diff options
Diffstat (limited to 'lib/librte_eal/common/eal_common_fbarray.c')
| -rw-r--r-- | lib/librte_eal/common/eal_common_fbarray.c | 1239 |
1 files changed, 1239 insertions, 0 deletions
diff --git a/lib/librte_eal/common/eal_common_fbarray.c b/lib/librte_eal/common/eal_common_fbarray.c new file mode 100644 index 00000000..43caf3ce --- /dev/null +++ b/lib/librte_eal/common/eal_common_fbarray.c @@ -0,0 +1,1239 @@ +/* SPDX-License-Identifier: BSD-3-Clause + * Copyright(c) 2017-2018 Intel Corporation + */ + +#include <inttypes.h> +#include <limits.h> +#include <sys/mman.h> +#include <stdint.h> +#include <errno.h> +#include <sys/file.h> +#include <string.h> + +#include <rte_common.h> +#include <rte_log.h> +#include <rte_errno.h> +#include <rte_spinlock.h> +#include <rte_tailq.h> + +#include "eal_filesystem.h" +#include "eal_private.h" + +#include "rte_fbarray.h" + +#define MASK_SHIFT 6ULL +#define MASK_ALIGN (1ULL << MASK_SHIFT) +#define MASK_LEN_TO_IDX(x) ((x) >> MASK_SHIFT) +#define MASK_LEN_TO_MOD(x) ((x) - RTE_ALIGN_FLOOR(x, MASK_ALIGN)) +#define MASK_GET_IDX(idx, mod) ((idx << MASK_SHIFT) + mod) + +/* + * 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. + */ + +struct used_mask { + unsigned int n_masks; + uint64_t data[]; +}; + +static size_t +calc_mask_size(unsigned int len) +{ + /* mask must be multiple of MASK_ALIGN, even though length of array + * itself may not be aligned on that boundary. + */ + len = RTE_ALIGN_CEIL(len, MASK_ALIGN); + return sizeof(struct used_mask) + + sizeof(uint64_t) * MASK_LEN_TO_IDX(len); +} + +static size_t +calc_data_size(size_t page_sz, unsigned int elt_sz, unsigned int len) +{ + size_t data_sz = elt_sz * len; + size_t msk_sz = calc_mask_size(len); + return RTE_ALIGN_CEIL(data_sz + msk_sz, page_sz); +} + +static struct used_mask * +get_used_mask(void *data, unsigned int elt_sz, unsigned int len) +{ + return (struct used_mask *) RTE_PTR_ADD(data, elt_sz * len); +} + +static int +resize_and_map(int fd, void *addr, size_t len) +{ + char path[PATH_MAX]; + void *map_addr; + + if (ftruncate(fd, len)) { + RTE_LOG(ERR, EAL, "Cannot truncate %s\n", path); + /* pass errno up the chain */ + rte_errno = errno; + return -1; + } + + map_addr = mmap(addr, len, PROT_READ | PROT_WRITE, + MAP_SHARED | MAP_FIXED, fd, 0); + if (map_addr != addr) { + RTE_LOG(ERR, EAL, "mmap() failed: %s\n", strerror(errno)); + /* pass errno up the chain */ + rte_errno = errno; + return -1; + } + return 0; +} + +static int +find_next_n(const struct rte_fbarray *arr, unsigned int start, unsigned int n, + bool used) +{ + const struct used_mask *msk = get_used_mask(arr->data, arr->elt_sz, + arr->len); + unsigned int msk_idx, lookahead_idx, first, first_mod; + unsigned int last, last_mod; + uint64_t last_msk, ignore_msk; + + /* + * mask only has granularity of MASK_ALIGN, but start may not be aligned + * on that boundary, so construct a special mask to exclude anything we + * don't want to see to avoid confusing ctz. + */ + first = MASK_LEN_TO_IDX(start); + first_mod = MASK_LEN_TO_MOD(start); + ignore_msk = ~((1ULL << first_mod) - 1); + + /* array length may not be aligned, so calculate ignore mask for last + * mask index. + */ + last = MASK_LEN_TO_IDX(arr->len); + last_mod = MASK_LEN_TO_MOD(arr->len); + last_msk = ~(-1ULL << last_mod); + + for (msk_idx = first; msk_idx < msk->n_masks; msk_idx++) { + uint64_t cur_msk, lookahead_msk; + unsigned int run_start, clz, left; + bool found = false; + /* + * The process of getting n consecutive bits for arbitrary n is + * a bit involved, but here it is in a nutshell: + * + * 1. let n be the number of consecutive bits we're looking for + * 2. check if n can fit in one mask, and if so, do n-1 + * rshift-ands to see if there