gru: generic infrastructure for context options

Change the user GRU request for specifying the "task_slice" option to use
a generic infrastructure that can be expanded in the future to include
additional context options.  No new capabilities are added with this
patch.

Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

5 files changed, 35 insertions, 13 deletions

diff --git a/drivers/misc/sgi-gru/grufault.c b/drivers/misc/sgi-gru/grufault.c
index cdd151b30dc7..b894b7ed9c35 100644
--- a/drivers/misc/sgi-gru/grufault.c
+++ b/drivers/misc/sgi-gru/grufault.c
@@ -749,18 +749,30 @@ long gru_get_gseg_statistics(unsigned long arg)
  * Register the current task as the user of the GSEG slice.
  * Needed for TLB fault interrupt targeting.
  */
-int gru_set_task_slice(long address)
+int gru_set_context_option(unsigned long arg)
 {
         struct gru_thread_state *gts;
+        struct gru_set_context_option_req req;
+        int ret = 0;
 
-        STAT(set_task_slice);
-        gru_dbg(grudev, "address 0x%lx\n", address);
-        gts = gru_alloc_locked_gts(address);
+        STAT(set_context_option);
+        if (copy_from_user(&req, (void __user *)arg, sizeof(req)))
+                return -EFAULT;
+        gru_dbg(grudev, "op %d, gseg 0x%lx, value1 0x%lx\n", req.op, req.gseg, req.val1);
+
+        gts = gru_alloc_locked_gts(req.gseg);
         if (!gts)
                 return -EINVAL;
 
-        gts->ts_tgid_owner = current->tgid;
+        switch (req.op) {
+        case sco_gseg_owner:
+                /* Register the current task as the GSEG owner */
+                gts->ts_tgid_owner = current->tgid;
+                break;
+        default:
+                ret = -EINVAL;
+        }
         gru_unlock_gts(gts);
 
-        return 0;
+        return ret;
 }
diff --git a/drivers/misc/sgi-gru/grufile.c b/drivers/misc/sgi-gru/grufile.c
index 2b72629db91a..fa2d93a9fb8d 100644
--- a/drivers/misc/sgi-gru/grufile.c
+++ b/drivers/misc/sgi-gru/grufile.c
@@ -198,8 +198,8 @@ static long gru_file_unlocked_ioctl(struct file *file, unsigned int req,
         case GRU_CREATE_CONTEXT:
                 err = gru_create_new_context(arg);
                 break;
-        case GRU_SET_TASK_SLICE:
-                err = gru_set_task_slice(arg);
+        case GRU_SET_CONTEXT_OPTION:
+                err = gru_set_context_option(arg);
                 break;
         case GRU_USER_GET_EXCEPTION_DETAIL:
                 err = gru_get_exception_detail(arg);
diff --git a/drivers/misc/sgi-gru/grulib.h b/drivers/misc/sgi-gru/grulib.h
index 8ed6acbc47c7..8615b904a7c7 100644
--- a/drivers/misc/sgi-gru/grulib.h
+++ b/drivers/misc/sgi-gru/grulib.h
@@ -32,8 +32,8 @@
 /* Set Number of Request Blocks */
 #define GRU_CREATE_CONTEXT              _IOWR(GRU_IOCTL_NUM, 1, void *)
 
-/* Register task as using the slice */
-#define GRU_SET_TASK_SLICE              _IOWR(GRU_IOCTL_NUM, 5, void *)
+/*  Set Context Options */
+#define GRU_SET_CONTEXT_OPTION          _IOWR(GRU_IOCTL_NUM, 4, void *)
 
 /* Fetch exception detail */
 #define GRU_USER_GET_EXCEPTION_DETAIL   _IOWR(GRU_IOCTL_NUM, 6, void *)
@@ -96,6 +96,16 @@ struct gru_unload_context_req {
 };
 
 /*
+ * Structure used to set context options
+ */
+enum {sco_gseg_owner};
+struct gru_set_context_option_req {
+        unsigned long   gseg;
+        int             op;
+        unsigned long   val1;
+};
+
+/*
  * Structure used to pass TLB flush parameters to the driver
  */
 struct gru_flush_tlb_req {
diff --git a/drivers/misc/sgi-gru/gruprocfs.c b/drivers/misc/sgi-gru/gruprocfs.c
index b5b9cf5c182e..9cbf95bedce6 100644
--- a/drivers/misc/sgi-gru/gruprocfs.c
+++ b/drivers/misc/sgi-gru/gruprocfs.c
@@ -73,7 +73,7 @@ static int statistics_show(struct seq_file *s, void *p)
         printstat(s, user_flush_tlb);
         printstat(s, user_unload_context);
         printstat(s, user_exception);
-        printstat(s, set_task_slice);
+        printstat(s, set_context_option);
         printstat(s, migrate_check);
         printstat(s, migrated_retarget);
         printstat(s, migrated_unload);
diff --git a/drivers/misc/sgi-gru/grutables.h b/drivers/misc/sgi-gru/grutables.h
index 63b76e2732ff..ee2f4121db21 100644
--- a/drivers/misc/sgi-gru/grutables.h
+++ b/drivers/misc/sgi-gru/grutables.h
@@ -198,7 +198,7 @@ struct gru_stats_s {
         atomic_long_t user_flush_tlb;
         atomic_long_t user_unload_context;
         atomic_long_t user_exception;
-        atomic_long_t set_task_slice;
+        atomic_long_t set_context_option;
         atomic_long_t migrate_check;
         atomic_long_t migrated_retarget;
         atomic_long_t migrated_unload;
@@ -649,7 +649,7 @@ extern int gru_handle_user_call_os(unsigned long address);
 extern int gru_user_flush_tlb(unsigned long arg);
 extern int gru_user_unload_context(unsigned long arg);
 extern int gru_get_exception_detail(unsigned long arg);
-extern int gru_set_task_slice(long address);
+extern int gru_set_context_option(unsigned long address);
 extern int gru_cpu_fault_map_id(void);
 extern struct vm_area_struct *gru_find_vma(unsigned long vaddr);
 extern void gru_flush_all_tlb(struct gru_state *gru);