--- /dev/null
+/*
+ * pmm.c - POST(Power On Self Test) Memory Manager
+ * according to the specification described in
+ * http://www.phoenix.com/NR/rdonlyres/873A00CF-33AC-4775-B77E-08E7B9754993/0/specspmm101.pdf
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Copyright (C) 2009 FUJITSU LIMITED
+ *
+ * Author: Kouya Shimura <kouya@jp.fujitsu.com>
+ */
+
+/*
+ * Algorithm:
+ *
+ * This is not a fast storage allocator but simple one. There is no
+ * segregated management by block size and it does nothing special for
+ * avoiding the fragmentation.
+ *
+ * The allocation algorithm is a first-fit. All memory blocks are
+ * managed by linear single linked list in order of the address.
+ * (i.e. There is no backward pointer) It searches the first available
+ * equal or larger block from the head (lowest address) of memory
+ * heap. The larger block is splitted into two blocks unless one side
+ * becomes too small.
+ *
+ * For de-allocation, the specified block is just marked as available
+ * and it does nothing else. Thus, the fragmentation will occur. The
+ * collection of continuous available blocks are done on the search
+ * phase of another block allocation.
+ *
+ * The following is an abstract of this algorithm. The actual code
+ * looks complicated on account of alignment and checking the handle.
+ *
+ * static memblk_t *
+ * alloc(heap_t *heap, uint32_t size)
+ * {
+ * static memblk_t *mb;
+ * for_each_memblk(heap, mb) // search memory blocks
+ * if (memblk_is_avail(mb))
+ * {
+ * collect_avail_memblks(heap, mb);
+ * if (size <= memblk_bufsize(mb))
+ * {
+ * split_memblk(mb, size);
+ * set_inuse(mb);
+ * return mb;
+ * }
+ * }
+ * return NULL;
+ * }
+ */
+
+#include <stdint.h>
+#include <stddef.h>
+#include <../hvmloader/config.h>
+#include <../hvmloader/e820.h>
+#include "util.h"
+
+#define DEBUG_PMM 0
+
+#define ASSERT(_expr, _action) \
+ if (!(_expr)) { \
+ printf("ASSERTION FAIL: %s %s:%d %s()\n", \
+ __STRING(_expr), __FILE__, __LINE__, __func__); \
+ _action; \
+ } else
+
+#if DEBUG_PMM
+# define PMM_DEBUG(format, p...) printf("PMM " format, ##p)
+#else
+# define PMM_DEBUG(format, p...)
+#endif
+
+struct pmmAllocArgs {
+ uint16_t function;
+ uint32_t length;
+ uint32_t handle;
+ uint16_t flags;
+} __attribute__ ((packed));
+
+struct pmmFindArgs {
+ uint16_t function;
+ uint32_t handle;
+} __attribute__ ((packed));
+
+struct pmmDeallocateArgs {
+ uint16_t function;
+ uint32_t buffer;
+} __attribute__ ((packed));
+
+#define PMM_FUNCTION_ALLOCATE 0
+#define PMM_FUNCTION_FIND 1
+#define PMM_FUNCTION_DEALLOC 2
+
+#define PARAGRAPH_LENGTH 16 // unit of length
+
+#define PMM_HANDLE_ANONYMOUS 0xffffffff
+
+#define PMM_FLAGS_MEMORY_TYPE_MASK 0x0003
+#define PMM_FLAGS_MEMORY_INVALID 0
+#define PMM_FLAGS_MEMORY_CONVENTIONAL 1 // 0 to 1MB
+#define PMM_FLAGS_MEMORY_EXTENDED 2 // 1MB to 4GB
+#define PMM_FLAGS_MEMORY_ANY 3 // whichever is available
+#define PMM_FLAGS_ALIGINMENT 0x0004
+
+/* Error code */
+#define PMM_ENOMEM (0) // Out of memory, duplicate handle
+#define PMM_EINVAL (-1) // Invalid argument
+
+#define ALIGN_UP(addr, size) (((addr)+((size)-1))&(~((size)-1)))
+#define ALIGN_DOWN(addr, size) ((addr)&(~((size)-1)))
+
+typedef struct memblk {
+ uint32_t magic; // inuse or available
+ struct memblk *next; // points the very next of this memblk
+ uint32_t handle; // identifier of this block
+ uint32_t __fill; // for 16byte alignment, not used
+ uint8_t buffer[0];
+} memblk_t;
+
+typedef struct heap {
+ memblk_t *head; // start address of heap
+ memblk_t *end; // end address of heap
+} heap_t;
+
+#define HEAP_NOT_INITIALIZED (memblk_t *)-1
+#define HEAP_ALIGNMENT 16
+
+/*
+ * PMM handles two memory heaps, the caller chooses either.
