Changeset e49e234 in mainline for kernel/generic/src/ddi

Timestamp:

2009-02-27T11:32:31Z (17 years ago)

Author:

Martin Decky <martin@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

c1f7f6ea

Parents:

5f0f29ce

Message:

kernel memory management revisited (phase 2): map physical memory according to zones

• ia32: register reserved and ACPI zones
• pareas are now used only for mapping of present physical memory (hw_area() is gone)
• firmware zones and physical addresses outside any zones are allowed to be mapped generally
• fix nasty antient bug in zones_insert_zone()

File:

• kernel/generic/src/ddi/ddi.c (modified) (11 diffs)

kernel/generic/src/ddi/ddi.c

@@ -30 +30 @@
  * @{
  */
- 
+
 /**
  * @file
- * @brief       Device Driver Interface functions.
+ * @brief Device Driver Interface functions.
  *
  * This file contains functions that comprise the Device Driver Interface.
@@ -48 +48 @@
 #include <synch/spinlock.h>
 #include <syscall/copy.h>
-#include <adt/list.h>
+#include <adt/btree.h>
 #include <arch.h>
 #include <align.h>
@@ -56 +56 @@
 SPINLOCK_INITIALIZE(parea_lock);
 
-/** List with enabled physical memory areas. */
-static LIST_INITIALIZE(parea_head);
+/** B+tree with enabled physical memory areas. */
+static btree_t parea_btree;
 
 /** Initialize DDI. */
 void ddi_init(void)
 {
-        hw_area();
+        btree_create(&parea_btree);
 }
 
@@ -69 +69 @@
  * @param parea Pointer to physical area structure.
  *
- * @todo This function doesn't check for overlaps. It depends on the kernel to
- * create disjunct physical memory areas.
  */
 void ddi_parea_register(parea_t *parea)
 {
-        ipl_t ipl;
-        
-        ipl = interrupts_disable();
+        ipl_t ipl = interrupts_disable();
         spinlock_lock(&parea_lock);
         
         /*
-         * TODO: we should really check for overlaps here.
-         * However, we should be safe because the kernel is pretty sane.
-         */
-        link_initialize(&parea->link);
-        list_append(&parea->link, &parea_head);
+         * We don't check for overlaps here as the kernel is pretty sane.
+         */
+        btree_insert(&parea_btree, (btree_key_t) parea->pbase, parea, NULL);
         
         spinlock_unlock(&parea_lock);
@@ -92 +86 @@
 /** Map piece of physical memory into virtual address space of current task.
  *
- * @param pf Physical address of the starting frame.
- * @param vp Virtual address of the starting page.
+ * @param pf    Physical address of the starting frame.
+ * @param vp    Virtual address of the starting page.
  * @param pages Number of pages to map.
  * @param flags Address space area flags for the mapping.
  *
  * @return 0 on success, EPERM if the caller lacks capabilities to use this
- *  syscall, ENOENT if there is no task matching the specified ID or the
- *  physical address space is not enabled for mapping and ENOMEM if there
- *  was a problem in creating address space area.
- */
-static int ddi_physmem_map(uintptr_t pf, uintptr_t vp, pfn_t pages, int flags)
-{
-        ipl_t ipl;
-        cap_t caps;
+ *         syscall, EBADMEM if pf or vf is not page aligned, ENOENT if there
+ *         is no task matching the specified ID or the physical address space
+ *         is not enabled for mapping and ENOMEM if there was a problem in
+ *         creating address space area.
+ *
+ */
+static int ddi_physmem_map(uintptr_t pf, uintptr_t vp, count_t pages, int flags)
+{
+        ASSERT(TASK);
+        ASSERT((pf % FRAME_SIZE) == 0);
+        ASSERT((vp % PAGE_SIZE) == 0);
+        
+        /*
+         * Make sure the caller is authorised to make this syscall.
+         */
+        cap_t caps = cap_get(TASK);
+        if (!(caps & CAP_MEM_MANAGER))
+                return EPERM;
+        
         mem_backend_data_t backend_data;
-        
         backend_data.base = pf;
         backend_data.frames = pages;
         
