#include <stdint.h>
#include <string.h>
#include <errno.h>
+#include <assert.h>
#include <realmode.h>
#include <bios.h>
#include <memsizes.h>
#include <ipxe/io.h>
+#include <ipxe/memmap.h>
/**
* @file
* @ret extmem Extended memory size, in kB
*
* Note that this is only an approximation; for an accurate picture,
- * use the E820 memory map obtained via get_memmap();
+ * use the E820 memory map obtained via memmap_describe();
*/
unsigned int extmemsize ( void ) {
unsigned int extmem_e801;
/**
* Get e820 memory map
*
- * @v memmap Memory map to fill in
+ * @v region Memory region of interest to be updated
* @ret rc Return status code
*/
-static int meme820 ( struct memory_map *memmap ) {
- struct memory_region *region = memmap->regions;
- struct memory_region *prev_region = NULL;
+static int meme820 ( struct memmap_region *region ) {
+ unsigned int count = 0;
+ uint64_t start = 0;
+ uint64_t len = 0;
uint32_t next = 0;
uint32_t smap;
uint32_t size;
break;
}
- /* If first region is not RAM, assume map is invalid */
- if ( ( memmap->count == 0 ) &&
- ( e820buf.type != E820_TYPE_RAM ) ) {
- DBG ( "INT 15,e820 failed, first entry not RAM\n" );
- return -EINVAL;
- }
-
DBG ( "INT 15,e820 region [%llx,%llx) type %d",
e820buf.start, ( e820buf.start + e820buf.len ),
( int ) e820buf.type );
continue;
}
- region->start = e820buf.start;
- region->end = e820buf.start + e820buf.len;
-
/* Check for adjacent regions and merge them */
- if ( prev_region && ( region->start == prev_region->end ) ) {
- prev_region->end = region->end;
+ if ( e820buf.start == ( start + len ) ) {
+ len += e820buf.len;
} else {
- prev_region = region;
- region++;
- memmap->count++;
+ start = e820buf.start;
+ len = e820buf.len;
}
- if ( memmap->count >= ( sizeof ( memmap->regions ) /
- sizeof ( memmap->regions[0] ) ) ) {
- DBG ( "INT 15,e820 too many regions returned\n" );
- /* Not a fatal error; what we've got so far at
- * least represents valid regions of memory,
- * even if we couldn't get them all.
- */
- break;
+ /* Sanity check: first region (base memory) should
+ * start at address zero.
+ */
+ if ( ( count == 0 ) && ( start != 0 ) ) {
+ DBG ( "INT 15,e820 region 0 starts at %llx (expected "
+ "0); assuming insane\n", start );
+ return -EINVAL;
+ }
+
+ /* Sanity check: second region (extended memory)
+ * should start at address 0x100000.
+ */
+ if ( ( count == 1 ) && ( start != 0x100000 ) ) {
+ DBG ( "INT 15,e820 region 1 starts at %llx (expected "
+ "100000); assuming insane\n", start );
+ return -EINVAL;
}
+
+ /* Update region of interest */
+ memmap_update ( region, start, len, MEMMAP_FL_MEMORY, "e820" );
+ count++;
+
} while ( next != 0 );
/* Sanity checks. Some BIOSes report complete garbage via INT
* region (starting at 0) and at least one high memory region
* (starting at 0x100000).
*/
- if ( memmap->count < 2 ) {
+ if ( count < 2 ) {
DBG ( "INT 15,e820 returned only %d regions; assuming "
- "insane\n", memmap->count );
- return -EINVAL;
- }
- if ( memmap->regions[0].start != 0 ) {
- DBG ( "INT 15,e820 region 0 starts at %llx (expected 0); "
- "assuming insane\n", memmap->regions[0].start );
- return -EINVAL;
- }
- if ( memmap->regions[1].start != 0x100000 ) {
- DBG ( "INT 15,e820 region 1 starts at %llx (expected 100000); "
- "assuming insane\n", memmap->regions[0].start );
+ "insane\n", count );
return -EINVAL;
}
}
/**
- * Get memory map
+ * Describe memory region from system memory map
*
- * @v memmap Memory map to fill in
+ * @v addr Address within region
+ * @v hide Hide in-use regions from the memory map
+ * @v region Region descriptor to fill in
*/
-void x86_get_memmap ( struct memory_map *memmap ) {
- unsigned int basemem, extmem;
+static void int15_describe ( uint64_t addr, int hide,
+ struct memmap_region *region ) {
+ unsigned int basemem;
+ unsigned int extmem;
+ uint64_t inaccessible;
int rc;
- DBG ( "Fetching system memory map\n" );
+ /* Initialise region */
+ memmap_init ( addr, region );
- /* Clear memory map */
- memset ( memmap, 0, sizeof ( *memmap ) );
+ /* Mark addresses above 4GB as inaccessible: we have no way to
+ * access them either in a 32-bit build or in a 64-bit build
+ * (since the 64-bit build identity-maps only the 32-bit
+ * address space).
+ */
+ inaccessible = ( 1ULL << 32 );
+ memmap_update ( region, inaccessible, -inaccessible,
+ MEMMAP_FL_INACCESSIBLE, NULL );
- /* Get base and extended memory sizes */
- basemem = basememsize();
- DBG ( "FBMS base memory size %d kB [0,%x)\n",
- basemem, ( basemem * 1024 ) );
- extmem = extmemsize();
-
- /* Try INT 15,e820 first */
- if ( ( rc = meme820 ( memmap ) ) == 0 ) {
+ /* Enable/disable INT 15 interception as applicable */
+ int15_intercept ( hide );
+
+ /* Try INT 15,e820 first, falling back to constructing a map
+ * from basemem and extmem sizes
+ */
+ if ( ( rc = meme820 ( region ) ) == 0 ) {
DBG ( "Obtained system memory map via INT 15,e820\n" );
- return;
+ } else {
+ basemem = basememsize();
+ DBG ( "FBMS base memory size %d kB [0,%x)\n",
+ basemem, ( basemem * 1024 ) );
+ extmem = extmemsize();
+ memmap_update ( region, 0, ( basemem * 1024 ),
+ MEMMAP_FL_MEMORY, "basemem" );
+ memmap_update ( region, 0x100000, ( extmem * 1024 ),
+ MEMMAP_FL_MEMORY, "extmem" );
}
- /* Fall back to constructing a map from basemem and extmem sizes */
- DBG ( "INT 15,e820 failed; constructing map\n" );
- memmap->regions[0].end = ( basemem * 1024 );
- memmap->regions[1].start = 0x100000;
- memmap->regions[1].end = 0x100000 + ( extmem * 1024 );
- memmap->count = 2;
+ /* Restore INT 15 interception */
+ int15_intercept ( 1 );
}
-PROVIDE_IOAPI ( x86, get_memmap, x86_get_memmap );
+PROVIDE_MEMMAP ( int15, memmap_describe, int15_describe );
projects / thirdparty / ipxe.git / commitdiff
