) {
/* evaluate whether this case is an error */
cifs_dbg(VFS, "past SMB end, num to fill %d i %d\n",
num_to_fill, i);
break;
}
/*
* if buggy server returns . and .. late do we want to
* check for that here?
*/
*tmp_buf = 0;
rc = cifs_filldir(current_entry, file, ctx,
tmp_buf, max_len);
if (rc) {
if (rc > 0)
rc = 0;
break;
}
ctx->pos++;
if (ctx->pos ==
cifsFile->srch_inf.index_of_last_entry) {
cifs_dbg(FYI, "last entry in buf at pos %lld %s\n",
ctx->pos, tmp_buf);
cifs_save_resume_key(current_entry, cifsFile);
break;
} else
current_entry =
nxt_dir_entry(current_entry, end_of_smb,
cifsFile->srch_inf.info_level);
}
kfree(tmp_buf);
rddir2_exit:
free_xid(xid);
return rc;
}
static int
affs_readdir(struct file *file, struct dir_context *ctx)
{
struct inode *inode = file_inode(file);
struct super_block *sb = inode->i_sb;
struct buffer_head *dir_bh = NULL;
struct buffer_head *fh_bh = NULL;
unsigned char *name;
int namelen;
u32 i;
int hash_pos;
int chain_pos;
u32 ino;
int error = 0;
pr_debug("%s(ino=%lu,f_pos=%llx)\n", __func__, inode->i_ino, ctx->pos);
if (ctx->pos < 2) {
file->private_data = (void *)0;
if (!dir_emit_dots(file, ctx))
return 0;
}
affs_lock_dir(inode);
chain_pos = (ctx->pos - 2) & 0xffff;
hash_pos = (ctx->pos - 2) >> 16;
if (chain_pos == 0xffff) {
affs_warning(sb, "readdir", "More than 65535 entries in chain");
chain_pos = 0;
hash_pos++;
ctx->pos = ((hash_pos << 16) | chain_pos) + 2;
}
dir_bh = affs_bread(sb, inode->i_ino);
if (!dir_bh)
goto out_unlock_dir;
/* If the directory hasn't changed since the last call to readdir(),
* we can jump directly to where we left off.
*/
ino = (u32)(long)file->private_data;
if (ino && file->f_version == inode->i_version) {
pr_debug("readdir() left off=%d\n", ino);
goto inside;
}
ino = be32_to_cpu(AFFS_HEAD(dir_bh)->table[hash_pos]);
for (i = 0; ino && i < chain_pos; i++) {
fh_bh = affs_bread(sb, ino);
if (!fh_bh) {
affs_error(sb, "readdir","Cannot read block %d", i);
error = -EIO;
goto out_brelse_dir;
}
ino = be32_to_cpu(AFFS_TAIL(sb, fh_bh)->hash_chain);
affs_brelse(fh_bh);
fh_bh = NULL;
}
if (ino)
goto inside;
hash_pos++;
for (; hash_pos < AFFS_SB(sb)->s_hashsize; hash_pos++) {
ino = be32_to_cpu(AFFS_HEAD(dir_bh)->table[hash_pos]);
if (!ino)
continue;
ctx->pos = (hash_pos << 16) + 2;
inside:
do {
fh_bh = affs_bread(sb, ino);
if (!fh_bh) {
affs_error(sb, "readdir",
"Cannot read block %d", ino);
break;
}
namelen = min(AFFS_TAIL(sb, fh_bh)->name[0],
(u8)AFFSNAMEMAX);
name = AFFS_TAIL(sb, fh_bh)->name + 1;
pr_debug("readdir(): dir_emit(\"%.*s\", ino=%u), hash=%d, f_pos=%llx\n",
namelen, name, ino, hash_pos, ctx->pos);
if (!dir_emit(ctx, name, namelen, ino, DT_UNKNOWN))
goto done;
ctx->pos++;
ino = be32_to_cpu(AFFS_TAIL(sb, fh_bh)->hash_chain);
affs_brelse(fh_bh);
fh_bh = NULL;
} while (ino);
}
done:
file->f_version = inode->i_version;
file->private_data = (void *)(long)ino;
affs_brelse(fh_bh);
out_brelse_dir:
affs_brelse(dir_bh);
out_unlock_dir:
affs_unlock_dir(inode);
return error;
}
static int ubifs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
bool excl)
{
struct inode *inode;
struct ubifs_info *c = dir->i_sb->s_fs_info;
struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
.dirtied_ino = 1 };
struct ubifs_inode *dir_ui = ubifs_inode(dir);
struct fscrypt_name nm;
int err, sz_change;
/*
* Budget request settings: new inode, new direntry, changing the
* parent directory inode.
