#include "bus-kernel.h"
#include "bus-bloom.h"
-#define KDBUS_ITEM_NEXT(item) \
- (typeof(item))(((uint8_t *)item) + ALIGN8((item)->size))
-
-#define KDBUS_ITEM_FOREACH(item, head) \
- for (item = (head)->items; \
- (uint8_t *)(item) < (uint8_t *)(head) + (head)->size; \
- item = KDBUS_ITEM_NEXT(item))
-
-#define KDBUS_ITEM_HEADER_SIZE offsetof(struct kdbus_item, data)
-#define KDBUS_ITEM_SIZE(s) ALIGN8((s) + KDBUS_ITEM_HEADER_SIZE)
-
-#define KDBUS_POOL_SIZE (4*1024*1024)
-
-static int parse_unique_name(const char *s, uint64_t *id) {
+int bus_kernel_parse_unique_name(const char *s, uint64_t *id) {
int r;
assert(s);
static void append_payload_vec(struct kdbus_item **d, const void *p, size_t sz) {
assert(d);
- assert(p);
assert(sz > 0);
*d = ALIGN8_PTR(*d);
+ /* Note that p can be NULL, which encodes a region full of
+ * zeroes, which is useful to optimize certain padding
+ * conditions */
+
(*d)->size = offsetof(struct kdbus_item, vec) + sizeof(struct kdbus_vec);
(*d)->type = KDBUS_MSG_PAYLOAD_VEC;
- (*d)->vec.address = (intptr_t) p;
+ (*d)->vec.address = PTR_TO_UINT64(p);
(*d)->vec.size = sz;
*d = (struct kdbus_item *) ((uint8_t*) *d + (*d)->size);
}
+static void append_payload_memfd(struct kdbus_item **d, int memfd, size_t sz) {
+ assert(d);
+ assert(memfd >= 0);
+ assert(sz > 0);
+
+ *d = ALIGN8_PTR(*d);
+ (*d)->size = offsetof(struct kdbus_item, memfd) + sizeof(struct kdbus_memfd);
+ (*d)->type = KDBUS_MSG_PAYLOAD_MEMFD;
+ (*d)->memfd.fd = memfd;
+ (*d)->memfd.size = sz;
+
+ *d = (struct kdbus_item *) ((uint8_t*) *d + (*d)->size);
+}
+
static void append_destination(struct kdbus_item **d, const char *s, size_t length) {
assert(d);
assert(s);
bloom_add_pair(bloom, "member", m->member);
if (m->path) {
bloom_add_pair(bloom, "path", m->path);
+ bloom_add_pair(bloom, "path-slash-prefix", m->path);
bloom_add_prefixes(bloom, "path-slash-prefix", m->path, '/');
}
}
static int bus_message_setup_kmsg(sd_bus *b, sd_bus_message *m) {
+ struct bus_body_part *part;
struct kdbus_item *d;
bool well_known;
uint64_t unique;
size_t sz, dl;
+ unsigned i;
int r;
assert(b);
return 0;
if (m->destination) {
- r = parse_unique_name(m->destination, &unique);
+ r = bus_kernel_parse_unique_name(m->destination, &unique);
if (r < 0)
return r;
sz = offsetof(struct kdbus_msg, items);
+ assert_cc(ALIGN8(offsetof(struct kdbus_item, vec) + sizeof(struct kdbus_vec)) ==
+ ALIGN8(offsetof(struct kdbus_item, memfd) + sizeof(struct kdbus_memfd)));
+
/* Add in fixed header, fields header and payload */
- sz += 3 * ALIGN8(offsetof(struct kdbus_item, vec) + sizeof(struct kdbus_vec));
+ sz += (1 + m->n_body_parts) *
+ ALIGN8(offsetof(struct kdbus_item, vec) + sizeof(struct kdbus_vec));
/* Add space for bloom filter */
sz += ALIGN8(offsetof(struct kdbus_item, data) + BLOOM_SIZE);
sz += ALIGN8(offsetof(struct kdbus_item, fds) + sizeof(int)*m->n_fds);
m->kdbus = memalign(8, sz);
- if (!m->kdbus)
- return -ENOMEM;
+ if (!m->kdbus) {
+ r = -ENOMEM;
+ goto fail;
+ }
+ m->free_kdbus = true;
