From: Benjamin Berg <benjamin.berg@xxxxxxxxx>
Map the pages when allocating them so that we will not need to map each
of the used fragments at a later point.
For now the mapping is not used, this will be changed in a later commit.
Signed-off-by: Benjamin Berg <benjamin.berg@xxxxxxxxx>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@xxxxxxxxx>
Reviewed-by: Johannes Berg <johannes.berg@xxxxxxxxx>
---
.../wireless/intel/iwlwifi/pcie/internal.h | 30 +++++++++-
.../net/wireless/intel/iwlwifi/pcie/tx-gen2.c | 22 ++++++-
drivers/net/wireless/intel/iwlwifi/pcie/tx.c | 60 +++++++++++++++----
3 files changed, 95 insertions(+), 17 deletions(-)
diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/internal.h b/drivers/net/wireless/intel/iwlwifi/pcie/internal.h
index d63c1c284f70..b59de4f80b4b 100644
--- a/drivers/net/wireless/intel/iwlwifi/pcie/internal.h
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/internal.h
@@ -603,6 +603,22 @@ struct iwl_tso_hdr_page {
u8 *pos;
};
+/*
+ * Note that we put this struct *last* in the page. By doing that, we ensure
+ * that no TB referencing this page can trigger the 32-bit boundary hardware
+ * bug.
+ */
+struct iwl_tso_page_info {
+ dma_addr_t dma_addr;
+ struct page *next;
+ refcount_t use_count;
+};
+
+#define IWL_TSO_PAGE_DATA_SIZE (PAGE_SIZE - sizeof(struct iwl_tso_page_info))
+#define IWL_TSO_PAGE_INFO(addr) \
+ ((struct iwl_tso_page_info *)(((unsigned long)addr & PAGE_MASK) + \
+ IWL_TSO_PAGE_DATA_SIZE))
+
int iwl_pcie_tx_init(struct iwl_trans *trans);
void iwl_pcie_tx_start(struct iwl_trans *trans, u32 scd_base_addr);
int iwl_pcie_tx_stop(struct iwl_trans *trans);
@@ -628,8 +644,18 @@ struct sg_table *iwl_pcie_prep_tso(struct iwl_trans *trans, struct sk_buff *skb,
struct iwl_cmd_meta *cmd_meta,
u8 **hdr, unsigned int hdr_room);
-void iwl_pcie_free_tso_page(struct iwl_trans *trans, struct sk_buff *skb,
- struct iwl_cmd_meta *cmd_meta);
+void iwl_pcie_free_tso_pages(struct iwl_trans *trans, struct sk_buff *skb,
+ struct iwl_cmd_meta *cmd_meta);
+
+static inline dma_addr_t iwl_pcie_get_tso_page_phys(void *addr)
+{
+ dma_addr_t res;
+
+ res = IWL_TSO_PAGE_INFO(addr)->dma_addr;
+ res += (unsigned long)addr & ~PAGE_MASK;
+
+ return res;
+}
static inline dma_addr_t
iwl_txq_get_first_tb_dma(struct iwl_txq *txq, int idx)
diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/tx-gen2.c b/drivers/net/wireless/intel/iwlwifi/pcie/tx-gen2.c
index 3dcce6a8da50..10ee2c328458 100644
--- a/drivers/net/wireless/intel/iwlwifi/pcie/tx-gen2.c
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/tx-gen2.c
@@ -19,8 +19,10 @@ static struct page *get_workaround_page(struct iwl_trans *trans,
struct sk_buff *skb)
{
struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
+ struct iwl_tso_page_info *info;
struct page **page_ptr;
struct page *ret;
+ dma_addr_t phys;
page_ptr = (void *)((u8 *)skb->cb + trans_pcie->txqs.page_offs);
@@ -28,8 +30,22 @@ static struct page *get_workaround_page(struct iwl_trans *trans,
if (!ret)
return NULL;
+ info = IWL_TSO_PAGE_INFO(page_address(ret));
+
+ /* Create a DMA mapping for the page */
+ phys = dma_map_page_attrs(trans->dev, ret, 0, PAGE_SIZE,
+ DMA_TO_DEVICE, DMA_ATTR_SKIP_CPU_SYNC);
+ if (unlikely(dma_mapping_error(trans->dev, phys))) {
+ __free_page(ret);
+ return NULL;
+ }
+
+ /* Store physical address and set use count */
+ info->dma_addr = phys;
+ refcount_set(&info->use_count, 1);
+
/* set the chaining pointer to the previous page if there */
- *(void **)((u8 *)page_address(ret) + PAGE_SIZE - sizeof(void *)) = *page_ptr;
+ info->next = *page_ptr;
*page_ptr = ret;
return ret;
@@ -76,7 +92,7 @@ static int iwl_txq_gen2_set_tb_with_wa(struct iwl_trans *trans,
* a new mapping for it so the device will not fail.
