diff options
Diffstat (limited to 'drivers/net/sfc/filter.c')
| -rw-r--r-- | drivers/net/sfc/filter.c | 454 |
1 files changed, 454 insertions, 0 deletions
diff --git a/drivers/net/sfc/filter.c b/drivers/net/sfc/filter.c new file mode 100644 index 00000000000..52cb6082b91 --- /dev/null +++ b/drivers/net/sfc/filter.c @@ -0,0 +1,454 @@ +/**************************************************************************** + * Driver for Solarflare Solarstorm network controllers and boards + * Copyright 2005-2010 Solarflare Communications Inc. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published + * by the Free Software Foundation, incorporated herein by reference. + */ + +#include "efx.h" +#include "filter.h" +#include "io.h" +#include "nic.h" +#include "regs.h" + +/* "Fudge factors" - difference between programmed value and actual depth. + * Due to pipelined implementation we need to program H/W with a value that + * is larger than the hop limit we want. + */ +#define FILTER_CTL_SRCH_FUDGE_WILD 3 +#define FILTER_CTL_SRCH_FUDGE_FULL 1 + +/* Hard maximum hop limit. Hardware will time-out beyond 200-something. + * We also need to avoid infinite loops in efx_filter_search() when the + * table is full. + */ +#define FILTER_CTL_SRCH_MAX 200 + +struct efx_filter_table { + u32 offset; /* address of table relative to BAR */ + unsigned size; /* number of entries */ + unsigned step; /* step between entries */ + unsigned used; /* number currently used */ + unsigned long *used_bitmap; + struct efx_filter_spec *spec; +}; + +struct efx_filter_state { + spinlock_t lock; + struct efx_filter_table table[EFX_FILTER_TABLE_COUNT]; + unsigned search_depth[EFX_FILTER_TYPE_COUNT]; +}; + +/* The filter hash function is LFSR polynomial x^16 + x^3 + 1 of a 32-bit + * key derived from the n-tuple. The initial LFSR state is 0xffff. */ +static u16 efx_filter_hash(u32 key) +{ + u16 tmp; + + /* First 16 rounds */ + tmp = 0x1fff ^ key >> 16; + tmp = tmp ^ tmp >> 3 ^ tmp >> 6; + tmp = tmp ^ tmp >> 9; + /* Last 16 rounds */ + tmp = tmp ^ tmp << 13 ^ key; + tmp = tmp ^ tmp >> 3 ^ tmp >> 6; + return tmp ^ tmp >> 9; +} + +/* To allow for hash collisions, filter search continues at these + * increments from the first possible entry selected by the hash. */ +static u16 efx_filter_increment(u32 key) +{ + return key * 2 - 1; +} + +static enum efx_filter_table_id +efx_filter_type_table_id(enum efx_filter_type type) +{ + BUILD_BUG_ON(EFX_FILTER_TABLE_RX_IP != (EFX_FILTER_RX_TCP_FULL >> 2)); + BUILD_BUG_ON(EFX_FILTER_TABLE_RX_IP != (EFX_FILTER_RX_TCP_WILD >> 2)); + BUILD_BUG_ON(EFX_FILTER_TABLE_RX_IP != (EFX_FILTER_RX_UDP_FULL >> 2)); + BUILD_BUG_ON(EFX_FILTER_TABLE_RX_IP != (EFX_FILTER_RX_UDP_WILD >> 2)); + BUILD_BUG_ON(EFX_FILTER_TABLE_RX_MAC != (EFX_FILTER_RX_MAC_FULL >> 2)); + BUILD_BUG_ON(EFX_FILTER_TABLE_RX_MAC != (EFX_FILTER_RX_MAC_WILD >> 2)); + return type >> 2; +} + +static void +efx_filter_table_reset_search_depth(struct efx_filter_state *state, + enum efx_filter_table_id table_id) +{ + memset(state->search_depth + (table_id << 2), 0, + sizeof(state->search_depth[0]) << 2); +} + +static void efx_filter_push_rx_limits(struct efx_nic *efx) +{ + struct efx_filter_state *state = efx->filter_state; + efx_oword_t