fs/9p: track open fids

This patch adds accounting of open fids in a list hanging off the i_private
field of the corresponding inode. This allows faster lookups compared to
searching the full 9p client list.

The lookup code is modified accordingly.

Link: http://lkml.kernel.org/r/20200923141146.90046-3-jianyong.wu@arm.com
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: Jianyong Wu <jianyong.wu@arm.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>

diff --git a/fs/9p/fid.c b/fs/9p/fid.c
index 3304984c0fad70e87ee22a70b7c320274c3c7bb7..d11dd430590dc96e227cfba61cb6530782a4978f 100644 (file)
--- a/fs/9p/fid.c
+++ b/fs/9p/fid.c
@@ -39,7 +39,7 @@ void v9fs_fid_add(struct dentry *dentry, struct p9_fid *fid)
 }
 
 /**
- * v9fs_fid_find_inode - search for a fid off of the client list
+ * v9fs_fid_find_inode - search for an open fid off of the inode list
  * @inode: return a fid pointing to a specific inode
  * @uid: return a fid belonging to the specified user
  *
@@ -47,24 +47,38 @@ void v9fs_fid_add(struct dentry *dentry, struct p9_fid *fid)
 
 static struct p9_fid *v9fs_fid_find_inode(struct inode *inode, kuid_t uid)
 {
-       struct p9_client *clnt = v9fs_inode2v9ses(inode)->clnt;
-       struct p9_fid *fid, *fidptr, *ret = NULL;
-       unsigned long flags;
+       struct hlist_head *h;
+       struct p9_fid *fid, *ret = NULL;
 
        p9_debug(P9_DEBUG_VFS, " inode: %p\n", inode);
 
-       spin_lock_irqsave(&clnt->lock, flags);
-       list_for_each_entry_safe(fid, fidptr, &clnt->fidlist, flist) {
-               if (uid_eq(fid->uid, uid) &&
-                  (inode->i_ino == v9fs_qid2ino(&fid->qid))) {
+       spin_lock(&inode->i_lock);
+       h = (struct hlist_head *)&inode->i_private;
+       hlist_for_each_entry(fid, h, ilist) {
+               if (uid_eq(fid->uid, uid)) {
                        ret = fid;
                        break;
                }
        }
-       spin_unlock_irqrestore(&clnt->lock, flags);
+       spin_unlock(&inode->i_lock);
        return ret;
 }
 
+/**
+ * v9fs_open_fid_add - add an open fid to an inode
+ * @dentry: inode that the fid is being added to
+ * @fid: fid to add
+ *
+ */
+
+void v9fs_open_fid_add(struct inode *inode, struct p9_fid *fid)
+{
+       spin_lock(&inode->i_lock);
+       hlist_add_head(&fid->ilist, (struct hlist_head *)&inode->i_private);
+       spin_unlock(&inode->i_lock);
+}
+
+
 /**
  * v9fs_fid_find - retrieve a fid that belongs to the specified uid
  * @dentry: dentry to look for fid in

diff --git a/fs/9p/fid.h b/fs/9p/fid.h
index 928b1093f511c2ce7c1ccdc14c636ea755f95ddf..dfa11df028182c21990accf9e99f347a64c07128 100644 (file)
--- a/fs/9p/fid.h
+++ b/fs/9p/fid.h
@@ -15,6 +15,7 @@ static inline struct p9_fid *v9fs_parent_fid(struct dentry *dentry)
 }
 void v9fs_fid_add(struct dentry *dentry, struct p9_fid *fid);
 struct p9_fid *v9fs_writeback_fid(struct dentry *dentry);
+void v9fs_open_fid_add(struct inode *inode, struct p9_fid *fid);
 static inline struct p9_fid *clone_fid(struct p9_fid *fid)
 {
        return IS_ERR(fid) ? fid :  p9_client_walk(fid, 0, NULL, 1);

