From b6f1f0dea1469e0c956eb89399916d60dd2a3808 Mon Sep 17 00:00:00 2001 From: Franck Bui-Huu Date: Fri, 11 Aug 2006 17:51:48 +0200 Subject: [PATCH] [MIPS] setup.c: cleanup bootmem_init() This function although doing simple thing is hard to follow. It's mainly due to: - a lot of #ifdef - bad local names - redundant tests So this patch try to address these issues. It also do not use max_pfn global which is marked as an unused exported symbol. As a bonus side, it's now really easy to see what part of the code is for no-numa system. There's also no point to make this function inline. Signed-off-by: Franck Bui-Huu Signed-off-by: Ralf Baechle --- arch/mips/kernel/setup.c | 135 ++++++++++++++++++++--------------------------- 1 file changed, 57 insertions(+), 78 deletions(-) diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c index 8c2b596..bcbd926 100644 --- a/arch/mips/kernel/setup.c +++ b/arch/mips/kernel/setup.c @@ -96,6 +96,12 @@ void __init add_memory_region(phys_t start, phys_t size, long type) int x = boot_mem_map.nr_map; struct boot_mem_map_entry *prev = boot_mem_map.map + x - 1; + /* Sanity check */ + if (start + size < start) { + printk("Trying to add an invalid memory region, skipped\n"); + return; + } + /* * Try to merge with previous entry if any. This is far less than * perfect but is sufficient for most real world cases. @@ -257,15 +263,16 @@ static inline int parse_rd_cmdline(unsigned long* rd_start, unsigned long* rd_en return 0; } -#define MAXMEM HIGHMEM_START -#define MAXMEM_PFN PFN_DOWN(MAXMEM) - -static inline void bootmem_init(void) +/* + * Initialize the bootmem allocator. It also setup initrd related data + * if needed. + */ +static void __init bootmem_init(void) { - unsigned long start_pfn; unsigned long reserved_end = (unsigned long)&_end; #ifndef CONFIG_SGI_IP27 - unsigned long first_usable_pfn; + unsigned long highest = 0; + unsigned long mapstart = -1UL; unsigned long bootmap_size; int i; #endif @@ -281,7 +288,7 @@ static inline void bootmem_init(void) unsigned long tmp; u32 *initrd_header; - tmp = ((reserved_end + PAGE_SIZE-1) & PAGE_MASK) - sizeof(u32) * 2; + tmp = PAGE_ALIGN(reserved_end) - sizeof(u32) * 2; if (tmp < reserved_end) tmp += PAGE_SIZE; initrd_header = (u32 *)tmp; @@ -294,16 +301,15 @@ static inline void bootmem_init(void) } #endif /* CONFIG_BLK_DEV_INITRD */ +#ifndef CONFIG_SGI_IP27 /* - * Partially used pages are not usable - thus - * we are rounding upwards. + * reserved_end is now a pfn */ - start_pfn = PFN_UP(CPHYSADDR(reserved_end)); + reserved_end = PFN_UP(CPHYSADDR(reserved_end)); -#ifndef CONFIG_SGI_IP27 - /* Find the highest page frame number we have available. */ - max_pfn = 0; - first_usable_pfn = -1UL; + /* + * Find the highest page frame number we have available. + */ for (i = 0; i < boot_mem_map.nr_map; i++) { unsigned long start, end; @@ -312,56 +318,38 @@ static inline void bootmem_init(void) start = PFN_UP(boot_mem_map.map[i].addr); end = PFN_DOWN(boot_mem_map.map[i].addr - + boot_mem_map.map[i].size); + + boot_mem_map.map[i].size); - if (start >= end) + if (end > highest) + highest = end; + if (end <= reserved_end) continue; - if (end > max_pfn) - max_pfn = end; - if (start < first_usable_pfn) { - if (start > start_pfn) { - first_usable_pfn = start; - } else if (end > start_pfn) { - first_usable_pfn = start_pfn; - } - } + if (start >= mapstart) + continue; + mapstart = max(reserved_end, start); } /* * Determine low and high memory ranges */ - max_low_pfn = max_pfn; - if (max_low_pfn > MAXMEM_PFN) { - max_low_pfn = MAXMEM_PFN; -#ifndef CONFIG_HIGHMEM - /* Maximum memory usable is what is directly addressable */ - printk(KERN_WARNING "Warning only %ldMB will be used.