@@ -73,7 +73,7 @@ extern void flush_cache_all(void);
extern void flush_cache_range(struct vm_area_struct *vma, unsigned long start, unsigned long end);
extern void flush_icache_range(unsigned long start, unsigned long end);
extern void __flush_dcache_area(void *addr, size_t len);
-extern void __flush_cache_user_range(unsigned long start, unsigned long end);
+extern long __flush_cache_user_range(unsigned long start, unsigned long end);
static inline void flush_cache_mm(struct mm_struct *mm)
{
@@ -39,6 +39,15 @@ struct exec_domain;
typedef unsigned long mm_segment_t;
+struct compat_restart_block {
+ union {
+ /* For user cache flushing */
+ struct {
+ unsigned long start;
+ unsigned long end;
+ } cache;
+ };
+};
/*
* low level task data that entry.S needs immediate access to.
* __switch_to() assumes cpu_context follows immediately after cpu_domain.
@@ -51,6 +60,9 @@ struct thread_info {
struct restart_block restart_block;
int preempt_count; /* 0 => preemptable, <0 => bug */
int cpu; /* cpu */
+#ifdef CONFIG_COMPAT
+ struct compat_restart_block compat_restart_block;
+#endif
};
#define INIT_THREAD_INFO(tsk) \
@@ -28,29 +28,65 @@
#include <asm/cacheflush.h>
#include <asm/unistd.h>
-static inline void
-do_compat_cache_op(unsigned long start, unsigned long end, int flags)
+static long do_compat_cache_op_restart(struct restart_block *);
+
+static long
+__do_compat_cache_op(unsigned long start, unsigned long end)
{
- struct mm_struct *mm = current->active_mm;
- struct vm_area_struct *vma;
+ long ret;
- if (end < start || flags)
- return;
-
- down_read(&mm->mmap_sem);
- vma = find_vma(mm, start);
- if (vma && vma->vm_start < end) {
- if (start < vma->vm_start)
- start = vma->vm_start;
- if (end > vma->vm_end)
- end = vma->vm_end;
- up_read(&mm->mmap_sem);
- __flush_cache_user_range(start & PAGE_MASK, PAGE_ALIGN(end));
- return;
- }
- up_read(&mm->mmap_sem);
+ do {
+ unsigned long chunk = min(PAGE_SIZE, end - start);
+
+ if (signal_pending(current)) {
+ struct thread_info *ti = current_thread_info();
+
+ ti->restart_block = (struct restart_block) {
+ .fn = do_compat_cache_op_restart,
+ };
+
+ ti->compat_restart_block = (struct compat_restart_block) {
+ {
+ .cache = {
+ .start = start,
+ .end = end,
+ },
+ },
+ };
+
+ return -ERESTART_RESTARTBLOCK;
+ }
+ ret = __flush_cache_user_range(start, start + chunk);
+ if (ret)
+ return ret;
+
+ cond_resched();
+ start += chunk;
+ } while (start < end);
+
+ return 0;
}
+static long do_compat_cache_op_restart(struct restart_block *unused)
+{
+ struct compat_restart_block *restart_block;
+
+ restart_block = ¤t_thread_info()->compat_restart_block;
+ return __do_compat_cache_op(restart_block->cache.start,
+ restart_block->cache.end);
+}
+
+static inline long
+do_compat_cache_op(unsigned long start, unsigned long end, int flags)
+{
+ if (end < start || flags)
+ return -EINVAL;
+
+ if (!access_ok(VERIFY_READ, start, end - start))
+ return -EFAULT;
+
+ return __do_compat_cache_op(start, end);
+}
/*
* Handle all unrecognised system calls.
*/
@@ -74,8 +110,7 @@ long compat_arm_syscall(struct pt_regs *regs)
* the specified region).
*/
case __ARM_NR_compat_cacheflush:
- do_compat_cache_op(regs->regs[0], regs->regs[1], regs->regs[2]);
- return 0;
+ return do_compat_cache_op(regs->regs[0], regs->regs[1], regs->regs[2]);
case __ARM_NR_compat_set_tls:
current->thread.tp_value = regs->regs[0];
@@ -17,6 +17,7 @@
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
+#include <linux/errno.h>
#include <linux/linkage.h>
#include <linux/init.h>
#include <asm/assembler.h>
@@ -138,9 +139,12 @@ USER(9f, ic ivau, x4 ) // invalidate I line PoU
add x4, x4, x2
cmp x4, x1
b.lo 1b
-9: // ignore any faulting cache operation
dsb ish
isb
+ mov x0, #0
+ ret
+9:
+ mov x0, #-EFAULT
ret
ENDPROC(flush_icache_range)
ENDPROC(__flush_cache_user_range)