/* * * Copyright (c) 2003 The Regents of the University of California. All * rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * - Neither the name of the University nor the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * */ /* * FUSD - The Framework for UserSpace Devices - Example program * * This example creates a a mmap-able buffer. */ #include #include #include #include #include #include #include #include "fusd.h" #define MIN(x, y) ((x) < (y) ? (x) : (y)) #define BUFFER_SIZE 4096 static char *mmap_buffer; static void hexdump(void *ptr_r, int size) { int J, I; unsigned char *ptr = ptr_r; unsigned long Addr = 0; if (ptr == NULL) { puts("NULL POINTER"); puts("-------------------------------------------------------------------------------------"); return; } while (Addr <= size) { for (J = 0; J < 2; J++) { printf("%08p: ", Addr + ptr); for (I = 0; I < 16; I++, Addr++) { if (Addr <= size) { printf("%02lX ", (unsigned char) ptr[Addr]); } else { printf(" "); } } printf(" | "); Addr -= 16; for (I = 0; I < 16; I++, Addr++) { if (Addr <= size) { putchar(isprint(ptr[Addr]) ? ptr[Addr] : '.'); } else { putchar(' '); } } puts(""); } } puts("-------------------------------------------------------------------------------------"); } ssize_t mmaptest_read(struct fusd_file_info *file, char *user_buffer, size_t user_length, loff_t *offset) { int len; if (*offset > BUFFER_SIZE) { return 0; } len = MIN(user_length + (*offset), BUFFER_SIZE); memcpy(user_buffer, mmap_buffer + (*offset), len); *offset += len; return len; } int tester_mmap(struct fusd_file_info *file, int offset, size_t length, int prot, int flags, void **addr, size_t *out_length) { printf("Got a mmap request from PID:%d [offset=%d, size=%d, prot=%X, flags=%X, addr=%p]\n", file->pid, offset, length, prot, flags, *addr); if (length <= BUFFER_SIZE) { *addr = mmap_buffer; *out_length = BUFFER_SIZE; return 0; } return -1; } int do_open(struct fusd_file_info *file) { /* opens and closes always succeed */ return 0; } int do_close(struct fusd_file_info *file) { /* Show content of the buffer */ hexdump(mmap_buffer, 512); return 0; } struct fusd_file_operations drums_fops = { open: do_open, read: mmaptest_read, mmap: tester_mmap, close: do_close }; int main(int argc, char *argv[]) { int i; mmap_buffer = (char *)mmap(NULL, BUFFER_SIZE, PROT_READ|PROT_WRITE, MAP_SHARED|MAP_ANONYMOUS, -1, 0); if (fusd_register("mmap-tester", "mmaptest", "mmap-tester", 0666, NULL, &drums_fops) < 0) { fprintf(stderr, "mmap-tester register failed: %m\n"); return -1; } memset(mmap_buffer, 0xAA, BUFFER_SIZE); fprintf(stderr, "calling fusd_run...\n"); fusd_run(); return 0; }