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 /* 23 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 #pragma ident "%Z%%M% %I% %E% SMI" 28 29 #include <errno.h> 30 #include <unistd.h> 31 #include <sys/uio.h> 32 #include <fcntl.h> 33 #include <sys/types.h> 34 #include <sys/stat.h> 35 #include <alloca.h> 36 #include <string.h> 37 #include <sys/lx_syscall.h> 38 #include <sys/lx_misc.h> 39 #include <sys/lx_types.h> 40 41 static int 42 lx_is_directory(int fd) 43 { 44 struct stat64 sbuf; 45 46 if (fstat64(fd, &sbuf) < 0) 47 sbuf.st_mode = 0; 48 49 return ((sbuf.st_mode & S_IFMT) == S_IFDIR); 50 } 51 52 int 53 lx_read(uintptr_t p1, uintptr_t p2, uintptr_t p3) 54 { 55 int fd = (int)p1; 56 void *buf = (void *)p2; 57 size_t nbyte = (size_t)p3; 58 ssize_t ret; 59 60 if (lx_is_directory(fd)) 61 return (-EISDIR); 62 63 if ((ret = read(fd, buf, nbyte)) < 0) 64 return (-errno); 65 66 return (ret); 67 } 68 69 int 70 lx_pread64(uintptr_t p1, uintptr_t p2, uintptr_t p3, uintptr_t p4, uintptr_t p5) 71 { 72 int fd = (int)p1; 73 void *buf = (void *)p2; 74 size_t nbyte = (size_t)p3; 75 uintptr_t off_lo = p4; 76 uintptr_t off_hi = p5; 77 ssize_t ret; 78 79 if (lx_is_directory(fd)) 80 return (-EISDIR); 81 82 ret = pread64(fd, buf, nbyte, (off64_t)LX_32TO64(off_lo, off_hi)); 83 84 if (ret < 0) 85 return (-errno); 86 87 return (ret); 88 } 89 90 /* 91 * On Linux, the pwrite(2) system call behaves identically to Solaris except 92 * in the case of the file being opened with O_APPEND. In that case Linux's 93 * pwrite(2) ignores the offset parameter and instead appends the data to the 94 * file without modifying the current seek pointer. 95 */ 96 int 97 lx_pwrite64(uintptr_t p1, uintptr_t p2, uintptr_t p3, uintptr_t p4, 98 uintptr_t p5) 99 { 100 int fd = (int)p1; 101 void *buf = (void *)p2; 102 size_t nbyte = (size_t)p3; 103 uintptr_t off_lo = p4; 104 uintptr_t off_hi = p5; 105 ssize_t ret; 106 int rval; 107 struct stat64 statbuf; 108 109 if ((rval = fcntl(fd, F_GETFL, 0)) < 0) 110 return (-errno); 111 112 if (!(rval & O_APPEND)) { 113 ret = pwrite64(fd, buf, nbyte, 114 (off64_t)LX_32TO64(off_lo, off_hi)); 115 } else if ((ret = fstat64(fd, &statbuf)) == 0) { 116 ret = pwrite64(fd, buf, nbyte, statbuf.st_size); 117 } 118 119 if (ret < 0) 120 return (-errno); 121 122 return (ret); 123 } 124 125 /* 126 * Implementation of Linux readv() and writev() system calls. 127 * 128 * The Linux system calls differ from the Solaris system calls in a few key 129 * areas: 130 * 131 * - On Solaris, the maximum number of I/O vectors that can be passed to readv() 132 * or writev() is IOV_MAX (16). Linux has a much larger restriction (1024). 133 * 134 * - Passing 0 as a vector count is an error on Solaris, but on Linux results 135 * in a return value of 0. Even though the man page says the opposite. 136 * 137 * - If the Nth vector results in an error, Solaris will return an error code 138 * for the entire operation. Linux only returns an error if there has been 139 * no data transferred yet. Otherwise, it returns the number of bytes 140 * transferred up until that point. 141 * 142 * In order to accomodate these differences, we implement these functions as a 143 * series of ordinary read() or write() calls. 144 */ 145 146 #define LX_IOV_MAX 1024 /* Also called MAX_IOVEC */ 147 148 static int 149 lx_iovec_copy_and_check(const struct iovec *iovp, struct iovec *iov, int count) 150 { 151 int i; 152 ssize_t cnt = 0; 153 154 if (uucopy(iovp, (void *)iov, count * sizeof (struct iovec)) != 0) 155 return (-errno); 156 157 for (i = 0; i < count; i++) { 158 cnt += iov[i].iov_len; 159 if (iov[i].iov_len < 0 || cnt < 0) 160 return (-EINVAL); 161 } 162 163 return (0); 164 } 165 166 int 167 lx_readv(uintptr_t p1, uintptr_t p2, uintptr_t p3) 168 { 169 int fd = (int)p1; 170 const struct iovec *iovp = (const struct iovec *)p2; 171 int count = (int)p3; 172 struct iovec *iov; 173 ssize_t total = 0, ret; 174 int i; 175 176 if (count == 0) 177 return (0); 178 179 if (count < 0 || count > LX_IOV_MAX) 180 return (-EINVAL); 181 182 if (lx_is_directory(fd)) 183 return (-EISDIR); 184 185 iov = SAFE_ALLOCA(count * sizeof (struct iovec)); 186 if (iov == NULL) 187 return (-ENOMEM); 188 if ((ret = lx_iovec_copy_and_check(iovp, iov, count)) != 0) 189 return (ret); 190 191 for (i = 0; i < count; i++) { 192 ret = read(fd, iov[i].iov_base, iov[i].iov_len); 193 194 if (ret < 0) { 195 if (total > 0) 196 return (total); 197 return (-errno); 198 } 199 200 total += ret; 201 } 202 203 return (total); 204 } 205 206 int 207 lx_writev(uintptr_t p1, uintptr_t p2, uintptr_t p3) 208 { 209 int fd = (int)p1; 210 const struct iovec *iovp = (const struct iovec *)p2; 211 int count = (int)p3; 212 struct iovec *iov; 213 ssize_t total = 0, ret; 214 int i; 215 216 if (count == 0) 217 return (0); 218 219 if (count < 0 || count > LX_IOV_MAX) 220 return (-EINVAL); 221 222 iov = SAFE_ALLOCA(count * sizeof (struct iovec)); 223 if (iov == NULL) 224 return (-ENOMEM); 225 if ((ret = lx_iovec_copy_and_check(iovp, iov, count)) != 0) 226 return (ret); 227 228 for (i = 0; i < count; i++) { 229 ret = write(fd, iov[i].iov_base, iov[i].iov_len); 230 231 if (ret < 0) { 232 if (total > 0) 233 return (total); 234 return (-errno); 235 } 236 237 total += ret; 238 } 239 240 return (total); 241 }