vfs_intent-2.6-sles10.patch

非常经典的一个分布式系统

Index: LINUX-SRC-TREE/fs/9p/vfs_inode.c
===================================================================
--- LINUX-SRC-TREE.orig/fs/9p/vfs_inode.c
+++ LINUX-SRC-TREE/fs/9p/vfs_inode.c
@@ -469,7 +469,7 @@ v9fs_vfs_create(struct inode *dir, struc
 	perm = unixmode2p9mode(v9ses, mode);
 
 	if (nd && nd->flags & LOOKUP_OPEN)
-		flags = nd->intent.open.flags - 1;
+		flags = nd->intent.flags - 1;
 	else
 		flags = O_RDWR;
 
Index: LINUX-SRC-TREE/fs/cifs/dir.c
===================================================================
--- LINUX-SRC-TREE.orig/fs/cifs/dir.c
+++ LINUX-SRC-TREE/fs/cifs/dir.c
@@ -157,11 +157,7 @@ cifs_create(struct inode *inode, struct 
 
 #if LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0)
 	if(nd && (nd->flags & LOOKUP_OPEN)) {
-#if LINUX_VERSION_CODE == KERNEL_VERSION(2,6,5) /* SUSE included Lustre patch */
 		int oflags = nd->intent.it_flags;
-#else
-		int oflags = nd->intent.open.flags;
-#endif
 
 		desiredAccess = 0;
 		if (oflags & FMODE_READ)
Index: LINUX-SRC-TREE/fs/exec.c
===================================================================
--- LINUX-SRC-TREE.orig/fs/exec.c
+++ LINUX-SRC-TREE/fs/exec.c
@@ -129,7 +129,9 @@ asmlinkage long sys_uselib(const char __
 	struct nameidata nd;
 	int error;
 
-	error = __user_path_lookup_open(library, LOOKUP_FOLLOW, &nd, FMODE_READ);
+ 	intent_init(&nd.intent, IT_OPEN);
+	error = __user_path_lookup_open(library, LOOKUP_FOLLOW, &nd,
+					FMODE_READ | FMODE_EXEC);
 	if (error)
 		goto out;
 
@@ -481,7 +483,9 @@ struct file *open_exec(const char *name)
 	int err;
 	struct file *file;
 
-	err = path_lookup_open(AT_FDCWD, name, LOOKUP_FOLLOW, &nd, FMODE_READ);
+ 	intent_init(&nd.intent, IT_OPEN);
+	err = path_lookup_open(AT_FDCWD, name, LOOKUP_FOLLOW, &nd,
+			       FMODE_READ | FMODE_EXEC, 0);
 	file = ERR_PTR(err);
 
 	if (!err) {
@@ -1543,7 +1547,7 @@ int do_coredump(long signr, int exit_cod
 		goto close_fail;
 	if (!file->f_op->write)
 		goto close_fail;
-	if (do_truncate(file->f_dentry, 0, 0, file) != 0)
+	if (do_truncate(file->f_dentry, 0, 0, file, 0) != 0)
 		goto close_fail;
 
 	retval = binfmt->core_dump(signr, regs, file);
Index: LINUX-SRC-TREE/fs/fuse/dir.c
===================================================================
--- LINUX-SRC-TREE.orig/fs/fuse/dir.c
+++ LINUX-SRC-TREE/fs/fuse/dir.c
@@ -242,7 +242,7 @@ static int fuse_create_open(struct inode
 	struct fuse_entry_out outentry;
 	struct fuse_file *ff;
 	struct file *file;
-	int flags = nd->intent.open.flags - 1;
+	int flags = nd->intent.flags - 1;
 
 	err = -ENOSYS;
 	if (fc->no_create)
Index: LINUX-SRC-TREE/fs/inode.c
===================================================================
--- LINUX-SRC-TREE.orig/fs/inode.c
+++ LINUX-SRC-TREE/fs/inode.c
@@ -236,6 +236,7 @@ void __iget(struct inode * inode)
 	inodes_stat.nr_unused--;
 }
 
+EXPORT_SYMBOL(__iget);
 /**
  * clear_inode - clear an inode
  * @inode: inode to clear
Index: LINUX-SRC-TREE/fs/namei.c
===================================================================
--- LINUX-SRC-TREE.orig/fs/namei.c
+++ LINUX-SRC-TREE/fs/namei.c
@@ -337,8 +337,19 @@ int deny_write_access(struct file * file
 	return 0;
 }
 
