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linux/include/asm-generic/pgtable-nopmd.h
Peter Xu c087a5c324 mm: recover pud_leaf() definitions in nopmd case
This reverts one change in commit 924bd6a8c9 ("mm/x86: drop two
unnecessary pud_leaf() definitions").

One issue with that is it broke nopmd builds for at least both arm64 and
riscv (CONFIG_PGTABLE_LEVELS=2).  The other issue is it was overlooked that
it's a common change rather than x86 specific (relevant to the commit
message of the commit).

Normally there's no need for empty definition of pXd_leaf() because of the
fallback functions, however this logic may not apply to pgtable-nopmd.h,
because that's a header that can even be used by arch *pgtable.h headers,
which can use the *_leaf() definitions _before_ the fallback functions are
defined.  Leave it there to pass PGTABLE_LEVELS=2 builds.

Link: https://lkml.kernel.org/r/Ze8vFNV9YSdgC2S7@x1n
Fixes: 924bd6a8c9 ("mm/x86: drop two unnecessary pud_leaf() definitions")
Signed-off-by: Peter Xu <peterx@redhat.com>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202403090900.OwPqmRuI-lkp@intel.com/
Closes: https://lore.kernel.org/oe-kbuild-all/202403101607.a42gaLOS-lkp@intel.com/
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-03-13 12:12:21 -07:00

74 lines
2.0 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _PGTABLE_NOPMD_H
#define _PGTABLE_NOPMD_H
#ifndef __ASSEMBLY__
#include <asm-generic/pgtable-nopud.h>
struct mm_struct;
#define __PAGETABLE_PMD_FOLDED 1
/*
* Having the pmd type consist of a pud gets the size right, and allows
* us to conceptually access the pud entry that this pmd is folded into
* without casting.
*/
typedef struct { pud_t pud; } pmd_t;
#define PMD_SHIFT PUD_SHIFT
#define PTRS_PER_PMD 1
#define PMD_SIZE (1UL << PMD_SHIFT)
#define PMD_MASK (~(PMD_SIZE-1))
/*
* The "pud_xxx()" functions here are trivial for a folded two-level
* setup: the pmd is never bad, and a pmd always exists (as it's folded
* into the pud entry)
*/
static inline int pud_none(pud_t pud) { return 0; }
static inline int pud_bad(pud_t pud) { return 0; }
static inline int pud_present(pud_t pud) { return 1; }
static inline int pud_user(pud_t pud) { return 0; }
static inline int pud_leaf(pud_t pud) { return 0; }
static inline void pud_clear(pud_t *pud) { }
#define pmd_ERROR(pmd) (pud_ERROR((pmd).pud))
#define pud_populate(mm, pmd, pte) do { } while (0)
/*
* (pmds are folded into puds so this doesn't get actually called,
* but the define is needed for a generic inline function.)
*/
#define set_pud(pudptr, pudval) set_pmd((pmd_t *)(pudptr), (pmd_t) { pudval })
static inline pmd_t * pmd_offset(pud_t * pud, unsigned long address)
{
return (pmd_t *)pud;
}
#define pmd_offset pmd_offset
#define pmd_val(x) (pud_val((x).pud))
#define __pmd(x) ((pmd_t) { __pud(x) } )
#define pud_page(pud) (pmd_page((pmd_t){ pud }))
#define pud_pgtable(pud) ((pmd_t *)(pmd_page_vaddr((pmd_t){ pud })))
/*
* allocating and freeing a pmd is trivial: the 1-entry pmd is
* inside the pud, so has no extra memory associated with it.
*/
#define pmd_alloc_one(mm, address) NULL
static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
{
}
#define pmd_free_tlb(tlb, x, a) do { } while (0)
#undef pmd_addr_end
#define pmd_addr_end(addr, end) (end)
#endif /* __ASSEMBLY__ */
#endif /* _PGTABLE_NOPMD_H */