*/
dbg_gen("dent '%pd', mode %#hx in dir ino %lu",
dentry, mode, dir->i_ino);
err = ubifs_budget_space(c, &req);
if (err)
return err;
err = fscrypt_setup_filename(dir, &dentry->d_name, 0, &nm);
if (err)
goto out_budg;
sz_change = CALC_DENT_SIZE(fname_len(&nm));
inode = ubifs_new_inode(c, dir, mode);
if (IS_ERR(inode)) {
err = PTR_ERR(inode);
goto out_fname;
}
err = ubifs_init_security(dir, inode, &dentry->d_name);
if (err)
goto out_inode;
mutex_lock(&dir_ui->ui_mutex);
dir->i_size += sz_change;
dir_ui->ui_size = dir->i_size;
dir->i_mtime = dir->i_ctime = inode->i_ctime;
err = ubifs_jnl_update(c, dir, &nm, inode, 0, 0);
if (err)
goto out_cancel;
mutex_unlock(&dir_ui->ui_mutex);
ubifs_release_budget(c, &req);
fscrypt_free_filename(&nm);
insert_inode_hash(inode);
d_instantiate(dentry, inode);
return 0;
out_cancel:
dir->i_size -= sz_change;
dir_ui->ui_size = dir->i_size;
mutex_unlock(&dir_ui->ui_mutex);
out_inode:
make_bad_inode(inode);
iput(inode);
out_fname:
fscrypt_free_filename(&nm);
out_budg:
ubifs_release_budget(c, &req);
ubifs_err(c, "cannot create regular file, error %d", err);
return err;
}
static int do_tmpfile(struct inode *dir, struct dentry *dentry,
umode_t mode, struct inode **whiteout)
{
struct inode *inode;
struct ubifs_info *c = dir->i_sb->s_fs_info;
struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1};
struct ubifs_budget_req ino_req = { .dirtied_ino = 1 };
struct ubifs_inode *ui, *dir_ui = ubifs_inode(dir);
int err, instantiated = 0;
struct fscrypt_name nm;
/*
* Budget request settings: new dirty inode, new direntry,
* budget for dirtied inode will be released via writeback.
*/
dbg_gen("dent '%pd', mode %#hx in dir ino %lu",
dentry, mode, dir->i_ino);
err = fscrypt_setup_filename(dir, &dentry->d_name, 0, &nm);
if (err)
return err;
err = ubifs_budget_space(c, &req);
if (err) {
fscrypt_free_filename(&nm);
return err;
}
err = ubifs_budget_space(c, &ino_req);
if (err) {
ubifs_release_budget(c, &req);
fscrypt_free_filename(&nm);
return err;
}
inode = ubifs_new_inode(c, dir, mode);
if (IS_ERR(inode)) {
err = PTR_ERR(inode);
goto out_budg;
}
ui = ubifs_inode(inode);
if (whiteout) {
init_special_inode(inode, inode->i_mode, WHITEOUT_DEV);
ubifs_assert(inode->i_op == &ubifs_file_inode_operations);
}
err = ubifs_init_security(dir, inode, &dentry->d_name);
if (err)
goto out_inode;
mutex_lock(&ui->ui_mutex);
insert_inode_hash(inode);
if (whiteout) {
mark_inode_dirty(inode);
drop_nlink(inode);
*whiteout = inode;
} else {
d_tmpfile(dentry, inode);
}
ubifs_assert(ui->dirty);
instantiated = 1;
mutex_unlock(&ui->ui_mutex);
mutex_lock(&dir_ui->ui_mutex);
err = ubifs_jnl_update(c, dir, &nm, inode, 1, 0);
if (err)
goto out_cancel;
mutex_unlock(&dir_ui->ui_mutex);
ubifs_release_budget(c, &req);
return 0;
out_cancel:
mutex_unlock(&dir_ui->ui_mutex);
out_inode:
make_bad_inode(inode);
if (!instantiated)
iput(inode);
out_budg:
ubifs_release_budget(c, &req);
if (!instantiated)
ubifs_release_budget(c, &ino_req);
fscrypt_free_filename(&nm);
ubifs_err(c, "cannot create temporary file, error %d", err);
return err;
}
static int ubifs_tmpfile(struct inode *dir, struct dentry *dentry,
umode_t mode)
{
return do_tmpfile(dir, dentry, mode, NULL);
}
/**
* vfs_dent_type - get VFS directory entry type.
