fs: icache RCU free inodes

[mirror_ubuntu-zesty-kernel.git] / fs / jfs / namei.c

diff --git a/fs/jfs/namei.c b/fs/jfs/namei.c
index a9cf8e8675be8713dc5f9311faa20fefcac85156..57f90dad8919db3a8440ce152eb27a53f0c7c5c7 100644 (file)
--- a/fs/jfs/namei.c
+++ b/fs/jfs/namei.c
@@ -18,6 +18,7 @@
  */
 
 #include <linux/fs.h>
+#include <linux/namei.h>
 #include <linux/ctype.h>
 #include <linux/quotaops.h>
 #include <linux/exportfs.h>
@@ -839,7 +840,7 @@ static int jfs_link(struct dentry *old_dentry,
        ip->i_ctime = CURRENT_TIME;
        dir->i_ctime = dir->i_mtime = CURRENT_TIME;
        mark_inode_dirty(dir);
-       atomic_inc(&ip->i_count);
+       ihold(ip);
 
        iplist[0] = ip;
        iplist[1] = dir;
@@ -1573,7 +1574,8 @@ const struct file_operations jfs_dir_operations = {
        .llseek         = generic_file_llseek,
 };
 
-static int jfs_ci_hash(struct dentry *dir, struct qstr *this)
+static int jfs_ci_hash(const struct dentry *dir, const struct inode *inode,
+               struct qstr *this)
 {
        unsigned long hash;
        int i;
@@ -1586,32 +1588,61 @@ static int jfs_ci_hash(struct dentry *dir, struct qstr *this)
        return 0;
 }
 
-static int jfs_ci_compare(struct dentry *dir, struct qstr *a, struct qstr *b)
+static int jfs_ci_compare(const struct dentry *parent,
+               const struct inode *pinode,
+               const struct dentry *dentry, const struct inode *inode,
+               unsigned int len, const char *str, const struct qstr *name)
 {
        int i, result = 1;
 
-       if (a->len != b->len)
+       if (len != name->len)
                goto out;
-       for (i=0; i < a->len; i++) {
-               if (tolower(a->name[i]) != tolower(b->name[i]))
+       for (i=0; i < len; i++) {
+               if (tolower(str[i]) != tolower(name->name[i]))
                        goto out;
        }
        result = 0;
+out:
+       return result;
+}
 
+static int jfs_ci_revalidate(struct dentry *dentry, struct nameidata *nd)
+{
        /*
-        * We want creates to preserve case.  A negative dentry, a, that
-        * has a different case than b may cause a new entry to be created
-        * with the wrong case.  Since we can't tell if a comes from a negative
-        * dentry, we blindly replace it with b.  This should be harmless if
-        * a is not a negative dentry.
+        * This is not negative dentry. Always valid.
+        *
+        * Note, rename() to existing directory entry will have ->d_inode,
+        * and will use existing name which isn't specified name by user.
+        *
+        * We may be able to drop this positive dentry here. But dropping
+        * positive dentry isn't good idea. So it's unsupported like
+        * rename("filename", "FILENAME") for now.
         */
-       memcpy((unsigned char *)a->name, b->name, a->len);
-out:
-       return result;
+       if (dentry->d_inode)
+               return 1;
+
+       /*
+        * This may be nfsd (or something), anyway, we can't see the
+        * intent of this. So, since this can be for creation, drop it.
+        */
+       if (!nd)
+               return 0;
+
+       /*
+        * Drop the negative dentry, in order to make sure to use the
+        * case sensitive name which is specified by user if this is
+        * for creation.
+        */
+       if (!(nd->flags & (LOOKUP_CONTINUE | LOOKUP_PARENT))) {
+               if (nd->flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))
+                       return 0;
+       }
+       return 1;
 }
 
 const struct dentry_operations jfs_ci_dentry_operations =
 {
        .d_hash = jfs_ci_hash,
        .d_compare = jfs_ci_compare,
+       .d_revalidate = jfs_ci_revalidate,
 };