struct t4_debugfs_entry {
const char *name;
const struct file_operations *ops;
- mode_t mode;
+ umode_t mode;
unsigned char data;
};
dentry, dentry, dentry->d_parent,
dentry->d_inode, dentry->d_flags);
- if (unlikely(dentry == dentry->d_sb->s_root)) {
- CERROR("%s: called on root dentry=%p, fid="DFID"\n",
- ll_get_fsname(dentry->d_sb, NULL, 0),
- dentry, PFID(ll_inode2fid(inode)));
- lustre_dump_dentry(dentry, 1);
- dump_stack();
- }
-
d_lustre_invalidate(dentry, 0);
}
ll_unlock_dcache(inode);
void ll_dirty_page_discard_warn(struct page *page, int ioret);
int ll_prep_inode(struct inode **inode, struct ptlrpc_request *req,
struct super_block *, struct lookup_intent *);
-void lustre_dump_dentry(struct dentry *, int recur);
int ll_obd_statfs(struct inode *inode, void *arg);
int ll_get_max_mdsize(struct ll_sb_info *sbi, int *max_mdsize);
int ll_get_default_mdsize(struct ll_sb_info *sbi, int *default_mdsize);
return rc;
}
-static void ll_dump_inode(struct inode *inode)
-{
- struct ll_d_hlist_node *tmp;
- int dentry_count = 0;
-
- LASSERT(inode != NULL);
-
- ll_d_hlist_for_each(tmp, &inode->i_dentry)
- dentry_count++;
-
- CERROR("inode %p dump: dev=%s ino=%lu mode=%o count=%u, %d dentries\n",
- inode, ll_i2mdexp(inode)->exp_obd->obd_name, inode->i_ino,
- inode->i_mode, atomic_read(&inode->i_count), dentry_count);
-}
-
-void lustre_dump_dentry(struct dentry *dentry, int recur)
-{
- struct list_head *tmp;
- int subdirs = 0;
-
- LASSERT(dentry != NULL);
-
- list_for_each(tmp, &dentry->d_subdirs)
- subdirs++;
-
- CERROR("dentry %p dump: name=%pd parent=%pd (%p), inode=%p, count=%u, flags=0x%x, fsdata=%p, %d subdirs\n",
- dentry, dentry, dentry->d_parent, dentry->d_parent,
- dentry->d_inode, d_count(dentry),
- dentry->d_flags, dentry->d_fsdata, subdirs);
- if (dentry->d_inode != NULL)
- ll_dump_inode(dentry->d_inode);
-
- if (recur == 0)
- return;
-
- list_for_each(tmp, &dentry->d_subdirs) {
- struct dentry *d = list_entry(tmp, struct dentry, d_child);
-
- lustre_dump_dentry(d, recur - 1);
- }
-}
-
static void client_common_put_super(struct super_block *sb)
{
struct ll_sb_info *sbi = ll_s2sbi(sb);
* dentry_iput drops the locks, at which point nobody (except
* transient RCU lookups) can reach this dentry.
*/
- BUG_ON((int)dentry->d_lockref.count > 0);
+ BUG_ON(dentry->d_lockref.count > 0);
this_cpu_dec(nr_dentry);
if (dentry->d_op && dentry->d_op->d_release)
dentry->d_op->d_release(dentry);
struct dentry *parent = dentry->d_parent;
if (IS_ROOT(dentry))
return NULL;
- if (unlikely((int)dentry->d_lockref.count < 0))
+ if (unlikely(dentry->d_lockref.count < 0))
return NULL;
if (likely(spin_trylock(&parent->d_lock)))
return parent;
return parent;
}
+/*
+ * Try to do a lockless dput(), and return whether that was successful.
+ *
+ * If unsuccessful, we return false, having already taken the dentry lock.
+ *
+ * The caller needs to hold the RCU read lock, so that the dentry is
+ * guaranteed to stay around even if the refcount goes down to zero!
+ */
+static inline bool fast_dput(struct dentry *dentry)
+{
+ int ret;
+ unsigned int d_flags;
+
+ /*
+ * If we have a d_op->d_delete() operation, we sould not
+ * let the dentry count go to zero, so use "put__or_lock".
+ */
+ if (unlikely(dentry->d_flags & DCACHE_OP_DELETE))
+ return lockref_put_or_lock(&dentry->d_lockref);
+
+ /*
+ * .. otherwise, we can try to just decrement the
+ * lockref optimistically.
+ */
+ ret = lockref_put_return(&dentry->d_lockref);
+
+ /*
+ * If the lockref_put_return() failed due to the lock being held
+ * by somebody else, the fast path has failed. We will need to
+ * get the lock, and then check the count again.
+ */
+ if (unlikely(ret < 0)) {
+ spin_lock(&dentry->d_lock);
+ if (dentry->d_lockref.count > 1) {
+ dentry->d_lockref.count--;
+ spin_unlock(&dentry->d_lock);
+ return 1;
+ }
+ return 0;
+ }
+
+ /*
+ * If we weren't the last ref, we're done.
