[T106][ZXW-22]7520V3SCV2.01.01.02P42U09_VEC_V0.8_AP_VEC origin source commit
Change-Id: Ic6e05d89ecd62fc34f82b23dcf306c93764aec4b
diff --git a/ap/os/linux/linux-3.4.x/fs/notify/fsnotify.c b/ap/os/linux/linux-3.4.x/fs/notify/fsnotify.c
new file mode 100644
index 0000000..e5b6db6
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/fs/notify/fsnotify.c
@@ -0,0 +1,311 @@
+/*
+ * Copyright (C) 2008 Red Hat, Inc., Eric Paris <eparis@redhat.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING. If not, write to
+ * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/dcache.h>
+#include <linux/fs.h>
+#include <linux/gfp.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/mount.h>
+#include <linux/srcu.h>
+
+#include <linux/fsnotify_backend.h>
+#include "fsnotify.h"
+#include "../mount.h"
+
+/*
+ * Clear all of the marks on an inode when it is being evicted from core
+ */
+void __fsnotify_inode_delete(struct inode *inode)
+{
+ fsnotify_clear_marks_by_inode(inode);
+}
+EXPORT_SYMBOL_GPL(__fsnotify_inode_delete);
+
+void __fsnotify_vfsmount_delete(struct vfsmount *mnt)
+{
+ fsnotify_clear_marks_by_mount(mnt);
+}
+
+/*
+ * Given an inode, first check if we care what happens to our children. Inotify
+ * and dnotify both tell their parents about events. If we care about any event
+ * on a child we run all of our children and set a dentry flag saying that the
+ * parent cares. Thus when an event happens on a child it can quickly tell if
+ * if there is a need to find a parent and send the event to the parent.
+ */
+void __fsnotify_update_child_dentry_flags(struct inode *inode)
+{
+ struct dentry *alias;
+ int watched;
+
+ if (!S_ISDIR(inode->i_mode))
+ return;
+
+ /* determine if the children should tell inode about their events */
+ watched = fsnotify_inode_watches_children(inode);
+
+ spin_lock(&inode->i_lock);
+ /* run all of the dentries associated with this inode. Since this is a
+ * directory, there damn well better only be one item on this list */
+ list_for_each_entry(alias, &inode->i_dentry, d_u.d_alias) {
+ struct dentry *child;
+
+ /* run all of the children of the original inode and fix their
+ * d_flags to indicate parental interest (their parent is the
+ * original inode) */
+ spin_lock(&alias->d_lock);
+ list_for_each_entry(child, &alias->d_subdirs, d_child) {
+ if (!child->d_inode)
+ continue;
+
+ spin_lock_nested(&child->d_lock, DENTRY_D_LOCK_NESTED);
+ if (watched)
+ child->d_flags |= DCACHE_FSNOTIFY_PARENT_WATCHED;
+ else
+ child->d_flags &= ~DCACHE_FSNOTIFY_PARENT_WATCHED;
+ spin_unlock(&child->d_lock);
+ }
+ spin_unlock(&alias->d_lock);
+ }
+ spin_unlock(&inode->i_lock);
+}
+
+/* Notify this dentry's parent about a child's events. */
+int __fsnotify_parent(struct path *path, struct dentry *dentry, __u32 mask)
+{
+ struct dentry *parent;
+ struct inode *p_inode;
+ int ret = 0;
+
+ if (!dentry)
+ dentry = path->dentry;
+
+ if (!(dentry->d_flags & DCACHE_FSNOTIFY_PARENT_WATCHED))
+ return 0;
+
+ parent = dget_parent(dentry);
+ p_inode = parent->d_inode;
+
