/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_VMALLOC_H
#define _LINUX_VMALLOC_H

#include <linux/spinlock.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/llist.h>
#include <asm/page.h>           /* pgprot_t */
#include <linux/rbtree.h>
#include <linux/overflow.h>

#include <asm/vmalloc.h>

struct vm_area_struct;          /* vma defining user mapping in mm_types.h */
struct notifier_block;          /* in notifier.h */

/* bits in flags of vmalloc's vm_struct below */
#define VM_IOREMAP              0x00000001      /* ioremap() and friends */
#define VM_ALLOC                0x00000002      /* vmalloc() */
#define VM_MAP                  0x00000004      /* vmap()ed pages */
#define VM_USERMAP              0x00000008      /* suitable for remap_vmalloc_range */
#define VM_DMA_COHERENT         0x00000010      /* dma_alloc_coherent */
#define VM_UNINITIALIZED        0x00000020      /* vm_struct is not fully initialized */
#define VM_NO_GUARD             0x00000040      /* don't add guard page */
#define VM_KASAN                0x00000080      /* has allocated kasan shadow memory */
#define VM_FLUSH_RESET_PERMS    0x00000100      /* reset direct map and flush TLB on unmap, can't be freed in atomic context */
#define VM_MAP_PUT_PAGES        0x00000200      /* put pages and free array in vfree */
#define VM_NO_HUGE_VMAP         0x00000400      /* force PAGE_SIZE pte mapping */

/*
 * VM_KASAN is used slightly differently depending on CONFIG_KASAN_VMALLOC.
 *
 * If IS_ENABLED(CONFIG_KASAN_VMALLOC), VM_KASAN is set on a vm_struct after
 * shadow memory has been mapped. It's used to handle allocation errors so that
 * we don't try to poison shadow on free if it was never allocated.
 *
 * Otherwise, VM_KASAN is set for kasan_module_alloc() allocations and used to
 * determine which allocations need the module shadow freed.
 */

/* bits [20..32] reserved for arch specific ioremap internals */

/*
 * Maximum alignment for ioremap() regions.
 * Can be overridden by arch-specific value.
 */
#ifndef IOREMAP_MAX_ORDER
#define IOREMAP_MAX_ORDER       (7 + PAGE_SHIFT)        /* 128 pages */
#endif

struct vm_struct {
        struct vm_struct        *next;
        void                    *addr;
        unsigned long           size;
        unsigned long           flags;
        struct page             **pages;
#ifdef CONFIG_HAVE_ARCH_HUGE_VMALLOC
        unsigned int            page_order;
#endif
        unsigned int            nr_pages;
        phys_addr_t             phys_addr;
        const void              *caller;
};

struct vmap_area {
        unsigned long va_start;
        unsigned long va_end;

        struct rb_node rb_node;         /* address sorted rbtree */
        struct list_head list;          /* address sorted list */

        /*
         * The following two variables can be packed, because
         * a vmap_area object can be either:
         *    1) in "free" tree (root is vmap_area_root)
         *    2) or "busy" tree (root is free_vmap_area_root)
         */
        union {
                unsigned long subtree_max_size; /* in "free" tree */
                struct vm_struct *vm;           /* in "busy" tree */
        };
};

/* archs that select HAVE_ARCH_HUGE_VMAP should override one or more of these */
#ifndef arch_vmap_p4d_supported
static inline bool arch_vmap_p4d_supported(pgprot_t prot)
{
        return false;
}
#endif

#ifndef arch_vmap_pud_supported
static inline bool arch_vmap_pud_supported(pgprot_t prot)
{
        return false;
}
#endif

#ifndef arch_vmap_pmd_supported
static inline bool arch_vmap_pmd_supported(pgprot_t prot)
{
        return false;
}
#endif

#ifndef arch_vmap_pte_range_map_size
static inline unsigned long arch_vmap_pte_range_map_size(unsigned long addr, unsigned long end,
                                                         u64 pfn, unsigned int max_page_shift)
{
        return PAGE_SIZE;
}
#endif

#ifndef arch_vmap_pte_supported_shift
static inline int arch_vmap_pte_supported_shift(unsigned long size)
{
        return PAGE_SHIFT;
}
#endif

/*
 *      Highlevel APIs for driver use
 */
extern void vm_unmap_ram(const void *mem, unsigned int count);
extern void *vm_map_ram(struct page **pages, unsigned int count, int node);
extern void vm_unmap_aliases(void);