memset(m->kdbus, 0, sz);
m->kdbus->flags =
if (well_known)
append_destination(&d, m->destination, dl);
- append_payload_vec(&d, m->header, sizeof(*m->header));
+ append_payload_vec(&d, m->header, BUS_MESSAGE_BODY_BEGIN(m));
- if (m->fields)
- append_payload_vec(&d, m->fields, ALIGN8(m->header->fields_size));
+ MESSAGE_FOREACH_PART(part, i, m) {
+ if (part->is_zero) {
+ /* If this is padding then simply send a
+ * vector with a NULL data pointer which the
+ * kernel will just pass through. This is the
+ * most efficient way to encode zeroes */
- if (m->body)
- append_payload_vec(&d, m->body, m->header->body_size);
+ append_payload_vec(&d, NULL, part->size);
+ continue;
+ }
+
+ if (part->memfd >= 0 && part->sealed && m->destination) {
+ /* Try to send a memfd, if the part is
+ * sealed and this is not a broadcast. Since we can only */
+
+ append_payload_memfd(&d, part->memfd, part->size);
+ continue;
+ }
+
+ /* Otherwise let's send a vector to the actual data,
+ * for that we need to map it first. */
+ r = bus_body_part_map(part);
+ if (r < 0)
+ goto fail;
+
+ append_payload_vec(&d, part->data, part->size);
+ }
if (m->kdbus->dst_id == KDBUS_DST_ID_BROADCAST) {
void *p;
p = append_bloom(&d, BLOOM_SIZE);
r = bus_message_setup_bloom(m, p);
- if (r < 0) {
- free(m->kdbus);
- m->kdbus = NULL;
- return -r;
- }
+ if (r < 0)
+ goto fail;
}
if (m->n_fds > 0)
m->kdbus->size = (uint8_t*) d - (uint8_t*) m->kdbus;
assert(m->kdbus->size <= sz);
- m->free_kdbus = true;
-
return 0;
+
+fail:
+ m->poisoned = true;
+ return r;
}
int bus_kernel_take_fd(sd_bus *b) {
- uint8_t h[ALIGN8(sizeof(struct kdbus_cmd_hello)) +
- ALIGN8(KDBUS_ITEM_HEADER_SIZE) +
- ALIGN8(sizeof(struct kdbus_vec))] = {};
-
- struct kdbus_cmd_hello *hello = (struct kdbus_cmd_hello*) h;
-
+ struct kdbus_cmd_hello hello;
int r;
assert(b);
if (b->is_server)
return -EINVAL;
+ b->use_memfd = 1;
+
+ zero(hello);
+ hello.size = sizeof(hello);
+ hello.conn_flags = b->hello_flags;
+ hello.pool_size = KDBUS_POOL_SIZE;
+
+ r = ioctl(b->input_fd, KDBUS_CMD_HELLO, &hello);
+ if (r < 0)
+ return -errno;
+
if (!b->kdbus_buffer) {
- b->kdbus_buffer = mmap(NULL, KDBUS_POOL_SIZE, PROT_READ|PROT_WRITE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
+ b->kdbus_buffer = mmap(NULL, KDBUS_POOL_SIZE, PROT_READ, MAP_SHARED, b->input_fd, 0);
if (b->kdbus_buffer == MAP_FAILED) {
b->kdbus_buffer = NULL;
return -errno;
}
}
- hello->size = sizeof(h);
- hello->conn_flags =
- KDBUS_HELLO_ACCEPT_FD|
- KDBUS_HELLO_ATTACH_COMM|
- KDBUS_HELLO_ATTACH_EXE|
- KDBUS_HELLO_ATTACH_CMDLINE|
- KDBUS_HELLO_ATTACH_CGROUP|
- KDBUS_HELLO_ATTACH_CAPS|
- KDBUS_HELLO_ATTACH_SECLABEL|
- KDBUS_HELLO_ATTACH_AUDIT;
-
- hello->items[0].type = KDBUS_HELLO_POOL;
- hello->items[0].size = KDBUS_ITEM_HEADER_SIZE + sizeof(struct kdbus_vec);
- hello->items[0].vec.address = (uint64_t) b->kdbus_buffer;
- hello->items[0].vec.size = KDBUS_POOL_SIZE;
-
- r = ioctl(b->input_fd, KDBUS_CMD_HELLO, hello);
- if (r < 0)
- return -errno;
-
/* The higher 32bit of both flags fields are considered