* @type: UBIFS directory entry type
*
* This function converts UBIFS directory entry type into VFS directory entry
* type.
*/
static unsigned int vfs_dent_type(uint8_t type)
{
switch (type) {
case UBIFS_ITYPE_REG:
return DT_REG;
case UBIFS_ITYPE_DIR:
return DT_DIR;
case UBIFS_ITYPE_LNK:
return DT_LNK;
case UBIFS_ITYPE_BLK:
return DT_BLK;
case UBIFS_ITYPE_CHR:
return DT_CHR;
case UBIFS_ITYPE_FIFO:
return DT_FIFO;
case UBIFS_ITYPE_SOCK:
return DT_SOCK;
default:
BUG();
}
return 0;
}
/*
* The classical Unix view for directory is that it is a linear array of
* (name, inode number) entries. Linux/VFS assumes this model as well.
* Particularly, 'readdir()' call wants us to return a directory entry offset
* which later may be used to continue 'readdir()'ing the directory or to
* 'seek()' to that specific direntry. Obviously UBIFS does not really fit this
* model because directory entries are identified by keys, which may collide.
*
* UBIFS uses directory entry hash value for directory offsets, so
* 'seekdir()'/'telldir()' may not always work because of possible key
* collisions. But UBIFS guarantees that consecutive 'readdir()' calls work
* properly by means of saving full directory entry name in the private field
* of the file description object.
*
* This means that UBIFS cannot support NFS which requires full
* 'seekdir()'/'telldir()' support.
*/
static int ubifs_readdir(struct file *file, struct dir_context *ctx)
{
int fstr_real_len = 0, err = 0;
struct fscrypt_name nm;
struct fscrypt_str fstr = {0};
union ubifs_key key;
struct ubifs_dent_node *dent;
struct inode *dir = file_inode(file);
struct ubifs_info *c = dir->i_sb->s_fs_info;
bool encrypted = ubifs_crypt_is_encrypted(dir);
dbg_gen("dir ino %lu, f_pos %#llx", dir->i_ino, ctx->pos);
if (ctx->pos > UBIFS_S_KEY_HASH_MASK || ctx->pos == 2)
/*
* The directory was seek'ed to a senseless position or there
* are no more entries.
*/
return 0;
if (encrypted) {
err = fscrypt_get_encryption_info(dir);
if (err && err != -ENOKEY)
return err;
err = fscrypt_fname_alloc_buffer(dir, UBIFS_MAX_NLEN, &fstr);
if (err)
return err;
fstr_real_len = fstr.len;
}
if (file->f_version == 0) {
/*
* The file was seek'ed, which means that @file->private_data
* is now invalid. This may also be just the first
* 'ubifs_readdir()' invocation, in which case
* @file->private_data is NULL, and the below code is
* basically a no-op.
*/
kfree(file->private_data);
file->private_data = NULL;
}
/*
* 'generic_file_llseek()' unconditionally sets @file->f_version to
* zero, and we use this for detecting whether the file was seek'ed.
*/
file->f_version = 1;
/* File positions 0 and 1 correspond to "." and ".." */
if (ctx->pos < 2) {
ubifs_assert(!file->private_data);
if (!dir_emit_dots(file, ctx)) {
if (encrypted)
fscrypt_fname_free_buffer(&fstr);
return 0;
}
/* Find the first entry in TNC and save it */
lowest_dent_key(c, &key, dir->i_ino);
fname_len(&nm) = 0;
dent = ubifs_tnc_next_ent(c, &key, &nm);
if (IS_ERR(dent)) {
err = PTR_ERR(dent);
goto out;
}
ctx->pos = key_hash_flash(c, &dent->key);
file->private_data = dent;
}
dent = file->private_data;
if (!dent) {
/*
* The directory was seek'ed to and is now readdir'ed.
* Find the entry corresponding to @ctx->pos or the closest one.