+ */
+ if (ret)
+ return 1;
+
+ /*
+ * Careful, careful. The reference count went down
+ * to zero, but we don't hold the dentry lock, so
+ * somebody else could get it again, and do another
+ * dput(), and we need to not race with that.
+ *
+ * However, there is a very special and common case
+ * where we don't care, because there is nothing to
+ * do: the dentry is still hashed, it does not have
+ * a 'delete' op, and it's referenced and already on
+ * the LRU list.
+ *
+ * NOTE! Since we aren't locked, these values are
+ * not "stable". However, it is sufficient that at
+ * some point after we dropped the reference the
+ * dentry was hashed and the flags had the proper
+ * value. Other dentry users may have re-gotten
+ * a reference to the dentry and change that, but
+ * our work is done - we can leave the dentry
+ * around with a zero refcount.
+ */
+ smp_rmb();
+ d_flags = ACCESS_ONCE(dentry->d_flags);
+ d_flags &= DCACHE_REFERENCED | DCACHE_LRU_LIST;
+
+ /* Nothing to do? Dropping the reference was all we needed? */
+ if (d_flags == (DCACHE_REFERENCED | DCACHE_LRU_LIST) && !d_unhashed(dentry))
+ return 1;
+
+ /*
+ * Not the fast normal case? Get the lock. We've already decremented
+ * the refcount, but we'll need to re-check the situation after
+ * getting the lock.
+ */
+ spin_lock(&dentry->d_lock);
+
+ /*
+ * Did somebody else grab a reference to it in the meantime, and
+ * we're no longer the last user after all? Alternatively, somebody
+ * else could have killed it and marked it dead. Either way, we
+ * don't need to do anything else.
+ */
+ if (dentry->d_lockref.count) {
+ spin_unlock(&dentry->d_lock);
+ return 1;
+ }
+
+ /*
+ * Re-get the reference we optimistically dropped. We hold the
+ * lock, and we just tested that it was zero, so we can just
+ * set it to 1.
+ */
+ dentry->d_lockref.count = 1;
+ return 0;
+}
+
+
/*
* This is dput
*
return;
repeat:
- if (lockref_put_or_lock(&dentry->d_lockref))
+ rcu_read_lock();
+ if (likely(fast_dput(dentry))) {
+ rcu_read_unlock();
return;
+ }
+
+ /* Slow case: now with the dentry lock held */
+ rcu_read_unlock();
/* Unreachable? Get rid of it */
if (unlikely(d_unhashed(dentry)))
* We found an inuse dentry which was not removed from
* the LRU because of laziness during lookup. Do not free it.
*/
- if ((int)dentry->d_lockref.count > 0) {
+ if (dentry->d_lockref.count > 0) {
spin_unlock(&dentry->d_lock);
if (parent)
spin_unlock(&parent->d_lock);
}
EXPORT_SYMBOL(d_hash_and_lookup);
-/**
- * d_validate - verify dentry provided from insecure source (deprecated)
- * @dentry: The dentry alleged to be valid child of @dparent
- * @dparent: The parent dentry (known to be valid)
- *
- * An insecure source has sent us a dentry, here we verify it and dget() it.
- * This is used by ncpfs in its readdir implementation.
- * Zero is returned in the dentry is invalid.
- *
- * This function is slow for big directories, and deprecated, do not use it.
- */
-int d_validate(struct dentry *dentry, struct dentry *dparent)
-{
- struct dentry *child;
-
- spin_lock(&dparent->d_lock);
- list_for_each_entry(child, &dparent->d_subdirs, d_child) {
- if (dentry == child) {
- spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED);
- __dget_dlock(dentry);
- spin_unlock(&dentry->d_lock);
- spin_unlock(&dparent->d_lock);
- return 1;
- }
- }
- spin_unlock(&dparent->d_lock);
-
- return 0;
-}
-EXPORT_SYMBOL(d_validate);
-
/*
* When a file is deleted, we have two options:
* - turn this dentry into a negative dentry
#include <linux/fs.h>
+#include <linux/sched.h>
#include <linux/slab.h>
-#include <linux/fs_pin.h>
#include "internal.h"
