Changes in / [5203efb1:76e1121f] in mainline

Files:

• kernel/generic/include/ddi/ddi.h (modified) (1 diff)
• kernel/generic/include/security/cap.h (modified) (1 diff)
• kernel/generic/include/syscall/syscall.h (modified) (1 diff)
• kernel/generic/src/ddi/ddi.c (modified) (1 diff)
• kernel/generic/src/main/kinit.c (modified) (1 diff)
• kernel/generic/src/syscall/syscall.c (modified) (1 diff)
• uspace/app/trace/syscalls.c (modified) (1 diff)
• uspace/lib/c/generic/ddi.c (modified) (1 diff)
• uspace/lib/c/include/ddi.h (modified) (1 diff)
• uspace/srv/fs/fat/fat_fat.c (modified) (1 diff)

kernel/generic/include/ddi/ddi.h

@@ -54 +54 @@
 extern unative_t sys_physmem_map(unative_t, unative_t, unative_t, unative_t);
 extern unative_t sys_iospace_enable(ddi_ioarg_t *);
+extern unative_t sys_preempt_control(int);
 
 /*

kernel/generic/include/security/cap.h

@@ -70 +70 @@
 
 /**
+ * CAP_PREEMPT_CONTROL allows its holder to disable/enable preemption.
+ */
+#define CAP_PREEMPT_CONTROL     (1<<3)
+
+/**
  * CAP_IRQ_REG entitles its holder to register IRQ handlers.
  */
-#define CAP_IRQ_REG             (1<<3) 
+#define CAP_IRQ_REG             (1<<4) 
 
 typedef uint32_t cap_t;

kernel/generic/include/syscall/syscall.h

@@ -80 +80 @@
         SYS_PHYSMEM_MAP,
         SYS_IOSPACE_ENABLE,
+        SYS_PREEMPT_CONTROL,
         
         SYS_SYSINFO_GET_TAG,

kernel/generic/src/ddi/ddi.c

@@ -258 +258 @@
 }
 
+/** Disable or enable preemption.
+ *
+ * @param enable If non-zero, the preemption counter will be decremented,
+ *               leading to potential enabling of preemption. Otherwise
+ *               the preemption counter will be incremented, preventing
+ *               preemption from occurring.
+ *
+ * @return Zero on success or EPERM if callers capabilities are not sufficient.
+ *
+ */
+unative_t sys_preempt_control(int enable)
+{
+        if (!(cap_get(TASK) & CAP_PREEMPT_CONTROL))
+                return EPERM;
+        
+        if (enable)
+                preemption_enable();
+        else
+                preemption_disable();
+        
+        return 0;
+}
+
 /** @}
  */

kernel/generic/src/main/kinit.c

@@ -208 +208 @@
                          */
                         cap_set(programs[i].task, CAP_CAP | CAP_MEM_MANAGER |
-                            CAP_IO_MANAGER | CAP_IRQ_REG);
+                            CAP_IO_MANAGER | CAP_PREEMPT_CONTROL | CAP_IRQ_REG);
                         
                         if (!ipc_phone_0)

kernel/generic/src/syscall/syscall.c

@@ -159 +159 @@
         (syshandler_t) sys_physmem_map,
         (syshandler_t) sys_iospace_enable,
+        (syshandler_t) sys_preempt_control,
         
         /* Sysinfo syscalls */

uspace/app/trace/syscalls.c

@@ -73 +73 @@
     [SYS_PHYSMEM_MAP] = { "physmem_map",                4,      V_ERRNO },
     [SYS_IOSPACE_ENABLE] = { "iospace_enable",          1,      V_ERRNO },
+    [SYS_PREEMPT_CONTROL] = { "preempt_control",        1,      V_ERRNO },
 
     [SYS_SYSINFO_GET_TAG] = { "sysinfo_get_tag",                2,      V_INTEGER },

uspace/lib/c/generic/ddi.c

@@ -96 +96 @@
 }
 
+/** Interrupt control
+ *
+ * @param enable        1 - enable interrupts, 0 - disable interrupts
+ */
+int preemption_control(int enable)
+{
+        return __SYSCALL1(SYS_PREEMPT_CONTROL, (sysarg_t) enable);
+}
+
 /** Enable PIO for specified I/O range.
  *

uspace/lib/c/include/ddi.h

@@ -41 +41 @@
 extern int physmem_map(void *, void *, unsigned long, int);
 extern int iospace_enable(task_id_t, void *, unsigned long);
+extern int preemption_control(int);
 extern int pio_enable(void *, size_t, void **);
 

uspace/srv/fs/fat/fat_fat.c

@@ -545 +545 @@
         dev_handle_t dev_handle = nodep->idx->dev_handle;
         fat_cluster_t lastc;
+        uint16_t numc;
         uint8_t fatno;
         int rc;
 
-        if (nodep->firstc == FAT_CLST_RES0) {
-                /* No clusters allocated to the node yet. */
-                nodep->firstc = mcl;
-                nodep->dirty = true;    /* need to sync node */
+        if (nodep->lastc_cached_valid) {
+                lastc = nodep->lastc_cached_value;
+                nodep->lastc_cached_valid = false;
         } else {
-                if (nodep->lastc_cached_valid) {
-                        lastc = nodep->lastc_cached_value;
-                        nodep->lastc_cached_valid = false;
-                } else {
-                        rc = fat_cluster_walk(bs, dev_handle, nodep->firstc,
-                            &lastc, NULL, (uint16_t) -1);
-                        if (rc != EOK)
-                                return rc;
+                rc = fat_cluster_walk(bs, dev_handle, nodep->firstc, &lastc,
+                    &numc, (uint16_t) -1);
+                if (rc != EOK)
+                        return rc;
+
+                if (numc == 0) {
+                        /* No clusters allocated to the node yet. */
+                        nodep->firstc = mcl;
+                        nodep->dirty = true;    /* need to sync node */
+                        return EOK;
                 }
-
-                for (fatno = FAT1; fatno < bs->fatcnt; fatno++) {
-                        rc = fat_set_cluster(bs, nodep->idx->dev_handle, fatno,
-                            lastc, mcl);
-                        if (rc != EOK)
-                                return rc;
-                }
+        }
+
+        for (fatno = FAT1; fatno < bs->fatcnt; fatno++) {
+                rc = fat_set_cluster(bs, nodep->idx->dev_handle, fatno, lastc,
+                    mcl);
+                if (rc != EOK)
+                        return rc;
         }