From e63075a3c9377536d085bc013cd3fe6323162449 Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Tue, 6 Jul 2010 15:39:01 -0700 Subject: memblock: Introduce default allocation limit and use it to replace explicit ones This introduce memblock.current_limit which is used to limit allocations from memblock_alloc() or memblock_alloc_base(..., MEMBLOCK_ALLOC_ACCESSIBLE). The old MEMBLOCK_ALLOC_ANYWHERE changes value from 0 to ~(u64)0 and can still be used with memblock_alloc_base() to allocate really anywhere. It is -no-longer- cropped to MEMBLOCK_REAL_LIMIT which disappears. Note to archs: I'm leaving the default limit to MEMBLOCK_ALLOC_ANYWHERE. I strongly recommend that you ensure that you set an appropriate limit during boot in order to guarantee that an memblock_alloc() at any time results in something that is accessible with a simple __va(). The reason is that a subsequent patch will introduce the ability for the array to resize itself by reallocating itself. The MEMBLOCK core will honor the current limit when performing those allocations. Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/mm/init_32.c | 29 +++++++---------------------- 1 file changed, 7 insertions(+), 22 deletions(-) (limited to 'arch/powerpc/mm/init_32.c') diff --git a/arch/powerpc/mm/init_32.c b/arch/powerpc/mm/init_32.c index 6a6975dc2654..59b208b7ec6f 100644 --- a/arch/powerpc/mm/init_32.c +++ b/arch/powerpc/mm/init_32.c @@ -91,12 +91,6 @@ int __allow_ioremap_reserved; /* max amount of low RAM to map in */ unsigned long __max_low_memory = MAX_LOW_MEM; -/* - * address of the limit of what is accessible with initial MMU setup - - * 256MB usually, but only 16MB on 601. - */ -phys_addr_t __initial_memory_limit_addr = (phys_addr_t)0x10000000; - /* * Check for command-line options that affect what MMU_init will do. */ @@ -126,13 +120,6 @@ void __init MMU_init(void) if (ppc_md.progress) ppc_md.progress("MMU:enter", 0x111); - /* 601 can only access 16MB at the moment */ - if (PVR_VER(mfspr(SPRN_PVR)) == 1) - __initial_memory_limit_addr = 0x01000000; - /* 8xx can only access 8MB at the moment */ - if (PVR_VER(mfspr(SPRN_PVR)) == 0x50) - __initial_memory_limit_addr = 0x00800000; - /* parse args from command line */ MMU_setup(); @@ -190,20 +177,18 @@ void __init MMU_init(void) #ifdef CONFIG_BOOTX_TEXT btext_unmap(); #endif + + /* Shortly after that, the entire linear mapping will be available */ + memblock_set_current_limit(lowmem_end_addr); } /* This is only called until mem_init is done. */ void __init *early_get_page(void) { - void *p; - - if (init_bootmem_done) { - p = alloc_bootmem_pages(PAGE_SIZE); - } else { - p = __va(memblock_alloc_base(PAGE_SIZE, PAGE_SIZE, - __initial_memory_limit_addr)); - } - return p; + if (init_bootmem_done) + return alloc_bootmem_pages(PAGE_SIZE); + else + return __va(memblock_alloc(PAGE_SIZE, PAGE_SIZE)); } /* Free up now-unused memory */ -- cgit v1.2.3-59-g8ed1b