+ *
+ * - conventional memroy (below 1MB)
+ * In HVM, the area is fixed. 0x00010000-0x0007FFFF
+ * (from SCRATCH_PHYSICAL_ADDRESS to HYPERCALL_PHYSICAL_ADDRESS)
+ *
+ * - extended memory (start at 1MB, below 4GB)
+ * In HVM, the area starts at memory address 0x00100000.
+ * The end address is variable. We read low RAM address from e820 table.
+ *
+ * The following struct must be located in the data segment since bss
+ * in 32bitbios doesn't be relocated.
+ */
+static struct {
+ heap_t heap; // conventional memory
+ heap_t ext_heap; // extended memory
+} pmm_data = { {HEAP_NOT_INITIALIZED, NULL}, {NULL, NULL} };
+
+/* These values are private use, not a spec in PMM */
+#define MEMBLK_MAGIC_INUSE 0x2A4D4D50 // 'PMM*'
+#define MEMBLK_MAGIC_AVAIL 0x5F4D4D50 // 'PMM_'
+
+#define memblk_is_inuse(_mb) ((_mb)->magic == MEMBLK_MAGIC_INUSE)
+#define memblk_is_avail(_mb) ((_mb)->magic == MEMBLK_MAGIC_AVAIL)
+
+static void set_inuse(memblk_t *mb, uint32_t handle)
+{
+ mb->magic = MEMBLK_MAGIC_INUSE;
+ mb->handle = handle;
+}
+
+static void set_avail(memblk_t *mb)
+{
+ mb->magic = MEMBLK_MAGIC_AVAIL;
+ mb->handle = PMM_HANDLE_ANONYMOUS;
+}
+
+#define MEMBLK_HEADER_SIZE ((int)(&((memblk_t *)0)->buffer))
+#define MIN_MEMBLK_SIZE (MEMBLK_HEADER_SIZE + PARAGRAPH_LENGTH)
+
+#define memblk_size(_mb) ((void *)((_mb)->next) - (void *)(_mb))
+#define memblk_buffer(_mb) ((uint32_t)(&(_mb)->buffer))
+#define memblk_bufsize(_mb) (memblk_size(_mb) - MEMBLK_HEADER_SIZE)
+
+#define buffer_memblk(_buf) (memblk_t *)((_buf) - MEMBLK_HEADER_SIZE)
+
+#define memblk_loop_mbondition(_h, _mb) \
+ (((_mb) < (_h)->end) && (/* avoid infinite loop */ (_mb) < (_mb)->next))
+
+#define for_each_memblk(_h, _mb) \
+ for ((_mb) = (_h)->head; \
+ memblk_loop_mbondition(_h, _mb); \
+ (_mb) = (_mb)->next)
+
+#define for_remain_memblk(_h, _mb) \
+ for (; \
+ memblk_loop_mbondition(_h, _mb); \
+ (_mb) = (_mb)->next)
+
+/*
+ * <-size->
+ * +==================+======+ +========+========+======+
+ * | avail | | | avail | avail | |
+ * | memblk |memblk|... | memblk | memblk |memblk|...
+ * +==================+======+ => +========+========+======+
+ * ^ | ^ | ^ | ^ | ^ | ^
+ * | |next | |next| |next | |next | |next|
+ * | \________________/ \____/ \______/ \______/ \____/
+ * | ^
+ * | |
+ * mb +- sb(return value)
+ */
+static memblk_t *
+split_memblk(memblk_t *mb, uint32_t size)
+{
+ memblk_t *sb = (void *)memblk_buffer(mb) + size;
+
+ /* Only split if the remaining fragment is big enough. */
+ if ( (memblk_bufsize(mb) - size) < MIN_MEMBLK_SIZE)
+ return mb;
+
+ sb->next = mb->next;
+ set_avail(sb);
+
+ mb->next = sb;
+ return sb;
+}
+
+/*
+ * +======+======+======+======+ +=================+======+
+ * |avail |avail |avail |inuse | | avail |inuse |
+ * |memblk|memblk|memblk|memblk|... | memblk |memblk|...