+void intent_release(struct lookup_intent *it)
+{
+	if (!it)
+		return;
+	if (it->it_magic != INTENT_MAGIC)
+		return;
+	if (it->it_op_release)
+		it->it_op_release(it);
+}
+
 void path_release(struct nameidata *nd)
 {
+	intent_release(&nd->intent);
 	dput(nd->dentry);
 	mntput(nd->mnt);
 }
@@ -359,10 +370,10 @@ void path_release_on_umount(struct namei
  */
 void release_open_intent(struct nameidata *nd)
 {
-	if (nd->intent.open.file->f_dentry == NULL)
-		put_filp(nd->intent.open.file);
+	if (nd->intent.file->f_dentry == NULL)
+		put_filp(nd->intent.file);
 	else
-		fput(nd->intent.open.file);
+		fput(nd->intent.file);
 }
 
 /*
@@ -440,8 +451,12 @@ static struct dentry * real_lookup(struc
 {
 	struct dentry * result;
 	struct inode *dir = parent->d_inode;
+	int counter = 0;
 
 	mutex_lock(&dir->i_mutex);
+again:
+	counter++;
+
 	/*
 	 * First re-do the cached lookup just in case it was created
 	 * while we waited for the directory semaphore..
@@ -475,13 +490,16 @@ static struct dentry * real_lookup(struc
 	 * Uhhuh! Nasty case: the cache was re-populated while
 	 * we waited on the semaphore. Need to revalidate.
 	 */
-	mutex_unlock(&dir->i_mutex);
 	if (result->d_op && result->d_op->d_revalidate) {
 		if (!result->d_op->d_revalidate(result, nd) && !d_invalidate(result)) {
 			dput(result);
-			result = ERR_PTR(-ENOENT);
+			if (counter > 10)
+				result = ERR_PTR(-ESTALE);
+			if (!IS_ERR(result))
+				goto again;
 		}
 	}
+	mutex_unlock(&dir->i_mutex);
 	return result;
 }
 
@@ -510,6 +528,7 @@ static __always_inline int __vfs_follow_
 {
 	int res = 0;
 	char *name;
+
 	if (IS_ERR(link))
 		goto fail;
 
@@ -519,6 +538,7 @@ static __always_inline int __vfs_follow_
 			/* weird __emul_prefix() stuff did it */
 			goto out;
 	}
+	intent_reset_fs_part(&nd->intent);
 	res = link_path_walk(link, nd);
 out:
 	if (nd->depth || res || nd->last_type!=LAST_NORM)
@@ -768,6 +788,33 @@ fail:
 	return PTR_ERR(dentry);
 }
 
+static int revalidate_special(struct nameidata *nd)
+{
+	struct dentry *dentry = nd->dentry;
+	int err, counter = 0;
+
+ revalidate_again:
+	if (!dentry->d_op || !dentry->d_op->d_revalidate)
+		return 0;
+	if (!dentry->d_op->d_revalidate(dentry, nd)) {
+		struct dentry *new;
+		if ((err = permission(dentry->d_parent->d_inode, MAY_EXEC, nd)))
+			return err;
+		new = real_lookup(dentry->d_parent, &dentry->d_name, nd);
+		if (IS_ERR(new))
+			return PTR_ERR(new);
+		d_invalidate(dentry);
+		dput(dentry);
+		nd->dentry = dentry = new;
+		counter++;
+		if (counter < 10)
+			goto revalidate_again;
+		printk("excessive revalidate_it loops\n");
+		return -ESTALE;
+	}
+	return 0;
+}
+
 /*
  * Name resolution.
  * This is the basic name resolution function, turning a pathname into
@@ -864,7 +911,11 @@ static fastcall int __link_path_walk(con
 			goto out_dput;
 
 		if (inode->i_op->follow_link) {
+			int save_flags = nd->flags;
+			nd->flags |= LOOKUP_LINK_NOTLAST;
 			err = do_follow_link(&next, nd);
+			if (!(save_flags & LOOKUP_LINK_NOTLAST))
+				nd->flags &= ~LOOKUP_LINK_NOTLAST;
 			if (err)
 				goto return_err;
 			err = -ENOENT;
@@ -899,6 +950,23 @@ last_component:
 				inode = nd->dentry->d_inode;
 				/* fallthrough */
 			case 1:
+				nd->flags |= LOOKUP_LAST;
+				err = revalidate_special(nd);
+				nd->flags &= ~LOOKUP_LAST;
+				if (!nd->dentry->d_inode)
+					err = -ENOENT;
+				if (err) {
+					path_release(nd);
+					goto return_err;
+				}
+				if (lookup_flags & LOOKUP_DIRECTORY) {
+					err = -ENOTDIR;
+					if(!nd->dentry->d_inode->i_op ||
+					  !nd->dentry->d_inode->i_op->lookup) {
+						path_release(nd);
+						goto return_err;
+					}
+				}
 				goto return_reval;
 		}
 		if (nd->dentry->d_op && nd->dentry->d_op->d_hash) {
@@ -906,7 +974,9 @@ last_component:
 			if (err < 0)
 				break;
 		}
+		nd->flags |= LOOKUP_LAST;
 		err = do_lookup(nd, &this, &next);
+		nd->flags &= ~LOOKUP_LAST;
 		if (err)
 			break;
 		inode = next.dentry->d_inode;
@@ -1066,7 +1136,7 @@ set_it:
 }
 