* 'incompatible flags'. Refuse them all for now. */
- if (hello->bus_flags > 0xFFFFFFFFULL ||
- hello->conn_flags > 0xFFFFFFFFULL)
+ if (hello.bus_flags > 0xFFFFFFFFULL ||
+ hello.conn_flags > 0xFFFFFFFFULL)
return -ENOTSUP;
- if (hello->bloom_size != BLOOM_SIZE)
+ if (hello.bloom_size != BLOOM_SIZE)
return -ENOTSUP;
- if (asprintf(&b->unique_name, ":1.%llu", (unsigned long long) hello->id) < 0)
+ if (asprintf(&b->unique_name, ":1.%llu", (unsigned long long) hello.id) < 0)
return -ENOMEM;
b->is_kernel = true;
b->bus_client = true;
- b->can_fds = true;
+ b->can_fds = !!(hello.conn_flags & KDBUS_HELLO_ACCEPT_FD);
r = bus_start_running(b);
if (r < 0)
}
static void close_kdbus_msg(sd_bus *bus, struct kdbus_msg *k) {
+ uint64_t off;
struct kdbus_item *d;
assert(bus);
assert(k);
- ioctl(bus->input_fd, KDBUS_CMD_MSG_RELEASE, k);
+ off = (uint8_t *)k - (uint8_t *)bus->kdbus_buffer;
+ ioctl(bus->input_fd, KDBUS_CMD_MSG_RELEASE, &off);
KDBUS_ITEM_FOREACH(d, k) {
- if (d->type != KDBUS_MSG_FDS)
- continue;
-
- close_many(d->fds, (d->size - offsetof(struct kdbus_item, fds)) / sizeof(int));
+ if (d->type == KDBUS_MSG_FDS)
+ close_many(d->fds, (d->size - offsetof(struct kdbus_item, fds)) / sizeof(int));
+ else if (d->type == KDBUS_MSG_PAYLOAD_MEMFD)
+ close_nointr_nofail(d->memfd.fd);
}
}
-static bool range_contains(size_t astart, size_t asize, size_t bstart, size_t bsize, void *a, void **b) {
-
- if (bstart < astart)
- return false;
-
- if (bstart + bsize > astart + asize)
- return false;
-
- *b = (uint8_t*) a + (bstart - astart);
-
- return true;
-}
-
static int bus_kernel_make_message(sd_bus *bus, struct kdbus_msg *k, sd_bus_message **ret) {
sd_bus_message *m = NULL;
struct kdbus_item *d;
- unsigned n_payload = 0, n_fds = 0;
+ unsigned n_fds = 0;
_cleanup_free_ int *fds = NULL;
struct bus_header *h = NULL;
size_t total, n_bytes = 0, idx = 0;
l = d->size - offsetof(struct kdbus_item, data);
- if (d->type == KDBUS_MSG_PAYLOAD_VEC) {
+ if (d->type == KDBUS_MSG_PAYLOAD_OFF) {
if (!h) {
- if (d->vec.size < sizeof(struct bus_header))
- return -EBADMSG;
+ h = (struct bus_header *)((uint8_t *)bus->kdbus_buffer + d->vec.offset);
- h = (struct bus_header*) d->vec.address;
+ if (!bus_header_is_complete(h, d->vec.size))
+ return -EBADMSG;
}
- n_payload++;
n_bytes += d->vec.size;
+ } else if (d->type == KDBUS_MSG_PAYLOAD_MEMFD) {
+
+ if (!h)
+ return -EBADMSG;
+
+ n_bytes += d->memfd.size;
+
} else if (d->type == KDBUS_MSG_FDS) {
int *f;
unsigned j;
memcpy(fds + n_fds, d->fds, sizeof(int) * j);
n_fds += j;
- } else if (d->type == KDBUS_MSG_DST_NAME)
- destination = d->str;
- else if (d->type == KDBUS_MSG_SRC_SECLABEL)
+ } else if (d->type == KDBUS_MSG_SRC_SECLABEL)
seclabel = d->str;
}
if (!h)
return -EBADMSG;
- r = bus_header_size(h, &total);
+ r = bus_header_message_size(h, &total);
if (r < 0)
return r;
if (n_bytes != total)
return -EBADMSG;
- if (n_payload > 2)
- return -EBADMSG;
-
- r = bus_message_from_header(h, sizeof(struct bus_header), fds, n_fds, NULL, seclabel, 0, &m);
