#include <nxt_main.h>
#if (NXT_HAVE_MEMFD_CREATE)
#include <linux/memfd.h>
#include <unistd.h>
#include <sys/syscall.h>
#endif
#define PORT_MMAP_CHUNK_SIZE (1024 * 16)
#define PORT_MMAP_HEADER_SIZE (1024 * 4)
#define PORT_MMAP_SIZE (PORT_MMAP_HEADER_SIZE + 1024 * 1024 * 10)
#define PORT_MMAP_CHUNK_COUNT \
( (PORT_MMAP_SIZE - PORT_MMAP_HEADER_SIZE) / PORT_MMAP_CHUNK_SIZE )
typedef uint32_t nxt_chunk_id_t;
typedef nxt_atomic_uint_t nxt_free_map_t;
#define FREE_BITS (sizeof(nxt_free_map_t) * 8)
#define FREE_IDX(nchunk) ((nchunk) / FREE_BITS)
#define FREE_MASK(nchunk) \
( 1ULL << ( (nchunk) % FREE_BITS ) )
#define MAX_FREE_IDX FREE_IDX(PORT_MMAP_CHUNK_COUNT)
/* Mapped at the start of shared memory segment. */
struct nxt_port_mmap_header_s {
nxt_free_map_t free_map[MAX_FREE_IDX];
};
/*
* Element of nxt_process_t.incoming/outgoing, shared memory segment
* descriptor.
*/
struct nxt_port_mmap_s {
uint32_t id;
nxt_fd_t fd;
nxt_pid_t pid; /* For sanity check. */
union {
void *mem;
nxt_port_mmap_header_t *hdr;
} u;
};
/* Passed as a second iov chunk when 'mmap' bit in nxt_port_msg_t is 1. */
typedef struct {
uint32_t mmap_id; /* Mmap index in nxt_process_t.outgoing. */
nxt_chunk_id_t chunk_id; /* Mmap chunk index. */
uint32_t size; /* Payload data size. */
} nxt_port_mmap_msg_t;
static nxt_bool_t
nxt_port_mmap_get_free_chunk(nxt_port_mmap_t *port_mmap, nxt_chunk_id_t *c);
#define nxt_port_mmap_get_chunk_busy(hdr, c) \
((hdr->free_map[FREE_IDX(c)] & FREE_MASK(c)) == 0)
nxt_inline void
nxt_port_mmap_set_chunk_busy(nxt_port_mmap_header_t *hdr, nxt_chunk_id_t c);
nxt_inline void
nxt_port_mmap_set_chunk_free(nxt_port_mmap_header_t *hdr, nxt_chunk_id_t c);
#define nxt_port_mmap_chunk_id(port_mmap, b) \
((((u_char *) (b) - (u_char *) (port_mmap->u.mem)) - \
PORT_MMAP_HEADER_SIZE) / PORT_MMAP_CHUNK_SIZE)
#define nxt_port_mmap_chunk_start(port_mmap, chunk) \
(((u_char *) (port_mmap->u.mem)) + PORT_MMAP_HEADER_SIZE + \
(chunk) * PORT_MMAP_CHUNK_SIZE)
void
nxt_port_mmap_destroy(nxt_port_mmap_t *port_mmap)
{
if (port_mmap->u.mem != NULL) {
nxt_mem_munmap(port_mmap->u.mem, PORT_MMAP_SIZE);
port_mmap->u.mem = NULL;
}
if (port_mmap->fd != -1) {
close(port_mmap->fd);
port_mmap->fd = -1;
}
}
static void
nxt_port_mmap_buf_completion(nxt_task_t *task, void *obj, void *data)
{
u_char *p;
nxt_buf_t *b;
nxt_chunk_id_t c;
nxt_mem_pool_t *mp;
nxt_port_mmap_t *port_mmap;
nxt_port_mmap_header_t *hdr;
b = obj;
nxt_debug(task, "mmap buf completion: %p %p", b, b->mem.start);
mp = b->data;
port_mmap = (nxt_port_mmap_t *) b->parent;
hdr = port_mmap->u.hdr;
if (b->is_port_mmap_sent && b->mem.pos > b->mem.start) {
/*
* Chunks until b->mem.pos has been sent to other side,
* let's release rest (if any).
