diff options
Diffstat (limited to 'tmpfs/tmpfs.c')
| -rw-r--r-- | tmpfs/tmpfs.c | 447 |
1 files changed, 447 insertions, 0 deletions
diff --git a/tmpfs/tmpfs.c b/tmpfs/tmpfs.c new file mode 100644 index 00000000..718c6d84 --- /dev/null +++ b/tmpfs/tmpfs.c @@ -0,0 +1,447 @@ +/* Main program and global state for tmpfs. + Copyright (C) 2000,01,02 Free Software Foundation, Inc. + +This file is part of the GNU Hurd. + +The GNU Hurd 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. + +The GNU Hurd 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 the GNU Hurd; see the file COPYING. If not, write to +the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ + +#include <argp.h> +#include <argz.h> +#include <string.h> +#include <inttypes.h> +#include <error.h> + +#include "tmpfs.h" +#include <limits.h> +#include <version.h> +#include <fcntl.h> +#include <hurd.h> +#include <hurd/paths.h> + +char *diskfs_server_name = "tmpfs"; +char *diskfs_server_version = HURD_VERSION; +char *diskfs_extra_version = "GNU Hurd"; +char *diskfs_disk_name = "none"; + +/* We ain't got to show you no stinkin' sync'ing. */ +int diskfs_default_sync_interval = 0; + +/* We must supply some claimed limits, though we don't impose any new ones. */ +int diskfs_link_max = (1ULL << (sizeof (nlink_t) * CHAR_BIT)) - 1; +int diskfs_name_max = 255; /* dirent d_namlen limit */ +int diskfs_maxsymlinks = 8; + +/* Yeah, baby, we do it all! */ +int diskfs_shortcut_symlink = 1; +int diskfs_shortcut_chrdev = 1; +int diskfs_shortcut_blkdev = 1; +int diskfs_shortcut_fifo = 1; +int diskfs_shortcut_ifsock = 1; + +struct node *diskfs_root_node; +mach_port_t default_pager; + +off_t tmpfs_page_limit, tmpfs_space_used; +mode_t tmpfs_root_mode = -1; + +error_t +diskfs_set_statfs (struct statfs *st) +{ + fsblkcnt_t pages; + + st->f_type = FSTYPE_MEMFS; + st->f_fsid = getpid (); + + st->f_bsize = vm_page_size; + st->f_blocks = tmpfs_page_limit; + + pthread_spin_lock (&diskfs_node_refcnt_lock); + st->f_files = num_files; + pages = round_page (tmpfs_space_used) / vm_page_size; + pthread_spin_unlock (&diskfs_node_refcnt_lock); + + st->f_bfree = pages < tmpfs_page_limit ? tmpfs_page_limit - pages : 0; + st->f_bavail = st->f_bfree; + st->f_ffree = st->f_bavail / sizeof (struct disknode); /* Well, sort of. */ + + return 0; +} + + +error_t +diskfs_set_hypermetadata (int wait, int clean) +{ + /* All the state always just lives in core, so we have nothing to do. */ + return 0; +} + +void +diskfs_sync_everything (int wait) +{ +} + +error_t +diskfs_reload_global_state () +{ + return 0; +} + +int diskfs_synchronous = 0; + +#define OPT_SIZE 600 /* --size */ + +static const struct argp_option options[] = +{ + {"mode", 'm', "MODE", 0, "Permissions (octal) for root directory"}, + {"size", OPT_SIZE, "MAX-BYTES", 0, "Maximum size"}, + {NULL,} +}; + +struct option_values +{ + off_t size; + mode_t mode; +}; + +/* Parse the size string ARG, and set *NEWSIZE with the resulting size. */ +static error_t +parse_opt_size (const char *arg, struct argp_state *state, off_t *newsize) +{ + char *end = NULL; + intmax_t size = strtoimax (arg, &end, 0); + if (end == NULL || end == arg) + { + argp_error (state, "argument must be a number"); + return EINVAL; + } + if (size < 0) + { + argp_error (state, "negative size not meaningful"); + return EINVAL; + } + switch (*end) + { + case 'g': + case 'G': + size <<= 10; + case 'm': + case 'M': + size <<= 10; + case 'k': + case 'K': + size <<= 10; + break; + case '%': + { + /* Set as a percentage of the machine's physical memory. */ + struct vm_statistics vmstats; + error_t err = vm_statistics (mach_task_self (), &vmstats); + if (err) + { + argp_error (state, "cannot find total physical memory: %s", + strerror (err)); + return err; + } + size = round_page ((((vmstats.free_count + + vmstats.active_count + + vmstats.inactive_count + + vmstats.wire_count) + * vm_page_size) + * size + 99) / 100); + break; + } + } + size = (off_t) size; + if (size < 0) + { + argp_error (state, "size too large"); + return EINVAL; + } + + *newsize = size; + + return 0; +} + +/* Parse a command line option. */ +static error_t +parse_opt (int key, char *arg, struct argp_state *state) +{ + /* We save our parsed values in this structure, hung off STATE->hook. + Only after parsing all options successfully will we use these values. */ + struct option_values *values = state->hook; + + switch (key) + { + case ARGP_KEY_INIT: + state->child_inputs[0] = state->input; + values = malloc (sizeof *values); + if (values == 0) + return ENOMEM; + state->hook = values; + values->size = -1; + values->mode = -1; + break; + case ARGP_KEY_FINI: + free (values); + state->hook = 0; + break; + + case 'm': /* --mode=OCTAL */ + { + char *end = NULL; + mode_t mode = strtoul (arg, &end, 8); + if (end == NULL || end == arg) + { + argp_error (state, "argument must be an octal number"); + return EINVAL; + } + if (mode & S_IFMT) + { + argp_error (state, "invalid bits in mode"); + return EINVAL; + } + values->mode = mode; + } + break; + + case OPT_SIZE: /* --size=MAX-BYTES */ + { + error_t err = parse_opt_size (arg, state, &values->size); + if (err) + return err; + } + break; + + case ARGP_KEY_NO_ARGS: + if (values->size < 0) + { + argp_error (state, "must supply maximum size"); + return EINVAL; + } + break; + + case ARGP_KEY_ARGS: + if (state->argv[state->next + 1] != 0) + { + argp_error (state, "too many arguments"); + return EINVAL; + } + else if (values->size >= 0) + { + if (strcmp (state->argv[state->next], "tmpfs") != 0) + { + argp_error (state, "size specified with --size and argument is not \"tmpfs\""); + return EINVAL; + } + } + else + { + error_t err = parse_opt_size (state->argv[state->next], state, + &values->size); + if (err) + return err; + } + break; + + case ARGP_KEY_SUCCESS: + /* All options parse successfully, so implement ours if possible. */ + tmpfs_page_limit = values->size / vm_page_size; + tmpfs_root_mode = values->mode; + break; + + default: + return ARGP_ERR_UNKNOWN; + } + return 0; +} + +/* Override the standard diskfs routine so we can add our own output. */ +error_t +diskfs_append_args (char **argz, size_t *argz_len) +{ + error_t err; + + /* Get the standard things. */ + err = diskfs_append_std_options (argz, argz_len); + + if (!err) + { + off_t lim = tmpfs_page_limit * vm_page_size; + char buf[100], sfx; +#define S(n, c) if ((lim & ((1 << n) - 1)) == 0) sfx = c, lim >>= n + S (30, 'G'); else S (20, 'M'); else S (10, 'K'); else sfx = '\0'; +#undef S + snprintf (buf, sizeof buf, "%Ld%c", lim, sfx); + err = argz_add (argz, argz_len, buf); + } + + return err; +} + +/* Handling of operations for the ports in diskfs_port_bucket, calling + * demuxer for each incoming message */ +static void * +diskfs_thread_function (void *demuxer) +{ + static int thread_timeout = 1000 * 60 * 2; /* two minutes */ + error_t err; + + do + { + ports_manage_port_operations_multithread (diskfs_port_bucket, + (ports_demuxer_type) demuxer, + thread_timeout, + 0, + 0); + err = diskfs_shutdown (0); + } + while (err); + + exit (0); + /* NOTREACHED */ + return NULL; +} + + +/* Add our startup arguments to the standard diskfs set. */ +static const struct argp_child startup_children[] = + {{&diskfs_startup_argp}, {0}}; +static struct argp startup_argp = {options, parse_opt, "MAX-BYTES", "\ +\v\ +MAX-BYTES may be followed by k or K for kilobytes,\n\ +m or M for megabytes, g or G for gigabytes.", + startup_children}; + +/* Similarly at runtime. */ +static const struct argp_child runtime_children[] = + {{&diskfs_std_runtime_argp}, {0}}; +static