s390/mm: change swap pte encoding and pgtable cleanup
After the file ptes have been removed the bit combination used to
encode non-linear mappings can be reused for the swap ptes. This
frees up a precious pte software bit. Reflect the change in the
swap encoding in the comments and do some cleanup while we are
at it.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/mm/hugetlbpage.c b/arch/s390/mm/hugetlbpage.c
index c67e8bf..e617e74 100644
--- a/arch/s390/mm/hugetlbpage.c
+++ b/arch/s390/mm/hugetlbpage.c
@@ -14,20 +14,23 @@
/*
* Convert encoding pte bits pmd bits
- * .IR...wrdytp dy..R...I...wr
- * empty .10...000000 -> 00..0...1...00
- * prot-none, clean, old .11...000001 -> 00..1...1...00
- * prot-none, clean, young .11...000101 -> 01..1...1...00
- * prot-none, dirty, old .10...001001 -> 10..1...1...00
- * prot-none, dirty, young .10...001101 -> 11..1...1...00
- * read-only, clean, old .11...010001 -> 00..1...1...01
- * read-only, clean, young .01...010101 -> 01..1...0...01
- * read-only, dirty, old .11...011001 -> 10..1...1...01
- * read-only, dirty, young .01...011101 -> 11..1...0...01
- * read-write, clean, old .11...110001 -> 00..0...1...11
- * read-write, clean, young .01...110101 -> 01..0...0...11
- * read-write, dirty, old .10...111001 -> 10..0...1...11
- * read-write, dirty, young .00...111101 -> 11..0...0...11
+ * lIR.uswrdy.p dy..R...I...wr
+ * empty 010.000000.0 -> 00..0...1...00
+ * prot-none, clean, old 111.000000.1 -> 00..1...1...00
+ * prot-none, clean, young 111.000001.1 -> 01..1...1...00
+ * prot-none, dirty, old 111.000010.1 -> 10..1...1...00
+ * prot-none, dirty, young 111.000011.1 -> 11..1...1...00
+ * read-only, clean, old 111.000100.1 -> 00..1...1...01
+ * read-only, clean, young 101.000101.1 -> 01..1...0...01
+ * read-only, dirty, old 111.000110.1 -> 10..1...1...01
+ * read-only, dirty, young 101.000111.1 -> 11..1...0...01
+ * read-write, clean, old 111.001100.1 -> 00..1...1...11
+ * read-write, clean, young 101.001101.1 -> 01..1...0...11
+ * read-write, dirty, old 110.001110.1 -> 10..0...1...11
+ * read-write, dirty, young 100.001111.1 -> 11..0...0...11
+ * HW-bits: R read-only, I invalid
+ * SW-bits: p present, y young, d dirty, r read, w write, s special,
+ * u unused, l large
*/
if (pte_present(pte)) {
pmd_val(pmd) = pte_val(pte) & PAGE_MASK;
@@ -48,20 +51,23 @@
/*
* Convert encoding pmd bits pte bits
- * dy..R...I...wr .IR...wrdytp
- * empty 00..0...1...00 -> .10...001100
- * prot-none, clean, old 00..0...1...00 -> .10...000001
- * prot-none, clean, young 01..0...1...00 -> .10...000101
- * prot-none, dirty, old 10..0...1...00 -> .10...001001
- * prot-none, dirty, young 11..0...1...00 -> .10...001101
- * read-only, clean, old 00..1...1...01 -> .11...010001
- * read-only, clean, young 01..1...1...01 -> .11...010101
- * read-only, dirty, old 10..1...1...01 -> .11...011001
- * read-only, dirty, young 11..1...1...01 -> .11...011101
- * read-write, clean, old 00..0...1...11 -> .10...110001
- * read-write, clean, young 01..0...1...11 -> .10...110101
- * read-write, dirty, old 10..0...1...11 -> .10...111001
- * read-write, dirty, young 11..0...1...11 -> .10...111101
+ * dy..R...I...wr lIR.uswrdy.p
+ * empty 00..0...1...00 -> 010.000000.0
+ * prot-none, clean, old 00..1...1...00 -> 111.000000.1
+ * prot-none, clean, young 01..1...1...00 -> 111.000001.1
+ * prot-none, dirty, old 10..1...1...00 -> 111.000010.1
+ * prot-none, dirty, young 11..1...1...00 -> 111.000011.1
+ * read-only, clean, old 00..1...1...01 -> 111.000100.1
+ * read-only, clean, young 01..1...0...01 -> 101.000101.1
+ * read-only, dirty, old 10..1...1...01 -> 111.000110.1
+ * read-only, dirty, young 11..1...0...01 -> 101.000111.1
+ * read-write, clean, old 00..1...1...11 -> 111.001100.1
+ * read-write, clean, young 01..1...0...11 -> 101.001101.1
+ * read-write, dirty, old 10..0...1...11 -> 110.001110.1
+ * read-write, dirty, young 11..0...0...11 -> 100.001111.1
+ * HW-bits: R read-only, I invalid
+ * SW-bits: p present, y young, d dirty, r read, w write, s special,
+ * u unused, l large
*/
if (pmd_present(pmd)) {
pte_val(pte) = pmd_val(pmd) & _SEGMENT_ENTRY_ORIGIN_LARGE;