diff options
Diffstat (limited to 'kern/bootmem.h')
| -rw-r--r-- | kern/bootmem.h | 29 |
1 files changed, 16 insertions, 13 deletions
diff --git a/kern/bootmem.h b/kern/bootmem.h index 0c4018fd..26ac2582 100644 --- a/kern/bootmem.h +++ b/kern/bootmem.h @@ -1,5 +1,5 @@ /* - * Copyright (c) 2010-2017 Richard Braun. + * Copyright (c) 2017 Richard Braun. * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by @@ -15,7 +15,11 @@ * along with this program. If not, see <http://www.gnu.org/licenses/>. * * - * Early page allocator. + * This module provides memory-related services at bootstrap, before + * paging is enabled. In particular : + * - zone registration + * - memory allocation (mainly for page tables) + * - boot data reservation */ #ifndef _KERN_BOOTMEM_H @@ -54,8 +58,8 @@ void bootmem_register_zone(unsigned int zone_index, bool direct_mapped, * * The kernel is automatically reserved. * - * Once all reserved ranges have been registered, the user can initialize the - * early page allocator. + * Once all reserved ranges have been registered, the user can initialize + * the module. * * If the range is marked temporary, it will be unregistered once * the boot data have been saved/consumed so that their backing @@ -68,7 +72,7 @@ void bootmem_reserve_range(phys_addr_t start, phys_addr_t end, bool temporary); /* * Initialize the early page allocator. * - * This function builds a heap based on the registered zones while carefuling + * This function builds a heap based on the registered zones while carefully * avoiding reserved data. * * This function is called before paging is enabled. @@ -76,20 +80,19 @@ void bootmem_reserve_range(phys_addr_t start, phys_addr_t end, bool temporary); void bootmem_setup(void); /* - * Allocate contiguous physical pages. + * Allocate memory. * - * The pages returned are guaranteed to be part of the direct physical - * mapping when paging is enabled. - * - * This function should only be used to allocate initial page table pages. - * Those pages are later loaded into the VM system (as reserved pages) - * which means they can be freed like other regular pages. Users should - * fix up the type of those pages once the VM system is initialized. + * The size of the returned region is a power-of-two, and its address is + * aligned on that size. The region is guaranteed to be part of the direct + * physical mapping when paging is enabled. * * This function is called before paging is enabled. */ void * bootmem_alloc(size_t size); +/* + * Return the end address of the direct physical mapping. + */ phys_addr_t bootmem_directmap_end(void); #endif /* _KERN_BOOTMEM_H */ |