*/
dent_key_init_hash(c, &key, dir->i_ino, ctx->pos);
fname_len(&nm) = 0;
dent = ubifs_tnc_next_ent(c, &key, &nm);
if (IS_ERR(dent)) {
err = PTR_ERR(dent);
goto out;
}
ctx->pos = key_hash_flash(c, &dent->key);
file->private_data = dent;
}
while (1) {
dbg_gen("ino %llu, new f_pos %#x",
(unsigned long long)le64_to_cpu(dent->inum),
key_hash_flash(c, &dent->key));
ubifs_assert(le64_to_cpu(dent->ch.sqnum) >
ubifs_inode(dir)->creat_sqnum);
fname_len(&nm) = le16_to_cpu(dent->nlen);
fname_name(&nm) = dent->name;
if (encrypted) {
fstr.len = fstr_real_len;
err = fscrypt_fname_disk_to_usr(dir, key_hash_flash(c,
&dent->key),
le32_to_cpu(dent->cookie),
&nm.disk_name, &fstr);
if (err)
goto out;
} else {
fstr.len = fname_len(&nm);
fstr.name = fname_name(&nm);
}
if (!dir_emit(ctx, fstr.name, fstr.len,
le64_to_cpu(dent->inum),
vfs_dent_type(dent->type))) {
if (encrypted)
fscrypt_fname_free_buffer(&fstr);
return 0;
}
/* Switch to the next entry */
key_read(c, &dent->key, &key);
dent = ubifs_tnc_next_ent(c, &key, &nm);
if (IS_ERR(dent)) {
err = PTR_ERR(dent);
goto out;
}
kfree(file->private_data);
ctx->pos = key_hash_flash(c, &dent->key);
file->private_data = dent;
cond_resched();
}
out:
kfree(file->private_data);
file->private_data = NULL;
if (encrypted)
fscrypt_fname_free_buffer(&fstr);
if (err != -ENOENT)
ubifs_err(c, "cannot find next direntry, error %d", err);
else
/*
* -ENOENT is a non-fatal error in this context, the TNC uses
* it to indicate that the cursor moved past the current directory
* and readdir() has to stop.
*/
err = 0;
/* 2 is a special value indicating that there are no more direntries */
ctx->pos = 2;
return err;
}
/* Free saved readdir() state when the directory is closed */
static int ubifs_dir_release(struct inode *dir, struct file *file)
{
kfree(file->private_data);
file->private_data = NULL;
return 0;
}
/**
* lock_2_inodes - a wrapper for locking two UBIFS inodes.
* @inode1: first inode
* @inode2: second inode
*
* We do not implement any tricks to guarantee strict lock ordering, because
* VFS has already done it for us on the @i_mutex. So this is just a simple
* wrapper function.
*/
static void lock_2_inodes(struct inode *inode1, struct inode *inode2)
{
mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
}
/* support routines */
static int coda_venus_readdir(struct file *coda_file, struct dir_context *ctx)
{
struct coda_file_info *cfi;
struct coda_inode_info *cii;
struct file *host_file;
struct venus_dirent *vdir;
unsigned long vdir_size = offsetof(struct venus_dirent, d_name);
unsigned int type;
struct qstr name;
ino_t ino;
int ret;
cfi = CODA_FTOC(coda_file);
BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC);
host_file = cfi->cfi_container;
cii = ITOC(file_inode(coda_file));
vdir = kmalloc(sizeof(*vdir), GFP_KERNEL);
if (!vdir) return -ENOMEM;
if (!dir_emit_dots(coda_file, ctx))
goto out;
while (1) {
/* read entries from the directory file */
ret = kernel_read(host_file, ctx->pos - 2, (char *)vdir,
sizeof(*vdir));
if (ret < 0) {
pr_err("%s: read dir %s failed %d\n",
__func__, coda_f2s(&cii->c_fid), ret);
break;
}
if (ret == 0) break; /* end of directory file reached */
/* catch truncated reads */
if (ret < vdir_size || ret < vdir_size + vdir->d_namlen) {
pr_err("%s: short read on %s\n",
__func__, coda_f2s(&cii->c_fid));
ret = -EBADF;
break;
}
/* validate whether the directory file actually makes sense */
if (vdir->d_reclen < vdir_size + vdir->d_namlen) {
pr_err("%s: invalid dir %s\n",
__func__, coda_f2s(&cii->c_fid));
ret = -EBADF;
break;
}
name.len = vdir->d_namlen;
name.name = vdir->d_name;
/* Make sure we skip '.' and '..', we already got those */
if (name.name[0] == '.' && (name.len == 1 ||
(name.name[1] == '.' && name.len == 2)))
vdir->d_fileno = name.len = 0;
/* skip null entries */
if (vdir->d_fileno && name.len) {
ino = vdir->d_fileno;
type = CDT2DT(vdir->d_type);
if (!dir_emit(ctx, name.name, name.len, ino, type))
break;
}
/* we'll always have progress because d_reclen is unsigned and
* we've already established it is non-zero. */
ctx->pos += vdir->d_reclen;
}
out:
kfree(vdir);
return 0;
}
static int ubifs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
bool excl)
{
struct inode *inode;
struct ubifs_info *c = dir->i_sb->s_fs_info;
int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
.dirtied_ino = 1 };
struct ubifs_inode *dir_ui = ubifs_inode(dir);
/*
* Budget request settings: new inode, new direntry, changing the
* parent directory inode.
