Changeset e49e234 in mainline for kernel/generic

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()

Location:

kernel/generic

Files:

• include/align.h (modified) (4 diffs)
• include/mm/frame.h (modified) (4 diffs)
• include/mm/page.h (modified) (1 diff)
• src/ddi/ddi.c (modified) (11 diffs)
• src/mm/frame.c (modified) (17 diffs)

kernel/generic/include/align.h

@@ -27 +27 @@
  */
 
-/** @addtogroup generic 
+/** @addtogroup generic
  * @ingroup others
  * @{
@@ -33 +33 @@
 /**
  * @file
- * @brief       Macros for making values and addresses aligned.
+ * @brief Macros for making values and addresses aligned.
  */
 
@@ -44 +44 @@
  * @param a Size of alignment, must be power of 2.
  */
-#define ALIGN_DOWN(s, a)        ((s) & ~((a) - 1))
+#define ALIGN_DOWN(s, a)  ((s) & ~((a) - 1))
 
 
@@ -52 +52 @@
  * @param a Size of alignment, must be power of 2.
  */
-#define ALIGN_UP(s, a)          (((s) + ((a) - 1)) & ~((a) - 1))
+#define ALIGN_UP(s, a)  (((s) + ((a) - 1)) & ~((a) - 1))
 
 #endif

kernel/generic/include/mm/frame.h

@@ -40 +40 @@
 #include <adt/list.h>
 #include <mm/buddy.h>
+#include <synch/spinlock.h>
 #include <arch/mm/page.h>
 #include <arch/mm/frame.h>
@@ -68 +69 @@
 typedef uint8_t zone_flags_t;
 
+/** Available zone (free for allocation) */
+#define ZONE_AVAILABLE  0x00
 /** Zone is reserved (not available for allocation) */
-#define ZONE_RESERVED  0x08
+#define ZONE_RESERVED   0x08
 /** Zone is used by firmware (not available for allocation) */
-#define ZONE_FIRMWARE  0x10
+#define ZONE_FIRMWARE   0x10
 
 /** Currently there is no equivalent zone flags
     for frame flags */
 #define FRAME_TO_ZONE_FLAGS(frame_flags)  0
+
+typedef struct {
+        count_t refcount;     /**< Tracking of shared frames */
+        uint8_t buddy_order;  /**< Buddy system block order */
+        link_t buddy_link;    /**< Link to the next free block inside
+                               one order */
+        void *parent;         /**< If allocated by slab, this points there */
+} frame_t;
+
+typedef struct {
+        pfn_t base;                    /**< Frame_no of the first frame
+                                        in the frames array */
+        count_t count;                 /**< Size of zone */
+        count_t free_count;            /**< Number of free frame_t
+                                        structures */
+        count_t busy_count;            /**< Number of busy frame_t
+                                        structures */
+        zone_flags_t flags;            /**< Type of the zone */
+        
+        frame_t *frames;               /**< Array of frame_t structures
+                                        in this zone */
+        buddy_system_t *buddy_system;  /**< Buddy system for the zone */
+} zone_t;
+
+/*
+ * The zoneinfo.lock must be locked when accessing zoneinfo structure.
+ * Some of the attributes in zone_t structures are 'read-only'
+ */
+typedef struct {
+        SPINLOCK_DECLARE(lock);
+        count_t count;
+        zone_t info[ZONES_MAX];
+} zones_t;
+
+extern zones_t zones;
 
 static inline uintptr_t PFN2ADDR(pfn_t frame)
@@ -99 +137 @@
 }
 
+static inline bool zone_flags_available(zone_flags_t flags)
+{
+        return ((flags & (ZONE_RESERVED | ZONE_FIRMWARE)) == 0);
+}
+
 #define IS_BUDDY_ORDER_OK(index, order) \
     ((~(((unative_t) -1) << (order)) & (index)) == 0)
@@ -118 +161 @@
 extern void frame_reference_add(pfn_t);
 
+extern count_t find_zone(pfn_t frame, count_t count, count_t hint);
 extern count_t zone_create(pfn_t, count_t, pfn_t, zone_flags_t);
 extern void *frame_get_parent(pfn_t, count_t);

kernel/generic/include/mm/page.h

@@ -62 +62 @@
 
 extern uintptr_t hw_map(uintptr_t physaddr, size_t size);
-extern void hw_area(void);
 
 #endif

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;
 }

kernel/generic/src/mm/frame.c

@@ -49 +49 @@
 #include <debug.h>
 #include <adt/list.h>
-#include <synch/spinlock.h>
 #include <synch/mutex.h>
 #include <synch/condvar.h>
@@ -61 +60 @@
 #include <config.h>
 
-typedef struct {
-        count_t refcount;     /**< Tracking of shared frames */
-        uint8_t buddy_order;  /**< Buddy system block order */
-        link_t buddy_link;    /**< Link to the next free block inside
-                               one order */
-        void *parent;         /**< If allocated by slab, this points there */
-} frame_t;
-
-typedef struct {
-        pfn_t base;                    /**< Frame_no of the first frame
-                                        in the frames array */
-        count_t count;                 /**< Size of zone */
-        count_t free_count;            /**< Number of free frame_t
-                                        structures */
-        count_t busy_count;            /**< Number of busy frame_t
-                                        structures */
-        zone_flags_t flags;            /**< Type of the zone */
-        
-        frame_t *frames;               /**< Array of frame_t structures
-                                        in this zone */
-        buddy_system_t *buddy_system;  /**< Buddy system for the zone */
-} zone_t;
-
-/*
- * The zoneinfo.lock must be locked when accessing zoneinfo structure.
- * Some of the attributes in zone_t structures are 'read-only'
- */
-typedef struct {
-        SPINLOCK_DECLARE(lock);
-        count_t count;
-        zone_t info[ZONES_MAX];
-} zones_t;
-
-static zones_t zones;
+zones_t zones;
 