\n", - MAXMEM >> 20); - printk(KERN_WARNING "Use a HIGHMEM enabled kernel.\n"); + if (highest > PFN_DOWN(HIGHMEM_START)) { +#ifdef CONFIG_HIGHMEM + highstart_pfn = PFN_DOWN(HIGHMEM_START); + highend_pfn = highest; #endif + highest = PFN_DOWN(HIGHMEM_START); } -#ifdef CONFIG_HIGHMEM /* - * Crude, we really should make a better attempt at detecting - * highstart_pfn + * Initialize the boot-time allocator with low memory only. */ - highstart_pfn = highend_pfn = max_pfn; - if (max_pfn > MAXMEM_PFN) { - highstart_pfn = MAXMEM_PFN; - printk(KERN_NOTICE "%ldMB HIGHMEM available.\n", - (highend_pfn - highstart_pfn) >> (20 - PAGE_SHIFT)); - } -#endif - - /* Initialize the boot-time allocator with low memory only. */ - bootmap_size = init_bootmem(first_usable_pfn, max_low_pfn); + bootmap_size = init_bootmem(mapstart, highest); /* * Register fully available low RAM pages with the bootmem allocator. */ for (i = 0; i < boot_mem_map.nr_map; i++) { - unsigned long curr_pfn, last_pfn, size; + unsigned long start, end, size; /* * Reserve usable memory. @@ -369,49 +357,37 @@ static inline void bootmem_init(void) if (boot_mem_map.map[i].type != BOOT_MEM_RAM) continue; - /* - * We are rounding up the start address of usable memory: - */ - curr_pfn = PFN_UP(boot_mem_map.map[i].addr); - if (curr_pfn >= max_low_pfn) - continue; - if (curr_pfn < start_pfn) - curr_pfn = start_pfn; - - /* - * ... and at the end of the usable range downwards: - */ - last_pfn = PFN_DOWN(boot_mem_map.map[i].addr + start = PFN_UP(boot_mem_map.map[i].addr); + end = PFN_DOWN(boot_mem_map.map[i].addr + boot_mem_map.map[i].size); - - if (last_pfn > max_low_pfn) - last_pfn = max_low_pfn; - /* - * Only register lowmem part of lowmem segment with bootmem. + * We are rounding up the start address of usable memory + * and at the end of the usable range downwards. */ - size = last_pfn - curr_pfn; - if (curr_pfn > PFN_DOWN(HIGHMEM_START)) - continue; - if (curr_pfn + size - 1 > PFN_DOWN(HIGHMEM_START)) - size = PFN_DOWN(HIGHMEM_START) - curr_pfn; - if (!size) + if (start >= max_low_pfn) continue; + if (start < reserved_end) + start = reserved_end; + if (end > max_low_pfn) + end = max_low_pfn; /* - * ... finally, did all the rounding and playing - * around just make the area go away? + * ... finally, is the area going away? */ - if (last_pfn <= curr_pfn) + if (end <= start) continue; + size = end - start; /* Register lowmem ranges */ - free_bootmem(PFN_PHYS(curr_pfn), PFN_PHYS(size)); - memory_present(0, curr_pfn, curr_pfn + size - 1); + free_bootmem(PFN_PHYS(start), size << PAGE_SHIFT); + memory_present(0, start, end); } - /* Reserve the bootmap memory. */ - reserve_bootmem(PFN_PHYS(first_usable_pfn), bootmap_size); + /* + * Reserve the bootmap memory. + */ + reserve_bootmem(PFN_PHYS(mapstart), bootmap_size); + #endif /* CONFIG_SGI_IP27 */ #ifdef CONFIG_BLK_DEV_INITRD @@ -483,6 +459,9 @@ static void __init arch_mem_init(char **cmdline_p) paging_init(); } +#define MAXMEM HIGHMEM_START +#define MAXMEM_PFN PFN_DOWN(MAXMEM) + static inline void resource_init(void) { int i; -- 2.7.4