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Diffstat (limited to 'src/lib/shm_du_map.c')
-rw-r--r--src/lib/shm_du_map.c366
1 files changed, 366 insertions, 0 deletions
diff --git a/src/lib/shm_du_map.c b/src/lib/shm_du_map.c
new file mode 100644
index 00000000..dc73077f
--- /dev/null
+++ b/src/lib/shm_du_map.c
@@ -0,0 +1,366 @@
+/*
+ * Ouroboros - Copyright (C) 2016
+ *
+ * Shared memory map for data units
+ *
+ * Dimitri Staessens <dimitri.staessens@intec.ugent.be>
+ * Sander Vrijders <sander.vrijders@intec.ugent.be>
+ *
+ * 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 of the License, 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 <ouroboros/shm_du_map.h>
+#include <pthread.h>
+#include <sys/mman.h>
+#include <fcntl.h>
+#include <malloc.h>
+#include <string.h>
+
+#define SHM_BLOCKS_SIZE (SHM_BLOCKS_IN_MAP * SHM_DU_BUFF_BLOCK_SIZE)
+#define SHM_FILE_SIZE (SHM_BLOCKS_SIZE + 2 * sizeof (size_t) \
+ + sizeof(pthread_mutex_t))
+
+#define get_head_ptr(dum) \
+((struct shm_du_buff *)(dum->shm_base + (*dum->ptr_head * \
+ SHM_DU_BUFF_BLOCK_SIZE)))
+
+#define get_tail_ptr(dum) \
+((struct shm_du_buff *)(dum->shm_base + (*dum->ptr_tail * \
+ SHM_DU_BUFF_BLOCK_SIZE)))
+
+#define block_ptr_to_idx(dum, sdb) \
+ (((uint8_t *)sdb - dum->shm_base) / SHM_DU_BUFF_BLOCK_SIZE)
+
+#define shm_map_used(dum)((*dum->ptr_head + SHM_BLOCKS_IN_MAP - *dum->ptr_tail)\
+ & (SHM_BLOCKS_IN_MAP - 1))
+#define shm_map_free(dum, i)(shm_map_used(dum) + i < SHM_BLOCKS_IN_MAP)
+
+#define MIN(a,b)(a < b ? a : b)
+
+struct shm_du_buff {
+ size_t size;
+ size_t du_head;
+ size_t du_tail;
+};
+
+struct shm_du_map {
+ uint8_t * shm_base; /* start of blocks */
+ size_t * ptr_head; /* start of ringbuffer head */
+ size_t * ptr_tail; /* start of ringbuffer tail */
+ pthread_mutex_t * shm_mutex; /* lock all free space in shm */
+ int fd;
+};
+
+struct shm_du_map * shm_du_map_create()
+{
+ struct shm_du_map * dum;
+ int shm_fd;
+ uint8_t * shm_base;
+ pthread_mutexattr_t attr;
+
+ dum = malloc(sizeof *dum);
+ if (dum == NULL) {
+ LOG_DBGF("Could not allocate struct.");
+ return NULL;
+ }
+
+ shm_fd = shm_open(SHM_DU_MAP_FILENAME, O_CREAT | O_EXCL | O_RDWR, 0666);
+ if (shm_fd == -1) {
+ LOG_DBGF("Failed creating shared memory map.");
+ free(dum);
+ return NULL;
+ }
+
+ if (lseek(shm_fd, SHM_FILE_SIZE - 1, SEEK_SET) < 0) {
+ LOG_DBGF("Failed to extend shared memory map.");
+ free(dum);
+ return NULL;
+ }
+
+ if (write(shm_fd, "", 1) != 1) {
+ LOG_DBGF("Failed to finalise extension of shared memory map.");
+ free(dum);
+ return NULL;
+ }
+
+ shm_base = mmap(NULL,
+ SHM_FILE_SIZE,
+ PROT_READ | PROT_WRITE,
+ MAP_SHARED,
+ shm_fd,
+ 0);
+
+ if (shm_base == MAP_FAILED) {
+ LOG_DBGF("Failed to map shared memory.");
+
+ if (shm_unlink(SHM_DU_MAP_FILENAME) == -1)
