Merge branch 'vfs-scale-working' of git://git.kernel.org/pub/scm/linux/kernel/git/npiggin/linux-npiggin

* 'vfs-scale-working' of git://git.kernel.org/pub/scm/linux/kernel/git/npiggin/linux-npiggin: (57 commits)
  fs: scale mntget/mntput
  fs: rename vfsmount counter helpers
  fs: implement faster dentry memcmp
  fs: prefetch inode data in dcache lookup
  fs: improve scalability of pseudo filesystems
  fs: dcache per-inode inode alias locking
  fs: dcache per-bucket dcache hash locking
  bit_spinlock: add required includes
  kernel: add bl_list
  xfs: provide simple rcu-walk ACL implementation
  btrfs: provide simple rcu-walk ACL implementation
  ext2,3,4: provide simple rcu-walk ACL implementation
  fs: provide simple rcu-walk generic_check_acl implementation
  fs: provide rcu-walk aware permission i_ops
  fs: rcu-walk aware d_revalidate method
  fs: cache optimise dentry and inode for rcu-walk
  fs: dcache reduce branches in lookup path
  fs: dcache remove d_mounted
  fs: fs_struct use seqlock
  fs: rcu-walk for path lookup
  ...

10 files changed, 48 insertions, 24 deletions

diff --git a/fs/gfs2/acl.c b/fs/gfs2/acl.c
index 48171f4c943d..7118f1a780a9 100644
--- a/fs/gfs2/acl.c
+++ b/fs/gfs2/acl.c
@@ -75,11 +75,14 @@ static struct posix_acl *gfs2_acl_get(struct gfs2_inode *ip, int type)
  * Returns: errno
  */
 
-int gfs2_check_acl(struct inode *inode, int mask)
+int gfs2_check_acl(struct inode *inode, int mask, unsigned int flags)
 {
         struct posix_acl *acl;
         int error;
 
+        if (flags & IPERM_FLAG_RCU)
+                return -ECHILD;
+
         acl = gfs2_acl_get(GFS2_I(inode), ACL_TYPE_ACCESS);
         if (IS_ERR(acl))
                 return PTR_ERR(acl);
diff --git a/fs/gfs2/acl.h b/fs/gfs2/acl.h
index b522b0cb39ea..a93907c8159b 100644
--- a/fs/gfs2/acl.h
+++ b/fs/gfs2/acl.h
@@ -16,7 +16,7 @@
 #define GFS2_POSIX_ACL_DEFAULT          "posix_acl_default"
 #define GFS2_ACL_MAX_ENTRIES            25
 
-extern int gfs2_check_acl(struct inode *inode, int mask);
+extern int gfs2_check_acl(struct inode *inode, int mask, unsigned int);
 extern int gfs2_acl_create(struct gfs2_inode *dip, struct inode *inode);
 extern int gfs2_acl_chmod(struct gfs2_inode *ip, struct iattr *attr);
 extern const struct xattr_handler gfs2_xattr_system_handler;
diff --git a/fs/gfs2/dentry.c b/fs/gfs2/dentry.c
index 6798755b3858..4a456338b873 100644
--- a/fs/gfs2/dentry.c
+++ b/fs/gfs2/dentry.c
@@ -11,6 +11,7 @@
 #include <linux/completion.h>
 #include <linux/buffer_head.h>
 #include <linux/gfs2_ondisk.h>
+#include <linux/namei.h>
 #include <linux/crc32.h>
 
 #include "gfs2.h"
@@ -34,15 +35,23 @@
 
 static int gfs2_drevalidate(struct dentry *dentry, struct nameidata *nd)
 {
-        struct dentry *parent = dget_parent(dentry);
-        struct gfs2_sbd *sdp = GFS2_SB(parent->d_inode);
-        struct gfs2_inode *dip = GFS2_I(parent->d_inode);
-        struct inode *inode = dentry->d_inode;
+        struct dentry *parent;
+        struct gfs2_sbd *sdp;
+        struct gfs2_inode *dip;
+        struct inode *inode;
         struct gfs2_holder d_gh;
         struct gfs2_inode *ip = NULL;
         int error;
         int had_lock = 0;
 
+        if (nd->flags & LOOKUP_RCU)
+                return -ECHILD;
+
+        parent = dget_parent(dentry);
+        sdp = GFS2_SB(parent->d_inode);
+        dip = GFS2_I(parent->d_inode);
+        inode = dentry->d_inode;
+
         if (inode) {
                 if (is_bad_inode(inode))
                         goto invalid;
@@ -100,13 +109,14 @@ fail:
         return 0;
 }
 