struct argp runtime_argp = {options, parse_opt, 0, 0, runtime_children}; + +struct argp *diskfs_runtime_argp = (struct argp *)&runtime_argp; + + + +int +main (int argc, char **argv) +{ + error_t err; + mach_port_t bootstrap, realnode, host_priv; + pthread_t pthread_id; + struct stat st; + + err = argp_parse (&startup_argp, argc, argv, ARGP_IN_ORDER, NULL, NULL); + assert_perror (err); + + task_get_bootstrap_port (mach_task_self (), &bootstrap); + if (bootstrap == MACH_PORT_NULL) + error (2, 0, "Must be started as a translator"); + + /* Get our port to the default pager. Without that, + we have no place to put file contents. */ + err = get_privileged_ports (&host_priv, NULL); + if (err == EPERM) + { + default_pager = file_name_lookup (_SERVERS_DEFPAGER, O_EXEC, 0); + if (default_pager == MACH_PORT_NULL) + error (0, errno, _SERVERS_DEFPAGER); + } + else if (err) + error (0, err, "Cannot get host privileged port"); + else + { + err = vm_set_default_memory_manager (host_priv, &default_pager); + mach_port_deallocate (mach_task_self (), host_priv); + if (err) + error (0, err, "Cannot get default pager port"); + } + if (default_pager == MACH_PORT_NULL) + error (0, 0, "files cannot have contents with no default pager port"); + + /* Initialize the diskfs library. Must come before any other diskfs call. */ + err = diskfs_init_diskfs (); + if (err) + error (4, err, "init"); + + err = diskfs_alloc_node (0, S_IFDIR, &diskfs_root_node); + if (err) + error (4, err, "cannot create root directory"); + + /* Like diskfs_spawn_first_thread. But do it manually, without timeout */ + err = pthread_create (&pthread_id, NULL, diskfs_thread_function, + diskfs_demuxer); + if (!err) + pthread_detach (pthread_id); + else + { + errno = err; + perror ("pthread_create"); + } + + /* Now that we are all set up to handle requests, and diskfs_root_node is + set properly, it is safe to export our fsys control port to the + outside world. */ + realnode = diskfs_startup_diskfs (bootstrap, 0); + diskfs_root_node->dn_stat.st_mode = S_IFDIR; + + /* Propagate permissions, owner, etc. from underlying node to + the root directory of the new (empty) filesystem. */ + err = io_stat (realnode, &st); + if (err) + { + error (0, err, "cannot stat underlying node"); + if (tmpfs_root_mode == -1) + diskfs_root_node->dn_stat.st_mode |= 0777 | S_ISVTX; + else + diskfs_root_node->dn_stat.st_mode |= tmpfs_root_mode; + diskfs_root_node->dn_set_ctime = 1; + diskfs_root_node->dn_set_mtime = 1; + diskfs_root_node->dn_set_atime = 1; + } + else + { + if (tmpfs_root_mode == -1) + { + diskfs_root_node->dn_stat.st_mode |= st.st_mode &~ S_IFMT; + if (S_ISREG (st.st_mode) && (st.st_mode & 0111) == 0) + /* There are no execute bits set, as by default on a plain file. + For the virtual directory, set execute bits where read bits are + set on the underlying plain file. */ + diskfs_root_node->dn_stat.st_mode |= (st.st_mode & 0444) >> 2; + } + else + diskfs_root_node->dn_stat.st_mode |= tmpfs_root_mode; + diskfs_root_node->dn_stat.st_uid = st.st_uid; + diskfs_root_node->dn_stat.st_author = st.st_author; + diskfs_root_node->dn_stat.st_gid = st.st_gid; + diskfs_root_node->dn_stat.st_atim = st.st_atim; + diskfs_root_node->dn_stat.st_mtim = st.st_mtim; + diskfs_root_node->dn_stat.st_ctim = st.st_ctim; + diskfs_root_node->dn_stat.st_flags = st.st_flags; + } + diskfs_root_node->dn_stat.st_mode &= ~S_ITRANS; + diskfs_root_node->dn_stat.st_mode |= S_IROOT; + diskfs_root_node->dn_stat.st_nlink = 2; + + /* We must keep the REALNODE send right to remain the active + translator for the underlying node. */ + + pthread_mutex_unlock (&diskfs_root_node->lock); + + /* and so we die, leaving others to do the real work. */ + pthread_exit (NULL); + /* NOTREACHED */ + return 0; +} |