#include "mount.h"
-static void pin_free_rcu(struct rcu_head *head)
-{
- kfree(container_of(head, struct fs_pin, rcu));
-}
-
static DEFINE_SPINLOCK(pin_lock);
-void pin_put(struct fs_pin *p)
-{
- if (atomic_long_dec_and_test(&p->count))
- call_rcu(&p->rcu, pin_free_rcu);
-}
-
void pin_remove(struct fs_pin *pin)
{
spin_lock(&pin_lock);
hlist_del(&pin->m_list);
hlist_del(&pin->s_list);
spin_unlock(&pin_lock);
+ spin_lock_irq(&pin->wait.lock);
+ pin->done = 1;
+ wake_up_locked(&pin->wait);
+ spin_unlock_irq(&pin->wait.lock);
}
-void pin_insert(struct fs_pin *pin, struct vfsmount *m)
+void pin_insert_group(struct fs_pin *pin, struct vfsmount *m, struct hlist_head *p)
{
spin_lock(&pin_lock);
- hlist_add_head(&pin->s_list, &m->mnt_sb->s_pins);
+ if (p)
+ hlist_add_head(&pin->s_list, p);
hlist_add_head(&pin->m_list, &real_mount(m)->mnt_pins);
spin_unlock(&pin_lock);
}
+void pin_insert(struct fs_pin *pin, struct vfsmount *m)
+{
+ pin_insert_group(pin, m, &m->mnt_sb->s_pins);
+}
+
+void pin_kill(struct fs_pin *p)
+{
+ wait_queue_t wait;
+
+ if (!p) {
+ rcu_read_unlock();
+ return;
+ }
+ init_wait(&wait);
+ spin_lock_irq(&p->wait.lock);
+ if (likely(!p->done)) {
+ p->done = -1;
+ spin_unlock_irq(&p->wait.lock);
+ rcu_read_unlock();
+ p->kill(p);
+ return;
+ }
+ if (p->done > 0) {
+ spin_unlock_irq(&p->wait.lock);
+ rcu_read_unlock();
+ return;
+ }
+ __add_wait_queue(&p->wait, &wait);
+ while (1) {
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ spin_unlock_irq(&p->wait.lock);
+ rcu_read_unlock();
+ schedule();
+ rcu_read_lock();
+ if (likely(list_empty(&wait.task_list)))
+ break;
+ /* OK, we know p couldn't have been freed yet */
+ spin_lock_irq(&p->wait.lock);
+ if (p->done > 0) {
+ spin_unlock_irq(&p->wait.lock);
+ break;
+ }
+ }
+ rcu_read_unlock();
+}
+
void mnt_pin_kill(struct mount *m)
{
while (1) {
struct hlist_node *p;
- struct fs_pin *pin;
rcu_read_lock();
p = ACCESS_ONCE(m->mnt_pins.first);
if (!p) {
rcu_read_unlock();
break;
}
- pin = hlist_entry(p, struct fs_pin, m_list);
- if (!atomic_long_inc_not_zero(&pin->count)) {
- rcu_read_unlock();
- cpu_relax();
- continue;
- }
- rcu_read_unlock();
- pin->kill(pin);
+ pin_kill(hlist_entry(p, struct fs_pin, m_list));
}
}
-void sb_pin_kill(struct super_block *sb)
+void group_pin_kill(struct hlist_head *p)
{
while (1) {
- struct hlist_node *p;
- struct fs_pin *pin;
+ struct hlist_node *q;
rcu_read_lock();
- p = ACCESS_ONCE(sb->s_pins.first);
- if (!p) {
+ q = ACCESS_ONCE(p->first);
+ if (!q) {
rcu_read_unlock();
break;
}
- pin = hlist_entry(p, struct fs_pin, s_list);
- if (!atomic_long_inc_not_zero(&pin->count)) {
- rcu_read_unlock();
- cpu_relax();
- continue;
- }
- rcu_read_unlock();
- pin->kill(pin);
+ pin_kill(hlist_entry(q, struct fs_pin, s_list));
}
}
/*
* fs_pin.c
*/
-extern void sb_pin_kill(struct super_block *sb);
+extern void group_pin_kill(struct hlist_head *p);
extern void mnt_pin_kill(struct mount *m);
/*
#include <linux/seq_file.h>
#include <linux/poll.h>
#include <linux/ns_common.h>
+#include <linux/fs_pin.h>
struct mnt_namespace {
atomic_t count;
int mnt_group_id; /* peer group identifier */
int mnt_expiry_mark; /* true if marked for expiry */
struct hlist_head mnt_pins;
- struct path mnt_ex_mountpoint;
+ struct fs_pin mnt_umount;
+ struct dentry *mnt_ex_mountpoint;
};
#define MNT_NS_INTERNAL ERR_PTR(-EINVAL) /* distinct from any mnt_namespace */
#endif
}
+static void drop_mountpoint(struct fs_pin *p)
+{
+ struct mount *m = container_of(p, struct mount, mnt_umount);
+ dput(m->mnt_ex_mountpoint);
+ pin_remove(p);
+ mntput(&m->mnt);
+}
+
static struct mount *alloc_vfsmnt(const char *name)