+ r = bus_message_from_header(bus, h, sizeof(struct bus_header), fds, n_fds, NULL, seclabel, 0, &m);
if (r < 0)
return r;
l = d->size - offsetof(struct kdbus_item, data);
- if (d->type == KDBUS_MSG_PAYLOAD_VEC) {
+ if (d->type == KDBUS_MSG_PAYLOAD_OFF) {
+ size_t begin_body;
+
+ begin_body = BUS_MESSAGE_BODY_BEGIN(m);
+
+ if (idx + d->vec.size > begin_body) {
+ struct bus_body_part *part;
+
+ /* Contains body material */
+
+ part = message_append_part(m);
+ if (!part) {
+ r = -ENOMEM;
+ goto fail;
+ }
- range_contains(idx, d->vec.size, ALIGN8(sizeof(struct bus_header)), BUS_MESSAGE_FIELDS_SIZE(m), (void*) d->vec.address, &m->fields);
- range_contains(idx, d->vec.size, ALIGN8(sizeof(struct bus_header)) + ALIGN8(BUS_MESSAGE_FIELDS_SIZE(m)), BUS_MESSAGE_BODY_SIZE(m), (void*) d->vec.address, &m->body);
+ /* A -1 offset is NUL padding. */
+ part->is_zero = d->vec.offset == ~0ULL;
+
+ if (idx >= begin_body) {
+ if (!part->is_zero)
+ part->data = (uint8_t *)bus->kdbus_buffer + d->vec.offset;
+ part->size = d->vec.size;
+ } else {
+ if (!part->is_zero)
+ part->data = (uint8_t *)bus->kdbus_buffer + d->vec.offset + (begin_body - idx);
+ part->size = d->vec.size - (begin_body - idx);
+ }
+
+ part->sealed = true;
+ }
idx += d->vec.size;
+ } else if (d->type == KDBUS_MSG_PAYLOAD_MEMFD) {
+ struct bus_body_part *part;
+
+ if (idx < BUS_MESSAGE_BODY_BEGIN(m)) {
+ r = -EBADMSG;
+ goto fail;
+ }
+
+ part = message_append_part(m);
+ if (!part) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ part->memfd = d->memfd.fd;
+ part->size = d->memfd.size;
+ part->sealed = true;
+
+ idx += d->memfd.size;
} else if (d->type == KDBUS_MSG_SRC_CREDS) {
- m->pid_starttime = d->creds.starttime / NSEC_PER_USEC;
- m->uid = d->creds.uid;
- m->gid = d->creds.gid;
- m->pid = d->creds.pid;
- m->tid = d->creds.tid;
- m->uid_valid = m->gid_valid = true;
+ m->creds.pid_starttime = d->creds.starttime / NSEC_PER_USEC;
+ m->creds.uid = d->creds.uid;
+ m->creds.gid = d->creds.gid;
+ m->creds.pid = d->creds.pid;
+ m->creds.tid = d->creds.tid;
+ m->creds.mask |= (SD_BUS_CREDS_UID|SD_BUS_CREDS_GID|SD_BUS_CREDS_PID|SD_BUS_CREDS_PID_STARTTIME|SD_BUS_CREDS_TID) & bus->creds_mask;
+
} else if (d->type == KDBUS_MSG_TIMESTAMP) {
m->realtime = d->timestamp.realtime_ns / NSEC_PER_USEC;
m->monotonic = d->timestamp.monotonic_ns / NSEC_PER_USEC;
- } else if (d->type == KDBUS_MSG_SRC_PID_COMM)
- m->comm = d->str;
- else if (d->type == KDBUS_MSG_SRC_TID_COMM)
- m->tid_comm = d->str;
- else if (d->type == KDBUS_MSG_SRC_EXE)
- m->exe = d->str;
- else if (d->type == KDBUS_MSG_SRC_CMDLINE) {
- m->cmdline = d->str;
- m->cmdline_length = l;
- } else if (d->type == KDBUS_MSG_SRC_CGROUP)
- m->cgroup = d->str;
- else if (d->type == KDBUS_MSG_SRC_AUDIT)
- m->audit = &d->audit;
- else if (d->type == KDBUS_MSG_SRC_CAPS) {
- m->capability = d->data;
- m->capability_size = l;
- } else if (d->type != KDBUS_MSG_FDS &&
- d->type != KDBUS_MSG_DST_NAME &&
+
+ } else if (d->type == KDBUS_MSG_SRC_PID_COMM) {