+ * +======+======+======+======+ => +=================+======+
+ * ^ | ^ | ^ | ^ | ^ | ^ | ^
+ * | |next| |next| |next| |next| |next | |next|
+ * | \____/ \____/ \____/ \____/ \_______________/ \____/
+ * |
+ * mb
+ */
+static void
+collect_avail_memblks(heap_t *heap, memblk_t *mb)
+{
+ memblk_t *nb = mb->next;
+
+ for_remain_memblk ( heap, nb )
+ if ( memblk_is_inuse(nb) )
+ break;
+ mb->next = nb;
+}
+
+static void
+pmm_init_heap(heap_t *heap, uint32_t from_addr, uint32_t to_addr)
+{
+ memblk_t *mb = (memblk_t *)ALIGN_UP(from_addr, HEAP_ALIGNMENT);
+
+ mb->next = (memblk_t *)ALIGN_DOWN(to_addr, HEAP_ALIGNMENT);
+ set_avail(mb);
+
+ heap->head = mb;
+ heap->end = mb->next;
+}
+
+static void
+pmm_initalize(void)
+{
+ int i, e820_nr = *E820_NR;
+ struct e820entry *e820 = E820;
+
+ /* Extended memory: RAM below 4GB, 0x100000-0xXXXXXXXX */
+ for ( i = 0; i < e820_nr; i++ )
+ {
+ if ( (e820[i].type == E820_RAM) && (e820[i].addr >= 0x00100000) )
+ {
+ pmm_init_heap(&pmm_data.ext_heap, e820[i].addr,
+ e820[i].addr + e820[i].size);
+ break;
+ }
+ }
+
+ /* convectional memory: RAM below 1MB, 0x10000-0x7FFFF */
+ pmm_init_heap(&pmm_data.heap, SCRATCH_PHYSICAL_ADDRESS,
+ HYPERCALL_PHYSICAL_ADDRESS);
+}
+
+static uint32_t
+pmm_max_avail_length(heap_t *heap)
+{
+ memblk_t *mb;
+ uint32_t size, max = 0;
+
+ for_each_memblk ( heap, mb )
+ {
+ if ( !memblk_is_avail(mb) )
+ continue;
+ collect_avail_memblks(heap, mb);
+ size = memblk_bufsize(mb);
+ if ( size > max )
+ max = size;
+ }
+
+ return (max / PARAGRAPH_LENGTH);
+}
+
+static memblk_t *
+first_fit(heap_t *heap, uint32_t size, uint32_t handle, uint32_t flags)
+{
+ memblk_t *mb;
+ int32_t align = 0;
+
+ if ( flags & PMM_FLAGS_ALIGINMENT )
+ align = ((size ^ (size - 1)) >> 1) + 1;
+
+ for_each_memblk ( heap, mb )
+ {
+ if ( memblk_is_avail(mb) )
+ {
+ collect_avail_memblks(heap, mb);
+
+ if ( align )
+ {
+ uint32_t addr = memblk_buffer(mb);
+ uint32_t offset = ALIGN_UP(addr, align) - addr;
+
+ if ( offset > 0 )
+ {
+ ASSERT(offset >= MEMBLK_HEADER_SIZE, continue);
+
+ if ( (offset + size) > memblk_bufsize(mb) )
+ continue;
+
+ mb = split_memblk(mb, offset - MEMBLK_HEADER_SIZE);
+ return mb;
+ }
+ }
+
+ if ( size <= memblk_bufsize(mb) )
+ return mb;
+ }
+ else
+ {
+ ASSERT(memblk_is_inuse(mb), return NULL);
+
+ /* Duplication check for handle. */
+ if ( (handle != PMM_HANDLE_ANONYMOUS) && (mb->handle == handle) )
+ return NULL;
+ }
+ }
+
+ return NULL;
+}
+
+static memblk_t *
+pmm_find_handle(heap_t *heap, uint32_t handle)
+{
+ memblk_t *mb;
+
+ if ( handle == PMM_HANDLE_ANONYMOUS )
+ return NULL;
+
+ for_each_memblk ( heap, mb )
+ if ( mb->handle == handle )
+ return mb;
+
+ return NULL;
+}
+
+/*
+ * allocate a memory block of the specified type and size, and returns
+ * the address of the memory block.
+ *
+ * A client-specified identifier to be associated with the allocated
+ * memory block. A handle of 0xFFFFFFFF indicates that no identifier
+ * should be associated with the block. Such a memory block is known
+ * as an "anonymous" memory block and cannot be found using the
+ * pmmFind function. If a specified handle for a requested memory
+ * block is already used in a currently allocated memory block, the
+ * error value of 0x00000000 is returned
+ *
+ * If length is 0x00000000, no memory is allocated and the value
+ * returned is the size of the largest memory block available for the
+ * memory type specified in the flags parameter. The alignment bit in
+ * the flags register is ignored when calculating the largest memory
+ * block available.
