root/usr/src/uts/i86pc/sys/mach_mmu.h
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 *
 * Copyright 2018 Joyent, Inc.
 * Copyright 2022 Tintri by DDN, Inc. All rights reserved.
 */

#ifndef _SYS_MACH_MMU_H
#define _SYS_MACH_MMU_H

#ifdef __cplusplus
extern "C" {
#endif

#ifndef _ASM

#include <sys/types.h>
#include <sys/systm.h>

/*
 * Platform-dependent MMU routines and types.
 *
 * WARNING: this header file is used by both dboot and i86pc, so don't go using
 * normal kernel headers.
 */

#define TWO_MEG         (2 * 1024 * 1024)

/*
 * This is:
 *      The kernel nucleus pagesizes, ie: bi->bi_kseg_size
 *      The grub 64 bit file load address (see multiboot header in dboot_grub.s)
 *      The grub 32 bit and hypervisor physical load addresses of
 *          the kernel text/data (see Mapfile.unix)
 */
#define FOUR_MEG        (4 * 1024 * 1024)

#define ONE_GIG         (1024 * 1024 * 1024)
#define FOUR_GIG        ((uint64_t)4 * ONE_GIG)

#define MMU_STD_PAGESIZE        4096

/*
 * Defines for 4 and 5 level Virtual address ranges
 */
#define MMU_NPGOFFBITS          12
#define MMU_NPTIXBITS           9
#define MMU_MAX4LEVELVABITS     (4 * MMU_NPTIXBITS + MMU_NPGOFFBITS)
#define MMU_MAX5LEVELVABITS     (5 * MMU_NPTIXBITS + MMU_NPGOFFBITS)

#ifdef __amd64
#define MMU_STD_PAGEMASK        0xFFFFFFFFFFFFF000ULL
#else
#define MMU_STD_PAGEMASK        0xFFFFF000UL
#endif

/*
 * Defines for the bits in X86 and AMD64 Page Tables
 *
 * Notes:
 *
 * Largepages and PAT bits:
 *
 * bit 7 at level 0 is the PAT bit
 * bit 7 above level 0 is the Pagesize bit (set for large page)
 * bit 12 (when a large page) is the PAT bit
 *
 * In Solaris the PAT/PWT/PCD values are set up so that:
 *
 * PAT & PWT -> Write Protected
 * PAT & PCD -> Write Combining
 * PAT by itself (PWT == 0 && PCD == 0) yields uncacheable (same as PCD == 1)
 *
 *
 * Permission bits:
 *
 * - PT_USER must be set in all levels for user pages
 * - PT_WRITE must be set in all levels for user writable pages
 * - PT_NX applies if set at any level
 *
 * For these, we use the "allow" settings in all tables above level 0 and only
 * ever disable things in PTEs.
 *
 * The use of PT_GLOBAL and PT_NX depend on being enabled in processor
 * control registers. Hence, we use a variable to reference these bit
 * masks. During hat_kern_setup() if the feature isn't enabled we
 * clear out the variables.
 */
#define PT_VALID        (0x001) /* a valid translation is present */
#define PT_WRITABLE     (0x002) /* the page is writable */
#define PT_USER         (0x004) /* the page is accessible by user mode */
#define PT_WRITETHRU    (0x008) /* write back caching is disabled (non-PAT) */
#define PT_NOCACHE      (0x010) /* page is not cacheable (non-PAT) */
#define PT_REF          (0x020) /* page was referenced */
#define PT_MOD          (0x040) /* page was modified */
#define PT_PAGESIZE     (0x080) /* above level 0, indicates a large page */
#define PT_PAT_4K       (0x080) /* at level 0, used for write combining */
#define PT_GLOBAL       (0x100) /* the mapping is global */
#define PT_SOFTWARE     (0xe00) /* software bits */

#define PT_PAT_LARGE    (0x1000)        /* PAT bit for large pages */

#define PT_PTPBITS      (PT_VALID | PT_USER | PT_WRITABLE | PT_REF)
#define PT_FLAGBITS     (0xfff) /* for masking off flag bits */

/*
 * The software bits are used by the HAT to track attributes.
 * Note that the attributes are inclusive as the values increase.
 *
 * PT_NOSYNC - The PT_REF/PT_MOD bits are not sync'd to page_t.
 *             The hat will install them as always set.
 *
 * PT_NOCONSIST - There is no hment entry for this mapping.
 *
 * PT_FOREIGN - used for the hypervisor, check via
 *              (pte & PT_SOFTWARE) >= PT_FOREIGN
 *              as it might set 0x800 for foreign grant table mappings.
 */
#define PT_NOSYNC       (0x200) /* PTE was created with HAT_NOSYNC */
#define PT_NOCONSIST    (0x400) /* PTE was created with HAT_LOAD_NOCONSIST */
#define PT_FOREIGN      (0x600) /* MFN mapped on the hypervisor has no PFN */

#ifndef _BOOT

extern ulong_t getcr3(void);
extern void setcr3(ulong_t);

#define getcr3_pa() (getcr3() & MMU_PAGEMASK)
#define getpcid() ((getcr4() & CR4_PCIDE) ? \
        (getcr3() & MMU_PAGEOFFSET) : PCID_NONE)

extern void mmu_invlpg(caddr_t);

#endif

#ifdef __xpv
#include <sys/xen_mmu.h>
#else
#include <sys/pc_mmu.h>
#endif

/*
 * The software extraction for a single Page Table Entry will always
 * be a 64 bit unsigned int. If running a non-PAE hat, the page table
 * access routines know to extend/shorten it to 32 bits.
 */
typedef uint64_t x86pte_t;
typedef uint32_t x86pte32_t;

x86pte_t get_pteval(paddr_t, uint_t);
void set_pteval(paddr_t, uint_t, uint_t, x86pte_t);
paddr_t make_ptable(x86pte_t *, uint_t);
x86pte_t *find_pte(uint64_t, paddr_t *, uint_t, uint_t);
x86pte_t *map_pte(paddr_t, uint_t);

extern uint_t *shift_amt;
extern uint_t ptes_per_table;
extern paddr_t top_page_table;
extern uint_t top_level;
extern uint_t pte_size;
extern uint_t shift_amt_nopae[];
extern uint_t shift_amt_pae[];
extern uint32_t lpagesize;

#ifdef __cplusplus
}
#endif

#endif /* _ASM */

#endif  /* _SYS_MACH_MMU_H */