*/
dbg_gen("dent '%pd', mode %#hx in dir ino %lu",
dentry, mode, dir->i_ino);
err = ubifs_budget_space(c, &req);
if (err)
return err;
inode = ubifs_new_inode(c, dir, mode);
if (IS_ERR(inode)) {
err = PTR_ERR(inode);
goto out_budg;
}
err = ubifs_init_security(dir, inode, &dentry->d_name);
if (err)
goto out_inode;
mutex_lock(&dir_ui->ui_mutex);
dir->i_size += sz_change;
dir_ui->ui_size = dir->i_size;
dir->i_mtime = dir->i_ctime = inode->i_ctime;
err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
if (err)
goto out_cancel;
mutex_unlock(&dir_ui->ui_mutex);
ubifs_release_budget(c, &req);
insert_inode_hash(inode);
d_instantiate(dentry, inode);
return 0;
out_cancel:
dir->i_size -= sz_change;
dir_ui->ui_size = dir->i_size;
mutex_unlock(&dir_ui->ui_mutex);
out_inode:
make_bad_inode(inode);
iput(inode);
out_budg:
ubifs_release_budget(c, &req);
ubifs_err(c, "cannot create regular file, error %d", err);
return err;
}
/**
* vfs_dent_type - get VFS directory entry type.
* @type: UBIFS directory entry type
*
* This function converts UBIFS directory entry type into VFS directory entry
* type.
*/
static unsigned int vfs_dent_type(uint8_t type)
{
switch (type) {
case UBIFS_ITYPE_REG:
return DT_REG;
case UBIFS_ITYPE_DIR:
return DT_DIR;
case UBIFS_ITYPE_LNK:
return DT_LNK;
case UBIFS_ITYPE_BLK:
return DT_BLK;
case UBIFS_ITYPE_CHR:
return DT_CHR;
case UBIFS_ITYPE_FIFO:
return DT_FIFO;
case UBIFS_ITYPE_SOCK:
return DT_SOCK;
default:
BUG();
}
return 0;
}
/*
* The classical Unix view for directory is that it is a linear array of
* (name, inode number) entries. Linux/VFS assumes this model as well.
* Particularly, 'readdir()' call wants us to return a directory entry offset
* which later may be used to continue 'readdir()'ing the directory or to
* 'seek()' to that specific direntry. Obviously UBIFS does not really fit this
* model because directory entries are identified by keys, which may collide.
*
* UBIFS uses directory entry hash value for directory offsets, so
* 'seekdir()'/'telldir()' may not always work because of possible key
* collisions. But UBIFS guarantees that consecutive 'readdir()' calls work
* properly by means of saving full directory entry name in the private field
* of the file description object.
*
* This means that UBIFS cannot support NFS which requires full
* 'seekdir()'/'telldir()' support.
*/
static int ubifs_readdir(struct file *file, struct dir_context *ctx)
{
int err;
struct qstr nm;
union ubifs_key key;
struct ubifs_dent_node *dent;
struct inode *dir = file_inode(file);
struct ubifs_info *c = dir->i_sb->s_fs_info;
dbg_gen("dir ino %lu, f_pos %#llx", dir->i_ino, ctx->pos);
if (ctx->pos > UBIFS_S_KEY_HASH_MASK || ctx->pos == 2)
/*
* The directory was seek'ed to a senseless position or there
* are no more entries.