{
struct mount *mnt = kmem_cache_zalloc(mnt_cache, GFP_KERNEL);
#ifdef CONFIG_FSNOTIFY
INIT_HLIST_HEAD(&mnt->mnt_fsnotify_marks);
#endif
+ init_fs_pin(&mnt->mnt_umount, drop_mountpoint);
}
return mnt;
static void namespace_unlock(void)
{
- struct mount *mnt;
struct hlist_head head = unmounted;
if (likely(hlist_empty(&head))) {
head.first->pprev = &head.first;
INIT_HLIST_HEAD(&unmounted);
-
- /* undo decrements we'd done in umount_tree() */
- hlist_for_each_entry(mnt, &head, mnt_hash)
- if (mnt->mnt_ex_mountpoint.mnt)
- mntget(mnt->mnt_ex_mountpoint.mnt);
-
up_write(&namespace_sem);
synchronize_rcu();
- while (!hlist_empty(&head)) {
- mnt = hlist_entry(head.first, struct mount, mnt_hash);
- hlist_del_init(&mnt->mnt_hash);
- if (mnt->mnt_ex_mountpoint.mnt)
- path_put(&mnt->mnt_ex_mountpoint);
- mntput(&mnt->mnt);
- }
+ group_pin_kill(&head);
}
static inline void namespace_lock(void)
{
HLIST_HEAD(tmp_list);
struct mount *p;
- struct mount *last = NULL;
for (p = mnt; p; p = next_mnt(p, mnt)) {
hlist_del_init_rcu(&p->mnt_hash);
if (how)
propagate_umount(&tmp_list);
- hlist_for_each_entry(p, &tmp_list, mnt_hash) {
+ while (!hlist_empty(&tmp_list)) {
+ p = hlist_entry(tmp_list.first, struct mount, mnt_hash);
+ hlist_del_init_rcu(&p->mnt_hash);
list_del_init(&p->mnt_expire);
list_del_init(&p->mnt_list);
__touch_mnt_namespace(p->mnt_ns);
p->mnt_ns = NULL;
if (how < 2)
p->mnt.mnt_flags |= MNT_SYNC_UMOUNT;
+
+ pin_insert_group(&p->mnt_umount, &p->mnt_parent->mnt, &unmounted);
if (mnt_has_parent(p)) {
hlist_del_init(&p->mnt_mp_list);
put_mountpoint(p->mnt_mp);
mnt_add_count(p->mnt_parent, -1);
- /* move the reference to mountpoint into ->mnt_ex_mountpoint */
- p->mnt_ex_mountpoint.dentry = p->mnt_mountpoint;
- p->mnt_ex_mountpoint.mnt = &p->mnt_parent->mnt;
+ /* old mountpoint will be dropped when we can do that */
+ p->mnt_ex_mountpoint = p->mnt_mountpoint;
p->mnt_mountpoint = p->mnt.mnt_root;
p->mnt_parent = p;
p->mnt_mp = NULL;
}
change_mnt_propagation(p, MS_PRIVATE);
- last = p;
- }
- if (last) {
- last->mnt_hash.next = unmounted.first;
- if (unmounted.first)
- unmounted.first->pprev = &last->mnt_hash.next;
- unmounted.first = tmp_list.first;
- unmounted.first->pprev = &unmounted.first;
}
}
static int ncp_compare_dentry(const struct dentry *, const struct dentry *,
unsigned int, const char *, const struct qstr *);
static int ncp_delete_dentry(const struct dentry *);
+static void ncp_d_prune(struct dentry *dentry);
const struct dentry_operations ncp_dentry_operations =
{
.d_hash = ncp_hash_dentry,
.d_compare = ncp_compare_dentry,
.d_delete = ncp_delete_dentry,
+ .d_prune = ncp_d_prune,
};
#define ncp_namespace(i) (NCP_SERVER(i)->name_space[NCP_FINFO(i)->volNumber])
return val;
}
-static struct dentry *
-ncp_dget_fpos(struct dentry *dentry, struct dentry *parent, unsigned long fpos)
-{
- struct dentry *dent = dentry;
-
- if (d_validate(dent, parent)) {
- if (dent->d_name.len <= NCP_MAXPATHLEN &&
- (unsigned long)dent->d_fsdata == fpos) {
- if (!dent->d_inode) {
- dput(dent);
- dent = NULL;
- }
- return dent;
- }
- dput(dent);
- }
-
- /* If a pointer is invalid, we search the dentry. */
- spin_lock(&parent->d_lock);
- list_for_each_entry(dent, &parent->d_subdirs, d_child) {
- if ((unsigned long)dent->d_fsdata == fpos) {
- if (dent->d_inode)
- dget(dent);
- else
- dent = NULL;
- spin_unlock(&parent->d_lock);
- goto out;
- }
- }
- spin_unlock(&parent->d_lock);
- return NULL;
-
-out:
- return dent;
-}
-
static time_t ncp_obtain_mtime(struct dentry *dentry)
{
struct inode *inode = dentry->d_inode;
return ncp_date_dos2unix(i.modifyTime, i.modifyDate);
}
