/* A translator for doing I/O to mach kernel devices. Copyright (C) 1995 Free Software Foundation, Inc. Written by Miles Bader This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include #include #include #include #include #include #include #include #include #include #include "open.h" #include "dev.h" #include "ptypes.h" #ifdef MSG #define DEBUG(what) \ ((debug) \ ? ({ mutex_lock(&debug_lock); what; mutex_unlock(&debug_lock);0;}) \ : 0) #else #define DEBUG(what) 0 #endif /* ---------------------------------------------------------------- */ #define USAGE "Usage: %s [OPTION...] DEVICE\n" static void usage(int status) { if (status != 0) fprintf(stderr, "Try `%s --help' for more information.\n", program_invocation_name); else { printf(USAGE, program_invocation_name); printf("\ \n\ -d, --devnum=NUM Give DEVICE a device number NUM\n\ -r, --readonly Disable writing to DEVICE\n\ -p, --seekable Enable seeking if DEVICE is serial\n\ -s, --serial Indicate that DEVICE has a single R/W point\n\ -b, --buffered, --block Open DEVICE in `block' mode, which allows reads\n\ or writes less than a single block and buffers\n\ I/O to the actual device. By default, all reads\n\ and writes are made directly to the device,\n\ with no buffering, and any sub-block-size I/O\n\ is padded to the nearest full block.\n\ -B NUM, --block-size=NUM Use a block size of NUM, which must be an integer\n\ multiple of DEVICE's real block size\n\ "); } exit(status); } #define SHORT_OPTIONS "bB:d:D:?rpsu" static struct option options[] = { {"block-size", required_argument, 0, 'B'}, {"debug", required_argument, 0, 'D'}, {"help", no_argument, 0, '?'}, {"devnum", required_argument, 0, 'm'}, {"block", no_argument, 0, 'b'}, {"buffered", no_argument, 0, 'b'}, {"readonly", no_argument, 0, 'r'}, {"seekable", no_argument, 0, 'p'}, {"serial", no_argument, 0, 's'}, {0, 0, 0, 0} }; /* ---------------------------------------------------------------- */ /* A struct dev for the open kernel device. */ static struct dev *device = NULL; /* And a lock to arbitrate changes to it. */ static struct mutex device_lock; /* Desired device parameters specified by the user. */ static char *device_name = NULL; static int device_flags = 0; static int device_block_size = 0; /* A unixy device number to return when the device is stat'd. */ static int device_number = 0; /* A stream on which we can print debugging message. */ FILE *debug = NULL; /* A lock to use while doing so. */ struct mutex debug_lock; void main(int argc, char *argv[]) { int opt; error_t err; mach_port_t bootstrap; while ((opt = getopt_long(argc, argv, SHORT_OPTIONS, options, 0)) != EOF) switch (opt) { case 'r': device_flags |= DEV_READONLY; break; case 's': device_flags |= DEV_SERIAL; break; case 'b': device_flags |= DEV_BUFFERED; break; case 'p': device_flags |= DEV_SEEKABLE; break; case 'B': device_block_size = atoi(optarg); break; case 'd': device_number = atoi(optarg); break; case 'D': debug = fopen(optarg, "w+"); setlinebuf(debug); break; case '?': usage(0); default: usage(1); } mutex_init(&debug_lock); if (device_flags & DEV_READONLY) /* Catch illegal writes at the point of open. */ trivfs_allow_open &= ~O_WRITE; if (argv[optind] == NULL || argv[optind + 1] != NULL) { fprintf(stderr, USAGE, program_invocation_name); usage(1); } device_name = argv[optind]; task_get_bootstrap_port (mach_task_self (), &bootstrap); if (bootstrap == MACH_PORT_NULL) error(2, 0, "Must be started as a translator"); /* Reply to our parent */ err = trivfs_startup(bootstrap, PT_FSYS, PT_NODE, NULL); if (err) error(3, err, "Contacting parent"); /* Open the device only when necessary. */ device = NULL; mutex_init(&device_lock); /* Launch. */ ports_manage_port_operations_multithread (); exit(0); } /* Called whenever someone tries to open our node (even for a stat). We delay opening the kernel device until this point, as we can usefully return errors from here. */ static error_t check_open_hook (struct trivfs_control *trivfs_control, uid_t *uids, u_int nuids, gid_t *gids, u_int ngids, int flags) { error_t err = 0; mutex_lock(&device_lock); if (device == NULL) /* Try and open the device. */ { err = dev_open(device_name, device_flags, device_block_size, &device); if (err) device = NULL; if (err && (flags & (O_READ|O_WRITE)) == 0) /* If we're not opening for read or write, then just ignore the error, as this allows stat to word correctly. XXX */ err = 0; } mutex_unlock(&device_lock); return err; } static void open_hook(struct trivfs_peropen *peropen) { struct dev *dev = device; if (dev) open_create(dev, (struct open **)&peropen->hook); } static void close_hook(struct trivfs_peropen *peropen) { if (peropen->hook) open_free(peropen->hook); } static void close_device(int aquire_lock) { DEBUG(fprintf(debug, "Closing device\n")); if (aquire_lock) mutex_lock(&device_lock); if (device) { dev_close(device); device = NULL; } if (aquire_lock) mutex_unlock(&device_lock); } static void clean_exit(int status, int aquire_lock) { DEBUG(fprintf(debug, "Cleaning up and exiting (status = %d)...