*/
p = b->mem.pos - 1;
c = nxt_port_mmap_chunk_id(port_mmap, p) + 1;
p = nxt_port_mmap_chunk_start(port_mmap, c);
} else {
p = b->mem.start;
c = nxt_port_mmap_chunk_id(port_mmap, p);
}
while (p < b->mem.end) {
nxt_port_mmap_set_chunk_free(hdr, c);
p += PORT_MMAP_CHUNK_SIZE;
c++;
}
nxt_buf_free(mp, b);
}
static nxt_bool_t
nxt_port_mmap_get_free_chunk(nxt_port_mmap_t *port_mmap, nxt_chunk_id_t *c)
{
int ffs;
size_t i;
nxt_free_map_t bits;
nxt_free_map_t *free_map;
free_map = port_mmap->u.hdr->free_map;
for (i = 0; i < MAX_FREE_IDX; i++) {
bits = free_map[i];
if (bits == 0) {
continue;
}
ffs = __builtin_ffsll(bits);
if (ffs != 0) {
*c = i * FREE_BITS + ffs - 1;
return 1;
}
}
return 0;
}
nxt_inline void
nxt_port_mmap_set_chunk_busy(nxt_port_mmap_header_t *hdr, nxt_chunk_id_t c)
{
nxt_atomic_and_fetch(hdr->free_map + FREE_IDX(c), ~FREE_MASK(c));
nxt_thread_log_debug("set_chunk_busy: hdr %p; b %D", hdr, c);
}
nxt_inline void
nxt_port_mmap_set_chunk_free(nxt_port_mmap_header_t *hdr, nxt_chunk_id_t c)
{
nxt_atomic_or_fetch(hdr->free_map + FREE_IDX(c), FREE_MASK(c));
nxt_thread_log_debug("set_chunk_free: hdr %p; b %D", hdr, c);
}
nxt_port_mmap_t *
nxt_port_incoming_port_mmap(nxt_task_t *task, nxt_process_t *process,
nxt_fd_t fd)
{
struct stat mmap_stat;
nxt_port_mmap_t *port_mmap;
nxt_debug(task, "got new mmap fd #%FD from process %PI",
fd, process->pid);
if (fstat(fd, &mmap_stat) == -1) {
nxt_log(task, NXT_LOG_WARN, "fstat(%FD) failed %E", fd, nxt_errno);
return NULL;
}
if (process->incoming == NULL) {
process->incoming = nxt_array_create(process->mem_pool, 1,
sizeof(nxt_port_mmap_t));
}
if (nxt_slow_path(process->incoming == NULL)) {
nxt_log(task, NXT_LOG_WARN, "failed to allocate incoming array");
return NULL;
}
port_mmap = nxt_array_zero_add(process->incoming);
if (nxt_slow_path(port_mmap == NULL)) {
nxt_log(task, NXT_LOG_WARN, "failed to add mmap to incoming array");
return NULL;
}
port_mmap->id = process->incoming->nelts - 1;
port_mmap->fd = -1;
port_mmap->pid = process->pid;
port_mmap->u.mem = nxt_mem_mmap(NULL, mmap_stat.st_size,
PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
if (nxt_slow_path(port_mmap->u.mem == MAP_FAILED)) {
nxt_log(task, NXT_LOG_WARN, "mmap() failed %E", nxt_errno);
port_mmap->u.mem = NULL;
return NULL;
}
return port_mmap;
}
static void
nxt_port_mmap_send_fd_buf_completion(nxt_task_t *task, void *obj, void *data)
{
nxt_buf_t *b;
nxt_port_t *port;
nxt_port_mmap_t *port_mmap;
b = obj;
port = b->data;
port_mmap = (nxt_port_mmap_t *) b->parent;
nxt_debug(task, "mmap fd %FD sent to %PI", port_mmap->fd, port->pid);
close(port_mmap->fd);
port_mmap->fd = -1;
nxt_buf_free(port->mem_pool, b);
}
static nxt_port_mmap_t *
nxt_port_new_port_mmap(nxt_task_t *task, nxt_process_t *process,
nxt_port_t *port)
{
u_char *p, name[64];
nxt_buf_t *b;
nxt_port_mmap_t *port_mmap;
nxt_port_mmap_header_t *hdr;
if (process->outgoing == NULL) {
process->outgoing = nxt_array_create(process->mem_pool, 1,
sizeof(nxt_port_mmap_t));
}
if (nxt_slow_path(process->outgoing == NULL)) {