*/
- if (WARN_ON(len > PAGE_SIZE - sizeof(void *))) {
+ if (WARN_ON(len > IWL_TSO_PAGE_DATA_SIZE)) {
ret = -ENOBUFS;
goto unmap;
}
@@ -782,7 +798,7 @@ static void iwl_txq_gen2_unmap(struct iwl_trans *trans, int txq_id)
struct sk_buff *skb = txq->entries[idx].skb;
if (!WARN_ON_ONCE(!skb))
- iwl_pcie_free_tso_page(trans, skb, cmd_meta);
+ iwl_pcie_free_tso_pages(trans, skb, cmd_meta);
}
iwl_txq_gen2_free_tfd(trans, txq);
txq->read_ptr = iwl_txq_inc_wrap(trans, txq->read_ptr);
diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/tx.c b/drivers/net/wireless/intel/iwlwifi/pcie/tx.c
index ac545a39ad2a..e00d85866de9 100644
--- a/drivers/net/wireless/intel/iwlwifi/pcie/tx.c
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/tx.c
@@ -209,8 +209,22 @@ static void iwl_pcie_clear_cmd_in_flight(struct iwl_trans *trans)
spin_unlock(&trans_pcie->reg_lock);
}
-void iwl_pcie_free_tso_page(struct iwl_trans *trans, struct sk_buff *skb,
- struct iwl_cmd_meta *cmd_meta)
+static void iwl_pcie_free_and_unmap_tso_page(struct iwl_trans *trans,
+ struct page *page)
+{
+ struct iwl_tso_page_info *info = IWL_TSO_PAGE_INFO(page_address(page));
+
+ /* Decrease internal use count and unmap/free page if needed */
+ if (refcount_dec_and_test(&info->use_count)) {
+ dma_unmap_page(trans->dev, info->dma_addr, PAGE_SIZE,
+ DMA_TO_DEVICE);
+
+ __free_page(page);
+ }
+}
+
+void iwl_pcie_free_tso_pages(struct iwl_trans *trans, struct sk_buff *skb,
+ struct iwl_cmd_meta *cmd_meta)
{
struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
struct page **page_ptr;
@@ -221,10 +235,11 @@ void iwl_pcie_free_tso_page(struct iwl_trans *trans, struct sk_buff *skb,
*page_ptr = NULL;
while (next) {
+ struct iwl_tso_page_info *info;
struct page *tmp = next;
- next = *(void **)((u8 *)page_address(next) + PAGE_SIZE -
- sizeof(void *));
+ info = IWL_TSO_PAGE_INFO(page_address(next));
+ next = info->next;
/* Unmap the scatter gather list that is on the last page */
if (!next && cmd_meta->sg_offset) {
@@ -236,7 +251,7 @@ void iwl_pcie_free_tso_page(struct iwl_trans *trans, struct sk_buff *skb,
dma_unmap_sgtable(trans->dev, sgt, DMA_TO_DEVICE, 0);
}
- __free_page(tmp);
+ iwl_pcie_free_and_unmap_tso_page(trans, tmp);
}
}
@@ -381,7 +396,7 @@ static void iwl_pcie_txq_unmap(struct iwl_trans *trans, int txq_id)
if (WARN_ON_ONCE(!skb))
continue;
- iwl_pcie_free_tso_page(trans, skb, cmd_meta);
+ iwl_pcie_free_tso_pages(trans, skb, cmd_meta);
}
iwl_txq_free_tfd(trans, txq);
txq->read_ptr = iwl_txq_inc_wrap(trans, txq->read_ptr);
@@ -1722,7 +1737,9 @@ static void *iwl_pcie_get_page_hdr(struct iwl_trans *trans,
{
struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
struct iwl_tso_hdr_page *p = this_cpu_ptr(trans_pcie->txqs.tso_hdr_page);
+ struct iwl_tso_page_info *info;
struct page **page_ptr;
+ dma_addr_t phys;
void *ret;
page_ptr = (void *)((u8 *)skb->cb + trans_pcie->txqs.page_offs);
@@ -1743,23 +1760,42 @@ static void *iwl_pcie_get_page_hdr(struct iwl_trans *trans,
*
* (see also get_workaround_page() in tx-gen2.c)
*/
- if (p->pos + len < (u8 *)page_address(p->page) + PAGE_SIZE -
- sizeof(void *))
+ if (((unsigned long)p->pos & ~PAGE_MASK) + len < IWL_TSO_PAGE_DATA_SIZE) {
+ info = IWL_TSO_PAGE_INFO(page_address(ret));
goto out;
+ }
/* We don't have enough room on this page, get a new one. */
- __free_page(p->page);
+ iwl_pcie_free_and_unmap_tso_page(trans, p->page);
alloc:
p->page = alloc_page(GFP_ATOMIC);
if (!p->page)
return NULL;
p->pos = page_address(p->page);
+
+ info = IWL_TSO_PAGE_INFO(page_address(ret));
+
/* set the chaining pointer to NULL */
- *(void **)((u8 *)page_address(p->page) + PAGE_SIZE - sizeof(void *)) = NULL;
+ info->next = NULL;
+
+ /* Create a DMA mapping for the page */
+ phys = dma_map_page_attrs(trans->dev, p->page, 0, PAGE_SIZE,
+ DMA_TO_DEVICE, DMA_ATTR_SKIP_CPU_SYNC);
+ if (unlikely(dma_mapping_error(trans->dev, phys))) {
+ __free_page(p->page);
+ p->page = NULL;
+
+ return NULL;
+ }
+
+ /* Store physical address and set use count */
+ info->dma_addr = phys;
+ refcount_set(&info->use_count, 1);
out:
*page_ptr = p->page;
- get_page(p->page);
+ /* Return an internal reference for the caller */
+ refcount_inc(&info->use_count);
ret = p->pos;
p->pos += len;
@@ -2330,7 +2366,7 @@ void iwl_pcie_reclaim(struct iwl_trans *trans, int txq_id, int ssn,
read_ptr, txq->read_ptr, txq_id))
continue;
- iwl_pcie_free_tso_page(trans, skb, cmd_meta);
+ iwl_pcie_free_tso_pages(trans, skb, cmd_meta);
__skb_queue_tail(skbs, skb);
--
2.34.1