-        /*
-         * Make sure the caller is authorised to make this syscall.
-         */
-        caps = cap_get(TASK);
-        if (!(caps & CAP_MEM_MANAGER))
-                return EPERM;
-        
-        ipl = interrupts_disable();
-        
-        /*
-         * Check if the physical memory area is enabled for mapping.
-         */
-        spinlock_lock(&parea_lock);
-        
-        bool fnd = false;
-        link_t *cur;
-        
-        for (cur = parea_head.next; cur != &parea_head; cur = cur->next) {
-                parea_t *parea = list_get_instance(cur, parea_t, link);
-                if ((parea->pbase <= pf) && (ADDR2PFN(pf - parea->pbase) + pages <= parea->frames)) {
-                        fnd = true;
-                        break;
-                }
-        }
-        
-        spinlock_unlock(&parea_lock);
-        
-        if (!fnd) {
-                /*
-                 * Physical memory area cannot be mapped.
-                 */
-                interrupts_restore(ipl);
-                return ENOENT;
-        }
-        
+        ipl_t ipl = interrupts_disable();
+        
+        /* Find the zone of the physical memory */
+        spinlock_lock(&zones.lock);
+        count_t znum = find_zone(ADDR2PFN(pf), pages, 0);
+        
+        if (znum == (count_t) -1) {
+                /* Frames not found in any zones
+                 * -> assume it is hardware device and allow mapping
+                 */
+                spinlock_unlock(&zones.lock);
+                goto map;
+        }
+        
+        if (zones.info[znum].flags & ZONE_FIRMWARE) {
+                /* Frames are part of firmware */
+                spinlock_unlock(&zones.lock);
+                goto map;
+        }
+        
+        if (zone_flags_available(zones.info[znum].flags)) {
+                /* Frames are part of physical memory, check if the memory
+                 * region is enabled for mapping.
+                 */
+                spinlock_unlock(&zones.lock);
+                
+                spinlock_lock(&parea_lock);
+                btree_node_t *nodep;
+                parea_t *parea = (parea_t *) btree_search(&parea_btree,
+                    (btree_key_t) pf, &nodep);
+                
+                if ((!parea) || (parea->frames < pages))
+                        goto err;
+                
+                spinlock_unlock(&parea_lock);
+                goto map;
+        }
+        
+err:
+        spinlock_unlock(&zones.lock);
+        interrupts_restore(ipl);
+        return ENOENT;
+        
+map:
         spinlock_lock(&TASK->lock);
         
-        if (!as_area_create(TASK->as, flags, pages * PAGE_SIZE, vp, AS_AREA_ATTR_NONE,
-                &phys_backend, &backend_data)) {
+        if (!as_area_create(TASK->as, flags, pages * PAGE_SIZE, vp,
+            AS_AREA_ATTR_NONE, &phys_backend, &backend_data)) {
                 /*
                  * The address space area could not have been created.
@@ -175 +188 @@
  *
  * @return 0 on success, EPERM if the caller lacks capabilities to use this
- *      syscall, ENOENT if there is no task matching the specified ID.
+ *           syscall, ENOENT if there is no task matching the specified ID.
+ *
  */
 static int ddi_iospace_enable(task_id_t id, uintptr_t ioaddr, size_t size)
 {
-        ipl_t ipl;
-        cap_t caps;
-        task_t *t;
-        int rc;
-        
         /*
          * Make sure the caller is authorised to make this syscall.
          */
-        caps = cap_get(TASK);
+        cap_t caps = cap_get(TASK);
         if (!(caps & CAP_IO_MANAGER))
                 return EPERM;
         
-        ipl = interrupts_disable();
+        ipl_t ipl = interrupts_disable();
         spinlock_lock(&tasks_lock);
         
-        t = task_find_by_id(id);
-        
-        if ((!t) || (!context_check(CONTEXT, t->context))) {
+        task_t *task = task_find_by_id(id);
+        
+        if ((!task) || (!context_check(CONTEXT, task->context))) {
                 /*
                  * There is no task with the specified ID
@@ -206 +215 @@
                 return ENOENT;
         }
-
+        
         /* Lock the task and release the lock protecting tasks_btree. */
-        spinlock_lock(&t->lock);
+        spinlock_lock(&task->lock);
         spinlock_unlock(&tasks_lock);
-
-        rc = ddi_iospace_enable_arch(t, ioaddr, size);
-        
-        spinlock_unlock(&t->lock);
-        interrupts_restore(ipl);
+        
+        int rc = ddi_iospace_enable_arch(task, ioaddr, size);
+        
+        spinlock_unlock(&task->lock);
+        interrupts_restore(ipl);
+        
         return rc;
 }
@@ -226 +236 @@
  *
  * @return 0 on success, otherwise it returns error code found in errno.h
- */ 
+ *
+ */
 unative_t sys_physmem_map(unative_t phys_base, unative_t virt_base,
     unative_t pages, unative_t flags)
@@ -232 +243 @@
         return (unative_t) ddi_physmem_map(ALIGN_DOWN((uintptr_t) phys_base,
             FRAME_SIZE), ALIGN_DOWN((uintptr_t) virt_base, PAGE_SIZE),
-            (pfn_t) pages, (int) flags);
+            (count_t) pages, (int) flags);
 }
 
@@ -240 +251 @@
  *
  * @return 0 on success, otherwise it returns error code found in errno.h
- */ 
+ *
+ */
 unative_t sys_iospace_enable(ddi_ioarg_t *uspace_io_arg)
 {
         ddi_ioarg_t arg;
-        int rc;
-        
-        rc = copy_from_uspace(&arg, uspace_io_arg, sizeof(ddi_ioarg_t));
+        int rc = copy_from_uspace(&arg, uspace_io_arg, sizeof(ddi_ioarg_t));
         if (rc != 0)
                 return (unative_t) rc;
-                
+        
         return (unative_t) ddi_iospace_enable((task_id_t) arg.task_id,
             (uintptr_t) arg.ioaddr, (size_t) arg.size);
@@ -257 +267 @@
  *
  * @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.
+ *               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;
 }