mlxsw: spectrum_buffers: Reject overlarge headroom size requests

cap_max_headroom_size holds maximum headroom size supported.
Overstepping that limit might under certain conditions lead to ASIC
freeze.

Query and store the value, and add mlxsw_sp_sb_max_headroom_cells() for
obtaining the stored value. In __mlxsw_sp_port_headroom_set(), reject
requests where the total port buffer is larger than the advertised
maximum.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Petr Machata 2019-02-20 19:32:29 +00:00 committed by David S. Miller
parent edf777f55a
commit bb6c346cef
4 changed files with 31 additions and 1 deletions

View File

@ -26,6 +26,7 @@ enum mlxsw_res_id {
MLXSW_RES_ID_MAX_LAG_MEMBERS,
MLXSW_RES_ID_MAX_BUFFER_SIZE,
MLXSW_RES_ID_CELL_SIZE,
MLXSW_RES_ID_MAX_HEADROOM_SIZE,
MLXSW_RES_ID_ACL_MAX_TCAM_REGIONS,
MLXSW_RES_ID_ACL_MAX_TCAM_RULES,
MLXSW_RES_ID_ACL_MAX_REGIONS,
@ -79,6 +80,7 @@ static u16 mlxsw_res_ids[] = {
[MLXSW_RES_ID_MAX_LAG_MEMBERS] = 0x2521,
[MLXSW_RES_ID_MAX_BUFFER_SIZE] = 0x2802, /* Bytes */
[MLXSW_RES_ID_CELL_SIZE] = 0x2803, /* Bytes */
[MLXSW_RES_ID_MAX_HEADROOM_SIZE] = 0x2811, /* Bytes */
[MLXSW_RES_ID_ACL_MAX_TCAM_REGIONS] = 0x2901,
[MLXSW_RES_ID_ACL_MAX_TCAM_RULES] = 0x2902,
[MLXSW_RES_ID_ACL_MAX_REGIONS] = 0x2903,

View File

@ -852,8 +852,12 @@ int __mlxsw_sp_port_headroom_set(struct mlxsw_sp_port *mlxsw_sp_port, int mtu,
u8 pfc_en = !!my_pfc ? my_pfc->pfc_en : 0;
u16 delay = !!my_pfc ? my_pfc->delay : 0;
char pbmc_pl[MLXSW_REG_PBMC_LEN];
u32 taken_headroom_cells = 0;
u32 max_headroom_cells;
int i, j, err;
max_headroom_cells = mlxsw_sp_sb_max_headroom_cells(mlxsw_sp);
mlxsw_reg_pbmc_pack(pbmc_pl, mlxsw_sp_port->local_port, 0, 0);
err = mlxsw_reg_query(mlxsw_sp->core, MLXSW_REG(pbmc), pbmc_pl);
if (err)
@ -864,6 +868,7 @@ int __mlxsw_sp_port_headroom_set(struct mlxsw_sp_port *mlxsw_sp_port, int mtu,
bool pfc = false;
u16 thres_cells;
u16 delay_cells;
u16 total_cells;
bool lossy;
for (j = 0; j < IEEE_8021QAZ_MAX_TCS; j++) {
@ -881,7 +886,13 @@ int __mlxsw_sp_port_headroom_set(struct mlxsw_sp_port *mlxsw_sp_port, int mtu,
thres_cells = mlxsw_sp_pg_buf_threshold_get(mlxsw_sp, mtu);
delay_cells = mlxsw_sp_pg_buf_delay_get(mlxsw_sp, mtu, delay,
pfc, pause_en);
mlxsw_sp_pg_buf_pack(pbmc_pl, i, thres_cells + delay_cells,
total_cells = thres_cells + delay_cells;
taken_headroom_cells += total_cells;
if (taken_headroom_cells > max_headroom_cells)
return -ENOBUFS;
mlxsw_sp_pg_buf_pack(pbmc_pl, i, total_cells,
thres_cells, lossy);
}

View File

@ -373,6 +373,7 @@ int mlxsw_sp_sb_occ_tc_port_bind_get(struct mlxsw_core_port *mlxsw_core_port,
u32 *p_cur, u32 *p_max);
u32 mlxsw_sp_cells_bytes(const struct mlxsw_sp *mlxsw_sp, u32 cells);
u32 mlxsw_sp_bytes_cells(const struct mlxsw_sp *mlxsw_sp, u32 bytes);
u32 mlxsw_sp_sb_max_headroom_cells(const struct mlxsw_sp *mlxsw_sp);
extern const struct mlxsw_sp_sb_vals mlxsw_sp1_sb_vals;
extern const struct mlxsw_sp_sb_vals mlxsw_sp2_sb_vals;

View File

@ -85,6 +85,7 @@ struct mlxsw_sp_sb {
struct mlxsw_sp_sb_pr *prs;
struct mlxsw_sp_sb_port *ports;
u32 cell_size;
u32 max_headroom_cells;
u64 sb_size;
};
@ -113,6 +114,11 @@ u32 mlxsw_sp_bytes_cells(const struct mlxsw_sp *mlxsw_sp, u32 bytes)
return DIV_ROUND_UP(bytes, mlxsw_sp->sb->cell_size);
}
u32 mlxsw_sp_sb_max_headroom_cells(const struct mlxsw_sp *mlxsw_sp)
{
return mlxsw_sp->sb->max_headroom_cells;
}
static struct mlxsw_sp_sb_pr *mlxsw_sp_sb_pr_get(struct mlxsw_sp *mlxsw_sp,
u16 pool_index)
{
@ -789,6 +795,7 @@ const struct mlxsw_sp_sb_vals mlxsw_sp2_sb_vals = {
int mlxsw_sp_buffers_init(struct mlxsw_sp *mlxsw_sp)
{
u32 max_headroom_size;
u16 ing_pool_count;
u16 eg_pool_count;
int err;
@ -799,12 +806,21 @@ int mlxsw_sp_buffers_init(struct mlxsw_sp *mlxsw_sp)
if (!MLXSW_CORE_RES_VALID(mlxsw_sp->core, MAX_BUFFER_SIZE))
return -EIO;
if (!MLXSW_CORE_RES_VALID(mlxsw_sp->core, MAX_HEADROOM_SIZE))
return -EIO;
mlxsw_sp->sb = kzalloc(sizeof(*mlxsw_sp->sb), GFP_KERNEL);
if (!mlxsw_sp->sb)
return -ENOMEM;
mlxsw_sp->sb->cell_size = MLXSW_CORE_RES_GET(mlxsw_sp->core, CELL_SIZE);
mlxsw_sp->sb->sb_size = MLXSW_CORE_RES_GET(mlxsw_sp->core,
MAX_BUFFER_SIZE);
max_headroom_size = MLXSW_CORE_RES_GET(mlxsw_sp->core,
MAX_HEADROOM_SIZE);
/* Round down, because this limit must not be overstepped. */
mlxsw_sp->sb->max_headroom_cells = max_headroom_size /
mlxsw_sp->sb->cell_size;
err = mlxsw_sp_sb_ports_init(mlxsw_sp);
if (err)
goto err_sb_ports_init;