\n", status)); close_device(aquire_lock); DEBUG({fprintf(debug, "Bye!\n"); fclose(debug); debug = NULL;}); exit(0); } /* ---------------------------------------------------------------- */ /* Trivfs hooks */ int trivfs_fstype = FSTYPE_DEV; int trivfs_fsid = 0; int trivfs_support_read = 1; int trivfs_support_write = 1; int trivfs_support_exec = 0; int trivfs_allow_open = O_READ | O_WRITE; int trivfs_protid_porttypes[] = {PT_NODE}; int trivfs_cntl_porttypes[] = {PT_FSYS}; int trivfs_protid_nporttypes = 1; int trivfs_cntl_nporttypes = 1; void trivfs_modify_stat (struct stat *st) { struct dev *dev = device; if (dev) { vm_size_t size = dev->size; if (dev->block_size > 1) st->st_blksize = dev->block_size; st->st_size = size; st->st_blocks = size / 512; if (dev_is(dev, DEV_READONLY)) st->st_mode &= ~(S_IWUSR | S_IWGRP | S_IWOTH); st->st_mode &= ~S_IFMT; st->st_mode |= dev_is(dev, DEV_BUFFERED) ? S_IFBLK : S_IFCHR; } else /* Try and do things without an open device... */ { st->st_blksize = device_block_size; st->st_size = 0; st->st_blocks = 0; st->st_mode &= ~S_IFMT; st->st_mode |= (device_flags & DEV_BUFFERED) ? S_IFBLK : S_IFCHR; if (device_flags & DEV_READONLY) st->st_mode &= ~(S_IWUSR | S_IWGRP | S_IWOTH); } st->st_rdev = device_number; } error_t trivfs_goaway (int flags, mach_port_t realnode, int ctltype, int pitype) { DEBUG(fprintf(debug, "trivfs_goaway(0x%x, %d, %d, %d)\n", flags, realnode, ctltype, pitype)); mutex_lock(&device_lock); if (device == NULL || (flags & FSYS_GOAWAY_FORCE)) /* Go away immediately. */ if (flags & FSYS_GOAWAY_NOSYNC) /* Don't clean up. */ exit(0); else clean_exit(0, FALSE); mutex_lock(&device_lock); /* Complain that there are still users. */ return EBUSY; } /* If this variable is set, it is called every time an open happens. UIDS, GIDS, and FLAGS are from the open; CNTL identifies the node being opened. This call need not check permissions on the underlying node. If the open call should block, then return EWOULDBLOCK. Other errors are immediately reflected to the user. If O_NONBLOCK is not set in FLAGS and EWOULDBLOCK is returned, then call trivfs_complete_open when all pending open requests for this file can complete. */ error_t (*trivfs_check_open_hook)(struct trivfs_control *trivfs_control, uid_t *uids, u_int nuids, gid_t *gids, u_int ngids, int flags) = check_open_hook; /* If this variable is set, it is called every time a new peropen structure is created and initialized. */ void (*trivfs_peropen_create_hook)(struct trivfs_peropen *) = open_hook; /* If this variable is set, it is called every time a peropen structure is about to be destroyed. */ void (*trivfs_peropen_destroy_hook) (struct trivfs_peropen *) = close_hook; /* Sync this filesystem. */ kern_return_t trivfs_S_fsys_syncfs (struct trivfs_control *cntl, mach_port_t reply, mach_msg_type_name_t replytype, int wait, int dochildren) { struct dev *dev = device; DEBUG(fprintf(debug, "Syncing filesystem...\n")); if (dev) return dev_sync(dev, wait); else return 0; } /* ---------------------------------------------------------------- */ /* Ports hooks */ void (*ports_cleanroutines[])(void *) = { [PT_FSYS] = trivfs_clean_cntl, [PT_NODE] = trivfs_clean_protid, }; int ports_demuxer (mach_msg_header_t *inp, mach_msg_header_t *outp) { int ok; #ifdef MSG static int next_msg_num = 0; int msg_num; #endif DEBUG(msg_num = next_msg_num++; fprintf(debug, "port_demuxer(%d) [%d]\n", inp->msgh_id, msg_num);); ok = pager_demuxer(inp, outp) || trivfs_demuxer(inp, outp); DEBUG(fprintf(debug, "port_demuxer(%d) [%d] done!\n", inp->msgh_id,msg_num)); return ok; } /* This will be called whenever there have been no requests to the server for a significant period of time. NHARD is the number of live hard ports; NSOFT is the number of live soft ports. This function is called while an internal lock is held, so it cannot reliably call any other functions of the ports library. */ void ports_notice_idle (int nhard, int nsoft) { DEBUG(fprintf(debug, "ports_notice_idle(%d, %d)\n", nhard, nsoft)); if (nhard == 0) clean_exit(0, TRUE); } /* This will be called whenever there are no hard ports or soft ports allocated. This function is called while an internal lock is held, so it cannot reliably call any other functions of the ports library. */ void ports_no_live_ports () { DEBUG(fprintf(debug, "ports_no_live_ports()\n")); clean_exit(0, TRUE); } /* This will be called whenever there are no hard ports allocated but there are still some soft ports. This function is called while an internal lock is held, so it cannot reliably call any other functions of the ports library. */ void ports_no_hard_ports () { DEBUG(fprintf(debug, "ports_no_hard_ports()\n")); close_device(TRUE); }