fs/9p: Add fid to inode in cached mode
The fid attached to inode will be opened O_RDWR mode and is used
for dirty page writeback only.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
diff --git a/fs/9p/fid.c b/fs/9p/fid.c
index b00223c..9d6a5d3 100644
--- a/fs/9p/fid.c
+++ b/fs/9p/fid.c
@@ -261,3 +261,29 @@
ret = p9_client_walk(fid, 0, NULL, 1);
return ret;
}
+
+
+struct p9_fid *v9fs_writeback_fid(struct dentry *dentry)
+{
+ int err;
+ struct p9_fid *fid;
+
+ fid = v9fs_fid_clone(dentry);
+ if (IS_ERR(fid))
+ goto error_out;
+ /*
+ * writeback fid will only be used to write back the
+ * dirty pages. We always request for the open fid in read-write
+ * mode so that a partial page write which result in page
+ * read can work.
+ * FIXME!!: we should make the fid owned by uid = 0
+ */
+ err = p9_client_open(fid, O_RDWR);
+ if (err < 0) {
+ p9_client_clunk(fid);
+ fid = ERR_PTR(err);
+ goto error_out;
+ }
+error_out:
+ return fid;
+}
diff --git a/fs/9p/fid.h b/fs/9p/fid.h
index c3bbd6a..c058f1c 100644
--- a/fs/9p/fid.h
+++ b/fs/9p/fid.h
@@ -45,3 +45,4 @@
struct p9_fid *v9fs_fid_lookup(struct dentry *dentry);
struct p9_fid *v9fs_fid_clone(struct dentry *dentry);
int v9fs_fid_add(struct dentry *dentry, struct p9_fid *fid);
+struct p9_fid *v9fs_writeback_fid(struct dentry *dentry);
diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c
index 6e1e8f43..e966f15 100644
--- a/fs/9p/vfs_file.c
+++ b/fs/9p/vfs_file.c
@@ -86,11 +86,30 @@
}
file->private_data = fid;
+ if (v9ses->cache && !inode->i_private) {
+ /*
+ * clone a fid and add it to inode->i_private
+ * we do it during open time instead of
+ * page dirty time via write_begin/page_mkwrite
+ * because we want write after unlink usecase
+ * to work.
+ */
+ fid = v9fs_writeback_fid(file->f_path.dentry);
+ if (IS_ERR(fid)) {
+ err = PTR_ERR(fid);
+ goto out_error;
+ }
+ inode->i_private = (void *) fid;
+ }
#ifdef CONFIG_9P_FSCACHE
if (v9ses->cache)
v9fs_cache_inode_set_cookie(inode, file);
#endif
return 0;
+out_error:
+ p9_client_clunk(file->private_data);
+ file->private_data = NULL;
+ return err;
}
/**
diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index 95f5501..a0d65a3 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -417,6 +417,11 @@
#ifdef CONFIG_9P_FSCACHE
v9fs_cache_inode_put_cookie(inode);
#endif
+ /* clunk the fid stashed in inode->i_private */
+ if (inode->i_private) {
+ p9_client_clunk((struct p9_fid *)inode->i_private);
+ inode->i_private = NULL;
+ }
}
struct inode *
@@ -578,7 +583,7 @@
u32 perm;
int flags;
struct v9fs_session_info *v9ses;
- struct p9_fid *fid;
+ struct p9_fid *fid, *inode_fid;
struct file *filp;
err = 0;
@@ -601,6 +606,21 @@
/* if we are opening a file, assign the open fid to the file */
if (nd && nd->flags & LOOKUP_OPEN) {
+ if (v9ses->cache && !dentry->d_inode->i_private) {
+ /*
+ * clone a fid and add it to inode->i_private
+ * we do it during open time instead of
+ * page dirty time via write_begin/page_mkwrite
+ * because we want write after unlink usecase
+ * to work.
+ */
+ inode_fid = v9fs_writeback_fid(dentry);
+ if (IS_ERR(inode_fid)) {
+ err = PTR_ERR(inode_fid);
+ goto error;
+ }
+ dentry->d_inode->i_private = (void *) inode_fid;
+ }
filp = lookup_instantiate_filp(nd, dentry, generic_file_open);
if (IS_ERR(filp)) {
err = PTR_ERR(filp);
diff --git a/fs/9p/vfs_inode_dotl.c b/fs/9p/vfs_inode_dotl.c
index 265f583..1327464 100644
--- a/fs/9p/vfs_inode_dotl.c
+++ b/fs/9p/vfs_inode_dotl.c
@@ -142,7 +142,7 @@
mode_t mode;
struct v9fs_session_info *v9ses;
struct p9_fid *fid = NULL;
- struct p9_fid *dfid, *ofid;
+ struct p9_fid *dfid, *ofid, *inode_fid;
struct file *filp;
struct p9_qid qid;
struct inode *inode;
@@ -218,7 +218,21 @@
/* Now set the ACL based on the default value */
v9fs_set_create_acl(dentry, dacl, pacl);
-
+ if (v9ses->cache && !inode->i_private) {
+ /*
+ * clone a fid and add it to inode->i_private
+ * we do it during open time instead of
+ * page dirty time via write_begin/page_mkwrite
+ * because we want write after unlink usecase
+ * to work.
+ */
+ inode_fid = v9fs_writeback_fid(dentry);
+ if (IS_ERR(inode_fid)) {
+ err = PTR_ERR(inode_fid);
+ goto error;
+ }
+ inode->i_private = (void *) inode_fid;
+ }
/* Since we are opening a file, assign the open fid to the file */
filp = lookup_instantiate_filp(nd, dentry, generic_file_open);
if (IS_ERR(filp)) {