*/
return 0;
if (file->f_version == 0) {
/*
* The file was seek'ed, which means that @file->private_data
* is now invalid. This may also be just the first
* 'ubifs_readdir()' invocation, in which case
* @file->private_data is NULL, and the below code is
* basically a no-op.
*/
kfree(file->private_data);
file->private_data = NULL;
}
/*
* 'generic_file_llseek()' unconditionally sets @file->f_version to
* zero, and we use this for detecting whether the file was seek'ed.
*/
file->f_version = 1;
/* File positions 0 and 1 correspond to "." and ".." */
if (ctx->pos < 2) {
ubifs_assert(!file->private_data);
if (!dir_emit_dots(file, ctx))
return 0;
/* Find the first entry in TNC and save it */
lowest_dent_key(c, &key, dir->i_ino);
nm.name = NULL;
dent = ubifs_tnc_next_ent(c, &key, &nm);
if (IS_ERR(dent)) {
err = PTR_ERR(dent);
goto out;
}
ctx->pos = key_hash_flash(c, &dent->key);
file->private_data = dent;
}
dent = file->private_data;
if (!dent) {
/*
* The directory was seek'ed to and is now readdir'ed.
* Find the entry corresponding to @ctx->pos or the closest one.
*/
dent_key_init_hash(c, &key, dir->i_ino, ctx->pos);
nm.name = NULL;
dent = ubifs_tnc_next_ent(c, &key, &nm);
if (IS_ERR(dent)) {
err = PTR_ERR(dent);
goto out;
}
ctx->pos = key_hash_flash(c, &dent->key);
file->private_data = dent;
}
while (1) {
dbg_gen("feed '%s', ino %llu, new f_pos %#x",
dent->name, (unsigned long long)le64_to_cpu(dent->inum),
key_hash_flash(c, &dent->key));
ubifs_assert(le64_to_cpu(dent->ch.sqnum) >
ubifs_inode(dir)->creat_sqnum);
nm.len = le16_to_cpu(dent->nlen);
if (!dir_emit(ctx, dent->name, nm.len,
le64_to_cpu(dent->inum),
vfs_dent_type(dent->type)))
return 0;
/* Switch to the next entry */
key_read(c, &dent->key, &key);
nm.name = dent->name;
dent = ubifs_tnc_next_ent(c, &key, &nm);
if (IS_ERR(dent)) {
err = PTR_ERR(dent);
goto out;
}
kfree(file->private_data);
ctx->pos = key_hash_flash(c, &dent->key);
file->private_data = dent;
cond_resched();
}
out:
if (err != -ENOENT) {
ubifs_err(c, "cannot find next direntry, error %d", err);
return err;
}
kfree(file->private_data);
file->private_data = NULL;
/* 2 is a special value indicating that there are no more direntries */
ctx->pos = 2;
return 0;
}
static struct dentry *proc_ns_get_dentry(struct super_block *sb,
struct task_struct *task, const struct proc_ns_operations *ns_ops)
{
struct dentry *dentry, *result;
struct inode *inode;
struct proc_inode *ei;
struct qstr qname = { .name = "", };
void *ns;
ns = ns_ops->get(task);
if (!ns)
return ERR_PTR(-ENOENT);
dentry = d_alloc_pseudo(sb, &qname);
if (!dentry) {
ns_ops->put(ns);
return ERR_PTR(-ENOMEM);
}
inode = iget_locked(sb, ns_ops->inum(ns));
if (!inode) {
dput(dentry);
ns_ops->put(ns);
return ERR_PTR(-ENOMEM);
}
ei = PROC_I(inode);
if (inode->i_state & I_NEW) {
inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
inode->i_op = &ns_inode_operations;
inode->i_mode = S_IFREG | S_IRUGO;
inode->i_fop = &ns_file_operations;
ei->ns.ns_ops = ns_ops;
ei->ns.ns = ns;
unlock_new_inode(inode);
} else {
ns_ops->put(ns);
}
d_set_d_op(dentry, &ns_dentry_operations);
result = d_instantiate_unique(dentry, inode);
if (result) {
dput(dentry);
dentry = result;
}
return dentry;
}
static void *proc_ns_follow_link(struct dentry *dentry, struct nameidata *nd)
{
struct inode *inode = dentry->d_inode;
struct super_block *sb = inode->i_sb;
struct proc_inode *ei = PROC_I(inode);
