All hugetlb range freeing functions have a verification like the following,
which only differs by the mask used, depending on the page table level.
start &= MASK;
if (start < floor)
return;
if (ceiling) {
ceiling &= MASK;
if (! ceiling)
return;
}
if (end - 1 > ceiling - 1)
return;
Refactor that into a helper function which takes the mask as
an argument, returning true when [start;end[ is not fully
contained inside [floor;ceiling[
Signed-off-by: Christophe Leroy <christophe.le...@csgroup.eu>
---
arch/powerpc/mm/hugetlbpage.c | 56 ++++++++++++-----------------------
1 file changed, 19 insertions(+), 37 deletions(-)
diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index 36c3800769fb..f8d8a4988e15 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -294,6 +294,21 @@ static void hugepd_free(struct mmu_gather *tlb, void
*hugepte)
static inline void hugepd_free(struct mmu_gather *tlb, void *hugepte) {}
#endif
+/* Return true when the entry to be freed maps more than the area being freed
*/
+static bool range_is_outside_limits(unsigned long start, unsigned long end,
+ unsigned long floor, unsigned long ceiling,
+ unsigned long mask)
+{
+ if ((start & mask) < floor)
+ return true;
+ if (ceiling) {
+ ceiling &= mask;
+ if (!ceiling)
+ return true;
+ }
+ return end - 1 > ceiling - 1;
+}
+
static void free_hugepd_range(struct mmu_gather *tlb, hugepd_t *hpdp, int
pdshift,
unsigned long start, unsigned long end,
unsigned long floor, unsigned long ceiling)
@@ -309,15 +324,7 @@ static void free_hugepd_range(struct mmu_gather *tlb,
hugepd_t *hpdp, int pdshif
if (shift > pdshift)
num_hugepd = 1 << (shift - pdshift);
- start &= pdmask;
- if (start < floor)
- return;
- if (ceiling) {
- ceiling &= pdmask;
- if (! ceiling)
- return;
- }
- if (end - 1 > ceiling - 1)
+ if (range_is_outside_limits(start, end, floor, ceiling, pdmask))
return;
for (i = 0; i < num_hugepd; i++, hpdp++)
@@ -334,18 +341,9 @@ static void hugetlb_free_pte_range(struct mmu_gather *tlb,
pmd_t *pmd,
unsigned long addr, unsigned long end,
unsigned long floor, unsigned long ceiling)
{
- unsigned long start = addr;
pgtable_t token = pmd_pgtable(*pmd);
- start &= PMD_MASK;
- if (start < floor)
- return;
- if (ceiling) {
- ceiling &= PMD_MASK;
- if (!ceiling)
- return;
- }
- if (end - 1 > ceiling - 1)
+ if (range_is_outside_limits(addr, end, floor, ceiling, PMD_MASK))
return;
pmd_clear(pmd);
@@ -395,15 +393,7 @@ static void hugetlb_free_pmd_range(struct mmu_gather *tlb,
pud_t *pud,
addr, next, floor, ceiling);
} while (addr = next, addr != end);
- start &= PUD_MASK;
- if (start < floor)
- return;
- if (ceiling) {
- ceiling &= PUD_MASK;
- if (!ceiling)
- return;
- }
- if (end - 1 > ceiling - 1)
+ if (range_is_outside_limits(start, end, floor, ceiling, PUD_MASK))
return;
pmd = pmd_offset(pud, start);
@@ -446,15 +436,7 @@ static void hugetlb_free_pud_range(struct mmu_gather *tlb,
p4d_t *p4d,
}
} while (addr = next, addr != end);
- start &= PGDIR_MASK;
- if (start < floor)
- return;
- if (ceiling) {
- ceiling &= PGDIR_MASK;
- if (!ceiling)
- return;
- }
- if (end - 1 > ceiling - 1)
+ if (range_is_outside_limits(start, end, floor, ceiling, PGDIR_MASK))
return;
pud = pud_offset(p4d, start);
--
2.25.0