 /* Returns 0 and nd will be valid on success; Retuns error, otherwise. */
-static int fastcall do_path_lookup(int dfd, const char *name,
+static int fastcall do_path_lookup_it(int dfd, const char *name,
 				unsigned int flags, struct nameidata *nd)
 {
 	int retval = 0;
@@ -1134,10 +1204,23 @@ fput_fail:
 	goto out_fail;
 }
 
-int fastcall path_lookup(const char *name, unsigned int flags,
+static int fastcall do_path_lookup(int dfd, const char *name,
+				unsigned int flags, struct nameidata *nd)
+{
+	intent_init(&nd->intent, IT_GETATTR);
+	return do_path_lookup_it(dfd, name, flags, nd);
+}
+
+int fastcall path_lookup_it(const char *name, unsigned int flags,
 			struct nameidata *nd)
 {
-	return do_path_lookup(AT_FDCWD, name, flags, nd);
+	return do_path_lookup_it(AT_FDCWD, name, flags, nd);
+}
+
+int fastcall path_lookup(const char *name, unsigned int flags, struct nameidata *nd)
+{
+	intent_init(&nd->intent, IT_GETATTR);
+	return path_lookup_it(name, flags, nd);
 }
 
 static int __path_lookup_intent_open(int dfd, const char *name,
@@ -1149,13 +1232,13 @@ static int __path_lookup_intent_open(int
 
 	if (filp == NULL)
 		return -ENFILE;
-	nd->intent.open.file = filp;
-	nd->intent.open.flags = open_flags;
-	nd->intent.open.create_mode = create_mode;
-	err = do_path_lookup(dfd, name, lookup_flags|LOOKUP_OPEN, nd);
-	if (IS_ERR(nd->intent.open.file)) {
+	nd->intent.file = filp;
+	nd->intent.flags = open_flags;
+	nd->intent.create_mode = create_mode;
+	err = do_path_lookup_it(dfd, name, lookup_flags|LOOKUP_OPEN, nd);
+	if (IS_ERR(nd->intent.file)) {
 		if (err == 0) {
-			err = PTR_ERR(nd->intent.open.file);
+			err = PTR_ERR(nd->intent.file);
 			path_release(nd);
 		}
 	} else if (err != 0)
@@ -1172,10 +1255,10 @@ static int __path_lookup_intent_open(int
  * @open_flags: open intent flags
  */
 int path_lookup_open(int dfd, const char *name, unsigned int lookup_flags,
-		struct nameidata *nd, int open_flags)
+		struct nameidata *nd, int open_flags, int create_mode)
 {
 	return __path_lookup_intent_open(dfd, name, lookup_flags, nd,
-			open_flags, 0);
+			open_flags, create_mode);
 }
 
 /**
@@ -1258,7 +1341,7 @@ struct dentry * lookup_hash(struct namei
 }
 
 /* SMP-safe */
-struct dentry * lookup_one_len(const char * name, struct dentry * base, int len)
+struct dentry * lookup_one_len_it(const char * name, struct dentry * base, int len, struct nameidata *nd)
 {
 	unsigned long hash;
 	struct qstr this;
@@ -1278,11 +1361,17 @@ struct dentry * lookup_one_len(const cha
 	}
 	this.hash = end_name_hash(hash);
 
-	return __lookup_hash(&this, base, NULL);
+	return __lookup_hash(&this, base, nd);
 access:
 	return ERR_PTR(-EACCES);
 }
 
+struct dentry * lookup_one_len(const char * name, struct dentry * base, int len)
+{
+ 	return lookup_one_len_it(name, base, len, NULL);
+}
+
+
 /*
  *	namei()
  *
@@ -1294,22 +1383,36 @@ access:
  * that namei follows links, while lnamei does not.
  * SMP-safe
  */
-int fastcall __user_walk_fd(int dfd, const char __user *name, unsigned flags,
-			    struct nameidata *nd)
+
+int fastcall __user_walk_fd_it(int dfd, const char __user *name, unsigned flags,
+			       struct nameidata *nd)
 {
 	char *tmp = getname(name);
 	int err = PTR_ERR(tmp);
 
 	if (!IS_ERR(tmp)) {
-		err = do_path_lookup(dfd, tmp, flags, nd);
+		err = do_path_lookup_it(dfd, tmp, flags, nd);
 		putname(tmp);
 	}
 	return err;
 }
 
+int fastcall __user_walk_fd(int dfd, const char __user *name, unsigned flags,
+			    struct nameidata *nd)
+{
+	intent_init(&nd->intent, IT_LOOKUP);