dlm: always use GFP_NOFS

Replace all GFP_KERNEL and ls_allocation with GFP_NOFS.
ls_allocation would be GFP_KERNEL for userland lockspaces
and GFP_NOFS for file system lockspaces.

It was discovered that any lockspaces on the system can
affect all others by triggering memory reclaim in the
file system which could in turn call back into the dlm
to acquire locks, deadlocking dlm threads that were
shared by all lockspaces, like dlm_recv.

Signed-off-by: David Teigland <teigland@redhat.com>

1 files changed, 6 insertions, 6 deletions

diff --git a/fs/dlm/user.c b/fs/dlm/user.c
index ebce994ab0b7..e73a4bb572aa 100644
--- a/fs/dlm/user.c
+++ b/fs/dlm/user.c
@@ -267,7 +267,7 @@ static int device_user_lock(struct dlm_user_proc *proc,
                 goto out;
         }
 
-        ua = kzalloc(sizeof(struct dlm_user_args), GFP_KERNEL);
+        ua = kzalloc(sizeof(struct dlm_user_args), GFP_NOFS);
         if (!ua)
                 goto out;
         ua->proc = proc;
@@ -307,7 +307,7 @@ static int device_user_unlock(struct dlm_user_proc *proc,
         if (!ls)
                 return -ENOENT;
 
-        ua = kzalloc(sizeof(struct dlm_user_args), GFP_KERNEL);
+        ua = kzalloc(sizeof(struct dlm_user_args), GFP_NOFS);
         if (!ua)
                 goto out;
         ua->proc = proc;
@@ -352,7 +352,7 @@ static int dlm_device_register(struct dlm_ls *ls, char *name)
 
         error = -ENOMEM;
         len = strlen(name) + strlen(name_prefix) + 2;
-        ls->ls_device.name = kzalloc(len, GFP_KERNEL);
+        ls->ls_device.name = kzalloc(len, GFP_NOFS);
         if (!ls->ls_device.name)
                 goto fail;
 
@@ -520,7 +520,7 @@ static ssize_t device_write(struct file *file, const char __user *buf,
 #endif
                 return -EINVAL;
 
-        kbuf = kzalloc(count + 1, GFP_KERNEL);
+        kbuf = kzalloc(count + 1, GFP_NOFS);
         if (!kbuf)
                 return -ENOMEM;
 
@@ -546,7 +546,7 @@ static ssize_t device_write(struct file *file, const char __user *buf,
 
                 /* add 1 after namelen so that the name string is terminated */
                 kbuf = kzalloc(sizeof(struct dlm_write_request) + namelen + 1,
-                               GFP_KERNEL);
+                               GFP_NOFS);
                 if (!kbuf) {
                         kfree(k32buf);
                         return -ENOMEM;
@@ -648,7 +648,7 @@ static int device_open(struct inode *inode, struct file *file)
         if (!ls)
                 return -ENOENT;
 
-        proc = kzalloc(sizeof(struct dlm_user_proc), GFP_KERNEL);
+        proc = kzalloc(sizeof(struct dlm_user_proc), GFP_NOFS);
         if (!proc) {
                 dlm_put_lockspace(ls);
                 return -ENOMEM;