+static inline void
+ncp_invalidate_dircache_entries(struct dentry *parent)
+{
+ struct ncp_server *server = NCP_SERVER(parent->d_inode);
+ struct dentry *dentry;
+
+ spin_lock(&parent->d_lock);
+ list_for_each_entry(dentry, &parent->d_subdirs, d_child) {
+ dentry->d_fsdata = NULL;
+ ncp_age_dentry(server, dentry);
+ }
+ spin_unlock(&parent->d_lock);
+}
+
static int ncp_readdir(struct file *file, struct dir_context *ctx)
{
struct dentry *dentry = file->f_path.dentry;
struct dentry *dent;
bool over;
- dent = ncp_dget_fpos(ctl.cache->dentry[ctl.idx],
- dentry, ctx->pos);
- if (!dent)
+ spin_lock(&dentry->d_lock);
+ if (!(NCP_FINFO(inode)->flags & NCPI_DIR_CACHE)) {
+ spin_unlock(&dentry->d_lock);
+ goto invalid_cache;
+ }
+ dent = ctl.cache->dentry[ctl.idx];
+ if (unlikely(!lockref_get_not_dead(&dent->d_lockref))) {
+ spin_unlock(&dentry->d_lock);
+ goto invalid_cache;
+ }
+ spin_unlock(&dentry->d_lock);
+ if (!dent->d_inode) {
+ dput(dent);
goto invalid_cache;
+ }
over = !dir_emit(ctx, dent->d_name.name,
dent->d_name.len,
dent->d_inode->i_ino, DT_UNKNOWN);
ctl.filled = 0;
ctl.valid = 1;
read_really:
+ spin_lock(&dentry->d_lock);
+ NCP_FINFO(inode)->flags |= NCPI_DIR_CACHE;
+ spin_unlock(&dentry->d_lock);
if (ncp_is_server_root(inode)) {
ncp_read_volume_list(file, ctx, &ctl);
} else {
return result;
}
+static void ncp_d_prune(struct dentry *dentry)
+{
+ if (!dentry->d_fsdata) /* not referenced from page cache */
+ return;
+ NCP_FINFO(dentry->d_parent->d_inode)->flags &= ~NCPI_DIR_CACHE;
+}
+
static int
ncp_fill_cache(struct file *file, struct dir_context *ctx,
struct ncp_cache_control *ctrl, struct ncp_entry_info *entry,
d_instantiate(newdent, inode);
if (!hashed)
d_rehash(newdent);
+ } else {
+ spin_lock(&dentry->d_lock);
+ NCP_FINFO(inode)->flags &= ~NCPI_DIR_CACHE;
+ spin_unlock(&dentry->d_lock);
}
} else {
struct inode *inode = newdent->d_inode;
mutex_unlock(&inode->i_mutex);
}
- if (newdent->d_inode) {
- ino = newdent->d_inode->i_ino;
- newdent->d_fsdata = (void *) ctl.fpos;
- ncp_new_dentry(newdent);
- }
-
if (ctl.idx >= NCP_DIRCACHE_SIZE) {
if (ctl.page) {
kunmap(ctl.page);
ctl.cache = kmap(ctl.page);
}
if (ctl.cache) {
- ctl.cache->dentry[ctl.idx] = newdent;
- valid = 1;
+ if (newdent->d_inode) {
+ newdent->d_fsdata = newdent;
+ ctl.cache->dentry[ctl.idx] = newdent;
+ ino = newdent->d_inode->i_ino;
+ ncp_new_dentry(newdent);
+ }
+ valid = 1;
}
dput(newdent);
end_advance:
int access;
int flags;
#define NCPI_KLUDGE_SYMLINK 0x0001
+#define NCPI_DIR_CACHE 0x0002
__u8 file_handle[6];
struct inode vfs_inode;
};
dentry->d_time = jiffies;
}
-static inline void
-ncp_renew_dentries(struct dentry *parent)
-{
- struct ncp_server *server = NCP_SERVER(parent->d_inode);
- struct dentry *dentry;
-
- spin_lock(&parent->d_lock);
- list_for_each_entry(dentry, &parent->d_subdirs, d_child) {
- if (dentry->d_fsdata == NULL)
- ncp_age_dentry(server, dentry);
- else
- ncp_new_dentry(dentry);
- }
- spin_unlock(&parent->d_lock);
-}
-
-static inline void
-ncp_invalidate_dircache_entries(struct dentry *parent)
-{
- struct ncp_server *server = NCP_SERVER(parent->d_inode);
- struct dentry *dentry;
-
- spin_lock(&parent->d_lock);
- list_for_each_entry(dentry, &parent->d_subdirs, d_child) {
- dentry->d_fsdata = NULL;
- ncp_age_dentry(server, dentry);
- }
- spin_unlock(&parent->d_lock);
-}
-
struct ncp_cache_head {
time_t mtime;
unsigned long time; /* cache age */
if (ret)
return ret;
- if (S_ISDIR(dp->mode)) {
- dp->proc_fops = &proc_dir_operations;
- dp->proc_iops = &proc_dir_inode_operations;
- dir->nlink++;
- } else if (S_ISLNK(dp->mode)) {
- dp->proc_iops = &proc_link_inode_operations;
