[PATCH v3 13/45] powerpc/ptdump: Handle hugepd at PGD level
From: Christophe Leroy <hidden>
Date: 2020-05-11 11:25:46
Also in:
lkml
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Michael Ellerman, Linus Torvalds
The 8xx is about to map kernel linear space and IMMR using huge pages. In order to display those pages properly, ptdump needs to handle hugepd tables at PGD level. For the time being do it only at PGD level. Further patches may add handling of hugepd tables at lower level for other platforms when needed in the future. Signed-off-by: Christophe Leroy <redacted> --- v3: notepage() now takes page size instead of page shift --- arch/powerpc/mm/ptdump/ptdump.c | 29 ++++++++++++++++++++++++++--- 1 file changed, 26 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/mm/ptdump/ptdump.c b/arch/powerpc/mm/ptdump/ptdump.c
index 98d82dcf6f0b..5fc880e30175 100644
--- a/arch/powerpc/mm/ptdump/ptdump.c
+++ b/arch/powerpc/mm/ptdump/ptdump.c@@ -23,6 +23,7 @@ #include <linux/const.h> #include <asm/page.h> #include <asm/pgalloc.h> +#include <asm/hugetlb.h> #include <mm/mmu_decl.h>
@@ -269,6 +270,26 @@ static void walk_pte(struct pg_state *st, pmd_t *pmd, unsigned long start) } } +static void walk_hugepd(struct pg_state *st, hugepd_t *phpd, unsigned long start, + int pdshift, int level) +{ +#ifdef CONFIG_ARCH_HAS_HUGEPD + unsigned int i; + int shift = hugepd_shift(*phpd); + int ptrs_per_hpd = pdshift - shift > 0 ? 1 << (pdshift - shift) : 1; + + if (start & ((1 << shift) - 1)) + return; + + for (i = 0; i < ptrs_per_hpd; i++) { + unsigned long addr = start + (i << shift); + pte_t *pte = hugepte_offset(*phpd, addr, pdshift); + + note_page(st, addr, level + 1, pte_val(*pte), 1 << shift); + } +#endif +} + static void walk_pmd(struct pg_state *st, pud_t *pud, unsigned long start) { pmd_t *pmd = pmd_offset(pud, 0);
@@ -312,11 +333,13 @@ static void walk_pagetables(struct pg_state *st) * the hash pagetable. */ for (i = pgd_index(addr); i < PTRS_PER_PGD; i++, pgd++, addr += PGDIR_SIZE) { - if (!pgd_none(*pgd) && !pgd_is_leaf(*pgd)) + if (pgd_none(*pgd) || pgd_is_leaf(*pgd)) + note_page(st, addr, 1, pgd_val(*pgd), PGDIR_SIZE); + else if (is_hugepd(__hugepd(pgd_val(*pgd)))) + walk_hugepd(st, (hugepd_t *)pgd, addr, PGDIR_SHIFT, 1); + else /* pgd exists */ walk_pud(st, pgd, addr); - else - note_page(st, addr, 1, pgd_val(*pgd), PGDIR_SIZE); } }
--
2.25.0