-static int gfs2_dhash(struct dentry *dentry, struct qstr *str)
+static int gfs2_dhash(const struct dentry *dentry, const struct inode *inode,
+                struct qstr *str)
 {
         str->hash = gfs2_disk_hash(str->name, str->len);
         return 0;
 }
 
-static int gfs2_dentry_delete(struct dentry *dentry)
+static int gfs2_dentry_delete(const struct dentry *dentry)
 {
         struct gfs2_inode *ginode;
 
diff --git a/fs/gfs2/export.c b/fs/gfs2/export.c
index 5ab3839dfcb9..97012ecff560 100644
--- a/fs/gfs2/export.c
+++ b/fs/gfs2/export.c
@@ -130,7 +130,7 @@ static struct dentry *gfs2_get_parent(struct dentry *child)
 
         dentry = d_obtain_alias(gfs2_lookupi(child->d_inode, &gfs2_qdotdot, 1));
         if (!IS_ERR(dentry))
-                dentry->d_op = &gfs2_dops;
+                d_set_d_op(dentry, &gfs2_dops);
         return dentry;
 }
 
@@ -158,7 +158,7 @@ static struct dentry *gfs2_get_dentry(struct super_block *sb,
 out_inode:
         dentry = d_obtain_alias(inode);
         if (!IS_ERR(dentry))
-                dentry->d_op = &gfs2_dops;
+                d_set_d_op(dentry, &gfs2_dops);
         return dentry;
 }
 
diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c
index aa996471ec5c..fca6689e12e6 100644
--- a/fs/gfs2/file.c
+++ b/fs/gfs2/file.c
@@ -241,7 +241,7 @@ static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask)
             !capable(CAP_LINUX_IMMUTABLE))
                 goto out;
         if (!IS_IMMUTABLE(inode)) {
-                error = gfs2_permission(inode, MAY_WRITE);
+                error = gfs2_permission(inode, MAY_WRITE, 0);
                 if (error)
                         goto out;
         }
diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c
index 14e682dbe8bf..2232b3c780bd 100644
--- a/fs/gfs2/inode.c
+++ b/fs/gfs2/inode.c
@@ -509,7 +509,7 @@ struct inode *gfs2_lookupi(struct inode *dir, const struct qstr *name,
         }
 
         if (!is_root) {
-                error = gfs2_permission(dir, MAY_EXEC);
+                error = gfs2_permission(dir, MAY_EXEC, 0);
                 if (error)
                         goto out;
         }
@@ -539,7 +539,7 @@ static int create_ok(struct gfs2_inode *dip, const struct qstr *name,
 {
         int error;
 
-        error = gfs2_permission(&dip->i_inode, MAY_WRITE | MAY_EXEC);
+        error = gfs2_permission(&dip->i_inode, MAY_WRITE | MAY_EXEC, 0);
         if (error)
                 return error;
 
diff --git a/fs/gfs2/inode.h b/fs/gfs2/inode.h
index d8499fadcc53..732a183efdb3 100644
--- a/fs/gfs2/inode.h
+++ b/fs/gfs2/inode.h
@@ -113,7 +113,7 @@ extern struct inode *gfs2_lookupi(struct inode *dir, const struct qstr *name,
 extern struct inode *gfs2_createi(struct gfs2_holder *ghs,
                                   const struct qstr *name,
                                   unsigned int mode, dev_t dev);
-extern int gfs2_permission(struct inode *inode, int mask);
+extern int gfs2_permission(struct inode *inode, int mask, unsigned int flags);
 extern int gfs2_setattr_simple(struct gfs2_inode *ip, struct iattr *attr);
 extern struct inode *gfs2_lookup_simple(struct inode *dip, const char *name);
 extern void gfs2_dinode_out(const struct gfs2_inode *ip, void *buf);
diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c
index 3eb1393f7b81..2aeabd4218cc 100644
--- a/fs/gfs2/ops_fstype.c
+++ b/fs/gfs2/ops_fstype.c
@@ -440,7 +440,7 @@ static int gfs2_lookup_root(struct super_block *sb, struct dentry **dptr,
                 iput(inode);
                 return -ENOMEM;
         }
-        dentry->d_op = &gfs2_dops;
+        d_set_d_op(dentry, &gfs2_dops);
         *dptr = dentry;
         return 0;
 }
diff --git a/fs/gfs2/ops_inode.c b/fs/gfs2/ops_inode.c
index 1db6b7343229..1501db4f0e6d 100644
--- a/fs/gfs2/ops_inode.c
+++ b/fs/gfs2/ops_inode.c
@@ -106,7 +106,7 @@ static struct dentry *gfs2_lookup(struct inode *dir, struct dentry *dentry,
 {
         struct inode *inode = NULL;
 