+ if (unlikely(!fsnotify_inode_watches_children(p_inode)))
+ __fsnotify_update_child_dentry_flags(p_inode);
+ else if (p_inode->i_fsnotify_mask & mask) {
+ /* we are notifying a parent so come up with the new mask which
+ * specifies these are events which came from a child. */
+ mask |= FS_EVENT_ON_CHILD;
+
+ if (path)
+ ret = fsnotify(p_inode, mask, path, FSNOTIFY_EVENT_PATH,
+ dentry->d_name.name, 0);
+ else
+ ret = fsnotify(p_inode, mask, dentry->d_inode, FSNOTIFY_EVENT_INODE,
+ dentry->d_name.name, 0);
+ }
+
+ dput(parent);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(__fsnotify_parent);
+
+static int send_to_group(struct inode *to_tell, struct vfsmount *mnt,
+ struct fsnotify_mark *inode_mark,
+ struct fsnotify_mark *vfsmount_mark,
+ __u32 mask, void *data,
+ int data_is, u32 cookie,
+ const unsigned char *file_name,
+ struct fsnotify_event **event)
+{
+ struct fsnotify_group *group = NULL;
+ __u32 inode_test_mask = 0;
+ __u32 vfsmount_test_mask = 0;
+
+ if (unlikely(!inode_mark && !vfsmount_mark)) {
+ BUG();
+ return 0;
+ }
+
+ /* clear ignored on inode modification */
+ if (mask & FS_MODIFY) {
+ if (inode_mark &&
+ !(inode_mark->flags & FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY))
+ inode_mark->ignored_mask = 0;
+ if (vfsmount_mark &&
+ !(vfsmount_mark->flags & FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY))
+ vfsmount_mark->ignored_mask = 0;
+ }
+
+ /* does the inode mark tell us to do something? */
+ if (inode_mark) {
+ group = inode_mark->group;
+ inode_test_mask = (mask & ~FS_EVENT_ON_CHILD);
+ inode_test_mask &= inode_mark->mask;
+ inode_test_mask &= ~inode_mark->ignored_mask;
+ }
+
+ /* does the vfsmount_mark tell us to do something? */
+ if (vfsmount_mark) {
+ vfsmount_test_mask = (mask & ~FS_EVENT_ON_CHILD);
+ group = vfsmount_mark->group;
+ vfsmount_test_mask &= vfsmount_mark->mask;
+ vfsmount_test_mask &= ~vfsmount_mark->ignored_mask;
+ if (inode_mark)
+ vfsmount_test_mask &= ~inode_mark->ignored_mask;
+ }
+
+ pr_debug("%s: group=%p to_tell=%p mnt=%p mask=%x inode_mark=%p"
+ " inode_test_mask=%x vfsmount_mark=%p vfsmount_test_mask=%x"
+ " data=%p data_is=%d cookie=%d event=%p\n",
+ __func__, group, to_tell, mnt, mask, inode_mark,
+ inode_test_mask, vfsmount_mark, vfsmount_test_mask, data,
+ data_is, cookie, *event);
+
+ if (!inode_test_mask && !vfsmount_test_mask)
+ return 0;
+
+ if (group->ops->should_send_event(group, to_tell, inode_mark,
+ vfsmount_mark, mask, data,
+ data_is) == false)
+ return 0;
+
+ if (!*event) {
+ *event = fsnotify_create_event(to_tell, mask, data,
+ data_is, file_name,
+ cookie, GFP_KERNEL);
+ if (!*event)
+ return -ENOMEM;
+ }
+ return group->ops->handle_event(group, inode_mark, vfsmount_mark, *event);
+}
+
+/*
+ * This is the main call to fsnotify. The VFS calls into hook specific functions
+ * in linux/fsnotify.h. Those functions then in turn call here. Here will call
+ * out to all of the registered fsnotify_group. Those groups can then use the
+ * notification event in whatever means they feel necessary.