+ LOG_DBGF("Failed to remove invalid shm.");
+
+ free(dum);
+ return NULL;
+ }
+
+ dum->shm_base = shm_base;
+ dum->ptr_head = (size_t *)
+ ((uint8_t *) dum->shm_base + SHM_BLOCKS_SIZE);
+ dum->ptr_tail = (size_t *)
+ ((uint8_t *) dum->ptr_head + sizeof(size_t));
+ dum->shm_mutex = (pthread_mutex_t *)
+ ((uint8_t *) dum->ptr_tail + sizeof(size_t));
+
+ pthread_mutexattr_init(&attr);
+ pthread_mutexattr_setpshared(&attr, PTHREAD_PROCESS_SHARED);
+ pthread_mutex_init(dum->shm_mutex, &attr);
+
+ *dum->ptr_head = 0;
+ *dum->ptr_tail = 0;
+
+ dum->fd = shm_fd;
+
+ return dum;
+}
+
+struct shm_du_map * shm_du_map_open()
+{
+ struct shm_du_map * dum;
+ int shm_fd;
+ uint8_t * shm_base;
+
+ shm_fd = shm_open(SHM_DU_MAP_FILENAME, O_RDWR, 0666);
+ if (shm_fd == -1) {
+ LOG_DBGF("Failed opening shared memory.");
+ return NULL;
+ }
+
+ shm_base = mmap(NULL,
+ SHM_FILE_SIZE,
+ PROT_READ | PROT_WRITE,
+ MAP_SHARED,
+ shm_fd,
+ 0);
+ if (shm_base == MAP_FAILED) {
+ LOG_DBGF("Failed to map shared memory.");
+ if (close(shm_fd) == -1)
+ LOG_DBGF("Failed to close invalid shm.");
+
+ if (shm_unlink(SHM_DU_MAP_FILENAME) == -1)
+ LOG_DBGF("Failed to unlink invalid shm.");
+
+ return NULL;
+ }
+
+ dum = malloc(sizeof *dum);
+ if (dum == NULL) {
+ LOG_DBGF("Could not allocate struct.");
+ return NULL;
+ }
+
+ dum->shm_base = shm_base;
+ dum->ptr_head = (size_t *)
+ ((uint8_t *) dum->shm_base + SHM_BLOCKS_SIZE);
+ dum->ptr_tail = (size_t *)
+ ((uint8_t *) dum->ptr_head + sizeof(size_t));
+ dum->shm_mutex = (pthread_mutex_t *)
+ ((uint8_t *) dum->ptr_tail + sizeof(size_t));
+
+ dum->fd = shm_fd;
+
+ return dum;
+}
+
+void shm_du_map_close(struct shm_du_map * dum)
+{
+ if (dum == NULL) {
+ LOG_DBGF("Bogus input. Bugging out.");
+ return;
+ }
+
+ if (munmap(dum->shm_base, SHM_FILE_SIZE) == -1)
+ LOG_DBGF("Couldn't unmap shared memory.");
+
+ if (shm_unlink(SHM_DU_MAP_FILENAME) == -1)
+ LOG_DBGF("Failed to unlink shm.");
+
+ free(dum);
+}
+
+struct shm_du_buff * shm_create_du_buff(struct shm_du_map * dum,
+ size_t size,
+ size_t headspace,
+ uint8_t * data,
+ size_t len)
+{
+ struct shm_du_buff * sdb;
+ long blocks = 0;
+ int sz = size + sizeof *sdb;
+ int sz2 = headspace + len + sizeof *sdb;
+ uint8_t * write_pos;
+ size_t copy_len;
+
+ if (dum == NULL || data == NULL) {
+ LOG_DBGF("Bogus input, bugging out.");
+ return NULL;
+ }
+
+ if (headspace >= size) {
+ LOG_DBGF("Index out of bounds.");
+ return NULL;
+ }
+
+ if (headspace + len > size) {
+ LOG_DBGF("Buffer too small for data.");
+ return NULL;
+ }
+
+ pthread_mutex_lock(dum->shm_mutex);
+
+ while (sz > 0) {
+ sz -= SHM_DU_BUFF_BLOCK_SIZE;
+ sz2 -= SHM_DU_BUFF_BLOCK_SIZE;
+ if (sz2 < 0 && sz > 0) {
+ pthread_mutex_unlock(dum->shm_mutex);
+ LOG_DBG("Can't handle this packet now");