is an appropriate run inside + * our current mask + * 2a. if we found a run, bail out early + * 2b. if we didn't find a run, proceed + * 3. invert the mask and count leading zeroes (that is, count + * how many consecutive set bits we had starting from the + * end of current mask) as k + * 3a. if k is 0, continue to next mask + * 3b. if k is not 0, we have a potential run + * 4. to satisfy our requirements, next mask must have n-k + * consecutive set bits right at the start, so we will do + * (n-k-1) rshift-ands and check if first bit is set. + * + * Step 4 will need to be repeated if (n-k) > MASK_ALIGN until + * we either run out of masks, lose the run, or find what we + * were looking for. + */ + cur_msk = msk->data[msk_idx]; + left = n; + + /* if we're looking for free spaces, invert the mask */ + if (!used) + cur_msk = ~cur_msk; + + /* combine current ignore mask with last index ignore mask */ + if (msk_idx == last) + ignore_msk |= last_msk; + + /* if we have an ignore mask, ignore once */ + if (ignore_msk) { + cur_msk &= ignore_msk; + ignore_msk = 0; + } + + /* if n can fit in within a single mask, do a search */ + if (n <= MASK_ALIGN) { + uint64_t tmp_msk = cur_msk; + unsigned int s_idx; + for (s_idx = 0; s_idx < n - 1; s_idx++) + tmp_msk &= tmp_msk >> 1ULL; + /* we found what we were looking for */ + if (tmp_msk != 0) { + run_start = __builtin_ctzll(tmp_msk); + return MASK_GET_IDX(msk_idx, run_start); + } + } + + /* + * we didn't find our run within the mask, or n > MASK_ALIGN, + * so we're going for plan B. + */ + + /* count leading zeroes on inverted mask */ + if (~cur_msk == 0) + clz = sizeof(cur_msk) * 8; + else + clz = __builtin_clzll(~cur_msk); + + /* if there aren't any runs at the end either, just continue */ + if (clz == 0) + continue; + + /* we have a partial run at the end, so try looking ahead */ + run_start = MASK_ALIGN - clz; + left -= clz; + + for (lookahead_idx = msk_idx + 1; lookahead_idx < msk->n_masks; + lookahead_idx++) { + unsigned int s_idx, need; + lookahead_msk = msk->data[lookahead_idx]; + + /* if we're looking for free space, invert the mask */ + if (!used) + lookahead_msk = ~lookahead_msk; + + /* figure out how many consecutive bits we need here */ + need = RTE_MIN(left, MASK_ALIGN); + + for (s_idx = 0; s_idx < need - 1; s_idx++) + lookahead_msk &= lookahead_msk >> 1ULL; + + /* if first bit is not set, we've lost the run */ + if ((lookahead_msk & 1) == 0) { + /* + * we've scanned this far, so we know there are + * no runs in the space we've lookahead-scanned + * as well, so skip that on next iteration. + */ + ignore_msk = ~((1ULL << need) - 1); + msk_idx = lookahead_idx; + break; + } + + left -= need; + + /* check if we've found what we were looking for */ + if (left == 0) { + found = true; + break; + } + } + + /* we didn't find anything, so continue */ + if (!found) + continue; + + return MASK_GET_IDX(msk_idx, run_start); + } + /* we didn't find anything */ + rte_errno = used ? ENOENT : ENOSPC; + return -1; +} + +static int +find_next(const struct rte_fbarray *arr, unsigned int start, bool used) +{ + const struct used_mask *msk = get_used_mask(arr->data, arr->elt_sz, + arr->len); + unsigned int idx, first, first_mod; + unsigned int last, last_mod; + uint64_t last_msk, ignore_msk; + + /* + * mask only has granularity of MASK_ALIGN, but start may not be aligned + * on that boundary, so construct a special mask to exclude anything we + * don't want to see to avoid confusing ctz. + */ + first = MASK_LEN_TO_IDX(start); + first_mod = MASK_LEN_TO_MOD(start); + ignore_msk = ~((1ULL << first_mod) - 1ULL); + + /* array length may not be aligned, so calculate ignore mask for last + * mask index. + */ + last = MASK_LEN_TO_IDX(arr->len); + last_mod = MASK_LEN_TO_MOD(arr->len); + last_msk = ~(-(1ULL) << last_mod); + + for (idx = first; idx < msk->n_masks; idx++) { + uint64_t cur = msk->data[idx]; + int found; + + /* if we're looking for free entries, invert mask */ + if (!used) + cur = ~cur; + + if (idx == last) + cur &= last_msk; + + /* ignore everything before start on first iteration */ + if (idx == first) + cur &= ignore_msk; + + /* check if we have any entries */ + if (cur == 0) + continue; + + /* + * find first set bit - that will correspond to whatever it is + * that we're looking for. + */ + found = __builtin_ctzll(cur); + return MASK_GET_IDX(idx, found); + } + /* we didn't find anything */ + rte_errno = used ? ENOENT : ENOSPC; + return -1; +} + +static int +find_contig(const struct rte_fbarray *arr, unsigned int start, bool used) +{ + const struct used_mask *msk = get_used_mask(arr->data, arr->elt_sz, + arr->len); + unsigned int idx, first, first_mod; + unsigned int last, last_mod; + uint64_t last_msk; + unsigned int need_len, result = 0; + + /* array length may not be aligned, so calculate ignore mask for last + * mask index. + */ + last = MASK_LEN_TO_IDX(arr->len); + last_mod = MASK_LEN_TO_MOD(arr->len); + last_msk = ~(-(1ULL) << last_mod); + + first = MASK_LEN_TO_IDX(start); + first_mod = MASK_LEN_TO_MOD(start); + for (idx = first; idx < msk->n_masks; idx++, result += need_len) { + uint64_t cur = msk->data[idx]; + unsigned int run_len; + + need_len = MASK_ALIGN; + + /* if we're looking for free entries, invert mask */ + if (!used) + cur = ~cur; + + /* if this is last mask, ignore everything after last bit */ + if (idx == last) + cur &= last_msk; + + /* ignore everything before start on first iteration */ + if (idx == first) { + cur >>= first_mod; + /* at the start, we don't need the full mask len */ + need_len -= first_mod; + } + + /* we will be looking for zeroes, so invert the mask */ + cur = ~cur; + + /* if mask is zero, we have a complete run */ + if (cur == 0) + continue; + + /* + * see if current run ends before mask end. + */ + run_len = __builtin_ctzll(cur); + + /* add however many zeroes we've had in the last run and quit */ + if (run_len < need_len) { + result += run_len; + break; + } + } + return result; +} + +static int +find_prev_n(const struct rte_fbarray *arr, unsigned int start, unsigned int n, + bool used) +{ + const struct used_mask *msk = get_used_mask(arr->data, arr->elt_sz, + arr->len); + unsigned int msk_idx, lookbehind_idx, first, first_mod; + uint64_t ignore_msk; + + /* + * mask only has granularity of MASK_ALIGN, but start may not be aligned + * on that boundary, so construct a special mask to exclude anything we + * don't want to see to avoid confusing ctz. + */ + first = MASK_LEN_TO_IDX(start); + first_mod = MASK_LEN_TO_MOD(start); + /* we're going backwards, so mask must start from the top */ + ignore_msk = first_mod == MASK_ALIGN - 1 ? + -1ULL : /* prevent overflow */ + ~(-1ULL << (first_mod + 1)); + + /* go backwards, include zero */ + msk_idx = first; + do { + uint64_t cur_msk, lookbehind_msk; + unsigned int run_start, run_end, ctz, left; + bool found = false; + /* + * The process of getting n consecutive bits from the top for + * arbitrary n is a bit involved, but here it is in a nutshell: + * + * 1. let n be the number of consecutive bits we're looking for + * 2. check if n can fit in one mask, and if so, do n-1 + * lshift-ands to see if there is an appropriate run inside + * our current mask + * 2a. if we found a run, bail out early + * 2b. if we didn't find a run, proceed + * 3. invert the mask and count trailing zeroes (that is, count + * how many consecutive set bits we had starting from the + * start of current mask) as k + * 3a. if k is 0, continue