+ */
+int fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is,
+ const unsigned char *file_name, u32 cookie)
+{
+ struct hlist_node *inode_node = NULL, *vfsmount_node = NULL;
+ struct fsnotify_mark *inode_mark = NULL, *vfsmount_mark = NULL;
+ struct fsnotify_group *inode_group, *vfsmount_group;
+ struct fsnotify_event *event = NULL;
+ struct mount *mnt;
+ int idx, ret = 0;
+ /* global tests shouldn't care about events on child only the specific event */
+ __u32 test_mask = (mask & ~FS_EVENT_ON_CHILD);
+
+ if (data_is == FSNOTIFY_EVENT_PATH)
+ mnt = real_mount(((struct path *)data)->mnt);
+ else
+ mnt = NULL;
+
+ /*
+ * if this is a modify event we may need to clear the ignored masks
+ * otherwise return if neither the inode nor the vfsmount care about
+ * this type of event.
+ */
+ if (!(mask & FS_MODIFY) &&
+ !(test_mask & to_tell->i_fsnotify_mask) &&
+ !(mnt && test_mask & mnt->mnt_fsnotify_mask))
+ return 0;
+
+ idx = srcu_read_lock(&fsnotify_mark_srcu);
+
+ if ((mask & FS_MODIFY) ||
+ (test_mask & to_tell->i_fsnotify_mask))
+ inode_node = srcu_dereference(to_tell->i_fsnotify_marks.first,
+ &fsnotify_mark_srcu);
+
+ if (mnt && ((mask & FS_MODIFY) ||
+ (test_mask & mnt->mnt_fsnotify_mask))) {
+ vfsmount_node = srcu_dereference(mnt->mnt_fsnotify_marks.first,
+ &fsnotify_mark_srcu);
+ inode_node = srcu_dereference(to_tell->i_fsnotify_marks.first,
+ &fsnotify_mark_srcu);
+ }
+
+ while (inode_node || vfsmount_node) {
+ inode_group = vfsmount_group = NULL;
+
+ if (inode_node) {
+ inode_mark = hlist_entry(srcu_dereference(inode_node, &fsnotify_mark_srcu),
+ struct fsnotify_mark, i.i_list);
+ inode_group = inode_mark->group;
+ }
+
+ if (vfsmount_node) {
+ vfsmount_mark = hlist_entry(srcu_dereference(vfsmount_node, &fsnotify_mark_srcu),
+ struct fsnotify_mark, m.m_list);
+ vfsmount_group = vfsmount_mark->group;
+ }
+
+ if (inode_group > vfsmount_group) {
+ /* handle inode */
+ ret = send_to_group(to_tell, NULL, inode_mark, NULL, mask, data,
+ data_is, cookie, file_name, &event);
+ /* we didn't use the vfsmount_mark */
+ vfsmount_group = NULL;
+ } else if (vfsmount_group > inode_group) {
+ ret = send_to_group(to_tell, &mnt->mnt, NULL, vfsmount_mark, mask, data,
+ data_is, cookie, file_name, &event);
+ inode_group = NULL;
+ } else {
+ ret = send_to_group(to_tell, &mnt->mnt, inode_mark, vfsmount_mark,
+ mask, data, data_is, cookie, file_name,
+ &event);
+ }
+
+ if (ret && (mask & ALL_FSNOTIFY_PERM_EVENTS))
+ goto out;
+
+ if (inode_group)
+ inode_node = srcu_dereference(inode_node->next,
+ &fsnotify_mark_srcu);
+ if (vfsmount_group)
+ vfsmount_node = srcu_dereference(vfsmount_node->next,
+ &fsnotify_mark_srcu);
+ }
+ ret = 0;
+out:
+ srcu_read_unlock(&fsnotify_mark_srcu, idx);
+ /*
+ * fsnotify_create_event() took a reference so the event can't be cleaned
+ * up while we are still trying to add it to lists, drop that one.
+ */
+ if (event)
+ fsnotify_put_event(event);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(fsnotify);
+
+static __init int fsnotify_init(void)
+{
+ int ret;
+
+ BUG_ON(hweight32(ALL_FSNOTIFY_EVENTS) != 23);
+
+ ret = init_srcu_struct(&fsnotify_mark_srcu);
+ if (ret)
+ panic("initializing fsnotify_mark_srcu");
+
+ return 0;
+}
+core_initcall(fsnotify_init);