toaruos/modules/tmpfs.c

432 lines
11 KiB
C

/* vim: tabstop=4 shiftwidth=4 noexpandtab
* This file is part of ToaruOS and is released under the terms
* of the NCSA / University of Illinois License - see LICENSE.md
* Copyright (C) 2014 Kevin Lange
*/
#include <system.h>
#include <logging.h>
#include <fs.h>
#include <version.h>
#include <process.h>
#include <module.h>
#include <mod/tmpfs.h>
/* 1KB */
#define BLOCKSIZE 1024
#define TMPFS_TYPE_FILE 1
#define TMPFS_TYPE_DIR 2
uint8_t volatile tmpfs_lock = 0;
struct tmpfs_dir * tmpfs_root = NULL;
static fs_node_t * tmpfs_from_dir(struct tmpfs_dir * d);
static struct tmpfs_file * tmpfs_file_new(char * name) {
spin_lock(&tmpfs_lock);
struct tmpfs_file * t = malloc(sizeof(struct tmpfs_file));
t->name = strdup(name);
t->type = TMPFS_TYPE_FILE;
t->length = 0;
t->pointers = 2;
t->block_count = 0;
t->mask = 0;
t->uid = 0;
t->gid = 0;
t->atime = now();
t->mtime = t->atime;
t->ctime = t->atime;
t->blocks = malloc(t->pointers * sizeof(char *));
for (size_t i = 0; i < t->pointers; ++i) {
t->blocks[i] = NULL;
}
spin_unlock(&tmpfs_lock);
return t;
}
static struct tmpfs_dir * tmpfs_dir_new(char * name, struct tmpfs_dir * parent) {
spin_lock(&tmpfs_lock);
struct tmpfs_dir * d = malloc(sizeof(struct tmpfs_dir));
d->name = strdup(name);
d->type = TMPFS_TYPE_DIR;
d->mask = 0;
d->uid = 0;
d->gid = 0;
d->atime = now();
d->mtime = d->atime;
d->ctime = d->atime;
d->files = list_create();
spin_unlock(&tmpfs_lock);
return d;
}
static void tmpfs_file_free(struct tmpfs_file * t) {
for (size_t i = 0; i < t->block_count; ++i) {
free(t->blocks[i]);
}
}
static void tmpfs_file_blocks_embiggen(struct tmpfs_file * t) {
t->pointers *= 2;
debug_print(INFO, "Embiggening file %s to %d blocks", t->name, t->pointers);
t->blocks = realloc(t->blocks, sizeof(char *) * t->pointers);
}
static char * tmpfs_file_getset_block(struct tmpfs_file * t, size_t blockid, int create) {
debug_print(INFO, "Reading block %d from file %s", blockid, t->name);
if (create) {
spin_lock(&tmpfs_lock);
while (blockid >= t->pointers) {
tmpfs_file_blocks_embiggen(t);
}
while (blockid >= t->block_count) {
debug_print(INFO, "Allocating block %d for file %s", blockid, t->name);
t->blocks[t->block_count] = malloc(BLOCKSIZE);
t->block_count += 1;
}
spin_unlock(&tmpfs_lock);
} else {
if (blockid >= t->block_count) {
debug_print(CRITICAL, "This will probably end badly.");
return NULL;
}
}
debug_print(WARNING, "Using block %d->0x%x (of %d) on file %s", blockid, t->blocks[blockid], t->block_count, t->name);
return t->blocks[blockid];
}
static uint32_t read_tmpfs(fs_node_t *node, uint32_t offset, uint32_t size, uint8_t *buffer) {
struct tmpfs_file * t = (struct tmpfs_file *)(node->device);
t->atime = now();
uint32_t end;
if (offset + size > t->length) {
end = t->length;
} else {
end = offset + size;
}
debug_print(INFO, "reading from %d to %d", offset, end);
uint32_t start_block = offset / BLOCKSIZE;
uint32_t end_block = end / BLOCKSIZE;
uint32_t end_size = end - end_block * BLOCKSIZE;
uint32_t size_to_read = end - offset;
if (start_block == end_block && offset == end) return 0;
if (end_size == 0) {
end_block--;
}
if (start_block == end_block) {
void *buf = tmpfs_file_getset_block(t, start_block, 0);
memcpy(buffer, (uint8_t *)(((uint32_t)buf) + (offset % BLOCKSIZE)), size_to_read);
return size_to_read;
} else {
uint32_t block_offset;
uint32_t blocks_read = 0;
for (block_offset = start_block; block_offset < end_block; block_offset++, blocks_read++) {
if (block_offset == start_block) {
void *buf = tmpfs_file_getset_block(t, block_offset, 0);
memcpy(buffer, (uint8_t *)(((uint32_t)buf) + (offset % BLOCKSIZE)), BLOCKSIZE - (offset % BLOCKSIZE));