filter_ctl; + + efx_reado(efx, &filter_ctl, FR_BZ_RX_FILTER_CTL); + + EFX_SET_OWORD_FIELD(filter_ctl, FRF_BZ_TCP_FULL_SRCH_LIMIT, + state->search_depth[EFX_FILTER_RX_TCP_FULL] + + FILTER_CTL_SRCH_FUDGE_FULL); + EFX_SET_OWORD_FIELD(filter_ctl, FRF_BZ_TCP_WILD_SRCH_LIMIT, + state->search_depth[EFX_FILTER_RX_TCP_WILD] + + FILTER_CTL_SRCH_FUDGE_WILD); + EFX_SET_OWORD_FIELD(filter_ctl, FRF_BZ_UDP_FULL_SRCH_LIMIT, + state->search_depth[EFX_FILTER_RX_UDP_FULL] + + FILTER_CTL_SRCH_FUDGE_FULL); + EFX_SET_OWORD_FIELD(filter_ctl, FRF_BZ_UDP_WILD_SRCH_LIMIT, + state->search_depth[EFX_FILTER_RX_UDP_WILD] + + FILTER_CTL_SRCH_FUDGE_WILD); + + if (state->table[EFX_FILTER_TABLE_RX_MAC].size) { + EFX_SET_OWORD_FIELD( + filter_ctl, FRF_CZ_ETHERNET_FULL_SEARCH_LIMIT, + state->search_depth[EFX_FILTER_RX_MAC_FULL] + + FILTER_CTL_SRCH_FUDGE_FULL); + EFX_SET_OWORD_FIELD( + filter_ctl, FRF_CZ_ETHERNET_WILDCARD_SEARCH_LIMIT, + state->search_depth[EFX_FILTER_RX_MAC_WILD] + + FILTER_CTL_SRCH_FUDGE_WILD); + } + + efx_writeo(efx, &filter_ctl, FR_BZ_RX_FILTER_CTL); +} + +/* Build a filter entry and return its n-tuple key. */ +static u32 efx_filter_build(efx_oword_t *filter, struct efx_filter_spec *spec) +{ + u32 data3; + + switch (efx_filter_type_table_id(spec->type)) { + case EFX_FILTER_TABLE_RX_IP: { + bool is_udp = (spec->type == EFX_FILTER_RX_UDP_FULL || + spec->type == EFX_FILTER_RX_UDP_WILD); + EFX_POPULATE_OWORD_7( + *filter, + FRF_BZ_RSS_EN, + !!(spec->flags & EFX_FILTER_FLAG_RX_RSS), + FRF_BZ_SCATTER_EN, + !!(spec->flags & EFX_FILTER_FLAG_RX_SCATTER), + FRF_BZ_TCP_UDP, is_udp, + FRF_BZ_RXQ_ID, spec->dmaq_id, + EFX_DWORD_2, spec->data[2], + EFX_DWORD_1, spec->data[1], + EFX_DWORD_0, spec->data[0]); + data3 = is_udp; + break; + } + + case EFX_FILTER_TABLE_RX_MAC: { + bool is_wild = spec->type == EFX_FILTER_RX_MAC_WILD; + EFX_POPULATE_OWORD_8( + *filter, + FRF_CZ_RMFT_RSS_EN, + !!(spec->flags & EFX_FILTER_FLAG_RX_RSS), + FRF_CZ_RMFT_SCATTER_EN, + !!(spec->flags & EFX_FILTER_FLAG_RX_SCATTER), + FRF_CZ_RMFT_IP_OVERRIDE, + !!(spec->flags & EFX_FILTER_FLAG_RX_OVERRIDE_IP), + FRF_CZ_RMFT_RXQ_ID, spec->dmaq_id, + FRF_CZ_RMFT_WILDCARD_MATCH, is_wild, + FRF_CZ_RMFT_DEST_MAC_HI, spec->data[2], + FRF_CZ_RMFT_DEST_MAC_LO, spec->data[1], + FRF_CZ_RMFT_VLAN_ID, spec->data[0]); + data3 = is_wild; + break; + } + + default: + BUG(); + } + + return spec->data[0] ^ spec->data[1] ^ spec->data[2] ^ data3; +} + +static bool efx_filter_equal(const struct efx_filter_spec *left, + const struct efx_filter_spec *right) +{ + if (left->type != right->type || + memcmp(left->data, right->data, sizeof(left->data))) + return false; + + return true; +} + +static int efx_filter_search(struct efx_filter_table *table, + struct efx_filter_spec *spec, u32 key, + bool for_insert, int *depth_required) +{ + unsigned hash, incr, filter_idx, depth; + struct efx_filter_spec *cmp; + + hash = efx_filter_hash(key); + incr = efx_filter_increment(key); + + for (depth = 1, filter_idx = hash & (table->size - 1); + depth <= FILTER_CTL_SRCH_MAX && + test_bit(filter_idx, table->used_bitmap); + ++depth) { + cmp = &table->spec[filter_idx]; + if (efx_filter_equal(spec, cmp)) + goto found; + filter_idx = (filter_idx + incr) & (table->size - 1); + } + if (!for_insert) + return -ENOENT; + if (depth > FILTER_CTL_SRCH_MAX) + return -EBUSY; +found: + *depth_required = depth; + return