net/qede/base: fix page index for PBL chains

ecore_chain_set_prod/cons() sets the wrong page index in chains with
non-power of 2 page count. Fix ecore_chain_set_prod/cons() for PBL
chains with non power of 2 page count.
Calculate the right page index according to current indexes.

Fixes: ec94dbc57362 ("qede: add base driver")
Cc: stable@dpdk.org
Signed-off-by: Rasesh Mody <rmody@marvell.com>

diff --git a/drivers/net/qede/base/ecore_chain.h b/drivers/net/qede/base/ecore_chain.h
index 6d0382d..c69920b 100644 (file)
--- a/drivers/net/qede/base/ecore_chain.h
+++ b/drivers/net/qede/base/ecore_chain.h
@@ -86,8 +86,8 @@ struct ecore_chain {
                void            **pp_virt_addr_tbl;
 
                union {
-                       struct ecore_chain_pbl_u16      u16;
-                       struct ecore_chain_pbl_u32      u32;
+                       struct ecore_chain_pbl_u16      pbl_u16;
+                       struct ecore_chain_pbl_u32      pbl_u32;
                } c;
        } pbl;
 
@@ -405,7 +405,7 @@ static OSAL_INLINE void *ecore_chain_produce(struct ecore_chain *p_chain)
                if ((p_chain->u.chain16.prod_idx &
                     p_chain->elem_per_page_mask) == p_chain->next_page_mask) {
                        p_prod_idx = &p_chain->u.chain16.prod_idx;
-                       p_prod_page_idx = &p_chain->pbl.c.u16.prod_page_idx;
+                       p_prod_page_idx = &p_chain->pbl.c.pbl_u16.prod_page_idx;
                        ecore_chain_advance_page(p_chain, &p_chain->p_prod_elem,
                                                 p_prod_idx, p_prod_page_idx);
                }
@@ -414,7 +414,7 @@ static OSAL_INLINE void *ecore_chain_produce(struct ecore_chain *p_chain)
                if ((p_chain->u.chain32.prod_idx &
                     p_chain->elem_per_page_mask) == p_chain->next_page_mask) {
                        p_prod_idx = &p_chain->u.chain32.prod_idx;
-                       p_prod_page_idx = &p_chain->pbl.c.u32.prod_page_idx;
+                       p_prod_page_idx = &p_chain->pbl.c.pbl_u32.prod_page_idx;
                        ecore_chain_advance_page(p_chain, &p_chain->p_prod_elem,
                                                 p_prod_idx, p_prod_page_idx);
                }
@@ -479,7 +479,7 @@ static OSAL_INLINE void *ecore_chain_consume(struct ecore_chain *p_chain)
                if ((p_chain->u.chain16.cons_idx &
                     p_chain->elem_per_page_mask) == p_chain->next_page_mask) {
                        p_cons_idx = &p_chain->u.chain16.cons_idx;
-                       p_cons_page_idx = &p_chain->pbl.c.u16.cons_page_idx;
+                       p_cons_page_idx = &p_chain->pbl.c.pbl_u16.cons_page_idx;
                        ecore_chain_advance_page(p_chain, &p_chain->p_cons_elem,
                                                 p_cons_idx, p_cons_page_idx);
                }
@@ -488,7 +488,7 @@ static OSAL_INLINE void *ecore_chain_consume(struct ecore_chain *p_chain)
                if ((p_chain->u.chain32.cons_idx &
                     p_chain->elem_per_page_mask) == p_chain->next_page_mask) {
                        p_cons_idx = &p_chain->u.chain32.cons_idx;
-                       p_cons_page_idx = &p_chain->pbl.c.u32.cons_page_idx;
+                       p_cons_page_idx = &p_chain->pbl.c.pbl_u32.cons_page_idx;
                        ecore_chain_advance_page(p_chain, &p_chain->p_cons_elem,
                                                 p_cons_idx, p_cons_page_idx);
                }
@@ -532,11 +532,11 @@ static OSAL_INLINE void ecore_chain_reset(struct ecore_chain *p_chain)
                u32 reset_val = p_chain->page_cnt - 1;
 
                if (is_chain_u16(p_chain)) {
-                       p_chain->pbl.c.u16.prod_page_idx = (u16)reset_val;
-                       p_chain->pbl.c.u16.cons_page_idx = (u16)reset_val;
+                       p_chain->pbl.c.pbl_u16.prod_page_idx = (u16)reset_val;
+                       p_chain->pbl.c.pbl_u16.cons_page_idx = (u16)reset_val;
                } else {
-                       p_chain->pbl.c.u32.prod_page_idx = reset_val;
-                       p_chain->pbl.c.u32.cons_page_idx = reset_val;
+                       p_chain->pbl.c.pbl_u32.prod_page_idx = reset_val;
+                       p_chain->pbl.c.pbl_u32.cons_page_idx = reset_val;
                }
        }
 