nxt_log(task, NXT_LOG_WARN, "failed to allocate outgoing array");
return NULL;
}
port_mmap = nxt_array_zero_add(process->outgoing);
if (nxt_slow_path(port_mmap == NULL)) {
nxt_log(task, NXT_LOG_WARN,
"failed to add port mmap to outgoing array");
return NULL;
}
port_mmap->id = process->outgoing->nelts - 1;
port_mmap->pid = process->pid;
p = nxt_sprintf(name, name + sizeof(name), "/nginext.%PI.%PT.%D",
nxt_pid, task->thread->tid, nxt_random(&nxt_random_data));
*p = '\0';
#if (NXT_HAVE_MEMFD_CREATE)
port_mmap->fd = syscall(SYS_memfd_create, name, MFD_CLOEXEC);
if (nxt_slow_path(port_mmap->fd == -1)) {
nxt_log(task, NXT_LOG_CRIT, "memfd_create(%s) failed %E",
name, nxt_errno);
goto remove_fail;
}
nxt_debug(task, "memfd_create(%s): %FD", name, port_mmap->fd);
#elif (NXT_HAVE_SHM_OPEN)
shm_unlink((char *) name); // just in case
port_mmap->fd = shm_open((char *) name, O_CREAT | O_EXCL | O_RDWR,
S_IRUSR | S_IWUSR);
nxt_debug(task, "shm_open(%s): %FD", name, port_mmap->fd);
if (nxt_slow_path(port_mmap->fd == -1)) {
nxt_log(task, NXT_LOG_CRIT, "shm_open(%s) failed %E", name, nxt_errno);
goto remove_fail;
}
if (nxt_slow_path(shm_unlink((char *) name) == -1)) {
nxt_log(task, NXT_LOG_WARN, "shm_unlink(%s) failed %E", name,
nxt_errno);
}
#endif
if (nxt_slow_path(ftruncate(port_mmap->fd, PORT_MMAP_SIZE) == -1)) {
nxt_log(task, NXT_LOG_WARN, "ftruncate() failed %E", nxt_errno);
goto remove_fail;
}
port_mmap->u.mem = nxt_mem_mmap(NULL, PORT_MMAP_SIZE,
PROT_READ | PROT_WRITE, MAP_SHARED,
port_mmap->fd, 0);
if (nxt_slow_path(port_mmap->u.mem == MAP_FAILED)) {
goto remove_fail;
}
/* Init segment header. */
hdr = port_mmap->u.hdr;
nxt_memset(hdr->free_map, 0xFFU, sizeof(hdr->free_map));
/* Mark as busy chunk followed the last available chunk. */
nxt_port_mmap_set_chunk_busy(hdr, PORT_MMAP_CHUNK_COUNT);
nxt_debug(task, "send mmap fd %FD to process %PI", port_mmap->fd,
port->pid);
b = nxt_buf_mem_alloc(port->mem_pool, 0, 0);
b->completion_handler = nxt_port_mmap_send_fd_buf_completion;
b->data = port;
b->parent = port_mmap;
/* TODO handle error */
(void) nxt_port_socket_write(task, port, NXT_PORT_MSG_MMAP, port_mmap->fd,
0, 0, b);
nxt_log(task, NXT_LOG_DEBUG, "new mmap #%D created for %PI -> %PI",
port_mmap->id, nxt_pid, process->pid);
return port_mmap;
remove_fail:
nxt_array_remove(process->outgoing, port_mmap);
return NULL;
}
static nxt_port_mmap_t *
nxt_port_mmap_get(nxt_task_t *task, nxt_port_t *port, nxt_chunk_id_t *c,
size_t size)
{
nxt_array_t *outgoing;
nxt_process_t *process;
nxt_port_mmap_t *port_mmap;
nxt_port_mmap_t *end_port_mmap;
process = nxt_runtime_process_get(task->thread->runtime, port->pid);
if (nxt_slow_path(process == NULL)) {
return NULL;
}
*c = 0;
if (process->outgoing == NULL) {
return nxt_port_new_port_mmap(task, process, port);
}
outgoing = process->outgoing;
port_mmap = outgoing->elts;
end_port_mmap = port_mmap + outgoing->nelts;
while (port_mmap < end_port_mmap) {
if (nxt_port_mmap_get_free_chunk(port_mmap, c)) {
return port_mmap;
