#include <linux/security.h>
#include <linux/mount.h>
#include <linux/ramfs.h>
+#include <linux/log2.h>
#include <asm/uaccess.h>
#include <asm/unistd.h>
#include "pnode.h"
#include "internal.h"
+#define HASH_SHIFT ilog2(PAGE_SIZE / sizeof(struct list_head))
+#define HASH_SIZE (1UL << HASH_SHIFT)
+
/* spinlock for vfsmount related operations, inplace of dcache_lock */
__cacheline_aligned_in_smp DEFINE_SPINLOCK(vfsmount_lock);
static int event;
static struct list_head *mount_hashtable __read_mostly;
-static int hash_mask __read_mostly, hash_bits __read_mostly;
static struct kmem_cache *mnt_cache __read_mostly;
static struct rw_semaphore namespace_sem;
/* /sys/fs */
-decl_subsys(fs, NULL, NULL);
-EXPORT_SYMBOL_GPL(fs_subsys);
+struct kobject *fs_kobj;
+EXPORT_SYMBOL_GPL(fs_kobj);
static inline unsigned long hash(struct vfsmount *mnt, struct dentry *dentry)
{
unsigned long tmp = ((unsigned long)mnt / L1_CACHE_BYTES);
tmp += ((unsigned long)dentry / L1_CACHE_BYTES);
- tmp = tmp + (tmp >> hash_bits);
- return tmp & hash_mask;
+ tmp = tmp + (tmp >> HASH_SHIFT);
+ return tmp & (HASH_SIZE - 1);
}
struct vfsmount *alloc_vfsmnt(const char *name)
list_add(&mnt->mnt_slave, &old->mnt_slave_list);
mnt->mnt_master = old;
CLEAR_MNT_SHARED(mnt);
- } else {
+ } else if (!(flag & CL_PRIVATE)) {
if ((flag & CL_PROPAGATION) || IS_MNT_SHARED(old))
list_add(&mnt->mnt_share, &old->mnt_share);
if (IS_MNT_SLAVE(old))
EXPORT_SYMBOL(mnt_unpin);
+static inline void mangle(struct seq_file *m, const char *s)
+{
+ seq_escape(m, s, " \t\n\\");
+}
+
+/*
+ * Simple .show_options callback for filesystems which don't want to
+ * implement more complex mount option showing.
+ *
+ * See also save_mount_options().
+ */
+int generic_show_options(struct seq_file *m, struct vfsmount *mnt)
+{
+ const char *options = mnt->mnt_sb->s_options;
+
+ if (options != NULL && options[0]) {
+ seq_putc(m, ',');
+ mangle(m, options);
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(generic_show_options);
+
+/*
+ * If filesystem uses generic_show_options(), this function should be
+ * called from the fill_super() callback.
+ *
+ * The .remount_fs callback usually needs to be handled in a special
+ * way, to make sure, that previous options are not overwritten if the
+ * remount fails.
+ *
+ * Also note, that if the filesystem's .remount_fs function doesn't
+ * reset all options to their default value, but changes only newly
+ * given options, then the displayed options will not reflect reality
+ * any more.
+ */
+void save_mount_options(struct super_block *sb, char *options)
+{
+ kfree(sb->s_options);
+ sb->s_options = kstrdup(options, GFP_KERNEL);
+}
+EXPORT_SYMBOL(save_mount_options);
+
/* iterator */
static void *m_start(struct seq_file *m, loff_t *pos)
{
up_read(&namespace_sem);
}
-static inline void mangle(struct seq_file *m, const char *s)
-{
- seq_escape(m, s, " \t\n\\");
-}
-
static int show_vfsmnt(struct seq_file *m, void *v)
{
struct vfsmount *mnt = list_entry(v, struct vfsmount, mnt_list);
return NULL;
}
+struct vfsmount *collect_mounts(struct vfsmount *mnt, struct dentry *dentry)
+{
+ struct vfsmount *tree;
+ down_read(&namespace_sem);
+ tree = copy_tree(mnt, dentry, CL_COPY_ALL | CL_PRIVATE);
+ up_read(&namespace_sem);
+ return tree;
+}
+
+void drop_collected_mounts(struct vfsmount *mnt)
+{
+ LIST_HEAD(umount_list);
+ down_read(&namespace_sem);
+ spin_lock(&vfsmount_lock);
+ umount_tree(mnt, 0, &umount_list);
+ spin_unlock(&vfsmount_lock);
+ up_read(&namespace_sem);
+ release_mounts(&umount_list);
+}
+
/*
* @source_mnt : mount tree to be attached
* @nd : place the mount tree @source_mnt is attached
/*
* recursively change the type of the mountpoint.
