#define MASK_LEN_TO_MOD(x) ((x) - RTE_ALIGN_FLOOR(x, MASK_ALIGN))
#define MASK_GET_IDX(idx, mod) ((idx << MASK_SHIFT) + mod)
+/*
+ * We use this to keep track of created/attached memory areas to prevent user
+ * errors in API usage.
+ */
+struct mem_area {
+ TAILQ_ENTRY(mem_area) next;
+ void *addr;
+ size_t len;
+ int fd;
+};
+TAILQ_HEAD(mem_area_head, mem_area);
+/* local per-process tailq */
+static struct mem_area_head mem_area_tailq =
+ TAILQ_HEAD_INITIALIZER(mem_area_tailq);
+static rte_spinlock_t mem_area_lock = RTE_SPINLOCK_INITIALIZER;
+
/*
* This is a mask that is always stored at the end of array, to provide fast
* way of finding free/used spots without looping through each element.
return 0;
}
+static int
+overlap(const struct mem_area *ma, const void *start, size_t len)
+{
+ const void *end = RTE_PTR_ADD(start, len);
+ const void *ma_start = ma->addr;
+ const void *ma_end = RTE_PTR_ADD(ma->addr, ma->len);
+
+ /* start overlap? */
+ if (start >= ma_start && start < ma_end)
+ return 1;
+ /* end overlap? */
+ if (end >= ma_start && end < ma_end)
+ return 1;
+ return 0;
+}
+
static int
find_next_n(const struct rte_fbarray *arr, unsigned int start, unsigned int n,
bool used)
size_t page_sz, mmap_len;
char path[PATH_MAX];
struct used_mask *msk;
+ struct mem_area *ma = NULL;
void *data = NULL;
int fd = -1;
if (fully_validate(name, elt_sz, len))
return -1;
+ /* allocate mem area before doing anything */
+ ma = malloc(sizeof(*ma));
+ if (ma == NULL) {
+ rte_errno = ENOMEM;
+ return -1;
+ }
+
page_sz = sysconf(_SC_PAGESIZE);
if (page_sz == (size_t)-1)
goto fail;
if (data == NULL)
goto fail;
+ rte_spinlock_lock(&mem_area_lock);
+
+ fd = -1;
+
if (internal_config.no_shconf) {
/* remap virtual area as writable */
void *new_data = mmap(data, mmap_len, PROT_READ | PROT_WRITE,
- MAP_FIXED | MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ MAP_FIXED | MAP_PRIVATE | MAP_ANONYMOUS, fd, 0);
if (new_data == MAP_FAILED) {
RTE_LOG(DEBUG, EAL, "%s(): couldn't remap anonymous memory: %s\n",
__func__, strerror(errno));
if (resize_and_map(fd, data, mmap_len))
goto fail;
-
- /* we've mmap'ed the file, we can now close the fd */
- close(fd);
}
+ ma->addr = data;
+ ma->len = mmap_len;
+ ma->fd = fd;
+
+ /* do not close fd - keep it until detach/destroy */
+ TAILQ_INSERT_TAIL(&mem_area_tailq, ma, next);
/* initialize the data */
memset(data, 0, mmap_len);
rte_rwlock_init(&arr->rwlock);
+ rte_spinlock_unlock(&mem_area_lock);
+
return 0;
fail:
if (data)
munmap(data, mmap_len);
if (fd >= 0)
close(fd);
+ free(ma);
+
+ rte_spinlock_unlock(&mem_area_lock);
return -1;
}
int __rte_experimental
rte_fbarray_attach(struct rte_fbarray *arr)
{
+ struct mem_area *ma = NULL, *tmp = NULL;
size_t page_sz, mmap_len;
char path[PATH_MAX];
void *data = NULL;
if (fully_validate(arr->name, arr->elt_sz, arr->len))
return -1;
+ ma = malloc(sizeof(*ma));
+ if (ma == NULL) {
+ rte_errno = ENOMEM;
+ return -1;
+ }
+
page_sz = sysconf(_SC_PAGESIZE);
if (page_sz == (size_t)-1)
goto fail;
mmap_len = calc_data_size(page_sz, arr->elt_sz, arr->len);
+ /* check the tailq - maybe user has already mapped this address space */
+ rte_spinlock_lock(&mem_area_lock);
+
+ TAILQ_FOREACH(tmp, &mem_area_tailq, next) {
+ if (overlap(tmp, arr->data, mmap_len)) {
+ rte_errno = EEXIST;
+ goto fail;
+ }
+ }
+
+ /* we know this memory area is unique, so proceed */
+
data = eal_get_virtual_area(arr->data, &mmap_len, page_sz, 0, 0);
if (data == NULL)
goto fail;
if (resize_and_map(fd, data, mmap_len))
goto fail;
- close(fd);
+ /* store our new memory area */
+ ma->addr = data;
+ ma->fd = fd; /* keep fd until detach/destroy */
+ ma->len = mmap_len;
+
+ TAILQ_INSERT_TAIL(&mem_area_tailq, ma, next);
/* we're done */
munmap(data, mmap_len);
if (fd >= 0)
close(fd);
+ free(ma);
return -1;
}
int __rte_experimental
rte_fbarray_detach(struct rte_fbarray *arr)
{
+ struct mem_area *tmp = NULL;
+ size_t mmap_len;
+ int ret = -1;
+
if (arr == NULL) {
rte_errno = EINVAL;
return -1;
if (page_sz == (size_t)-1)
return -1;
- /* this may already be unmapped (e.g. repeated call from previously
- * failed destroy(), but this is on user, we can't (easily) know if this
- * is still mapped.
