From 69e26be9b1d0c83d3581475095ce2a1ccc578215 Mon Sep 17 00:00:00 2001 From: Andreas Herrmann Date: Fri, 20 Jun 2008 22:03:06 +0200 Subject: [PATCH] x86: pat.c more trivial changes - add BUG statement to catch invalid start and end parameters - No need to track the actual type in both req_type and actual_type -- keep req_type unchanged. - removed (IMHO) superfluous comments Signed-off-by: Andreas Herrmann Cc: Venkatesh Pallipadi Cc: Suresh B Siddha Signed-off-by: Ingo Molnar --- arch/x86/mm/pat.c | 21 ++++++++------------- 1 file changed, 8 insertions(+), 13 deletions(-) diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c index a6507bfb12a..c996a364120 100644 --- a/arch/x86/mm/pat.c +++ b/arch/x86/mm/pat.c @@ -200,7 +200,8 @@ int reserve_memtype(u64 start, u64 end, unsigned long req_type, unsigned long actual_type; int err = 0; - /* Only track when pat_enabled */ + BUG_ON(start >= end); /* end is exclusive */ + if (!pat_enabled) { /* This is identical to page table setting without PAT */ if (new_type) { @@ -228,17 +229,13 @@ int reserve_memtype(u64 start, u64 end, unsigned long req_type, */ u8 mtrr_type = mtrr_type_lookup(start, end); - if (mtrr_type == MTRR_TYPE_WRBACK) { - req_type = _PAGE_CACHE_WB; + if (mtrr_type == MTRR_TYPE_WRBACK) actual_type = _PAGE_CACHE_WB; - } else { - req_type = _PAGE_CACHE_UC_MINUS; + else actual_type = _PAGE_CACHE_UC_MINUS; - } - } else { - req_type &= _PAGE_CACHE_MASK; - actual_type = pat_x_mtrr_type(start, end, req_type); - } + } else + actual_type = pat_x_mtrr_type(start, end, + req_type & _PAGE_CACHE_MASK); new = kmalloc(sizeof(struct memtype), GFP_KERNEL); if (!new) @@ -406,10 +403,8 @@ int free_memtype(u64 start, u64 end) struct memtype *entry; int err = -EINVAL; - /* Only track when pat_enabled */ - if (!pat_enabled) { + if (!pat_enabled) return 0; - } /* Low ISA region is always mapped WB. No need to track */ if (is_ISA_range(start, end - 1)) -- 2.41.1