#ifdef CONFIG_MMU
extern void __init vmalloc_init(void);
extern unsigned long vmalloc_nr_pages(void);
#else
static inline void vmalloc_init(void)
{
}
static inline unsigned long vmalloc_nr_pages(void) { return 0; }
#endif

extern void *vmalloc(unsigned long size);
extern void *vzalloc(unsigned long size);
extern void *vmalloc_user(unsigned long size);
extern void *vmalloc_node(unsigned long size, int node);
extern void *vzalloc_node(unsigned long size, int node);
extern void *vmalloc_32(unsigned long size);
extern void *vmalloc_32_user(unsigned long size);
extern void *__vmalloc(unsigned long size, gfp_t gfp_mask);
extern void *__vmalloc_node_range(unsigned long size, unsigned long align,
                        unsigned long start, unsigned long end, gfp_t gfp_mask,
                        pgprot_t prot, unsigned long vm_flags, int node,
                        const void *caller);
void *__vmalloc_node(unsigned long size, unsigned long align, gfp_t gfp_mask,
                int node, const void *caller);
void *vmalloc_no_huge(unsigned long size);

extern void vfree(const void *addr);
extern void vfree_atomic(const void *addr);

extern void *vmap(struct page **pages, unsigned int count,
                        unsigned long flags, pgprot_t prot);
void *vmap_pfn(unsigned long *pfns, unsigned int count, pgprot_t prot);
extern void vunmap(const void *addr);

extern int remap_vmalloc_range_partial(struct vm_area_struct *vma,
                                       unsigned long uaddr, void *kaddr,
                                       unsigned long pgoff, unsigned long size);

extern int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
                                                        unsigned long pgoff);

/*
 * Architectures can set this mask to a combination of PGTBL_P?D_MODIFIED values
 * and let generic vmalloc and ioremap code know when arch_sync_kernel_mappings()
 * needs to be called.
 */
#ifndef ARCH_PAGE_TABLE_SYNC_MASK
#define ARCH_PAGE_TABLE_SYNC_MASK 0
#endif

/*
 * There is no default implementation for arch_sync_kernel_mappings(). It is
 * relied upon the compiler to optimize calls out if ARCH_PAGE_TABLE_SYNC_MASK
 * is 0.
 */
void arch_sync_kernel_mappings(unsigned long start, unsigned long end);

/*
 *      Lowlevel-APIs (not for driver use!)
 */

static inline size_t get_vm_area_size(const struct vm_struct *area)
{
        if (!(area->flags & VM_NO_GUARD))
                /* return actual size without guard page */
                return area->size - PAGE_SIZE;
        else
                return area->size;

}

extern struct vm_struct *get_vm_area(unsigned long size, unsigned long flags);
extern struct vm_struct *get_vm_area_caller(unsigned long size,
                                        unsigned long flags, const void *caller);
extern struct vm_struct *__get_vm_area_caller(unsigned long size,
                                        unsigned long flags,
                                        unsigned long start, unsigned long end,
                                        const void *caller);
void free_vm_area(struct vm_struct *area);
extern struct vm_struct *remove_vm_area(const void *addr);
extern struct vm_struct *find_vm_area(const void *addr);

static inline bool is_vm_area_hugepages(const void *addr)
{
        /*
         * This may not 100% tell if the area is mapped with > PAGE_SIZE
         * page table entries, if for some reason the architecture indicates
         * larger sizes are available but decides not to use them, nothing
         * prevents that. This only indicates the size of the physical page
         * allocated in the vmalloc layer.
         */
#ifdef CONFIG_HAVE_ARCH_HUGE_VMALLOC
        return find_vm_area(addr)->page_order > 0;
#else
        return false;
#endif
}

#ifdef CONFIG_MMU
void vunmap_range(unsigned long addr, unsigned long end);
static inline void set_vm_flush_reset_perms(void *addr)
{
        struct vm_struct *vm = find_vm_area(addr);

        if (vm)
                vm->flags |= VM_FLUSH_RESET_PERMS;
}

#else
static inline void set_vm_flush_reset_perms(void *addr)
{
}
#endif

/* for /proc/kcore */
extern long vread(char *buf, char *addr, unsigned long count);

/*
 *      Internals.  Don't use..
 */
extern struct list_head vmap_area_list;
extern __init void vm_area_add_early(struct vm_struct *vm);
extern __init void vm_area_register_early(struct vm_struct *vm, size_t align);

#ifdef CONFIG_SMP
# ifdef CONFIG_MMU
struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
                                     const size_t *sizes, int nr_vms,
                                     size_t align);

void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms);
# else
static inline struct vm_struct **
pcpu_get_vm_areas(const unsigned long *offsets,
                const size_t *sizes, int nr_vms,
                size_t align)
{
        return NULL;
}

static inline void
pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms)
{
}
# endif
#endif

#ifdef CONFIG_MMU
#define VMALLOC_TOTAL (VMALLOC_END - VMALLOC_START)
#else
#define VMALLOC_TOTAL 0UL
#endif

int register_vmap_purge_notifier(struct notifier_block *nb);
int unregister_vmap_purge_notifier(struct notifier_block *nb);

#if defined(CONFIG_MMU) && defined(CONFIG_PRINTK)
bool vmalloc_dump_obj(void *object);
#else
static inline bool vmalloc_dump_obj(void *object) { return false; }
#endif

#endif /* _LINUX_VMALLOC_H */