+ m->creds.comm = d->str;
+ m->creds.mask |= SD_BUS_CREDS_COMM & bus->creds_mask;
+
+ } else if (d->type == KDBUS_MSG_SRC_TID_COMM) {
+ m->creds.tid_comm = d->str;
+ m->creds.mask |= SD_BUS_CREDS_TID_COMM & bus->creds_mask;
+
+ } else if (d->type == KDBUS_MSG_SRC_EXE) {
+ m->creds.exe = d->str;
+ m->creds.mask |= SD_BUS_CREDS_EXE & bus->creds_mask;
+
+ } else if (d->type == KDBUS_MSG_SRC_CMDLINE) {
+ m->creds.cmdline = d->str;
+ m->creds.cmdline_length = l;
+ m->creds.mask |= SD_BUS_CREDS_CMDLINE & bus->creds_mask;
+
+ } else if (d->type == KDBUS_MSG_SRC_CGROUP) {
+ m->creds.cgroup = d->str;
+ m->creds.mask |= (SD_BUS_CREDS_CGROUP|SD_BUS_CREDS_UNIT|SD_BUS_CREDS_USER_UNIT|SD_BUS_CREDS_SLICE|SD_BUS_CREDS_SESSION|SD_BUS_CREDS_OWNER_UID) & bus->creds_mask;
+
+ } else if (d->type == KDBUS_MSG_SRC_AUDIT) {
+ m->creds.audit_session_id = d->audit.sessionid;
+ m->creds.audit_login_uid = d->audit.loginuid;
+ m->creds.mask |= (SD_BUS_CREDS_AUDIT_SESSION_ID|SD_BUS_CREDS_AUDIT_LOGIN_UID) & bus->creds_mask;
+
+ } else if (d->type == KDBUS_MSG_SRC_CAPS) {
+ m->creds.capability = d->data;
+ m->creds.capability_size = l;
+ m->creds.mask |= (SD_BUS_CREDS_EFFECTIVE_CAPS|SD_BUS_CREDS_PERMITTED_CAPS|SD_BUS_CREDS_INHERITABLE_CAPS|SD_BUS_CREDS_BOUNDING_CAPS) & bus->creds_mask;
+
+ } else if (d->type == KDBUS_MSG_DST_NAME)
+ destination = d->str;
+ else if (d->type != KDBUS_MSG_FDS &&
d->type != KDBUS_MSG_SRC_SECLABEL)
log_debug("Got unknown field from kernel %llu", d->type);
}
- if ((BUS_MESSAGE_FIELDS_SIZE(m) > 0 && !m->fields) ||
- (BUS_MESSAGE_BODY_SIZE(m) > 0 && !m->body)) {
- sd_bus_message_unref(m);
- return -EBADMSG;
- }
-
r = bus_message_parse_fields(m);
- if (r < 0) {
- sd_bus_message_unref(m);
- return r;
- }
+ if (r < 0)
+ goto fail;
if (k->src_id == KDBUS_SRC_ID_KERNEL)
m->sender = "org.freedesktop.DBus";
/* We take possession of the kmsg struct now */
m->kdbus = k;
- m->bus = sd_bus_ref(bus);
m->release_kdbus = true;
m->free_fds = true;
*ret = m;
return 1;
+
+fail:
+ if (m) {
+ struct bus_body_part *part;
+ unsigned i;
+
+ /* Make sure the memfds are not freed twice */
+ MESSAGE_FOREACH_PART(part, i, m)
+ if (part->memfd >= 0)
+ part->memfd = -1;
+
+ sd_bus_message_unref(m);
+ }
+
+ return r;
}
int bus_kernel_read_message(sd_bus *bus, sd_bus_message **m) {
+ uint64_t off;
struct kdbus_msg *k;
int r;
assert(bus);
assert(m);
- r = ioctl(bus->input_fd, KDBUS_CMD_MSG_RECV, &k);
+ r = ioctl(bus->input_fd, KDBUS_CMD_MSG_RECV, &off);
if (r < 0) {
if (errno == EAGAIN)
return 0;
return -errno;
}
-
-
-/* /\* Let's tell valgrind that there's really no need to */
-/* * initialize this fully. This should be removed again */
-/* * when valgrind learned the kdbus ioctls natively. *\/ */
-/* #ifdef HAVE_VALGRIND_MEMCHECK_H */
-/* VALGRIND_MAKE_MEM_DEFINED(k, sz); */
-/* #endif */
-
+ k = (struct kdbus_msg *)((uint8_t *)bus->kdbus_buffer + off);
r = bus_kernel_make_message(bus, k, m);
if (r <= 0)
int bus_kernel_create(const char *name, char **s) {
struct kdbus_cmd_bus_make *make;