 /*
@@ -127 +93 @@
 {
         return (frame - zone->frames);
-}
-
-static inline bool zone_flags_available(zone_flags_t flags)
-{
-        return ((flags & (ZONE_RESERVED | ZONE_FIRMWARE)) == 0);
 }
 
@@ -181 +142 @@
         /* Move other zones up */
         count_t j;
-        for (j = i; j < zones.count; j++)
-                zones.info[j + 1] = zones.info[j];
+        for (j = zones.count; j > i; j--) {
+                zones.info[j] = zones.info[j - 1];
+                zones.info[j].buddy_system->data =
+                    (void *) &zones.info[j - 1];
+        }
         
         zones.count++;
@@ -207 +171 @@
 }
 
-/** Find a zone with a given frame.
+/** Find a zone with a given frames.
  *
  * Assume interrupts are disabled and zones lock is
@@ -213 +177 @@
  *
  * @param frame Frame number contained in zone.
+ * @param count Number of frames to look for.
  * @param hint  Used as zone hint.
  *
@@ -218 +183 @@
  *
  */
-static count_t find_zone(pfn_t frame, count_t hint)
+count_t find_zone(pfn_t frame, count_t count, count_t hint)
 {
         if (hint >= zones.count)
@@ -226 +191 @@
         do {
                 if ((zones.info[i].base <= frame)
-                    && (zones.info[i].base + zones.info[i].count > frame))
+                    && (zones.info[i].base + zones.info[i].count >= frame + count))
                         return i;
                 
@@ -766 +731 @@
             zones.info[z2].count);
         
-        /* Shift existing zones */
+        /* Move zones down */
         count_t i;
-        for (i = z2 + 1; i < zones.count; i++)
+        for (i = z2 + 1; i < zones.count; i++) {
                 zones.info[i - 1] = zones.info[i];
+                zones.info[i - 1].buddy_system->data =
+                    (void *) &zones.info[i - 1];
+        }
+        
         zones.count--;
         
@@ -965 +934 @@
         spinlock_lock(&zones.lock);
         
-        count_t znum = find_zone(pfn, hint);
+        count_t znum = find_zone(pfn, 1, hint);
         
         ASSERT(znum != (count_t) -1);
@@ -981 +950 @@
         spinlock_lock(&zones.lock);
         
-        count_t znum = find_zone(pfn, hint);
+        count_t znum = find_zone(pfn, 1, hint);
         
         ASSERT(znum != (count_t) -1);
@@ -1112 +1081 @@
          */
         pfn_t pfn = ADDR2PFN(frame);
-        count_t znum = find_zone(pfn, NULL);
+        count_t znum = find_zone(pfn, 1, NULL);
         
         ASSERT(znum != (count_t) -1);
@@ -1151 +1120 @@
          * First, find host frame zone for addr.
          */
-        count_t znum = find_zone(pfn, NULL);
+        count_t znum = find_zone(pfn, 1, NULL);
         
         ASSERT(znum != (count_t) -1);
@@ -1169 +1138 @@
         count_t i;
         for (i = 0; i < count; i++) {
-                count_t znum = find_zone(start + i, 0);
+                count_t znum = find_zone(start + i, 1, 0);
                 if (znum == (count_t) -1)  /* PFN not found */
                         continue;
@@ -1238 +1207 @@
 {
 #ifdef __32_BITS__
-        printf("#  base address flags    free frames  busy frames\n");
-        printf("-- ------------ -------- ------------ ------------\n");
+        printf("#  base address frames       flags    free frames  busy frames\n");
+        printf("-- ------------ ------------ -------- ------------ ------------\n");
 #endif
 
 #ifdef __64_BITS__
-        printf("#  base address         flags    free frames  busy frames\n");
-        printf("-- -------------------- -------- ------------ ------------\n");
+        printf("#  base address          frames      flags    free frames  busy frames\n");
+        printf("-- -------------------- ------------ -------- ------------ ------------\n");
 #endif
         
@@ -1270 +1239 @@
                 
                 uintptr_t base = PFN2ADDR(zones.info[i].base);
+                count_t count = zones.info[i].count;
                 zone_flags_t flags = zones.info[i].flags;
                 count_t free_count = zones.info[i].free_count;
@@ -1279 +1249 @@
                 bool available = zone_flags_available(flags);
                 
+                printf("%-2" PRIc, i);
+                
 #ifdef __32_BITS__
-                printf("%-2" PRIc "   %10p %c%c%c      ", i, base,
+                printf("   %10p", base);
+#endif
+                
+#ifdef __64_BITS__
+                printf("   %18p", base);
+#endif
+                
+                printf(" %12" PRIc " %c%c%c      ", count,
                     available ? 'A' : ' ',
                     (flags & ZONE_RESERVED) ? 'R' : ' ',
                     (flags & ZONE_FIRMWARE) ? 'F' : ' ');
-#endif
-                
-#ifdef __64_BITS__
-                printf("%-2" PRIc "   %18p %c%c%c      ", i, base,
-                    available ? 'A' : ' ',
-                    (flags & ZONE_RESERVED) ? 'R' : ' ',
-                    (flags & ZONE_FIRMWARE) ? 'F' : ' ');
-#endif
                 
                 if (available)
                         printf("%12" PRIc " %12" PRIc,
                             free_count, busy_count);
+                
                 printf("\n");
         }