+ *
+ * If a specified handle for a requested memory block is already used
+ * in a currently allocated memory block, the error value of
+ * 0x00000000 is returned.
+ *
+ * A return value of 0x00000000 indicates that an error occurred and
+ * no memory has been allocated.
+ */
+static uint32_t
+pmmAllocate(uint32_t length, uint32_t handle, uint16_t flags)
+{
+ heap_t *heap;
+ memblk_t *mb;
+ uint32_t size;
+
+ switch ( flags & PMM_FLAGS_MEMORY_TYPE_MASK )
+ {
+ case PMM_FLAGS_MEMORY_CONVENTIONAL:
+ heap = &pmm_data.heap;
+ break;
+
+ case PMM_FLAGS_MEMORY_EXTENDED:
+ case PMM_FLAGS_MEMORY_ANY: /* XXX: ignore conventional memory for now */
+ heap = &pmm_data.ext_heap;
+ break;
+
+ default:
+ return PMM_EINVAL;
+ }
+
+ /* return the largest memory block available */
+ if ( length == 0 )
+ return pmm_max_avail_length(heap);
+
+ size = length * PARAGRAPH_LENGTH;
+ mb = first_fit(heap, size, handle, flags);
+
+ if ( mb == NULL )
+ return PMM_ENOMEM;
+
+ /* duplication check for handle */
+ if ( handle != PMM_HANDLE_ANONYMOUS )
+ {
+ memblk_t *nb = mb->next;
+
+ for_remain_memblk(heap, nb)
+ if (nb->handle == handle)
+ return PMM_ENOMEM;
+ }
+
+ split_memblk(mb, size);
+ set_inuse(mb, handle);
+
+ return memblk_buffer(mb);
+}
+
+/*
+ * returns the address of the memory block associated with the
+ * specified handle.
+ *
+ * A return value of 0x00000000 indicates that the handle does not
+ * correspond to a currently allocated memory block.
+ */
+static uint32_t
+pmmFind(uint32_t handle)
+{
+ memblk_t *mb;
+
+ if ( handle == PMM_HANDLE_ANONYMOUS )
+ return 0;
+
+ mb = pmm_find_handle(&pmm_data.heap, handle);
+ if ( mb == NULL )
+ mb = pmm_find_handle(&pmm_data.ext_heap, handle);
+
+ return mb ? memblk_buffer(mb) : 0;
+}
+
+/*
+ * frees the specified memory block that was previously allocated by
+ * pmmAllocate.
+ *
+ * If the memory block was deallocated correctly, the return value is
+ * 0x00000000. If there was an error, the return value is non-zero.
+ */
+static uint32_t
+pmmDeallocate(uint32_t buffer)
+{
+ memblk_t *mb = buffer_memblk(buffer);
+
+ if ( !memblk_is_inuse(mb) )
+ return PMM_EINVAL;
+
+ set_avail(mb);
+ return 0;
+}
+
+
+union pmm_args {
+ uint16_t function;
+ struct pmmAllocArgs alloc;
+ struct pmmFindArgs find;
+ struct pmmDeallocateArgs dealloc;
+} __attribute__ ((packed));
+
+/*
+ * entry function of all PMM services.
+ *
+ * Values returned to the caller are placed in the DX:AX register
+ * pair. The flags and all registers, other than DX and AX, are
+ * preserved across calls to PMM services.
+ */
+uint32_t
+pmm(void *argp)
+{
+ union pmm_args *ap = argp;
+ uint32_t ret = PMM_EINVAL;
+
+ if ( pmm_data.heap.head == HEAP_NOT_INITIALIZED )
+ pmm_initalize();
+
+ switch ( ap->function )
+ {
+ case PMM_FUNCTION_ALLOCATE:
+ ret = pmmAllocate(ap->alloc.length, ap->alloc.handle, ap->alloc.flags);
+ PMM_DEBUG("Alloc length=%x handle=%x flags=%x ret=%x\n",
+ ap->alloc.length, ap->alloc.handle, ap->alloc.flags, ret);
+ break;
+
+ case PMM_FUNCTION_FIND:
+ ret = pmmFind(ap->find.handle);
+ PMM_DEBUG("Find handle=%x ret=%x\n", ap->find.handle, ret);
+ break;
+
+ case PMM_FUNCTION_DEALLOC:
+ ret = pmmDeallocate(ap->dealloc.buffer);
+ PMM_DEBUG("Dealloc buffer=%x ret=%x\n", ap->dealloc.buffer, ret);
+ break;
+
+ default:
+ PMM_DEBUG("Invalid function:%d\n", ap->function);
+ break;
+ }
+
+ return ret;
+}
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