}
port_mmap++;
}
/* TODO introduce port_mmap limit and release wait. */
return nxt_port_new_port_mmap(task, process, port);
}
static nxt_port_mmap_t *
nxt_port_get_port_incoming_mmap(nxt_task_t *task, nxt_pid_t spid, uint32_t id)
{
nxt_array_t *incoming;
nxt_process_t *process;
nxt_port_mmap_t *port_mmap;
process = nxt_runtime_process_get(task->thread->runtime, spid);
if (nxt_slow_path(process == NULL)) {
return NULL;
}
incoming = process->incoming;
if (nxt_slow_path(incoming == NULL)) {
/* TODO add warning */
return NULL;
}
if (nxt_slow_path(incoming->nelts <= id)) {
/* TODO add warning */
return NULL;
}
port_mmap = incoming->elts;
return port_mmap + id;
}
nxt_buf_t *
nxt_port_mmap_get_buf(nxt_task_t *task, nxt_port_t *port, size_t size)
{
size_t nchunks;
nxt_buf_t *b;
nxt_chunk_id_t c;
nxt_port_mmap_t *port_mmap;
nxt_port_mmap_header_t *hdr;
nxt_debug(task, "request %z bytes shm buffer", size);
b = nxt_mem_cache_zalloc0(port->mem_pool, NXT_BUF_PORT_MMAP_SIZE);
if (nxt_slow_path(b == NULL)) {
return NULL;
}
b->data = port->mem_pool;
b->completion_handler = nxt_port_mmap_buf_completion;
b->size = NXT_BUF_PORT_MMAP_SIZE;
nxt_buf_set_port_mmap(b);
port_mmap = nxt_port_mmap_get(task, port, &c, size);
if (nxt_slow_path(port_mmap == NULL)) {
nxt_buf_free(port->mem_pool, b);
return NULL;
}
hdr = port_mmap->u.hdr;
b->parent = port_mmap;
b->mem.start = nxt_port_mmap_chunk_start(port_mmap, c);
b->mem.pos = b->mem.start;
b->mem.free = b->mem.start;
b->mem.end = b->mem.start + PORT_MMAP_CHUNK_SIZE;
nxt_port_mmap_set_chunk_busy(hdr, c);
nchunks = size / PORT_MMAP_CHUNK_SIZE;
if ((size % PORT_MMAP_CHUNK_SIZE) != 0 || nchunks == 0) {
nchunks++;
}
c++;
nchunks--;
/* Try to acquire as much chunks as required. */
while (nchunks > 0) {
if (nxt_port_mmap_get_chunk_busy(hdr, c)) {
break;
}
nxt_port_mmap_set_chunk_busy(hdr, c);
b->mem.end += PORT_MMAP_CHUNK_SIZE;
c++;
nchunks--;
}
return b;
}
static nxt_buf_t *
nxt_port_mmap_get_incoming_buf(nxt_task_t *task, nxt_port_t *port,
nxt_pid_t spid, nxt_port_mmap_msg_t *mmap_msg)
{
size_t nchunks;
nxt_buf_t *b;
nxt_port_mmap_t *port_mmap;
b = nxt_mem_cache_zalloc0(port->mem_pool, NXT_BUF_PORT_MMAP_SIZE);
if (nxt_slow_path(b == NULL)) {
return NULL;
}
b->data = port->mem_pool;
b->completion_handler = nxt_port_mmap_buf_completion;
b->size = NXT_BUF_PORT_MMAP_SIZE;
nxt_buf_set_port_mmap(b);
port_mmap = nxt_port_get_port_incoming_mmap(task, spid, mmap_msg->mmap_id);
if (nxt_slow_path(port_mmap == NULL)) {
nxt_buf_free(port->mem_pool, b);
return NULL;
}
nchunks = mmap_msg->size / PORT_MMAP_CHUNK_SIZE;
if ((mmap_msg->size % PORT_MMAP_CHUNK_SIZE) != 0) {
nchunks++;
}
b->mem.start = nxt_port_mmap_chunk_start(port_mmap, mmap_msg->chunk_id);
b->mem.pos = b->mem.start;
b->mem.free = b->mem.start + mmap_msg->size;
b->mem.end = b->mem.start + nchunks * PORT_MMAP_CHUNK_SIZE;
b->parent = port_mmap;
return b;
}
void
nxt_port_mmap_write(nxt_task_t *task, nxt_port_t *port,
nxt_port_send_msg_t *msg, nxt_sendbuf_coalesce_t *sb)
{
size_t bsize;