@@ -725,18 +725,34 @@ static OSAL_INLINE void ecore_chain_set_prod(struct ecore_chain *p_chain,
                                             u32 prod_idx, void *p_prod_elem)
 {
        if (p_chain->mode == ECORE_CHAIN_MODE_PBL) {
-               /* Use "prod_idx-1" since ecore_chain_produce() advances the
-                * page index before the producer index when getting to
-                * "next_page_mask".
+               u32 cur_prod, page_mask, page_cnt, page_diff;
+
+               cur_prod = is_chain_u16(p_chain) ? p_chain->u.chain16.prod_idx
+                                                : p_chain->u.chain32.prod_idx;
+
+               /* Assume that number of elements in a page is power of 2 */
+               page_mask = ~p_chain->elem_per_page_mask;
+
+               /* Use "cur_prod - 1" and "prod_idx - 1" since producer index
+                * reaches the first element of next page before the page index
+                * is incremented. See ecore_chain_produce().
+                * Index wrap around is not a problem because the difference
+                * between current and given producer indexes is always
+                * positive and lower than the chain's capacity.
                 */
-               u32 elem_idx =
-                       (prod_idx - 1 + p_chain->capacity) % p_chain->capacity;
-               u32 page_idx = elem_idx / p_chain->elem_per_page;
+               page_diff = (((cur_prod - 1) & page_mask) -
+                            ((prod_idx - 1) & page_mask)) /
+                           p_chain->elem_per_page;
 
+               page_cnt = ecore_chain_get_page_cnt(p_chain);
                if (is_chain_u16(p_chain))
-                       p_chain->pbl.c.u16.prod_page_idx = (u16)page_idx;
+                       p_chain->pbl.c.pbl_u16.prod_page_idx =
+                               (p_chain->pbl.c.pbl_u16.prod_page_idx -
+                                page_diff + page_cnt) % page_cnt;
                else
-                       p_chain->pbl.c.u32.prod_page_idx = page_idx;
+                       p_chain->pbl.c.pbl_u32.prod_page_idx =
+                               (p_chain->pbl.c.pbl_u32.prod_page_idx -
+                                page_diff + page_cnt) % page_cnt;
        }
 
        if (is_chain_u16(p_chain))
@@ -756,18 +772,34 @@ static OSAL_INLINE void ecore_chain_set_cons(struct ecore_chain *p_chain,
                                             u32 cons_idx, void *p_cons_elem)
 {
        if (p_chain->mode == ECORE_CHAIN_MODE_PBL) {
-               /* Use "cons_idx-1" since ecore_chain_consume() advances the
-                * page index before the consumer index when getting to
-                * "next_page_mask".
+               u32 cur_cons, page_mask, page_cnt, page_diff;
+
+               cur_cons = is_chain_u16(p_chain) ? p_chain->u.chain16.cons_idx
+                                                : p_chain->u.chain32.cons_idx;
+
+               /* Assume that number of elements in a page is power of 2 */
+               page_mask = ~p_chain->elem_per_page_mask;
+
+               /* Use "cur_cons - 1" and "cons_idx - 1" since consumer index
+                * reaches the first element of next page before the page index
+                * is incremented. See ecore_chain_consume().
+                * Index wrap around is not a problem because the difference
+                * between current and given consumer indexes is always
+                * positive and lower than the chain's capacity.
                 */
-               u32 elem_idx =
-                       (cons_idx - 1 + p_chain->capacity) % p_chain->capacity;
-               u32 page_idx = elem_idx / p_chain->elem_per_page;
+               page_diff = (((cur_cons - 1) & page_mask) -
+                            ((cons_idx - 1) & page_mask)) /
+                           p_chain->elem_per_page;
 
+               page_cnt = ecore_chain_get_page_cnt(p_chain);
                if (is_chain_u16(p_chain))
-                       p_chain->pbl.c.u16.cons_page_idx = (u16)page_idx;
+                       p_chain->pbl.c.pbl_u16.cons_page_idx =
+                               (p_chain->pbl.c.pbl_u16.cons_page_idx -
+                                page_diff + page_cnt) % page_cnt;
                else
-                       p_chain->pbl.c.u32.cons_page_idx = page_idx;
+                       p_chain->pbl.c.pbl_u32.cons_page_idx =
+                               (p_chain->pbl.c.pbl_u32.cons_page_idx -
+                                page_diff + page_cnt) % page_cnt;
        }
 
        if (is_chain_u16(p_chain))