- } else if (S_ISREG(dp->mode)) {
- BUG_ON(dp->proc_fops == NULL);
- dp->proc_iops = &proc_file_inode_operations;
- } else {
- WARN_ON(1);
- proc_free_inum(dp->low_ino);
- return -EINVAL;
- }
-
spin_lock(&proc_subdir_lock);
dp->parent = dir;
if (pde_subdir_insert(dir, dp) == false) {
WARN(1, "proc_dir_entry '%s/%s' already registered\n",
dir->name, dp->name);
spin_unlock(&proc_subdir_lock);
- if (S_ISDIR(dp->mode))
- dir->nlink--;
proc_free_inum(dp->low_ino);
return -EEXIST;
}
ent->data = kmalloc((ent->size=strlen(dest))+1, GFP_KERNEL);
if (ent->data) {
strcpy((char*)ent->data,dest);
+ ent->proc_iops = &proc_link_inode_operations;
if (proc_register(parent, ent) < 0) {
kfree(ent->data);
kfree(ent);
ent = __proc_create(&parent, name, S_IFDIR | mode, 2);
if (ent) {
ent->data = data;
+ ent->proc_fops = &proc_dir_operations;
+ ent->proc_iops = &proc_dir_inode_operations;
+ parent->nlink++;
if (proc_register(parent, ent) < 0) {
kfree(ent);
+ parent->nlink--;
ent = NULL;
}
}
return NULL;
}
+ BUG_ON(proc_fops == NULL);
+
if ((mode & S_IALLUGO) == 0)
mode |= S_IRUGO;
pde = __proc_create(&parent, name, mode, 1);
goto out;
pde->proc_fops = proc_fops;
pde->data = data;
+ pde->proc_iops = &proc_file_inode_operations;
if (proc_register(parent, pde) < 0)
goto out_free;
return pde;
remount_ro = (flags & MS_RDONLY) && !(sb->s_flags & MS_RDONLY);
if (remount_ro) {
- if (sb->s_pins.first) {
+ if (!hlist_empty(&sb->s_pins)) {
up_write(&sb->s_umount);
- sb_pin_kill(sb);
+ group_pin_kill(&sb->s_pins);
down_write(&sb->s_umount);
if (!sb->s_root)
return 0;
return dentry->d_lockref.count;
}
-/* validate "insecure" dentry pointer */
-extern int d_validate(struct dentry *, struct dentry *);
-
/*
* helper function for dentry_operations.d_dname() members
*/
-#include <linux/fs.h>
+#include <linux/wait.h>
struct fs_pin {
- atomic_long_t count;
- union {
- struct {
- struct hlist_node s_list;
- struct hlist_node m_list;
- };
- struct rcu_head rcu;
- };
+ wait_queue_head_t wait;
+ int done;
+ struct hlist_node s_list;
+ struct hlist_node m_list;
void (*kill)(struct fs_pin *);
};
-void pin_put(struct fs_pin *);
+struct vfsmount;
+
+static inline void init_fs_pin(struct fs_pin *p, void (*kill)(struct fs_pin *))
+{
+ init_waitqueue_head(&p->wait);
+ p->kill = kill;
+}
+
void pin_remove(struct fs_pin *);
+void pin_insert_group(struct fs_pin *, struct vfsmount *, struct hlist_head *);
void pin_insert(struct fs_pin *, struct vfsmount *);
+void pin_kill(struct fs_pin *);
#endif
struct {
spinlock_t lock;
- unsigned int count;
+ int count;
};
};
};
extern void lockref_get(struct lockref *);
+extern int lockref_put_return(struct lockref *);
extern int lockref_get_not_zero(struct lockref *);
extern int lockref_get_or_lock(struct lockref *);
extern int lockref_put_or_lock(struct lockref *);
#define BITS_PER_PAGE_MASK (BITS_PER_PAGE-1)
#define PIDMAP_ENTRIES ((PID_MAX_LIMIT+BITS_PER_PAGE-1)/BITS_PER_PAGE)
-struct bsd_acct_struct;
+struct fs_pin;
struct pid_namespace {
struct kref kref;
struct dentry *proc_thread_self;
#endif
#ifdef CONFIG_BSD_PROCESS_ACCT
- struct bsd_acct_struct *bacct;
+ struct fs_pin *bacct;
#endif
struct user_namespace *user_ns;
struct work_struct proc_work;
/*
* External references and all of the globals.
*/
-static void do_acct_process(struct bsd_acct_struct *acct);
struct bsd_acct_struct {
struct fs_pin pin;
+ atomic_long_t count;
+ struct rcu_head rcu;
struct mutex lock;
int active;
unsigned long needcheck;
struct completion done;
};
+static void do_acct_process(struct bsd_acct_struct *acct);
+
/*
* Check the amount of free space and suspend/resume accordingly.