- struct kdbus_item *n, *cg;
+ struct kdbus_item *n;
size_t l;
int fd;
char *p;
KDBUS_ITEM_HEADER_SIZE + sizeof(uint64_t) +
KDBUS_ITEM_HEADER_SIZE + DECIMAL_STR_MAX(uid_t) + 1 + l + 1);
- cg = make->items;
- cg->type = KDBUS_MAKE_CGROUP;
- cg->data64[0] = 1;
- cg->size = KDBUS_ITEM_HEADER_SIZE + sizeof(uint64_t);
-
- n = KDBUS_ITEM_NEXT(cg);
+ n = make->items;
n->type = KDBUS_MAKE_NAME;
sprintf(n->str, "%lu-%s", (unsigned long) getuid(), name);
n->size = KDBUS_ITEM_HEADER_SIZE + strlen(n->str) + 1;
- make->size = offsetof(struct kdbus_cmd_bus_make, items) + cg->size + n->size;
- make->flags = KDBUS_MAKE_ACCESS_WORLD | KDBUS_MAKE_POLICY_OPEN;
+ make->size = offsetof(struct kdbus_cmd_bus_make, items) + n->size;
+ make->flags = KDBUS_MAKE_POLICY_OPEN;
make->bus_flags = 0;
make->bloom_size = BLOOM_SIZE;
assert_cc(BLOOM_SIZE % 8 == 0);
return fd;
}
+
+int bus_kernel_pop_memfd(sd_bus *bus, void **address, size_t *size) {
+ struct memfd_cache *c;
+ int fd;
+
+ assert(address);
+ assert(size);
+
+ if (!bus || !bus->is_kernel)
+ return -ENOTSUP;
+
+ assert_se(pthread_mutex_lock(&bus->memfd_cache_mutex) >= 0);
+
+ if (bus->n_memfd_cache <= 0) {
+ int r;
+
+ assert_se(pthread_mutex_unlock(&bus->memfd_cache_mutex) >= 0);
+
+ r = ioctl(bus->input_fd, KDBUS_CMD_MEMFD_NEW, &fd);
+ if (r < 0)
+ return -errno;
+
+ *address = NULL;
+ *size = 0;
+ return fd;
+ }
+
+ c = &bus->memfd_cache[--bus->n_memfd_cache];
+
+ assert(c->fd >= 0);
+ assert(c->size == 0 || c->address);
+
+ *address = c->address;
+ *size = c->size;
+ fd = c->fd;
+
+ assert_se(pthread_mutex_unlock(&bus->memfd_cache_mutex) >= 0);
+
+ return fd;
+}
+
+static void close_and_munmap(int fd, void *address, size_t size) {
+ if (size > 0)
+ assert_se(munmap(address, PAGE_ALIGN(size)) >= 0);
+
+ close_nointr_nofail(fd);
+}
+
+void bus_kernel_push_memfd(sd_bus *bus, int fd, void *address, size_t size) {
+ struct memfd_cache *c;
+ uint64_t max_sz = PAGE_ALIGN(MEMFD_CACHE_ITEM_SIZE_MAX);
+
+ assert(fd >= 0);
+ assert(size == 0 || address);
+
+ if (!bus || !bus->is_kernel) {
+ close_and_munmap(fd, address, size);
+ return;
+ }
+
+ assert_se(pthread_mutex_lock(&bus->memfd_cache_mutex) >= 0);
+
+ if (bus->n_memfd_cache >= ELEMENTSOF(bus->memfd_cache)) {
+ assert_se(pthread_mutex_unlock(&bus->memfd_cache_mutex) >= 0);
+
+ close_and_munmap(fd, address, size);
+ return;
+ }
+
+ c = &bus->memfd_cache[bus->n_memfd_cache++];
+ c->fd = fd;
+ c->address = address;
+
+ /* If overly long, let's return a bit to the OS */
+ if (size > max_sz) {
+ assert_se(ioctl(fd, KDBUS_CMD_MEMFD_SIZE_SET, &max_sz) >= 0);
+ assert_se(munmap((uint8_t*) address + max_sz, PAGE_ALIGN(size - max_sz)) >= 0);
+ c->size = max_sz;
+ } else
+ c->size = size;
+
+ assert_se(pthread_mutex_unlock(&bus->memfd_cache_mutex) >= 0);
+}
+
+void bus_kernel_flush_memfd(sd_bus *b) {
+ unsigned i;
+
+ assert(b);
+
+ for (i = 0; i < b->n_memfd_cache; i++)
+ close_and_munmap(b->memfd_cache[i].fd, b->memfd_cache[i].address, b->memfd_cache[i].size);
+}
~ianmdlvl / elogind.git / blobdiff