atm: [he] rewrite buffer handling in receive path

Instead of a fixed list of buffers, use the buffer pool correctly and
keep track of the outstanding buffer indexes using a fixed table.
Resolves reported HBUF_ERR's -- failures due to lack of receive buffers.

Signed-off-by: Chas Williams - CONTRACTOR <chas@cmf.nrl.navy.mil>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 25 insertions, 23 deletions

diff --git a/drivers/atm/he.h b/drivers/atm/he.h
index 8bf3264e5d00..110a27d2ecfc 100644
--- a/drivers/atm/he.h
+++ b/drivers/atm/he.h
@@ -198,26 +198,33 @@ struct he_hsp {
         } group[HE_NUM_GROUPS];
 };
 
-/* figure 2.9 receive buffer pools */
+/*
+ * figure 2.9 receive buffer pools
+ *
+ * since a virtual address might be more than 32 bits, we store an index
+ * in the virt member of he_rbp.  NOTE: the lower six bits in the  rbrq
+ * addr member are used for buffer status further limiting us to 26 bits.
+ */
 
 struct he_rbp {
         volatile u32 phys;
-        volatile u32 status;
+        volatile u32 idx;       /* virt */
 };
 
-/* NOTE: it is suggested that virt be the virtual address of the host
-   buffer.  on a 64-bit machine, this would not work.  Instead, we
-   store the real virtual address in another list, and store an index
-   (and buffer status) in the virt member.
-*/
+#define RBP_IDX_OFFSET 6
+
+/*
+ * the he dma engine will try to hold an extra 16 buffers in its local
+ * caches.  and add a couple buffers for safety.
+ */
 
-#define RBP_INDEX_OFF   6
-#define RBP_INDEX(x)    (((long)(x) >> RBP_INDEX_OFF) & 0xffff)
-#define RBP_LOANED      0x80000000
-#define RBP_SMALLBUF    0x40000000
+#define RBPL_TABLE_SIZE (CONFIG_RBPL_SIZE + 16 + 2)
 
-struct he_virt {
-        void *virt;
+struct he_buff {
+        struct list_head entry;
+        dma_addr_t mapping;
+        unsigned long len;
+        u8 data[];
 };
 
 #ifdef notyet
@@ -286,10 +293,13 @@ struct he_dev {
         struct he_rbrq *rbrq_base, *rbrq_head;
         int rbrq_peak;
 
+        struct he_buff **rbpl_virt;
+        unsigned long *rbpl_table;
+        unsigned long rbpl_hint;
         struct pci_pool *rbpl_pool;
         dma_addr_t rbpl_phys;
         struct he_rbp *rbpl_base, *rbpl_tail;
-        struct he_virt *rbpl_virt;
+        struct list_head rbpl_outstanding;
         int rbpl_peak;
 
         dma_addr_t tbrq_phys;
@@ -304,20 +314,12 @@ struct he_dev {
         struct he_dev *next;
 };
 
-struct he_iovec
-{
-        u32 iov_base;
-        u32 iov_len;
-};
-
 #define HE_MAXIOV 20
 
 struct he_vcc
 {
-        struct he_iovec iov_head[HE_MAXIOV];
-        struct he_iovec *iov_tail;
+        struct list_head buffers;
         int pdu_len;
-
         int rc_index;
 
         wait_queue_head_t rx_waitq;