Btrfs: avoid waiting for delayed refs when we must not

[karo-tx-linux.git] / fs / xattr.c

diff --git a/fs/xattr.c b/fs/xattr.c
index d6dfd247bb2f4425fdfbd9c57b892a07c3922847..3c8c1cc333c7c79dfa105049a62d8b6e1c28661c 100644 (file)
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -19,8 +19,9 @@
 #include <linux/export.h>
 #include <linux/fsnotify.h>
 #include <linux/audit.h>
-#include <asm/uaccess.h>
+#include <linux/vmalloc.h>
 
+#include <asm/uaccess.h>
 
 /*
  * Check permissions for extended attribute access.  This is a bit complicated
@@ -320,6 +321,7 @@ setxattr(struct dentry *d, const char __user *name, const void __user *value,
 {
        int error;
        void *kvalue = NULL;
+       void *vvalue = NULL;    /* If non-NULL, we used vmalloc() */
        char kname[XATTR_NAME_MAX + 1];
 
        if (flags & ~(XATTR_CREATE|XATTR_REPLACE))
@@ -334,13 +336,25 @@ setxattr(struct dentry *d, const char __user *name, const void __user *value,
        if (size) {
                if (size > XATTR_SIZE_MAX)
                        return -E2BIG;
-               kvalue = memdup_user(value, size);
-               if (IS_ERR(kvalue))
-                       return PTR_ERR(kvalue);
+               kvalue = kmalloc(size, GFP_KERNEL | __GFP_NOWARN);
+               if (!kvalue) {
+                       vvalue = vmalloc(size);
+                       if (!vvalue)
+                               return -ENOMEM;
+                       kvalue = vvalue;
+               }
+               if (copy_from_user(kvalue, value, size)) {
+                       error = -EFAULT;
+                       goto out;
+               }
        }
 
        error = vfs_setxattr(d, kname, kvalue, size, flags);
-       kfree(kvalue);
+out:
+       if (vvalue)
+               vfree(vvalue);
+       else
+               kfree(kvalue);
        return error;
 }
 
@@ -492,13 +506,18 @@ listxattr(struct dentry *d, char __user *list, size_t size)
 {
        ssize_t error;
        char *klist = NULL;
+       char *vlist = NULL;     /* If non-NULL, we used vmalloc() */
 
        if (size) {
                if (size > XATTR_LIST_MAX)
                        size = XATTR_LIST_MAX;
-               klist = kmalloc(size, GFP_KERNEL);
-               if (!klist)
-                       return -ENOMEM;
+               klist = kmalloc(size, __GFP_NOWARN | GFP_KERNEL);
+               if (!klist) {
+                       vlist = vmalloc(size);
+                       if (!vlist)
+                               return -ENOMEM;
+                       klist = vlist;
+               }
        }
 
        error = vfs_listxattr(d, klist, size);
@@ -510,7 +529,10 @@ listxattr(struct dentry *d, char __user *list, size_t size)
                   than XATTR_LIST_MAX bytes. Not possible. */
                error = -E2BIG;
        }
-       kfree(klist);
+       if (vlist)
+               vfree(vlist);
+       else
+               kfree(klist);
        return error;
 }