diff --git a/fs/9p/vfs_dir.c b/fs/9p/vfs_dir.c
index 674d22bf4f6f75465ad8274c3dde5ba1673cbc3e..d82d8a346f8664e5e7a884a366975b6900149d9d 100644 (file)
--- a/fs/9p/vfs_dir.c
+++ b/fs/9p/vfs_dir.c
@@ -210,6 +210,9 @@ int v9fs_dir_release(struct inode *inode, struct file *filp)
        fid = filp->private_data;
        p9_debug(P9_DEBUG_VFS, "inode: %p filp: %p fid: %d\n",
                 inode, filp, fid ? fid->fid : -1);
+       spin_lock(&inode->i_lock);
+       hlist_del(&fid->ilist);
+       spin_unlock(&inode->i_lock);
        if (fid)
                p9_client_clunk(fid);
        return 0;

diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c
index b177fd3b1eb3bfef4fb0155c5361597bdfb5242c..b0ef225cecd001920e04ce13ffc3fa652c5b454f 100644 (file)
--- a/fs/9p/vfs_file.c
+++ b/fs/9p/vfs_file.c
@@ -96,6 +96,7 @@ int v9fs_file_open(struct inode *inode, struct file *file)
        mutex_unlock(&v9inode->v_mutex);
        if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
                v9fs_cache_inode_set_cookie(inode, file);
+       v9fs_open_fid_add(inode, fid);
        return 0;
 out_error:
        p9_client_clunk(file->private_data);

diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index 31c2fddabb82abcb2b693016a935aa8b49aec7ed..6b243ffcbcf0652d0e0b069a2a4203040186d687 100644 (file)
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -256,6 +256,7 @@ int v9fs_init_inode(struct v9fs_session_info *v9ses,
        inode->i_rdev = rdev;
        inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
        inode->i_mapping->a_ops = &v9fs_addr_operations;
+       inode->i_private = NULL;
 
        switch (mode & S_IFMT) {
        case S_IFIFO:
@@ -796,6 +797,7 @@ v9fs_vfs_atomic_open(struct inode *dir, struct dentry *dentry,
        struct v9fs_session_info *v9ses;
        struct p9_fid *fid, *inode_fid;
        struct dentry *res = NULL;
+       struct inode *inode;
 
        if (d_in_lookup(dentry)) {
                res = v9fs_vfs_lookup(dir, dentry, 0);
@@ -824,7 +826,8 @@ v9fs_vfs_atomic_open(struct inode *dir, struct dentry *dentry,
        }
 
        v9fs_invalidate_inode_attr(dir);
-       v9inode = V9FS_I(d_inode(dentry));
+       inode = d_inode(dentry);
+       v9inode = V9FS_I(inode);
        mutex_lock(&v9inode->v_mutex);
        if ((v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) &&
            !v9inode->writeback_fid &&
@@ -852,6 +855,7 @@ v9fs_vfs_atomic_open(struct inode *dir, struct dentry *dentry,
        file->private_data = fid;
        if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
                v9fs_cache_inode_set_cookie(d_inode(dentry), file);
+       v9fs_open_fid_add(inode, fid);
 
        file->f_mode |= FMODE_CREATED;
 out:

diff --git a/fs/9p/vfs_inode_dotl.c b/fs/9p/vfs_inode_dotl.c
index 0028eccb665a6224aa392dddc9810a093de50368..08f2e089fb0ecea2c94e5c202bf4d31b501dd96d 100644 (file)
--- a/fs/9p/vfs_inode_dotl.c
+++ b/fs/9p/vfs_inode_dotl.c
@@ -342,6 +342,7 @@ v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
        file->private_data = ofid;
        if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
                v9fs_cache_inode_set_cookie(inode, file);
+       v9fs_open_fid_add(inode, ofid);
        file->f_mode |= FMODE_CREATED;
 out:
        v9fs_put_acl(dacl, pacl);

diff --git a/include/net/9p/client.h b/include/net/9p/client.h
index dd5b5bd781a4957f00203c7499241f45065e7510..ce7882da8e860909fa8882884f65f2010b8b585e 100644 (file)
--- a/include/net/9p/client.h
+++ b/include/net/9p/client.h
@@ -152,6 +152,7 @@ struct p9_fid {
        void *rdir;
 
        struct hlist_node dlist;        /* list of all fids attached to a dentry */
+       struct hlist_node ilist;
 };
 
 /**