} else {
void *buf = tmpfs_file_getset_block(t, block_offset, 0);
memcpy(buffer + BLOCKSIZE * blocks_read - (offset % BLOCKSIZE), buf, BLOCKSIZE);
}
}
void *buf = tmpfs_file_getset_block(t, end_block, 0);
memcpy(buffer + BLOCKSIZE * blocks_read - (offset % BLOCKSIZE), buf, end_size);
}
return size_to_read;
}
static uint32_t write_tmpfs(fs_node_t *node, uint32_t offset, uint32_t size, uint8_t *buffer) {
struct tmpfs_file * t = (struct tmpfs_file *)(node->device);
t->atime = now();
t->mtime = t->atime;
uint32_t end;
if (offset + size > t->length) {
t->length = offset + size;
}
end = offset + size;
uint32_t start_block = offset / BLOCKSIZE;
uint32_t end_block = end / BLOCKSIZE;
uint32_t end_size = end - end_block * BLOCKSIZE;
uint32_t size_to_read = end - offset;
if (end_size == 0) {
end_block--;
}
if (start_block == end_block) {
void *buf = tmpfs_file_getset_block(t, start_block, 1);
memcpy((uint8_t *)(((uint32_t)buf) + (offset % BLOCKSIZE)), buffer, size_to_read);
return size_to_read;
} else {
uint32_t block_offset;
uint32_t blocks_read = 0;
for (block_offset = start_block; block_offset < end_block; block_offset++, blocks_read++) {
if (block_offset == start_block) {
void *buf = tmpfs_file_getset_block(t, block_offset, 1);
memcpy((uint8_t *)(((uint32_t)buf) + (offset % BLOCKSIZE)), buffer, BLOCKSIZE - (offset % BLOCKSIZE));
} else {
void *buf = tmpfs_file_getset_block(t, block_offset, 1);
memcpy(buf, buffer + BLOCKSIZE * blocks_read - (offset % BLOCKSIZE), BLOCKSIZE);
}
}
void *buf = tmpfs_file_getset_block(t, end_block, 1);
memcpy(buf, buffer + BLOCKSIZE * blocks_read - (offset % BLOCKSIZE), end_size);
}
return size_to_read;
}
static int chmod_tmpfs(fs_node_t * node, int mode) {
struct tmpfs_file * t = (struct tmpfs_file *)(node->device);
/* XXX permissions */
t->mask = mode;
return 0;
}
static void open_tmpfs(fs_node_t * node, unsigned int flags) {
struct tmpfs_file * t = (struct tmpfs_file *)(node->device);
debug_print(WARNING, "---- Opened TMPFS file %s with flags 0x%x ----", t->name, flags);
if (flags & O_TRUNC) {
debug_print(WARNING, "Truncating file %s", t->name);
for (size_t i = 0; i < t->block_count; ++i) {
free(t->blocks[i]);
t->blocks[i] = 0;
}
t->block_count = 0;
t->length = 0;
}
return;
}
static fs_node_t * tmpfs_from_file(struct tmpfs_file * t) {
fs_node_t * fnode = malloc(sizeof(fs_node_t));
memset(fnode, 0x00, sizeof(fs_node_t));
fnode->inode = 0;
strcpy(fnode->name, t->name);
fnode->device = t;
fnode->mask = t->mask;
fnode->uid = t->uid;
fnode->gid = t->gid;
fnode->atime = t->atime;
fnode->ctime = t->ctime;
fnode->mtime = t->mtime;
fnode->flags = FS_FILE;
fnode->read = read_tmpfs;
fnode->write = write_tmpfs;
fnode->open = open_tmpfs;
fnode->close = NULL;
fnode->readdir = NULL;
fnode->finddir = NULL;
fnode->chmod = chmod_tmpfs;
fnode->length = t->length;
fnode->nlink = 1;
return fnode;
}
static struct dirent * readdir_tmpfs(fs_node_t *node, uint32_t index) {
struct tmpfs_dir * d = (struct tmpfs_dir *)node->device;
uint32_t i = 0;
debug_print(NOTICE, "tmpfs - readdir id=%d", index);
if (index == 0) {
struct dirent * out = malloc(sizeof(struct dirent));
memset(out, 0x00, sizeof(struct dirent));
out->ino = 0;
strcpy(out->name, ".");
return out;
}
if (index == 1) {
struct dirent * out = malloc(sizeof(struct dirent));
memset(out, 0x00, sizeof(struct dirent));
out->ino = 0;
strcpy(out->name, "..");
return out;
}
index -= 2;
if (index >= d->files->length) return NULL;
foreach(f, d->files) {
if (i == index) {
struct tmpfs_file * t = (struct tmpfs_file *)f->value;
struct dirent * out = malloc(sizeof(struct dirent));