*/
return acct->active;
}
+static void acct_put(struct bsd_acct_struct *p)
+{
+ if (atomic_long_dec_and_test(&p->count))
+ kfree_rcu(p, rcu);
+}
+
+static inline struct bsd_acct_struct *to_acct(struct fs_pin *p)
+{
+ return p ? container_of(p, struct bsd_acct_struct, pin) : NULL;
+}
+
static struct bsd_acct_struct *acct_get(struct pid_namespace *ns)
{
struct bsd_acct_struct *res;
again:
smp_rmb();
rcu_read_lock();
- res = ACCESS_ONCE(ns->bacct);
+ res = to_acct(ACCESS_ONCE(ns->bacct));
if (!res) {
rcu_read_unlock();
return NULL;
}
- if (!atomic_long_inc_not_zero(&res->pin.count)) {
+ if (!atomic_long_inc_not_zero(&res->count)) {
rcu_read_unlock();
cpu_relax();
goto again;
}
rcu_read_unlock();
mutex_lock(&res->lock);
- if (!res->ns) {
+ if (res != to_acct(ACCESS_ONCE(ns->bacct))) {
mutex_unlock(&res->lock);
- pin_put(&res->pin);
+ acct_put(res);
goto again;
}
return res;
}
+static void acct_pin_kill(struct fs_pin *pin)
+{
+ struct bsd_acct_struct *acct = to_acct(pin);
+ mutex_lock(&acct->lock);
+ do_acct_process(acct);
+ schedule_work(&acct->work);
+ wait_for_completion(&acct->done);
+ cmpxchg(&acct->ns->bacct, pin, NULL);
+ mutex_unlock(&acct->lock);
+ pin_remove(pin);
+ acct_put(acct);
+}
+
static void close_work(struct work_struct *work)
{
struct bsd_acct_struct *acct = container_of(work, struct bsd_acct_struct, work);
complete(&acct->done);
}
-static void acct_kill(struct bsd_acct_struct *acct,
- struct bsd_acct_struct *new)
-{
- if (acct) {
- struct pid_namespace *ns = acct->ns;
- do_acct_process(acct);
- INIT_WORK(&acct->work, close_work);
- init_completion(&acct->done);
- schedule_work(&acct->work);
- wait_for_completion(&acct->done);
- pin_remove(&acct->pin);
- ns->bacct = new;
- acct->ns = NULL;
- atomic_long_dec(&acct->pin.count);
- mutex_unlock(&acct->lock);
- pin_put(&acct->pin);
- }
-}
-
-static void acct_pin_kill(struct fs_pin *pin)
-{
- struct bsd_acct_struct *acct;
- acct = container_of(pin, struct bsd_acct_struct, pin);
- mutex_lock(&acct->lock);
- if (!acct->ns) {
- mutex_unlock(&acct->lock);
- pin_put(pin);
- acct = NULL;
- }
- acct_kill(acct, NULL);
-}
-
static int acct_on(struct filename *pathname)
{
struct file *file;
struct vfsmount *mnt, *internal;
struct pid_namespace *ns = task_active_pid_ns(current);
- struct bsd_acct_struct *acct, *old;
+ struct bsd_acct_struct *acct;
+ struct fs_pin *old;
int err;
acct = kzalloc(sizeof(struct bsd_acct_struct), GFP_KERNEL);
mnt = file->f_path.mnt;
file->f_path.mnt = internal;
- atomic_long_set(&acct->pin.count, 1);
- acct->pin.kill = acct_pin_kill;
+ atomic_long_set(&acct->count, 1);
+ init_fs_pin(&acct->pin, acct_pin_kill);
acct->file = file;
acct->needcheck = jiffies;
acct->ns = ns;
mutex_init(&acct->lock);
+ INIT_WORK(&acct->work, close_work);
+ init_completion(&acct->done);
mutex_lock_nested(&acct->lock, 1); /* nobody has seen it yet */
pin_insert(&acct->pin, mnt);
- old = acct_get(ns);
- if (old)
- acct_kill(old, acct);
- else
- ns->bacct = acct;
+ rcu_read_lock();
+ old = xchg(&ns->bacct, &acct->pin);
mutex_unlock(&acct->lock);
+ pin_kill(old);
mnt_drop_write(mnt);
mntput(mnt);
return 0;
mutex_unlock(&acct_on_mutex);
putname(tmp);
} else {
- acct_kill(acct_get(task_active_pid_ns(current)), NULL);
+ rcu_read_lock();
+ pin_kill(task_active_pid_ns(current)->bacct);
}
return error;
void acct_exit_ns(struct pid_namespace *ns)
{
- acct_kill(acct_get(ns), NULL);
+ rcu_read_lock();
+ pin_kill(ns->bacct);
}
/*
if (acct) {
do_acct_process(acct);
mutex_unlock(&acct->lock);
- pin_put(&acct->pin);
+ acct_put(acct);
}
}
}
struct audit_aux_data_bprm_fcaps *ax;
struct audit_context *context = current->audit_context;
struct cpu_vfs_cap_data vcaps;
- struct dentry *dentry;
ax = kmalloc(sizeof(*ax), GFP_KERNEL);
if (!ax)
ax->d.next = context->aux;
context->aux = (void *)ax;
- dentry = dget(bprm->file->f_path.dentry);
- get_vfs_caps_from_disk(dentry, &vcaps);
- dput(dentry);
+ get_vfs_caps_from_disk(bprm->file->f_path.dentry, &vcaps);
ax->fcap.permitted = vcaps.permitted;
ax->fcap.inheritable = vcaps.inheritable;
EXPORT_SYMBOL(lockref_get);
/**
- * lockref_get_not_zero - Increments count unless the count is 0
+ * lockref_get_not_zero - Increments count unless the count is 0 or dead
* @lockref: pointer to lockref structure
* Return: 1 if count updated successfully or 0 if count was zero
*/
CMPXCHG_LOOP(
new.count++;
- if (!old.count)
+ if (old.count <= 0)
return 0;
,
return 1;
spin_lock(&lockref->lock);
retval = 0;
- if (lockref->count) {
+ if (lockref->count > 0) {
lockref->count++;
retval = 1;
}
EXPORT_SYMBOL(lockref_get_not_zero);
/**
- * lockref_get_or_lock - Increments count unless the count is 0
+ * lockref_get_or_lock - Increments count unless the count is 0 or dead
* @lockref: pointer to lockref structure
* Return: 1 if count updated successfully or 0 if count was zero
* and we got the lock instead.
