From mboxrd@z Thu Jan 1 00:00:00 1970 From: ard.biesheuvel@linaro.org (Ard Biesheuvel) Date: Mon, 1 Feb 2016 19:30:17 +0100 Subject: [PATCH] arm64: move back to generic memblock_enforce_memory_limit() In-Reply-To: <20160201180256.GJ15514@e104818-lin.cambridge.arm.com> References: <20160201180256.GJ15514@e104818-lin.cambridge.arm.com> Message-ID: <1454351417-23732-1-git-send-email-ard.biesheuvel@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Rather than implementing our own elaborate logic to clip the memory ranges in order of preference, use the generic memblock_enforce_memory_limit() as before, and explicitly add back that part of the kernel that needs to be accessible via the linear mapping as well as via the kernel mapping. Signed-off-by: Ard Biesheuvel --- arch/arm64/mm/init.c | 59 +++++++--------------------------------------------- 1 file changed, 7 insertions(+), 52 deletions(-) diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index e8e853a1024c..361c91209031 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -160,41 +160,6 @@ static int __init early_mem(char *p) } early_param("mem", early_mem); -/* - * clip_mem_range() - remove memblock memory between @min and @max until - * we meet the limit in 'memory_limit'. - */ -static void __init clip_mem_range(u64 min, u64 max) -{ - u64 mem_size, to_remove; - int i; - -again: - mem_size = memblock_phys_mem_size(); - if (mem_size <= memory_limit || max <= min) - return; - - to_remove = mem_size - memory_limit; - - for (i = memblock.memory.cnt - 1; i >= 0; i--) { - struct memblock_region *r = memblock.memory.regions + i; - u64 start = max(min, r->base); - u64 end = min(max, r->base + r->size); - - if (start >= max || end <= min) - continue; - - if (end > min) { - u64 size = min(to_remove, end - max(start, min)); - - memblock_remove(end - size, size); - } else { - memblock_remove(start, min(max - start, to_remove)); - } - goto again; - } -} - void __init arm64_memblock_init(void) { const s64 linear_region_size = -(s64)PAGE_OFFSET; @@ -215,24 +180,14 @@ void __init arm64_memblock_init(void) if (memblock_end_of_DRAM() > linear_region_size) memblock_remove(0, memblock_end_of_DRAM() - linear_region_size); + /* + * Apply the memory limit if it was set. Since the kernel may be loaded + * high up in memory, add back the kernel region that must be accessible + * via the linear mapping. + */ if (memory_limit != (phys_addr_t)ULLONG_MAX) { - u64 kbase = round_down(__pa(_text), MIN_KIMG_ALIGN); - u64 kend = PAGE_ALIGN(__pa(_end)); - u64 const sz_4g = 0x100000000UL; - - /* - * Clip memory in order of preference: - * - above the kernel and above 4 GB - * - between 4 GB and the start of the kernel (if the kernel - * is loaded high in memory) - * - between the kernel and 4 GB (if the kernel is loaded - * low in memory) - * - below 4 GB - */ - clip_mem_range(max(sz_4g, kend), ULLONG_MAX); - clip_mem_range(sz_4g, kbase); - clip_mem_range(kend, sz_4g); - clip_mem_range(0, min(kbase, sz_4g)); + memblock_enforce_memory_limit(memory_limit); + memblock_add(__pa(__init_begin), (u64)(_end - __init_begin)); } /* -- 2.5.0