filter_idx; +} + +/** + * efx_filter_insert_filter - add or replace a filter + * @efx: NIC in which to insert the filter + * @spec: Specification for the filter + * @replace: Flag for whether the specified filter may replace a filter + * with an identical match expression and equal or lower priority + * + * On success, return the filter index within its table. + * On failure, return a negative error code. + */ +int efx_filter_insert_filter(struct efx_nic *efx, struct efx_filter_spec *spec, + bool replace) +{ + struct efx_filter_state *state = efx->filter_state; + enum efx_filter_table_id table_id = + efx_filter_type_table_id(spec->type); + struct efx_filter_table *table = &state->table[table_id]; + struct efx_filter_spec *saved_spec; + efx_oword_t filter; + int filter_idx, depth; + u32 key; + int rc; + + if (table->size == 0) + return -EINVAL; + + key = efx_filter_build(&filter, spec); + + netif_vdbg(efx, hw, efx->net_dev, + "%s: type %d search_depth=%d", __func__, spec->type, + state->search_depth[spec->type]); + + spin_lock_bh(&state->lock); + + rc = efx_filter_search(table, spec, key, true, &depth); + if (rc < 0) + goto out; + filter_idx = rc; + BUG_ON(filter_idx >= table->size); + saved_spec = &table->spec[filter_idx]; + + if (test_bit(filter_idx, table->used_bitmap)) { + /* Should we replace the existing filter? */ + if (!replace) { + rc = -EEXIST; + goto out; + } + if (spec->priority < saved_spec->priority) { + rc = -EPERM; + goto out; + } + } else { + __set_bit(filter_idx, table->used_bitmap); + ++table->used; + } + *saved_spec = *spec; + + if (state->search_depth[spec->type] < depth) { + state->search_depth[spec->type] = depth; + efx_filter_push_rx_limits(efx); + } + + efx_writeo(efx, &filter, table->offset + table->step * filter_idx); + + netif_vdbg(efx, hw, efx->net_dev, + "%s: filter type %d index %d rxq %u set", + __func__, spec->type, filter_idx, spec->dmaq_id); + +out: + spin_unlock_bh(&state->lock); + return rc; +} + +static void efx_filter_table_clear_entry(struct efx_nic *efx, + struct efx_filter_table *table, + int filter_idx) +{ + static efx_oword_t filter; + + if (test_bit(filter_idx, table->used_bitmap)) { + __clear_bit(filter_idx, table->used_bitmap); + --table->used; + memset(&table->spec[filter_idx], 0, sizeof(table->spec[0])); + + efx_writeo(efx, &filter, + table->offset + table->step * filter_idx); + } +} + +/** + * efx_filter_remove_filter - remove a filter by specification + * @efx: NIC from which to remove the filter + * @spec: Specification for the filter + * + * On success, return zero. + * On failure, return a negative error code. + */ +int efx_filter_remove_filter(struct efx_nic *efx, struct efx_filter_spec *spec) +{ + struct efx_filter_state *state = efx->filter_state; + enum efx_filter_table_id table_id = + efx_filter_type_table_id(spec->type); + struct efx_filter_table *table = &state->table[table_id]; + struct efx_filter_spec *saved_spec; + efx_oword_t filter; + int filter_idx, depth; + u32 key; + int rc; + + key = efx_filter_build(&filter, spec); + + spin_lock_bh(&state->lock); + + rc = efx_filter_search(table, spec, key, false, &depth); + if (rc < 0) + goto out; + filter_idx = rc; + saved_spec = &table->spec[filter_idx]; + + if (spec->priority < saved_spec->priority) { + rc = -EPERM; + goto out; + } + + efx_filter_table_clear_entry(efx, table, filter_idx); + if (table->used == 0) + efx_filter_table_reset_search_depth(state, table_id); + rc = 0; + +out: + spin_unlock_bh(&state->lock); + return rc; +} + +/** + * efx_filter_table_clear - remove filters from a table by priority + * @efx: NIC from which to remove the filters + * @table_id: Table from which to remove the filters + * @priority: Maximum priority to remove + */ +void efx_filter_table_clear(struct efx_nic *efx, + enum efx_filter_table_id table_id, + enum efx_filter_priority priority) +{ + struct efx_filter_state *state = efx->filter_state; + struct efx_filter_table *table = &state->table[table_id]; + int filter_idx; + + spin_lock_bh(&state->lock); + + for (filter_idx = 0; filter_idx < table->size; ++filter_idx) + if (table->spec[filter_idx].priority <= priority) + efx_filter_table_clear_entry(efx, table, filter_idx); + if (table->used == 0) + efx_filter_table_reset_search_depth(state, table_id); + + spin_unlock_bh(&state->lock); +} + +/* Restore filter stater after reset */ +void efx_restore_filters(struct efx_nic *efx) +{ + struct efx_filter_state *state = efx->filter_state; + enum efx_filter_table_id table_id; + struct efx_filter_table *table; + efx_oword_t filter; + int filter_idx; + + spin_lock_bh(&state->lock); + + for (table_id = 0; table_id < EFX_FILTER_TABLE_COUNT; table_id++) { + table = &state->table[table_id]; + for (filter_idx = 0; filter_idx < table->size; filter_idx++) { + if (!test_bit(filter_idx, table->used_bitmap)) + continue; + efx_filter_build(&filter, &table->spec[filter_idx]); + efx_writeo(efx, &filter, + table->offset + table->step * filter_idx); + } + } + + efx_filter_push_rx_limits(efx); + + spin_unlock_bh(&state->lock); +} + +int efx_probe_filters(struct efx_nic *efx) +{ + struct efx_filter_state *state; + struct efx_filter_table *table; + unsigned table_id; + + state = kzalloc(sizeof(*efx->filter_state), GFP_KERNEL); + if (!state) + return -ENOMEM; + efx->filter_state = state; + + spin_lock_init(&state->lock); + + if (efx_nic_rev(efx) >= EFX_REV_FALCON_B0) { + table = &state->table[EFX_FILTER_TABLE_RX_IP]; + table->offset = FR_BZ_RX_FILTER_TBL0; + table->size = FR_BZ_RX_FILTER_TBL0_ROWS; + table->step = FR_BZ_RX_FILTER_TBL0_STEP; + } + + if (efx_nic_rev(efx) >= EFX_REV_SIENA_A0) { + table = &state->table[EFX_FILTER_TABLE_RX_MAC]; + table->offset = FR_CZ_RX_MAC_FILTER_TBL0; + table->size = FR_CZ_RX_MAC_FILTER_TBL0_ROWS; + table->step = FR_CZ_RX_MAC_FILTER_TBL0_STEP; + } + + for (table_id = 0; table_id < EFX_FILTER_TABLE_COUNT; table_id++) { + table = &state->table[table_id]; + if (table->size == 0) + continue; + table->used_bitmap = kcalloc(BITS_TO_LONGS(table->size), + sizeof(unsigned long), + GFP_KERNEL); + if (!table->used_bitmap) + goto fail; + table->spec = vmalloc(table->size * sizeof(*table->spec)); + if (!table->spec) + goto fail; + memset(table->spec, 0, table->size * sizeof(*table->spec)); + } + + return 0; + +fail: + efx_remove_filters(efx); + return -ENOMEM; +} + +void efx_remove_filters(struct efx_nic *efx) +{ + struct efx_filter_state *state = efx->filter_state; + enum efx_filter_table_id table_id; + + for (table_id = 0; table_id < EFX_FILTER_TABLE_COUNT; table_id++) { + kfree(state->table[table_id].used_bitmap); + vfree(state->table[table_id].spec); + } + kfree(state); +} |