memset(out, 0x00, sizeof(struct dirent));
out->ino = (uint32_t)t;
strcpy(out->name, t->name);
return out;
} else {
++i;
}
}
return NULL;
}
static fs_node_t * finddir_tmpfs(fs_node_t * node, char * name) {
if (!name) return NULL;
struct tmpfs_dir * d = (struct tmpfs_dir *)node->device;
spin_lock(&tmpfs_lock);
foreach(f, d->files) {
struct tmpfs_file * t = (struct tmpfs_file *)f->value;
if (!strcmp(name, t->name)) {
spin_unlock(&tmpfs_lock);
switch (t->type) {
case TMPFS_TYPE_FILE:
return tmpfs_from_file(t);
case TMPFS_TYPE_DIR:
return tmpfs_from_dir((struct tmpfs_dir *)t);
}
}
}
spin_unlock(&tmpfs_lock);
return NULL;
}
static void unlink_tmpfs(fs_node_t * node, char * name) {
struct tmpfs_dir * d = (struct tmpfs_dir *)node->device;
int i = -1, j = 0;
spin_lock(&tmpfs_lock);
foreach(f, d->files) {
struct tmpfs_file * t = (struct tmpfs_file *)f->value;
if (!strcmp(name, t->name)) {
tmpfs_file_free(t);
free(t);
i = j;
break;
}
j++;
}
if (i >= 0) {
list_remove(d->files, i);
}
spin_unlock(&tmpfs_lock);
return;
}
static void create_tmpfs(fs_node_t *parent, char *name, uint16_t permission) {
if (!name) return;
struct tmpfs_dir * d = (struct tmpfs_dir *)parent->device;
debug_print(CRITICAL, "Creating TMPFS file %s in %s", name, d->name);
spin_lock(&tmpfs_lock);
foreach(f, d->files) {
struct tmpfs_file * t = (struct tmpfs_file *)f->value;
if (!strcmp(name, t->name)) {
spin_unlock(&tmpfs_lock);
debug_print(WARNING, "... already exists.");
return; /* Already exists */
}
}
spin_unlock(&tmpfs_lock);
debug_print(NOTICE, "... creating a new file.");
struct tmpfs_file * t = tmpfs_file_new(name);
t->mask = permission;
t->uid = current_process->user;
t->gid = current_process->user;
spin_lock(&tmpfs_lock);
list_insert(d->files, t);
spin_unlock(&tmpfs_lock);
}
static void mkdir_tmpfs(fs_node_t * parent, char * name, uint16_t permission) {
if (!name) return;
struct tmpfs_dir * d = (struct tmpfs_dir *)parent->device;
debug_print(CRITICAL, "Creating TMPFS directory %s (in %s)", name, d->name);
spin_lock(&tmpfs_lock);
foreach(f, d->files) {
struct tmpfs_file * t = (struct tmpfs_file *)f->value;
if (!strcmp(name, t->name)) {
spin_unlock(&tmpfs_lock);
debug_print(WARNING, "... already exists.");
return; /* Already exists */
}
}
spin_unlock(&tmpfs_lock);
debug_print(NOTICE, "... creating a new directory.");
struct tmpfs_dir * out = tmpfs_dir_new(name, d);
out->mask = permission;
out->uid = current_process->user;
out->gid = current_process->user;
spin_lock(&tmpfs_lock);
list_insert(d->files, out);
spin_unlock(&tmpfs_lock);
}
static fs_node_t * tmpfs_from_dir(struct tmpfs_dir * d) {
fs_node_t * fnode = malloc(sizeof(fs_node_t));
memset(fnode, 0x00, sizeof(fs_node_t));
fnode->inode = 0;
strcpy(fnode->name, "tmp");
fnode->mask = d->mask;
fnode->uid = d->uid;
fnode->gid = d->gid;
fnode->device = d;
fnode->atime = d->atime;
fnode->mtime = d->mtime;
fnode->ctime = d->ctime;
fnode->flags = FS_DIRECTORY;
fnode->read = NULL;
fnode->write = NULL;
fnode->open = NULL;
fnode->close = NULL;
fnode->readdir = readdir_tmpfs;
fnode->finddir = finddir_tmpfs;
fnode->create = create_tmpfs;
fnode->unlink = unlink_tmpfs;
fnode->mkdir = mkdir_tmpfs;
fnode->nlink = 1; /* should be "number of children that are directories + 1" */
return fnode;
}
fs_node_t * tmpfs_create(char * name) {
tmpfs_root = tmpfs_dir_new(name, NULL);
tmpfs_root->mask = 0777;
tmpfs_root->uid = 0;
tmpfs_root->gid = 0;
return tmpfs_from_dir(tmpfs_root);
}
static int tmpfs_initialize(void) {
vfs_mount("/tmp", tmpfs_create("tmp"));
fs_root = tmpfs_create("/");
return 0;
}
static int tmpfs_finalize(void) {
return 0;
}
MODULE_DEF(tmpfs, tmpfs_initialize, tmpfs_finalize);