net/mlx4_en: Fix mixed PFC and Global pause user control requests

[pandora-kernel.git] / mm / madvise.c

diff --git a/mm/madvise.c b/mm/madvise.c
index 74bf193..ec8e59c 100644 (file)
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -13,6 +13,7 @@
 #include <linux/hugetlb.h>
 #include <linux/sched.h>
 #include <linux/ksm.h>
+#include <linux/file.h>
 
 /*
  * Any behaviour which results in changes to the vma->vm_flags needs to
@@ -127,6 +128,7 @@ static long madvise_willneed(struct vm_area_struct * vma,
 {
        struct file *file = vma->vm_file;
 
+       *prev = vma;
        if (!file)
                return -EBADF;
 
@@ -135,7 +137,6 @@ static long madvise_willneed(struct vm_area_struct * vma,
                return 0;
        }
 
-       *prev = vma;
        start = ((start - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
        if (end > vma->vm_end)
                end = vma->vm_end;
@@ -197,14 +198,16 @@ static long madvise_remove(struct vm_area_struct *vma,
        struct address_space *mapping;
        loff_t offset, endoff;
        int error;
+       struct file *f;
 
        *prev = NULL;   /* tell sys_madvise we drop mmap_sem */
 
        if (vma->vm_flags & (VM_LOCKED|VM_NONLINEAR|VM_HUGETLB))
                return -EINVAL;
 
-       if (!vma->vm_file || !vma->vm_file->f_mapping
-               || !vma->vm_file->f_mapping->host) {
+       f = vma->vm_file;
+
+       if (!f || !f->f_mapping || !f->f_mapping->host) {
                        return -EINVAL;
        }
 
@@ -218,9 +221,16 @@ static long madvise_remove(struct vm_area_struct *vma,
        endoff = (loff_t)(end - vma->vm_start - 1)
                        + ((loff_t)vma->vm_pgoff << PAGE_SHIFT);
 
-       /* vmtruncate_range needs to take i_mutex */
+       /*
+        * vmtruncate_range may need to take i_mutex.  We need to
+        * explicitly grab a reference because the vma (and hence the
+        * vma's reference to the file) can go away as soon as we drop
+        * mmap_sem.
+        */
+       get_file(f);
        up_read(&current->mm->mmap_sem);
        error = vmtruncate_range(mapping->host, offset, endoff);
+       fput(f);
        down_read(&current->mm->mmap_sem);
        return error;
 }