to next mask + * 3b. if k is not 0, we have a potential run + * 4. to satisfy our requirements, next mask must have n-k + * consecutive set bits at the end, so we will do (n-k-1) + * lshift-ands and check if last bit is set. + * + * Step 4 will need to be repeated if (n-k) > MASK_ALIGN until + * we either run out of masks, lose the run, or find what we + * were looking for. + */ + cur_msk = msk->data[msk_idx]; + left = n; + + /* if we're looking for free spaces, invert the mask */ + if (!used) + cur_msk = ~cur_msk; + + /* if we have an ignore mask, ignore once */ + if (ignore_msk) { + cur_msk &= ignore_msk; + ignore_msk = 0; + } + + /* if n can fit in within a single mask, do a search */ + if (n <= MASK_ALIGN) { + uint64_t tmp_msk = cur_msk; + unsigned int s_idx; + for (s_idx = 0; s_idx < n - 1; s_idx++) + tmp_msk &= tmp_msk << 1ULL; + /* we found what we were looking for */ + if (tmp_msk != 0) { + /* clz will give us offset from end of mask, and + * we only get the end of our run, not start, + * so adjust result to point to where start + * would have been. + */ + run_start = MASK_ALIGN - + __builtin_clzll(tmp_msk) - n; + return MASK_GET_IDX(msk_idx, run_start); + } + } + + /* + * we didn't find our run within the mask, or n > MASK_ALIGN, + * so we're going for plan B. + */ + + /* count trailing zeroes on inverted mask */ + if (~cur_msk == 0) + ctz = sizeof(cur_msk) * 8; + else + ctz = __builtin_ctzll(~cur_msk); + + /* if there aren't any runs at the start either, just + * continue + */ + if (ctz == 0) + continue; + + /* we have a partial run at the start, so try looking behind */ + run_end = MASK_GET_IDX(msk_idx, ctz); + left -= ctz; + + /* go backwards, include zero */ + lookbehind_idx = msk_idx - 1; + + /* we can't lookbehind as we've run out of masks, so stop */ + if (msk_idx == 0) + break; + + do { + const uint64_t last_bit = 1ULL << (MASK_ALIGN - 1); + unsigned int s_idx, need; + + lookbehind_msk = msk->data[lookbehind_idx]; + + /* if we're looking for free space, invert the mask */ + if (!used) + lookbehind_msk = ~lookbehind_msk; + + /* figure out how many consecutive bits we need here */ + need = RTE_MIN(left, MASK_ALIGN); + + for (s_idx = 0; s_idx < need - 1; s_idx++) + lookbehind_msk &= lookbehind_msk << 1ULL; + + /* if last bit is not set, we've lost the run */ + if ((lookbehind_msk & last_bit) == 0) { + /* + * we've scanned this far, so we know there are + * no runs in the space we've lookbehind-scanned + * as well, so skip that on next iteration. + */ + ignore_msk = -1ULL << need; + msk_idx = lookbehind_idx; + break; + } + + left -= need; + + /* check if we've found what we were looking for */ + if (left == 0) { + found = true; + break; + } + } while ((lookbehind_idx--) != 0); /* decrement after check to + * include zero + */ + + /* we didn't find anything, so continue */ + if (!found) + continue; + + /* we've found what we were looking for, but we only know where + * the run ended, so calculate start position. + */ + return run_end - n; + } while (msk_idx-- != 0); /* decrement after check to include zero */ + /* we didn't find anything */ + rte_errno = used ? ENOENT : ENOSPC; + return -1; +} + +static int +find_prev(const struct rte_fbarray *arr, unsigned int start, bool used) +{ + const struct used_mask *msk = get_used_mask(arr->data, arr->elt_sz, + arr->len); + unsigned int idx, first, first_mod; + uint64_t ignore_msk; + + /* + * mask only has granularity of MASK_ALIGN, but start may not be aligned + * on that boundary, so construct a special mask to exclude anything we + * don't want to see to avoid confusing clz. + */ + first = MASK_LEN_TO_IDX(start); + first_mod = MASK_LEN_TO_MOD(start); + /* we're going backwards, so mask must start from the