diff options
| author | Kevin Brodsky <kevin.brodsky@arm.com> | 2025-01-03 18:44:14 +0000 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2025-01-25 20:22:24 -0800 |
| commit | a9b3c355c2e6388b0a3b67627460a516d88bdbc9 (patch) | |
| tree | 0d71f36a7390cafa3c073d239537b6ae439135de /arch/arm/mm | |
| parent | ARM: mm: rename PGD helpers (diff) | |
| download | linux-a9b3c355c2e6388b0a3b67627460a516d88bdbc9.tar.gz linux-a9b3c355c2e6388b0a3b67627460a516d88bdbc9.zip | |
asm-generic: pgalloc: provide generic __pgd_{alloc,free}
We already have a generic implementation of alloc/free up to P4D level, as
well as pgd_free(). Let's finish the work and add a generic PGD-level
alloc helper as well.
Unlike at lower levels, almost all architectures need some specific magic
at PGD level (typically initialising PGD entries), so introducing a
generic pgd_alloc() isn't worth it. Instead we introduce two new helpers,
__pgd_alloc() and __pgd_free(), and make use of them in the arch-specific
pgd_alloc() and pgd_free() wherever possible. To accommodate as many arch
as possible, __pgd_alloc() takes a page allocation order.
Because pagetable_alloc() allocates zeroed pages, explicit zeroing in
pgd_alloc() becomes redundant and we can get rid of it. Some trivial
implementations of pgd_free() also become unnecessary once __pgd_alloc()
is used; remove them.
Another small improvement is consistent accounting of PGD pages by using
GFP_PGTABLE_{USER,KERNEL} as appropriate.
Not all PGD allocations can be handled by the generic helpers. In
particular, multiple architectures allocate PGDs from a kmem_cache, and
those PGDs may not be page-sized.
Link: https://lkml.kernel.org/r/20250103184415.2744423-6-kevin.brodsky@arm.com
Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'arch/arm/mm')
| -rw-r--r-- | arch/arm/mm/pgd.c | 8 |
1 files changed, 3 insertions, 5 deletions
diff --git a/arch/arm/mm/pgd.c b/arch/arm/mm/pgd.c index 2a1077747758..4eb81b7ed03a 100644 --- a/arch/arm/mm/pgd.c +++ b/arch/arm/mm/pgd.c @@ -17,11 +17,11 @@ #include "mm.h" #ifdef CONFIG_ARM_LPAE -#define _pgd_alloc(mm) kmalloc_array(PTRS_PER_PGD, sizeof(pgd_t), GFP_KERNEL) +#define _pgd_alloc(mm) kmalloc_array(PTRS_PER_PGD, sizeof(pgd_t), GFP_KERNEL | __GFP_ZERO) #define _pgd_free(mm, pgd) kfree(pgd) #else -#define _pgd_alloc(mm) (pgd_t *)__get_free_pages(GFP_KERNEL, 2) -#define _pgd_free(mm, pgd) free_pages((unsigned long)pgd, 2) +#define _pgd_alloc(mm) __pgd_alloc(mm, 2) +#define _pgd_free(mm, pgd) __pgd_free(mm, pgd) #endif /* @@ -39,8 +39,6 @@ pgd_t *pgd_alloc(struct mm_struct *mm) if (!new_pgd) goto no_pgd; - memset(new_pgd, 0, USER_PTRS_PER_PGD * sizeof(pgd_t)); - /* * Copy over the kernel and IO PGD entries */ |