NFS: Reduce the stack footprint of nfs_proc_create

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 66 insertions, 52 deletions

diff --git a/fs/nfs/proc.c b/fs/nfs/proc.c
index 0288be80444f..aa61f2c66068 100644
--- a/fs/nfs/proc.c
+++ b/fs/nfs/proc.c
@@ -224,35 +224,60 @@ static int nfs_proc_readlink(struct inode *inode, struct page *page,
         return status;
 }
 
+struct nfs_createdata {
+        struct nfs_createargs arg;
+        struct nfs_diropok res;
+        struct nfs_fh fhandle;
+        struct nfs_fattr fattr;
+};
+
+static struct nfs_createdata *nfs_alloc_createdata(struct inode *dir,
+                struct dentry *dentry, struct iattr *sattr)
+{
+        struct nfs_createdata *data;
+
+        data = kmalloc(sizeof(*data), GFP_KERNEL);
+
+        if (data != NULL) {
+                data->arg.fh = NFS_FH(dir);
+                data->arg.name = dentry->d_name.name;
+                data->arg.len = dentry->d_name.len;
+                data->arg.sattr = sattr;
+                nfs_fattr_init(&data->fattr);
+                data->fhandle.size = 0;
+                data->res.fh = &data->fhandle;
+                data->res.fattr = &data->fattr;
+        }
+        return data;
+};
+
+static void nfs_free_createdata(const struct nfs_createdata *data)
+{
+        kfree(data);
+}
+
 static int
 nfs_proc_create(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
                 int flags, struct nameidata *nd)
 {
-        struct nfs_fh           fhandle;
-        struct nfs_fattr        fattr;
-        struct nfs_createargs   arg = {
-                .fh             = NFS_FH(dir),
-                .name           = dentry->d_name.name,
-                .len            = dentry->d_name.len,
-                .sattr          = sattr
-        };
-        struct nfs_diropok      res = {
-                .fh             = &fhandle,
-                .fattr          = &fattr
-        };
+        struct nfs_createdata *data;
         struct rpc_message msg = {
                 .rpc_proc       = &nfs_procedures[NFSPROC_CREATE],
-                .rpc_argp       = &arg,
-                .rpc_resp       = &res,
         };
-        int                     status;
+        int status = -ENOMEM;
 
-        nfs_fattr_init(&fattr);
         dprintk("NFS call  create %s\n", dentry->d_name.name);
+        data = nfs_alloc_createdata(dir, dentry, sattr);
+        if (data == NULL)
+                goto out;
+        msg.rpc_argp = &data->arg;
+        msg.rpc_resp = &data->res;
         status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
         nfs_mark_for_revalidate(dir);
         if (status == 0)
-                status = nfs_instantiate(dentry, &fhandle, &fattr);
+                status = nfs_instantiate(dentry, data->res.fh, data->res.fattr);
+        nfs_free_createdata(data);
+out:
         dprintk("NFS reply create: %d\n", status);
         return status;
 }
@@ -264,24 +289,12 @@ static int
 nfs_proc_mknod(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
                dev_t rdev)
 {
-        struct nfs_fh fhandle;
-        struct nfs_fattr fattr;
-        struct nfs_createargs   arg = {
-                .fh             = NFS_FH(dir),
-                .name           = dentry->d_name.name,
-                .len            = dentry->d_name.len,
-                .sattr          = sattr
-        };
-        struct nfs_diropok      res = {
-                .fh             = &fhandle,
-                .fattr          = &fattr
-        };
+        struct nfs_createdata *data;
         struct rpc_message msg = {
                 .rpc_proc       = &nfs_procedures[NFSPROC_CREATE],
-                .rpc_argp       = &arg,
-                .rpc_resp       = &res,
         };
-        int status, mode;
+        umode_t mode;
+        int status = -ENOMEM;
 
         dprintk("NFS call  mknod %s\n", dentry->d_name.name);
 
@@ -294,17 +307,24 @@ nfs_proc_mknod(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
                 sattr->ia_size = new_encode_dev(rdev);/* get out your barf bag */
         }
 
-        nfs_fattr_init(&fattr);
+        data = nfs_alloc_createdata(dir, dentry, sattr);
+        if (data == NULL)
+                goto out;
+        msg.rpc_argp = &data->arg;
+        msg.rpc_resp = &data->res;
+
         status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
         nfs_mark_for_revalidate(dir);
 
         if (status == -EINVAL && S_ISFIFO(mode)) {
                 sattr->ia_mode = mode;
-                nfs_fattr_init(&fattr);
+                nfs_fattr_init(data->res.fattr);
                 status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
         }
         if (status == 0)
-                status = nfs_instantiate(dentry, &fhandle, &fattr);
+                status = nfs_instantiate(dentry, data->res.fh, data->res.fattr);
+        nfs_free_createdata(data);
+out:
         dprintk("NFS reply mknod: %d\n", status);
         return status;
 }
@@ -440,31 +460,25 @@ nfs_proc_symlink(struct inode *dir, struct dentry *dentry, struct page *page,
 static int
 nfs_proc_mkdir(struct inode *dir, struct dentry *dentry, struct iattr *sattr)
 {
-        struct nfs_fh fhandle;
-        struct nfs_fattr fattr;
-        struct nfs_createargs   arg = {
-                .fh             = NFS_FH(dir),
-                .name           = dentry->d_name.name,
-                .len            = dentry->d_name.len,
-                .sattr          = sattr
-        };
-        struct nfs_diropok      res = {
-                .fh             = &fhandle,
-                .fattr          = &fattr
-        };
+        struct nfs_createdata *data;
         struct rpc_message msg = {
                 .rpc_proc       = &nfs_procedures[NFSPROC_MKDIR],
-                .rpc_argp       = &arg,
-                .rpc_resp       = &res,
         };
-        int                     status;
+        int status = -ENOMEM;
 
         dprintk("NFS call  mkdir %s\n", dentry->d_name.name);
-        nfs_fattr_init(&fattr);
+        data = nfs_alloc_createdata(dir, dentry, sattr);
+        if (data == NULL)
+                goto out;
+        msg.rpc_argp = &data->arg;
+        msg.rpc_resp = &data->res;
+
         status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
         nfs_mark_for_revalidate(dir);
         if (status == 0)
-                status = nfs_instantiate(dentry, &fhandle, &fattr);
+                status = nfs_instantiate(dentry, data->res.fh, data->res.fattr);
+        nfs_free_createdata(data);
+out:
         dprintk("NFS reply mkdir: %d\n", status);
         return status;
 }