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vmalloc.h revision 1.7 
      1 /*	$NetBSD: vmalloc.h,v 1.7 2018/08/27 14:40:56 riastradh Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 2013, 2018 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Taylor R. Campbell.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     29  * POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 
     32 #ifndef _LINUX_VMALLOC_H_
     33 #define _LINUX_VMALLOC_H_
     34 
     35 #include <sys/malloc.h>
     36 
     37 #include <uvm/uvm_extern.h>
     38 
     39 #include <linux/mm_types.h>
     40 
     41 #include <asm/page.h>
     42 
     43 /*
     44  * XXX vmalloc and kmalloc both use malloc(9).  If you change this, be
     45  * sure to update kmalloc in <linux/slab.h> and kvfree in <linux/mm.h>.
     46  */
     47 
     48 static inline bool
     49 is_vmalloc_addr(void *addr)
     50 {
     51 	return true;
     52 }
     53 
     54 static inline void *
     55 vmalloc(unsigned long size)
     56 {
     57 	return malloc(size, M_TEMP, M_WAITOK);
     58 }
     59 
     60 static inline void *
     61 vmalloc_user(unsigned long size)
     62 {
     63 	return malloc(size, M_TEMP, (M_WAITOK | M_ZERO));
     64 }
     65 
     66 static inline void *
     67 vzalloc(unsigned long size)
     68 {
     69 	return malloc(size, M_TEMP, (M_WAITOK | M_ZERO));
     70 }
     71 
     72 static inline void
     73 vfree(void *ptr)
     74 {
     75 	if (ptr == NULL)
     76 		return;
     77 	return free(ptr, M_TEMP);
     78 }
     79 
     80 #define	PAGE_KERNEL	UVM_PROT_RW
     81 
     82 /*
     83  * vmap(pages, npages, flags, prot)
     84  *
     85  *	Map pages[0], pages[1], ..., pages[npages-1] into contiguous
     86  *	kernel virtual address space with the specified protection, and
     87  *	return a KVA pointer to the start.
     88  *
     89  *	prot may be a bitwise ior of UVM_PROT_READ/WRITE/EXEC and
     90  *	PMAP_* cache flags accepted by pmap_enter().
     91  */
     92 static inline void *
     93 vmap(struct page **pages, unsigned npages, unsigned long flags,
     94     pgprot_t protflags)
     95 {
     96 	vm_prot_t justprot = protflags & UVM_PROT_ALL;
     97 	vaddr_t va;
     98 	unsigned i;
     99 
    100 	/* Allocate some KVA, or return NULL if we can't.  */
    101 	va = uvm_km_alloc(kernel_map, (vsize_t)npages << PAGE_SHIFT, PAGE_SIZE,
    102 	    UVM_KMF_VAONLY|UVM_KMF_NOWAIT);
    103 	if (va == 0)
    104 		return NULL;
    105 
    106 	/* Ask pmap to map the KVA to the specified page addresses.  */
    107 	for (i = 0; i < npages; i++) {
    108 		pmap_kenter_pa(va + i*PAGE_SIZE, page_to_phys(pages[i]),
    109 		    justprot, protflags);
    110 	}
    111 
    112 	/* Commit the pmap updates.  */
    113 	pmap_update(pmap_kernel());
    114 
    115 	return (void *)va;
    116 }
    117 
    118 /*
    119  * vunmap(ptr, npages)
    120  *
    121  *	Unmap the KVA pages starting at ptr that were mapped by a call
    122  *	to vmap with the same npages parameter.
    123  */
    124 static inline void
    125 vunmap(void *ptr, unsigned npages)
    126 {
    127 	vaddr_t va = (vaddr_t)ptr;
    128 
    129 	/* Ask pmap to unmap the KVA.  */
    130 	pmap_kremove(va, (vsize_t)npages << PAGE_SHIFT);
    131 
    132 	/* Commit the pmap updates.  */
    133 	pmap_update(pmap_kernel());
    134 
    135 	/*
    136 	 * Now that the pmap is no longer mapping the KVA we allocated
    137 	 * on any CPU, it is safe to free the KVA.
    138 	 */
    139 	uvm_km_free(kernel_map, va, (vsize_t)npages << PAGE_SHIFT,
    140 	    UVM_KMF_VAONLY);
    141 }
    142 
    143 #endif  /* _LINUX_VMALLOC_H_ */
    144