+ return NULL;
+ }
+ ++blocks;
+ }
+
+ if (!shm_map_free(dum, blocks)) {
+ pthread_mutex_unlock(dum->shm_mutex);
+ LOG_DBGF("Allocation failed, Out of Memory.");
+ return NULL;
+ }
+
+ sdb = get_head_ptr(dum);
+
+ sdb->size = size;
+ sdb->du_head = headspace;
+ sdb->du_tail = sdb->du_head + len;
+
+ copy_len = MIN(len, SHM_DU_BUFF_BLOCK_SIZE - headspace - sizeof *sdb);
+ write_pos = ((uint8_t *) sdb) + sizeof *sdb + headspace;
+
+ while (blocks > 0) {
+ memcpy(write_pos, data, copy_len);
+ *(dum->ptr_head) = (*dum->ptr_head + 1)
+ & (SHM_BLOCKS_IN_MAP - 1);
+ len -= copy_len;
+ copy_len = MIN(len, SHM_DU_BUFF_BLOCK_SIZE);
+ write_pos = (uint8_t *) get_head_ptr(dum);
+ --blocks;
+ }
+
+ pthread_mutex_unlock(dum->shm_mutex);
+
+ return sdb;
+}
+
+int shm_release_du_buff(struct shm_du_map * dum)
+{
+ long sz;
+ long blocks = 0;
+
+ pthread_mutex_lock(dum->shm_mutex);
+
+ if (*dum->ptr_head == *dum->ptr_tail) {
+ LOG_DBGF("Attempt to free empty ringbuffer. Nothing to do.");
+ pthread_mutex_unlock(dum->shm_mutex);
+ return -1;
+ }
+
+ sz = get_tail_ptr(dum)->size;
+
+ while (sz + (long) sizeof (struct shm_du_buff) > 0) {
+ sz -= SHM_DU_BUFF_BLOCK_SIZE;
+ ++blocks;
+ }
+
+ *(dum->ptr_tail) = (*dum->ptr_tail + blocks) & (SHM_BLOCKS_IN_MAP - 1);
+ pthread_mutex_unlock(dum->shm_mutex);
+
+ return 0;
+}
+
+uint8_t * shm_du_buff_head_alloc(struct shm_du_buff * sdb,
+ size_t size)
+{
+ if (sdb == NULL) {
+ LOG_DBGF("Bogus input, bugging out.");
+ return NULL;
+ }
+
+ if ((long) (sdb->du_head - size) < 0) {
+ LOG_DBGF("Failed to allocate PCI headspace.");
+ return NULL;
+ }
+
+ sdb->du_head -= size;
+
+ return (uint8_t *) sdb + sizeof *sdb + sdb->du_head;
+}
+
+uint8_t * shm_du_buff_tail_alloc(struct shm_du_buff * sdb,
+ size_t size)
+{
+ if (sdb == NULL) {
+ LOG_DBGF("Bogus input, bugging out.");
+ return NULL;
+ }
+
+ if (sdb->du_tail + size >= sdb->size) {
+ LOG_DBGF("Failed to allocate PCI tailspace.");
+ return NULL;
+ }
+
+ sdb->du_tail += size;
+
+ return (uint8_t *) sdb + sizeof *sdb + sdb->du_tail;
+}
+
+int shm_du_buff_head_release(struct shm_du_buff * sdb,
+ size_t size)
+{
+ if (sdb == NULL) {
+ LOG_DBGF("Bogus input, bugging out.");
+ return -EINVAL;
+ }
+
+ if (size > sdb->du_tail - sdb->du_head) {
+ LOG_DBGF("Tried to release beyond sdu boundary.");
+ return -EOVERFLOW;
+ }
+
+ sdb->du_head += size;
+
+ return sdb->du_head;
+}
+
+int shm_du_buff_tail_release(struct shm_du_buff * sdb,
+ size_t size)
+{
+ if (sdb == NULL) {
+ LOG_DBGF("Bogus input, bugging out.");
+ return -EINVAL;
+ }
+
+ if (size > sdb->du_tail - sdb->du_head) {
+ LOG_DBGF("Tried to release beyond sdu boundary.");
+ return -EOVERFLOW;
+ }
+
+ sdb->du_tail -= size;
+
+ return sdb->du_tail;
+}
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