nxt_buf_t *b, *bmem;
nxt_uint_t i;
nxt_port_mmap_t *port_mmap;
nxt_port_mmap_msg_t *mmap_msg;
nxt_debug(task, "prepare %z bytes message for transfer to process %PI "
"via shared memory", sb->size, port->pid);
bsize = sb->niov * sizeof(nxt_port_mmap_msg_t);
b = nxt_buf_mem_alloc(port->mem_pool, bsize, 0);
if (nxt_slow_path(b == NULL)) {
return;
}
mmap_msg = (nxt_port_mmap_msg_t *) b->mem.start;
bmem = msg->buf;
for (i = 0; i < sb->niov; i++, mmap_msg++) {
/* Lookup buffer which starts current iov_base. */
while (bmem && sb->iobuf[i].iov_base != bmem->mem.pos) {
bmem = bmem->next;
}
if (nxt_slow_path(bmem == NULL)) {
nxt_log_error(NXT_LOG_ERR, task->log, "failed to find buf for "
"iobuf[%d]", i);
return;
/* TODO clear b and exit */
}
port_mmap = (nxt_port_mmap_t *) bmem->parent;
mmap_msg->mmap_id = port_mmap->id;
mmap_msg->chunk_id = nxt_port_mmap_chunk_id(port_mmap, bmem->mem.pos);
mmap_msg->size = sb->iobuf[i].iov_len;
nxt_debug(task, "mmap_msg={%D, %D, %D} to %PI",
mmap_msg->mmap_id, mmap_msg->chunk_id, mmap_msg->size,
port->pid);
}
msg->buf = b;
b->mem.free += bsize;
sb->iobuf[0].iov_base = b->mem.pos;
sb->iobuf[0].iov_len = bsize;
sb->niov = 1;
sb->size = bsize;
msg->port_msg.mmap = 1;
}
void
nxt_port_mmap_read(nxt_task_t *task, nxt_port_t *port,
nxt_port_recv_msg_t *msg, size_t size)
{
nxt_buf_t *b, **pb;
nxt_port_mmap_msg_t *end, *mmap_msg;
b = msg->buf;
mmap_msg = (nxt_port_mmap_msg_t *) b->mem.pos;
end = (nxt_port_mmap_msg_t *) b->mem.free;
pb = &msg->buf;
while (mmap_msg < end) {
nxt_debug(task, "mmap_msg={%D, %D, %D} from %PI",
mmap_msg->mmap_id, mmap_msg->chunk_id, mmap_msg->size,
msg->port_msg.pid);
*pb = nxt_port_mmap_get_incoming_buf(task, port, msg->port_msg.pid,
mmap_msg);
if (nxt_slow_path(*pb == NULL)) {
nxt_log_error(NXT_LOG_ERR, task->log, "failed to get mmap buffer");
break;
}
pb = &(*pb)->next;
mmap_msg++;
}
/* Mark original buf as complete. */
b->mem.pos += nxt_buf_used_size(b);
}
nxt_port_method_t
nxt_port_mmap_get_method(nxt_task_t *task, nxt_port_t *port, nxt_buf_t *b)
{
nxt_port_mmap_t *port_mmap;
nxt_port_method_t m;
m = NXT_PORT_METHOD_ANY;
for (; b != NULL; b = b->next) {
if (nxt_buf_used_size(b) == 0) {
/* empty buffers does not affect method */
continue;
}
if (nxt_buf_is_port_mmap(b)) {
port_mmap = (nxt_port_mmap_t *) b->parent;
if (m == NXT_PORT_METHOD_PLAIN) {
nxt_log_error(NXT_LOG_ERR, task->log,
"mixing plain and mmap buffers, "
"using plain mode");
break;
}
if (port->pid != port_mmap->pid) {
nxt_log_error(NXT_LOG_ERR, task->log,
"send mmap buffer for %PI to %PI, "
"using plain mode", port_mmap->pid, port->pid);
m = NXT_PORT_METHOD_PLAIN;
break;
}
if (m == NXT_PORT_METHOD_ANY) {
nxt_debug(task, "using mmap mode");
m = NXT_PORT_METHOD_MMAP;
}
} else {
if (m == NXT_PORT_METHOD_MMAP) {
nxt_log_error(NXT_LOG_ERR, task->log,
"mixing mmap and plain buffers, "
"switching to plain mode");
m = NXT_PORT_METHOD_PLAIN;
break;
}
if (m == NXT_PORT_METHOD_ANY) {
nxt_debug(task, "using plain mode");
m = NXT_PORT_METHOD_PLAIN;
}
}
}
return m;
}