top */ + ignore_msk = first_mod == MASK_ALIGN - 1 ? + -1ULL : /* prevent overflow */ + ~(-1ULL << (first_mod + 1)); + + /* go backwards, include zero */ + idx = first; + do { + uint64_t cur = msk->data[idx]; + int found; + + /* if we're looking for free entries, invert mask */ + if (!used) + cur = ~cur; + + /* ignore everything before start on first iteration */ + if (idx == first) + cur &= ignore_msk; + + /* check if we have any entries */ + if (cur == 0) + continue; + + /* + * find last set bit - that will correspond to whatever it is + * that we're looking for. we're counting trailing zeroes, thus + * the value we get is counted from end of mask, so calculate + * position from start of mask. + */ + found = MASK_ALIGN - __builtin_clzll(cur) - 1; + + return MASK_GET_IDX(idx, found); + } while (idx-- != 0); /* decrement after check to include zero*/ + + /* we didn't find anything */ + rte_errno = used ? ENOENT : ENOSPC; + return -1; +} + +static int +find_rev_contig(const struct rte_fbarray *arr, unsigned int start, bool used) +{ + const struct used_mask *msk = get_used_mask(arr->data, arr->elt_sz, + arr->len); + unsigned int idx, first, first_mod; + unsigned int need_len, result = 0; + + first = MASK_LEN_TO_IDX(start); + first_mod = MASK_LEN_TO_MOD(start); + + /* go backwards, include zero */ + idx = first; + do { + uint64_t cur = msk->data[idx]; + unsigned int run_len; + + need_len = MASK_ALIGN; + + /* if we're looking for free entries, invert mask */ + if (!used) + cur = ~cur; + + /* ignore everything after start on first iteration */ + if (idx == first) { + unsigned int end_len = MASK_ALIGN - first_mod - 1; + cur <<= end_len; + /* at the start, we don't need the full mask len */ + need_len -= end_len; + } + + /* we will be looking for zeroes, so invert the mask */ + cur = ~cur; + + /* if mask is zero, we have a complete run */ + if (cur == 0) + goto endloop; + + /* + * see where run ends, starting from the end. + */ + run_len = __builtin_clzll(cur); + + /* add however many zeroes we've had in the last run and quit */ + if (run_len < need_len) { + result += run_len; + break; + } +endloop: + result += need_len; + } while (idx-- != 0); /* decrement after check to include zero */ + return result; +} + +static int +set_used(struct rte_fbarray *arr, unsigned int idx, bool used) +{ + struct used_mask *msk; + uint64_t msk_bit = 1ULL << MASK_LEN_TO_MOD(idx); + unsigned int msk_idx = MASK_LEN_TO_IDX(idx); + bool already_used; + int ret = -1; + + if (arr == NULL || idx >= arr->len) { + rte_errno = EINVAL; + return -1; + } + msk = get_used_mask(arr->data, arr->elt_sz, arr->len); + ret = 0; + + /* prevent array from changing under us */ + rte_rwlock_write_lock(&arr->rwlock); + + already_used = (msk->data[msk_idx] & msk_bit) != 0; + + /* nothing to be done */ + if (used == already_used) + goto out; + + if (used) { + msk->data[msk_idx] |= msk_bit; + arr->count++; + } else { + msk->data[msk_idx] &= ~msk_bit; + arr->count--; + } +out: + rte_rwlock_write_unlock(&arr->rwlock); + + return ret; +} + +static int +fully_validate(const char *name, unsigned int elt_sz, unsigned int len) +{ + if (name == NULL || elt_sz == 0 || len == 0 || len > INT_MAX) { + rte_errno = EINVAL; + return -1; + } + + if (strnlen(name, RTE_FBARRAY_NAME_LEN) == RTE_FBARRAY_NAME_LEN) { + rte_errno = ENAMETOOLONG; + return -1; + } + return 0; +} + +int __rte_experimental +rte_fbarray_init(struct rte_fbarray *arr, const char *name, unsigned int len, + unsigned int elt_sz) +{ + size_t page_sz, mmap_len; + char path[PATH_MAX]; + struct used_mask *msk; + void *data = NULL; + int fd = -1; + + if (arr == NULL) { + rte_errno = EINVAL; + return -1; + } + + if (fully_validate(name, elt_sz, len)) + return -1; + + page_sz = sysconf(_SC_PAGESIZE); + if (page_sz == (size_t)-1) + goto fail; + + /* calculate our memory limits */ + mmap_len = calc_data_size(page_sz, elt_sz, len); + + data = eal_get_virtual_area(NULL, &mmap_len, page_sz, 0, 0); + if (data == NULL) + goto fail; + + 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); + if (new_data == MAP_FAILED) { + RTE_LOG(DEBUG, EAL, "%s(): couldn't remap anonymous memory: %s\n", + __func__, strerror(errno)); + goto fail; + } + } else { + eal_get_fbarray_path(path, sizeof(path), name); + + /* + * Each fbarray is unique to process namespace, i.e. the + * filename depends on process prefix. Try to take out a lock + * and see if we succeed. If we don't, someone else is using it + * already. + */ + fd = open(path, O_CREAT | O_RDWR, 0600); + if (fd < 0) { + RTE_LOG(DEBUG, EAL, "%s(): couldn't open %s: %s\n", + __func__, path, strerror(errno)); + rte_errno = errno; + goto fail; + } else if (flock(fd, LOCK_EX | LOCK_NB)) { + RTE_LOG(DEBUG, EAL, "%s(): couldn't lock %s: %s\n", + __func__, path, strerror(errno)); + rte_errno = EBUSY; + goto fail; + } + + /* take out a non-exclusive lock, so that other processes could + * still attach to it, but no other process could reinitialize + * it. + */ + if (flock(fd, LOCK_SH | LOCK_NB)) { + rte_errno = errno; + goto fail; + } + + if (resize_and_map(fd, data, mmap_len)) + goto fail; + + /* we've mmap'ed the file, we can now close the fd */ + close(fd); + } + + /* initialize the data */ + memset(data, 0, mmap_len); + + /* populate data structure */ + strlcpy(arr->name, name, sizeof(arr->name)); + arr->data = data; + arr->len = len; + arr->elt_sz = elt_sz; + arr->count = 0; + + msk = get_used_mask(data, elt_sz, len); + msk->n_masks = MASK_LEN_TO_IDX(RTE_ALIGN_CEIL(len, MASK_ALIGN)); + + rte_rwlock_init(&arr->rwlock); + + return 0; +fail: + if (data) + munmap(data, mmap_len); + if (fd >= 0) + close(fd); + return -1; +} + +int __rte_experimental +rte_fbarray_attach(struct rte_fbarray *arr) +{ + size_t page_sz, mmap_len; + char path[PATH_MAX]; + void *data = NULL; + int fd = -1; + + if (arr == NULL) { + rte_errno = EINVAL; + return -1; + } + + /* + * we don't need to synchronize attach as two values we need (element + * size and array length) are constant for the duration of life of + * the array, so the parts we care about will not race. + */ + + if (fully_validate(arr->name, arr->elt_sz, arr->len)) + 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); + + data = eal_get_virtual_area(arr->data, &mmap_len, page_sz, 0, 0); + if (data == NULL) + goto fail; + + eal_get_fbarray_path(path, sizeof(path), arr->name); + + fd = open(path, O_RDWR); + if (fd < 0) { + rte_errno = errno; + goto fail; + } + + /* lock the file, to let others know we're using it */ + if (flock(fd, LOCK_SH | LOCK_NB)) { + rte_errno = errno; + goto fail; + } + + if (resize_and_map(fd, data, mmap_len)) + goto fail; + + close(fd); + + /* we're done */ + + return 0; +fail: + if (data) + munmap(data, mmap_len); + if (fd >= 0) + close(fd); + return -1; +} + +int __rte_experimental +rte_fbarray_detach(struct rte_fbarray *arr) +{ + if (arr == NULL) { + rte_errno = EINVAL; + return -1; + } + + /* + * 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. + */ + + size_t page_sz = sysconf(_SC_PAGESIZE); + + 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)); + + return 0; +} + +int __rte_experimental +rte_fbarray_destroy(struct rte_fbarray *arr) +{ + int fd, ret; + char path[PATH_MAX]; + + ret = rte_fbarray_detach(arr); + if (ret) + return ret; + + /* try deleting the file */ + eal_get_fbarray_path(path, sizeof(path), arr->name); + + fd = open(path, O_RDONLY); + if (fd < 0) { + RTE_LOG(ERR, EAL, "Could not open fbarray file: %s\n", + strerror(errno)); + return -1; + } + 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; + } else { + ret = 0; + unlink(path); + memset(arr, 0, sizeof(*arr)); + } + close(fd); + + return ret; +} + +void * __rte_experimental +rte_fbarray_get(const struct rte_fbarray *arr, unsigned int idx) +{ + void *ret = NULL; + if (arr == NULL) { + rte_errno = EINVAL; + return NULL; + } + + if (idx >= arr->len) { + rte_errno = EINVAL; + return NULL; + } + + ret = RTE_PTR_ADD(arr->data, idx * arr->elt_sz); + + return ret; +} + +int __rte_experimental +rte_fbarray_set_used(struct rte_fbarray *arr, unsigned int idx) +{ + return set_used(arr, idx, true); +} + +int __rte_experimental +rte_fbarray_set_free(struct rte_fbarray *arr, unsigned int idx) +{ + return set_used(arr, idx, false); +} + +int __rte_experimental +rte_fbarray_is_used(struct rte_fbarray *arr, unsigned int idx) +{ + struct used_mask *msk; + int msk_idx; + uint64_t msk_bit; + int ret = -1; + + if (arr == NULL || idx >= arr->len) { + rte_errno = EINVAL; + return -1; + } + + /* prevent array from changing under us */ + rte_rwlock_read_lock(&arr->rwlock); + + msk = get_used_mask(arr->data, arr->elt_sz, arr->len); + msk_idx = MASK_LEN_TO_IDX(idx); + msk_bit = 1ULL << MASK_LEN_TO_MOD(idx); + + ret = (msk->data[msk_idx] & msk_bit) != 0; + + rte_rwlock_read_unlock(&arr->rwlock); + + return ret; +} + +static int +fbarray_find(struct rte_fbarray *arr, unsigned int start, bool next, bool used) +{ + int ret = -1; + + if (arr == NULL || start >= arr->len) { + rte_errno = EINVAL; + return -1; + } + + /* prevent array from changing under us */ + rte_rwlock_read_lock(&arr->rwlock); + + /* cheap checks to prevent doing useless work */ + if (!used) { + if (arr->len == arr->count) { + rte_errno = ENOSPC; + goto out; + } + if (arr->count == 0) { + ret = start; + goto out; + } + } else { + if (arr->count == 0) { + rte_errno = ENOENT; + goto out; + } + if (arr->len == arr->count) { + ret = start; + goto out; + } + } + if (next) + ret = find_next(arr, start, used); + else + ret = find_prev(arr, start, used); +out: + rte_rwlock_read_unlock(&arr->rwlock); + return ret; +} + +int __rte_experimental +rte_fbarray_find_next_free(struct rte_fbarray *arr, unsigned int start) +{ + return fbarray_find(arr, start, true, false); +} + +int __rte_experimental +rte_fbarray_find_next_used(struct rte_fbarray *arr, unsigned int start) +{ + return fbarray_find(arr, start, true, true); +} + +int __rte_experimental +rte_fbarray_find_prev_free(struct rte_fbarray *arr, unsigned int start) +{ + return fbarray_find(arr, start, false, false); +} + +int __rte_experimental +rte_fbarray_find_prev_used(struct rte_fbarray *arr, unsigned int start) +{ + return fbarray_find(arr, start, false, true); +} + +static int +fbarray_find_n(struct rte_fbarray *arr, unsigned int start, unsigned int n, + bool next, bool used) +{ + int ret = -1; + + if (arr == NULL || start >= arr->len || n > arr->len || n == 0) { + rte_errno = EINVAL; + return -1; + } + if (next && (arr->len - start) < n) { + rte_errno = used ? ENOENT : ENOSPC; + return -1; + } + if (!next && start < (n - 1)) { + rte_errno = used ? ENOENT : ENOSPC; + return -1; + } + + /* prevent array from changing under us */ + rte_rwlock_read_lock(&arr->rwlock); + + /* cheap checks to prevent doing useless work */ + if (!used) { + if (arr->len == arr->count || arr->len - arr->count < n) { + rte_errno = ENOSPC; + goto out; + } + if (arr->count == 0) { + ret = next ? start : start - n + 1; + goto out; + } + } else { + if (arr->count < n) { + rte_errno = ENOENT; + goto out; + } + if (arr->count == arr->len) { + ret = next ? start : start - n + 1; + goto out; + } + } + + if (next) + ret = find_next_n(arr, start, n, used); + else + ret = find_prev_n(arr, start, n, used); +out: + rte_rwlock_read_unlock(&arr->rwlock); + return ret; +} + +int __rte_experimental +rte_fbarray_find_next_n_free(struct rte_fbarray *arr, unsigned int start, + unsigned int n) +{ + return fbarray_find_n(arr, start, n, true, false); +} + +int __rte_experimental +rte_fbarray_find_next_n_used(struct rte_fbarray *arr, unsigned int start, + unsigned int n) +{ + return fbarray_find_n(arr, start, n, true, true); +} + +int __rte_experimental +rte_fbarray_find_prev_n_free(struct rte_fbarray *arr, unsigned int start, + unsigned int n) +{ + return fbarray_find_n(arr, start, n, false, false); +} + +int __rte_experimental +rte_fbarray_find_prev_n_used(struct rte_fbarray *arr, unsigned int start, + unsigned int n) +{ + return fbarray_find_n(arr, start, n, false, true); +} + +static int +fbarray_find_contig(struct rte_fbarray *arr, unsigned int start, bool next, + bool used) +{ + int ret = -1; + + if (arr == NULL || start >= arr->len) { + rte_errno = EINVAL; + return -1; + } + + /* prevent array from changing under us */ + rte_rwlock_read_lock(&arr->rwlock); + + /* cheap checks to prevent doing useless work */ + if (used) { + if (arr->count == 0) { + ret = 0; + goto out; + } + if (next && arr->count == arr->len) { + ret = arr->len - start; + goto out; + } + if (!next && arr->count == arr->len) { + ret = start + 1; + goto out; + } + } else { + if (arr->len == arr->count) { + ret = 0; + goto out; + } + if (next && arr->count == 0) { + ret = arr->len - start; + goto out; + } + if (!next && arr->count == 0) { + ret = start + 1; + goto out; + } + } + + if (next) + ret = find_contig(arr, start, used); + else + ret = find_rev_contig(arr, start, used); +out: + rte_rwlock_read_unlock(&arr->rwlock); + return ret; +} + +int __rte_experimental +rte_fbarray_find_contig_free(struct rte_fbarray *arr, unsigned int start) +{ + return fbarray_find_contig(arr, start, true, false); +} + +int __rte_experimental +rte_fbarray_find_contig_used(struct rte_fbarray *arr, unsigned int start) +{ + return fbarray_find_contig(arr, start, true, true); +} + +int __rte_experimental +rte_fbarray_find_rev_contig_free(struct rte_fbarray *arr, unsigned int start) +{ + return fbarray_find_contig(arr, start, false, false); +} + +int __rte_experimental +rte_fbarray_find_rev_contig_used(struct rte_fbarray *arr, unsigned int start) +{ + return fbarray_find_contig(arr, start, false, true); +} + +int __rte_experimental +rte_fbarray_find_idx(const struct rte_fbarray *arr, const void *elt) +{ + void *end; + int ret = -1; + + /* + * no need to synchronize as it doesn't matter if underlying data + * changes - we're doing pointer arithmetic here. + */ + + if (arr == NULL || elt == NULL) { + rte_errno = EINVAL; + return -1; + } + end = RTE_PTR_ADD(arr->data, arr->elt_sz * arr->len); + if (elt < arr->data || elt >= end) { + rte_errno = EINVAL; + return -1; + } + + ret = RTE_PTR_DIFF(elt, arr->data) / arr->elt_sz; + + return ret; +} + +void __rte_experimental +rte_fbarray_dump_metadata(struct rte_fbarray *arr, FILE *f) +{ + struct used_mask *msk; + unsigned int i; + + if (arr == NULL || f == NULL) { + rte_errno = EINVAL; + return; + } + + if (fully_validate(arr->name, arr->elt_sz, arr->len)) { + fprintf(f, "Invalid file-backed array\n"); + goto out; + } + + /* prevent array from changing under us */ + rte_rwlock_read_lock(&arr->rwlock); + + fprintf(f, "File-backed array: %s\n", arr->name); + fprintf(f, "size: %i occupied: %i elt_sz: %i\n", + arr->len, arr->count, arr->elt_sz); + + msk = get_used_mask(arr->data, arr->elt_sz, arr->len); + + for (i = 0; i < msk->n_masks; i++) + fprintf(f, "msk idx %i: 0x%016" PRIx64 "\n", i, msk->data[i]); +out: + rte_rwlock_read_unlock(&arr->rwlock); +} |