1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #include <sys/types.h> 27 #include <sys/errno.h> 28 #include <sys/mman.h> 29 #include <sys/cred.h> 30 #include <sys/model.h> 31 #include <sys/vnode.h> 32 #include <sys/systm.h> 33 #include <sys/kmem.h> 34 #include <sys/file.h> 35 #include <sys/vfs.h> 36 #include <sys/sysmacros.h> 37 #include <sys/mmapobj.h> 38 39 /* 40 * We will "allocate" this many mmapobj_result_t segments on the stack 41 * in an attempt to avoid the need to call kmem_alloc. This value should 42 * cover 99% of the known ELF libraries as well as AOUT (4.x) libraries. 43 */ 44 #define MOBJ_STACK_SEGS 6 45 46 static void 47 mmapobj_copy_64to32(mmapobj_result_t *source, mmapobj_result32_t *dest, int num) 48 { 49 int i; 50 51 for (i = 0; i < num; i++) { 52 dest[i].mr_addr = (caddr32_t)(uintptr_t)source[i].mr_addr; 53 dest[i].mr_msize = (size32_t)source[i].mr_msize; 54 dest[i].mr_fsize = (size32_t)source[i].mr_fsize; 55 dest[i].mr_offset = (size32_t)source[i].mr_offset; 56 dest[i].mr_prot = source[i].mr_prot; 57 dest[i].mr_flags = source[i].mr_flags; 58 } 59 } 60 61 int 62 mmapobjsys(int fd, uint_t flags, mmapobj_result_t *storage, 63 uint_t *elements, void *arg) 64 { 65 uint_t num_mapped; 66 uint_t num_in; 67 int error; 68 int old_error; 69 size_t padding = 0; 70 mmapobj_result_t stack_mr[MOBJ_STACK_SEGS]; 71 mmapobj_result_t *mrp = stack_mr; 72 struct file *fp; 73 struct vnode *vp; 74 model_t model; 75 int convert_64to32 = 0; 76 uint_t alloc_num = 0; 77 78 79 /* Verify flags */ 80 if ((flags & ~MMOBJ_ALL_FLAGS) != 0) { 81 return (set_errno(EINVAL)); 82 } 83 84 if (((flags & MMOBJ_PADDING) == 0) && arg != NULL) { 85 return (set_errno(EINVAL)); 86 } 87 88 fp = getf(fd); 89 if (fp == NULL) { 90 return (set_errno(EBADF)); 91 } 92 vp = fp->f_vnode; 93 94 if ((fp->f_flag & FREAD) == 0) { 95 error = EACCES; 96 goto out; 97 } 98 99 error = copyin(elements, &num_mapped, sizeof (uint_t)); 100 if (error) { 101 error = EFAULT; 102 goto out; 103 } 104 105 num_in = num_mapped; 106 model = get_udatamodel(); 107 if (model != DATAMODEL_NATIVE) { 108 ASSERT(model == DATAMODEL_ILP32); 109 convert_64to32 = 1; 110 } 111 112 if (flags & MMOBJ_PADDING) { 113 if (convert_64to32) { 114 size32_t padding32; 115 error = copyin(arg, &padding32, sizeof (padding32)); 116 padding = padding32; 117 } else { 118 error = copyin(arg, &padding, sizeof (padding)); 119 } 120 if (error) { 121 error = EFAULT; 122 goto out; 123 } 124 125 /* 126 * Need to catch overflow here for the 64 bit case. For the 127 * 32 bit case, overflow would round up to 4G which would 128 * not be able to fit in any address space and thus ENOMEM 129 * would be returned after calling into mmapobj. 130 */ 131 if (padding) { 132 padding = P2ROUNDUP(padding, PAGESIZE); 133 if (padding == 0) { 134 error = ENOMEM; 135 goto out; 136 } 137 } 138 /* turn off padding if no bytes were requested */ 139 if (padding == 0) { 140 flags = flags & (~MMOBJ_PADDING); 141 } 142 } 143 144 if (num_mapped > MOBJ_STACK_SEGS) { 145 num_mapped = MOBJ_STACK_SEGS; 146 } 147 retry: 148 error = mmapobj(vp, flags, mrp, &num_mapped, padding, fp->f_cred); 149 150 if (error == E2BIG && alloc_num == 0) { 151 if (num_mapped > MOBJ_STACK_SEGS && num_mapped <= num_in) { 152 mrp = kmem_alloc(sizeof (mmapobj_result_t) * num_mapped, 153 KM_SLEEP); 154 alloc_num = num_mapped; 155 goto retry; 156 } 157 } 158 159 old_error = error; 160 if (error == 0 || error == E2BIG) { 161 error = copyout(&num_mapped, elements, sizeof (uint_t)); 162 if (error) { 163 error = EFAULT; 164 /* 165 * We only mapped in segments if the mmapobj call 166 * succeeded, so only unmap for that case. 167 */ 168 if (old_error == 0) { 169 mmapobj_unmap(mrp, num_mapped, num_mapped, 0); 170 } 171 } else if (num_in < num_mapped) { 172 ASSERT(old_error == E2BIG); 173 error = E2BIG; 174 } else { 175 if (convert_64to32) { 176 mmapobj_result32_t *mrp32; 177 /* Need to translate from 64bit to 32bit */ 178 mrp32 = kmem_alloc(num_mapped * sizeof (*mrp32), 179 KM_SLEEP); 180 mmapobj_copy_64to32(mrp, mrp32, num_mapped); 181 error = copyout(mrp32, (void *)storage, 182 num_mapped * sizeof (mmapobj_result32_t)); 183 kmem_free(mrp32, num_mapped * sizeof (*mrp32)); 184 } else { 185 error = copyout(mrp, (void *)storage, 186 num_mapped * sizeof (mmapobj_result_t)); 187 } 188 if (error) { 189 error = EFAULT; 190 mmapobj_unmap(mrp, num_mapped, num_mapped, 0); 191 } 192 } 193 } 194 195 /* 196 * If stack_mr was not large enough, then we had to allocate 197 * a larger piece of memory to hold the mmapobj_result array. 198 */ 199 if (alloc_num != 0) { 200 ASSERT(mrp != stack_mr); 201 ASSERT(num_mapped > MOBJ_STACK_SEGS); 202 kmem_free(mrp, 203 alloc_num * sizeof (mmapobj_result_t)); 204 } 205 206 out: 207 releasef(fd); 208 if (error) { 209 return (set_errno(error)); 210 } else { 211 return (0); 212 } 213 } 214