[PATCH 2/8] mm: remove unused GUP flags

Hugh Dickins
2009-09-07T21:31:55Z

GUP_FLAGS_IGNORE_VMA_PERMISSIONS and GUP_FLAGS_IGNORE_SIGKILL were
flags added solely to prevent __get_user_pages() from doing some of
what it usually does, in the munlock case: we can now remove them.

Signed-off-by: Hugh Dickins <hugh.dickins@tiscali.co.uk>
---

mm/internal.h | 6 ++----
mm/memory.c | 14 ++++----------
mm/nommu.c | 6 ++----
3 files changed, 8 insertions(+), 18 deletions(-)

--- mm1/mm/internal.h 2009-06-25 05:18:10.000000000 +0100
+++ mm2/mm/internal.h 2009-09-07 13:16:22.000000000 +0100
@@ -250,10 +250,8 @@ static inline void mminit_validate_memmo
}
#endif /* CONFIG_SPARSEMEM */

-#define GUP_FLAGS_WRITE 0x1
-#define GUP_FLAGS_FORCE 0x2
-#define GUP_FLAGS_IGNORE_VMA_PERMISSIONS 0x4
-#define GUP_FLAGS_IGNORE_SIGKILL 0x8
+#define GUP_FLAGS_WRITE 0x01
+#define GUP_FLAGS_FORCE 0x02

int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
unsigned long start, int len, int flags,
--- mm1/mm/memory.c 2009-09-05 14:40:16.000000000 +0100
+++ mm2/mm/memory.c 2009-09-07 13:16:22.000000000 +0100
@@ -1217,8 +1217,6 @@ int __get_user_pages(struct task_struct
unsigned int vm_flags = 0;
int write = !!(flags & GUP_FLAGS_WRITE);
int force = !!(flags & GUP_FLAGS_FORCE);
- int ignore = !!(flags & GUP_FLAGS_IGNORE_VMA_PERMISSIONS);
- int ignore_sigkill = !!(flags & GUP_FLAGS_IGNORE_SIGKILL);

if (nr_pages <= 0)
return 0;
@@ -1244,7 +1242,7 @@ int __get_user_pages(struct task_struct
pte_t *pte;

/* user gate pages are read-only */
- if (!ignore && write)
+ if (write)
return i ? : -EFAULT;
if (pg > TASK_SIZE)
pgd = pgd_offset_k(pg);
@@ -1278,7 +1276,7 @@ int __get_user_pages(struct task_struct

if (!vma ||
(vma->vm_flags & (VM_IO | VM_PFNMAP)) ||
- (!ignore && !(vm_flags & vma->vm_flags)))
+ !(vm_flags & vma->vm_flags))
return i ? : -EFAULT;

if (is_vm_hugetlb_page(vma)) {
@@ -1298,13 +1296,9 @@ int __get_user_pages(struct task_struct

/*
* If we have a pending SIGKILL, don't keep faulting
- * pages and potentially allocating memory, unless
- * current is handling munlock--e.g., on exit. In
- * that case, we are not allocating memory. Rather,
- * we're only unlocking already resident/mapped pages.
+ * pages and potentially allocating memory.
*/
- if (unlikely(!ignore_sigkill &&
- fatal_signal_pending(current)))
+ if (unlikely(fatal_signal_pending(current)))
return i ? i : -ERESTARTSYS;

if (write)
--- mm1/mm/nommu.c 2009-09-05 14:40:16.000000000 +0100
+++ mm2/mm/nommu.c 2009-09-07 13:16:22.000000000 +0100
@@ -136,7 +136,6 @@ int __get_user_pages(struct task_struct
int i;
int write = !!(flags & GUP_FLAGS_WRITE);
int force = !!(flags & GUP_FLAGS_FORCE);
- int ignore = !!(flags & GUP_FLAGS_IGNORE_VMA_PERMISSIONS);

/* calculate required read or write permissions.
* - if 'force' is set, we only require the "MAY" flags.
@@ -150,8 +149,8 @@ int __get_user_pages(struct task_struct
goto finish_or_fault;

/* protect what we can, including chardevs */
- if (vma->vm_flags & (VM_IO | VM_PFNMAP) ||
- (!ignore && !(vm_flags & vma->vm_flags)))
+ if ((vma->vm_flags & (VM_IO | VM_PFNMAP)) ||
+ !(vm_flags & vma->vm_flags))
goto finish_or_fault;

if (pages) {
@@ -170,7 +169,6 @@ finish_or_fault:
return i ? : -EFAULT;
}

-
/*
* get a list of pages in an address range belonging to the specified process
* and indicate the VMA that covers each page