- */
- munmap(arr->data, calc_data_size(page_sz, arr->elt_sz, arr->len));
+ mmap_len = calc_data_size(page_sz, arr->elt_sz, arr->len);
- return 0;
+ /* does this area exist? */
+ rte_spinlock_lock(&mem_area_lock);
+
+ TAILQ_FOREACH(tmp, &mem_area_tailq, next) {
+ if (tmp->addr == arr->data && tmp->len == mmap_len)
+ break;
+ }
+ if (tmp == NULL) {
+ rte_errno = ENOENT;
+ ret = -1;
+ goto out;
+ }
+
+ munmap(arr->data, mmap_len);
+
+ /* area is unmapped, close fd and remove the tailq entry */
+ if (tmp->fd >= 0)
+ close(tmp->fd);
+ TAILQ_REMOVE(&mem_area_tailq, tmp, next);
+ free(tmp);
+
+ ret = 0;
+out:
+ rte_spinlock_unlock(&mem_area_lock);
+ return ret;
}
int __rte_experimental
rte_fbarray_destroy(struct rte_fbarray *arr)
{
+ struct mem_area *tmp = NULL;
+ size_t mmap_len;
int fd, ret;
char path[PATH_MAX];
- ret = rte_fbarray_detach(arr);
- if (ret)
- return ret;
+ if (arr == NULL) {
+ rte_errno = EINVAL;
+ return -1;
+ }
- /* with no shconf, there were never any files to begin with */
- if (internal_config.no_shconf)
- return 0;
+ /*
+ * we don't need to synchronize detach as two values we need (element
+ * size and total capacity) are constant for the duration of life of
+ * the array, so the parts we care about will not race. if the user is
+ * detaching while doing something else in the same process, we can't
+ * really do anything about it, things will blow up either way.
+ */
- /* try deleting the file */
- eal_get_fbarray_path(path, sizeof(path), arr->name);
+ size_t page_sz = sysconf(_SC_PAGESIZE);
- fd = open(path, O_RDONLY);
- if (fd < 0) {
- RTE_LOG(ERR, EAL, "Could not open fbarray file: %s\n",
- strerror(errno));
+ if (page_sz == (size_t)-1)
return -1;
+
+ mmap_len = calc_data_size(page_sz, arr->elt_sz, arr->len);
+
+ /* does this area exist? */
+ rte_spinlock_lock(&mem_area_lock);
+
+ TAILQ_FOREACH(tmp, &mem_area_tailq, next) {
+ if (tmp->addr == arr->data && tmp->len == mmap_len)
+ break;
}
- if (flock(fd, LOCK_EX | LOCK_NB)) {
- RTE_LOG(DEBUG, EAL, "Cannot destroy fbarray - another process is using it\n");
- rte_errno = EBUSY;
+ if (tmp == NULL) {
+ rte_errno = ENOENT;
ret = -1;
- } else {
- ret = 0;
- unlink(path);
- memset(arr, 0, sizeof(*arr));
+ goto out;
}
- close(fd);
+ /* with no shconf, there were never any files to begin with */
+ if (!internal_config.no_shconf) {
+ /*
+ * attempt to get an exclusive lock on the file, to ensure it
+ * has been detached by all other processes
+ */
+ fd = tmp->fd;
+ if (flock(fd, LOCK_EX | LOCK_NB)) {
+ RTE_LOG(DEBUG, EAL, "Cannot destroy fbarray - another process is using it\n");
+ rte_errno = EBUSY;
+ ret = -1;
+ goto out;
+ }
+
+ /* we're OK to destroy the file */
+ eal_get_fbarray_path(path, sizeof(path), arr->name);
+ if (unlink(path)) {
+ RTE_LOG(DEBUG, EAL, "Cannot unlink fbarray: %s\n",
+ strerror(errno));
+ rte_errno = errno;
+ /*
+ * we're still holding an exclusive lock, so drop it to
+ * shared.
+ */
+ flock(fd, LOCK_SH | LOCK_NB);
+
+ ret = -1;
+ goto out;
+ }
+ close(fd);
+ }
+ munmap(arr->data, mmap_len);
+ /* area is unmapped, remove the tailq entry */
+ TAILQ_REMOVE(&mem_area_tailq, tmp, next);
+ free(tmp);
+ ret = 0;
+out:
+ rte_spinlock_unlock(&mem_area_lock);
return ret;
}
git.droids-corp.org / dpdk.git / commitdiff