struct task_struct *task;
struct path ns_path;
void *error = ERR_PTR(-EACCES);
task = get_proc_task(inode);
if (!task)
goto out;
if (!ptrace_may_access(task, PTRACE_MODE_READ))
goto out_put_task;
ns_path.dentry = proc_ns_get_dentry(sb, task, ei->ns.ns_ops);
if (IS_ERR(ns_path.dentry)) {
error = ERR_CAST(ns_path.dentry);
goto out_put_task;
}
ns_path.mnt = mntget(nd->path.mnt);
nd_jump_link(nd, &ns_path);
error = NULL;
out_put_task:
put_task_struct(task);
out:
return error;
}
static int proc_ns_readlink(struct dentry *dentry, char __user *buffer, int buflen)
{
struct inode *inode = dentry->d_inode;
struct proc_inode *ei = PROC_I(inode);
const struct proc_ns_operations *ns_ops = ei->ns.ns_ops;
struct task_struct *task;
void *ns;
char name[50];
int len = -EACCES;
task = get_proc_task(inode);
if (!task)
goto out;
if (!ptrace_may_access(task, PTRACE_MODE_READ))
goto out_put_task;
len = -ENOENT;
ns = ns_ops->get(task);
if (!ns)
goto out_put_task;
snprintf(name, sizeof(name), "%s:[%u]", ns_ops->name, ns_ops->inum(ns));
len = strlen(name);
if (len > buflen)
len = buflen;
if (copy_to_user(buffer, name, len))
len = -EFAULT;
ns_ops->put(ns);
out_put_task:
put_task_struct(task);
out:
return len;
}
static const struct inode_operations proc_ns_link_inode_operations = {
.readlink = proc_ns_readlink,
.follow_link = proc_ns_follow_link,
.setattr = proc_setattr,
};
static int proc_ns_instantiate(struct inode *dir,
struct dentry *dentry, struct task_struct *task, const void *ptr)
{
const struct proc_ns_operations *ns_ops = ptr;
struct inode *inode;
struct proc_inode *ei;
inode = proc_pid_make_inode(dir->i_sb, task);
if (!inode)
goto out;
ei = PROC_I(inode);
inode->i_mode = S_IFLNK|S_IRWXUGO;
inode->i_op = &proc_ns_link_inode_operations;
ei->ns.ns_ops = ns_ops;
d_set_d_op(dentry, &pid_dentry_operations);
d_add(dentry, inode);
/* Close the race of the process dying before we return the dentry */
if (pid_revalidate(dentry, 0))
return 0;
out:
return -ENOENT;
}
static int proc_ns_dir_readdir(struct file *file, struct dir_context *ctx)
{
struct task_struct *task = get_proc_task(file_inode(file));
const struct proc_ns_operations **entry, **last;
if (!task)
return -ENOENT;
if (!dir_emit_dots(file, ctx))
goto out;
if (ctx->pos >= 2 + ARRAY_SIZE(ns_entries))
goto out;
entry = ns_entries + (ctx->pos - 2);
last = &ns_entries[ARRAY_SIZE(ns_entries) - 1];
while (entry <= last) {
const struct proc_ns_operations *ops = *entry;
if (!proc_fill_cache(file, ctx, ops->name, strlen(ops->name),
proc_ns_instantiate, task, ops))
break;
ctx->pos++;
entry++;
}
out:
put_task_struct(task);
return 0;
}
const struct file_operations proc_ns_dir_operations = {
.read = generic_read_dir,
.iterate = proc_ns_dir_readdir,
};
static struct dentry *proc_ns_dir_lookup(struct inode *dir,
struct dentry *dentry, unsigned int flags)
{
int error;
struct task_struct *task = get_proc_task(dir);
const struct proc_ns_operations **entry, **last;
unsigned int len = dentry->d_name.len;
error = -ENOENT;
if (!task)
goto out_no_task;
last = &ns_entries[ARRAY_SIZE(ns_entries)];
for (entry = ns_entries; entry < last; entry++) {
if (strlen((*entry)->name) != len)
continue;
if (!memcmp(dentry->d_name.name, (*entry)->name, len))
break;
}
if (entry == last)
goto out;
error = proc_ns_instantiate(dir, dentry, task, *entry);
out:
put_task_struct(task);
out_no_task:
return ERR_PTR(error);
}