-        dentry->d_op = &gfs2_dops;
+        d_set_d_op(dentry, &gfs2_dops);
 
         inode = gfs2_lookupi(dir, &dentry->d_name, 0);
         if (inode && IS_ERR(inode))
@@ -166,7 +166,7 @@ static int gfs2_link(struct dentry *old_dentry, struct inode *dir,
         if (error)
                 goto out_child;
 
-        error = gfs2_permission(dir, MAY_WRITE | MAY_EXEC);
+        error = gfs2_permission(dir, MAY_WRITE | MAY_EXEC, 0);
         if (error)
                 goto out_gunlock;
 
@@ -289,7 +289,7 @@ static int gfs2_unlink_ok(struct gfs2_inode *dip, const struct qstr *name,
         if (IS_APPEND(&dip->i_inode))
                 return -EPERM;
 
-        error = gfs2_permission(&dip->i_inode, MAY_WRITE | MAY_EXEC);
+        error = gfs2_permission(&dip->i_inode, MAY_WRITE | MAY_EXEC, 0);
         if (error)
                 return error;
 
@@ -822,7 +822,7 @@ static int gfs2_rename(struct inode *odir, struct dentry *odentry,
                         }
                 }
         } else {
-                error = gfs2_permission(ndir, MAY_WRITE | MAY_EXEC);
+                error = gfs2_permission(ndir, MAY_WRITE | MAY_EXEC, 0);
                 if (error)
                         goto out_gunlock;
 
@@ -857,7 +857,7 @@ static int gfs2_rename(struct inode *odir, struct dentry *odentry,
         /* Check out the dir to be renamed */
 
         if (dir_rename) {
-                error = gfs2_permission(odentry->d_inode, MAY_WRITE);
+                error = gfs2_permission(odentry->d_inode, MAY_WRITE, 0);
                 if (error)
                         goto out_gunlock;
         }
@@ -1041,13 +1041,17 @@ static void gfs2_put_link(struct dentry *dentry, struct nameidata *nd, void *p)
  * Returns: errno
  */
 
-int gfs2_permission(struct inode *inode, int mask)
+int gfs2_permission(struct inode *inode, int mask, unsigned int flags)
 {
-        struct gfs2_inode *ip = GFS2_I(inode);
+        struct gfs2_inode *ip;
         struct gfs2_holder i_gh;
         int error;
         int unlock = 0;
 
+        if (flags & IPERM_FLAG_RCU)
+                return -ECHILD;
+
+        ip = GFS2_I(inode);
         if (gfs2_glock_is_locked_by_me(ip->i_gl) == NULL) {
                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
                 if (error)
@@ -1058,7 +1062,7 @@ int gfs2_permission(struct inode *inode, int mask)
         if ((mask & MAY_WRITE) && IS_IMMUTABLE(inode))
                 error = -EACCES;
         else
-                error = generic_permission(inode, mask, gfs2_check_acl);
+                error = generic_permission(inode, mask, flags, gfs2_check_acl);
         if (unlock)
                 gfs2_glock_dq_uninit(&i_gh);
 
diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c
index 2b2c4997430b..16c2ecac7eb7 100644
--- a/fs/gfs2/super.c
+++ b/fs/gfs2/super.c
@@ -1405,11 +1405,18 @@ static struct inode *gfs2_alloc_inode(struct super_block *sb)
         return &ip->i_inode;
 }
 
-static void gfs2_destroy_inode(struct inode *inode)
+static void gfs2_i_callback(struct rcu_head *head)
 {
+        struct inode *inode = container_of(head, struct inode, i_rcu);
+        INIT_LIST_HEAD(&inode->i_dentry);
         kmem_cache_free(gfs2_inode_cachep, inode);
 }
 
+static void gfs2_destroy_inode(struct inode *inode)
+{
+        call_rcu(&inode->i_rcu, gfs2_i_callback);
+}
+
 const struct super_operations gfs2_super_ops = {
         .alloc_inode            = gfs2_alloc_inode,
         .destroy_inode          = gfs2_destroy_inode,