{
CMPXCHG_LOOP(
new.count++;
- if (!old.count)
+ if (old.count <= 0)
break;
,
return 1;
);
spin_lock(&lockref->lock);
- if (!lockref->count)
+ if (lockref->count <= 0)
return 0;
lockref->count++;
spin_unlock(&lockref->lock);
}
EXPORT_SYMBOL(lockref_get_or_lock);
+/**
+ * lockref_put_return - Decrement reference count if possible
+ * @lockref: pointer to lockref structure
+ *
+ * Decrement the reference count and return the new value.
+ * If the lockref was dead or locked, return an error.
+ */
+int lockref_put_return(struct lockref *lockref)
+{
+ CMPXCHG_LOOP(
+ new.count--;
+ if (old.count <= 0)
+ return -1;
+ ,
+ return new.count;
+ );
+ return -1;
+}
+EXPORT_SYMBOL(lockref_put_return);
+
/**
* lockref_put_or_lock - decrements count unless count <= 1 before decrement
* @lockref: pointer to lockref structure
CMPXCHG_LOOP(
new.count++;
- if ((int)old.count < 0)
+ if (old.count < 0)
return 0;
,
return 1;
spin_lock(&lockref->lock);
retval = 0;
- if ((int) lockref->count >= 0) {
+ if (lockref->count >= 0) {
lockref->count++;
retval = 1;
}
*/
static int get_file_caps(struct linux_binprm *bprm, bool *effective, bool *has_cap)
{
- struct dentry *dentry;
int rc = 0;
struct cpu_vfs_cap_data vcaps;
if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
return 0;
- dentry = dget(bprm->file->f_path.dentry);
-
- rc = get_vfs_caps_from_disk(dentry, &vcaps);
+ rc = get_vfs_caps_from_disk(bprm->file->f_path.dentry, &vcaps);
if (rc < 0) {
if (rc == -EINVAL)
printk(KERN_NOTICE "%s: get_vfs_caps_from_disk returned %d for %s\n",
__func__, rc, bprm->filename);
out:
- dput(dentry);
if (rc)
bprm_clear_caps(bprm);
static void sel_remove_entries(struct dentry *de)
{
- struct list_head *node;
-
- spin_lock(&de->d_lock);
- node = de->d_subdirs.next;
- while (node != &de->d_subdirs) {
- struct dentry *d = list_entry(node, struct dentry, d_child);
-
- spin_lock_nested(&d->d_lock, DENTRY_D_LOCK_NESTED);
- list_del_init(node);
-
- if (d->d_inode) {
- dget_dlock(d);
- spin_unlock(&de->d_lock);
- spin_unlock(&d->d_lock);
- d_delete(d);
- simple_unlink(de->d_inode, d);
- dput(d);
- spin_lock(&de->d_lock);
- } else
- spin_unlock(&d->d_lock);
- node = de->d_subdirs.next;
- }
-
- spin_unlock(&de->d_lock);
+ d_genocide(de);
+ shrink_dcache_parent(de);
}
#define BOOL_DIR_NAME "booleans"
return rc;
}
-static void sel_remove_classes(void)
-{
- struct list_head *class_node;
-
- list_for_each(class_node, &class_dir->d_subdirs) {
- struct dentry *class_subdir = list_entry(class_node,
- struct dentry, d_child);
- struct list_head *class_subdir_node;
-
- list_for_each(class_subdir_node, &class_subdir->d_subdirs) {
- struct dentry *d = list_entry(class_subdir_node,
- struct dentry, d_child);
-
- if (d->d_inode)
- if (d->d_inode->i_mode & S_IFDIR)
- sel_remove_entries(d);
- }
-
- sel_remove_entries(class_subdir);
- }
-
- sel_remove_entries(class_dir);
-}
-
static int sel_make_classes(void)
{
int rc, nclasses, i;
char **classes;
/* delete any existing entries */
- sel_remove_classes();
+ sel_remove_entries(class_dir);
rc = security_get_classes(&classes, &nclasses);
if (rc)
projects / linux-drm-fsl-dcu.git / commitdiff