+ * noinline this do_mount helper to save do_mount stack space.
*/
-static int do_change_type(struct nameidata *nd, int flag)
+static noinline int do_change_type(struct nameidata *nd, int flag)
{
struct vfsmount *m, *mnt = nd->mnt;
int recurse = flag & MS_REC;
/*
* do loopback mount.
+ * noinline this do_mount helper to save do_mount stack space.
*/
-static int do_loopback(struct nameidata *nd, char *old_name, int recurse)
+static noinline int do_loopback(struct nameidata *nd, char *old_name,
+ int recurse)
{
struct nameidata old_nd;
struct vfsmount *mnt = NULL;
* change filesystem flags. dir should be a physical root of filesystem.
* If you've mounted a non-root directory somewhere and want to do remount
* on it - tough luck.
+ * noinline this do_mount helper to save do_mount stack space.
*/
-static int do_remount(struct nameidata *nd, int flags, int mnt_flags,
+static noinline int do_remount(struct nameidata *nd, int flags, int mnt_flags,
void *data)
{
int err;
return 0;
}
-static int do_move_mount(struct nameidata *nd, char *old_name)
+/*
+ * noinline this do_mount helper to save do_mount stack space.
+ */
+static noinline int do_move_mount(struct nameidata *nd, char *old_name)
{
struct nameidata old_nd, parent_nd;
struct vfsmount *p;
/*
* create a new mount for userspace and request it to be added into the
* namespace's tree
+ * noinline this do_mount helper to save do_mount stack space.
*/
-static int do_new_mount(struct nameidata *nd, char *type, int flags,
+static noinline int do_new_mount(struct nameidata *nd, char *type, int flags,
int mnt_flags, char *name, void *data)
{
struct vfsmount *mnt;
mnt_flags |= MNT_RELATIME;
flags &= ~(MS_NOSUID | MS_NOEXEC | MS_NODEV | MS_ACTIVE |
- MS_NOATIME | MS_NODIRATIME | MS_RELATIME);
+ MS_NOATIME | MS_NODIRATIME | MS_RELATIME| MS_KERNMOUNT);
/* ... and get the mountpoint */
retval = path_lookup(dir_name, LOOKUP_FOLLOW, &nd);
void __init mnt_init(void)
{
- struct list_head *d;
- unsigned int nr_hash;
- int i;
+ unsigned u;
int err;
init_rwsem(&namespace_sem);
if (!mount_hashtable)
panic("Failed to allocate mount hash table\n");
- /*
- * Find the power-of-two list-heads that can fit into the allocation..
- * We don't guarantee that "sizeof(struct list_head)" is necessarily
- * a power-of-two.
- */
- nr_hash = PAGE_SIZE / sizeof(struct list_head);
- hash_bits = 0;
- do {
- hash_bits++;
- } while ((nr_hash >> hash_bits) != 0);
- hash_bits--;
+ printk("Mount-cache hash table entries: %lu\n", HASH_SIZE);
+
+ for (u = 0; u < HASH_SIZE; u++)
+ INIT_LIST_HEAD(&mount_hashtable[u]);
- /*
- * Re-calculate the actual number of entries and the mask
- * from the number of bits we can fit.
- */
- nr_hash = 1UL << hash_bits;
- hash_mask = nr_hash - 1;
-
- printk("Mount-cache hash table entries: %d\n", nr_hash);
-
- /* And initialize the newly allocated array */
- d = mount_hashtable;
- i = nr_hash;
- do {
- INIT_LIST_HEAD(d);
- d++;
- i--;
- } while (i);
err = sysfs_init();
if (err)
printk(KERN_WARNING "%s: sysfs_init error: %d\n",
__FUNCTION__, err);
- err = subsystem_register(&fs_subsys);
- if (err)
- printk(KERN_WARNING "%s: subsystem_register error: %d\n",
- __FUNCTION__, err);
+ fs_kobj = kobject_create_and_add("fs", NULL);
+ if (!fs_kobj)
+ printk(KERN_WARNING "%s: kobj create error\n", __FUNCTION__);
init_rootfs();
init_mount_tree();
}
projects / linux-2.6-omap-h63xx.git / blobdiff