IB/ipath: Driver support for userspace sharing of HW contexts

This allows multiple userspace processes to share a single hardware
context in a master/slave arrangement.  It is backwards binary compatible
with existing userspace.

Signed-off-by: Bryan O'Sullivan <bryan.osullivan@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 36 insertions, 9 deletions

diff --git a/drivers/infiniband/hw/ipath/ipath_common.h b/drivers/infiniband/hw/ipath/ipath_common.h
index f577905e3aca..46b7b20d8a91 100644
--- a/drivers/infiniband/hw/ipath/ipath_common.h
+++ b/drivers/infiniband/hw/ipath/ipath_common.h
@@ -185,6 +185,7 @@ typedef enum _ipath_ureg {
 #define IPATH_RUNTIME_PCIE      0x2
 #define IPATH_RUNTIME_FORCE_WC_ORDER    0x4
 #define IPATH_RUNTIME_RCVHDR_COPY       0x8
+#define IPATH_RUNTIME_MASTER    0x10
 
 /*
  * This structure is returned by ipath_userinit() immediately after
@@ -202,7 +203,8 @@ struct ipath_base_info {
         /* version of software, for feature checking. */
         __u32 spi_sw_version;
         /* InfiniPath port assigned, goes into sent packets */
-        __u32 spi_port;
+        __u16 spi_port;
+        __u16 spi_subport;
         /*
          * IB MTU, packets IB data must be less than this.
          * The MTU is in bytes, and will be a multiple of 4 bytes.
@@ -218,7 +220,7 @@ struct ipath_base_info {
         __u32 spi_tidcnt;
         /* size of the TID Eager list in infinipath, in entries */
         __u32 spi_tidegrcnt;
-        /* size of a single receive header queue entry. */
+        /* size of a single receive header queue entry in words. */
         __u32 spi_rcvhdrent_size;
         /*
          * Count of receive header queue entries allocated.
@@ -310,6 +312,12 @@ struct ipath_base_info {
         __u32 spi_filler_for_align;
         /* address of readonly memory copy of the rcvhdrq tail register. */
         __u64 spi_rcvhdr_tailaddr;
+
+        /* shared memory pages for subports if IPATH_RUNTIME_MASTER is set */
+        __u64 spi_subport_uregbase;
+        __u64 spi_subport_rcvegrbuf;
+        __u64 spi_subport_rcvhdr_base;
+
 } __attribute__ ((aligned(8)));
 
 
@@ -328,12 +336,12 @@ struct ipath_base_info {
 
 /*
  * Minor version differences are always compatible
- * a within a major version, however if if user software is larger
+ * a within a major version, however if user software is larger
  * than driver software, some new features and/or structure fields
  * may not be implemented; the user code must deal with this if it
- * cares, or it must abort after initialization reports the difference
+ * cares, or it must abort after initialization reports the difference.
  */
-#define IPATH_USER_SWMINOR 2
+#define IPATH_USER_SWMINOR 3
 
 #define IPATH_USER_SWVERSION ((IPATH_USER_SWMAJOR<<16) | IPATH_USER_SWMINOR)
 
@@ -379,7 +387,16 @@ struct ipath_user_info {
          */
         __u32 spu_rcvhdrsize;
 
-        __u64 spu_unused; /* kept for compatible layout */
+        /*
+         * If two or more processes wish to share a port, each process
+         * must set the spu_subport_cnt and spu_subport_id to the same
+         * values.  The only restriction on the spu_subport_id is that
+         * it be unique for a given node.
+         */
+        __u16 spu_subport_cnt;
+        __u16 spu_subport_id;
+
+        __u32 spu_unused; /* kept for compatible layout */
 
         /*
          * address of struct base_info to write to
@@ -398,13 +415,17 @@ struct ipath_user_info {
 #define IPATH_CMD_TID_UPDATE    19      /* update expected TID entries */
 #define IPATH_CMD_TID_FREE      20      /* free expected TID entries */
 #define IPATH_CMD_SET_PART_KEY  21      /* add partition key */
+#define IPATH_CMD_SLAVE_INFO    22      /* return info on slave processes */
 
-#define IPATH_CMD_MAX           21
+#define IPATH_CMD_MAX           22
 
 struct ipath_port_info {
         __u32 num_active;       /* number of active units */
         __u32 unit;             /* unit (chip) assigned to caller */
-        __u32 port;             /* port on unit assigned to caller */
+        __u16 port;             /* port on unit assigned to caller */
+        __u16 subport;          /* subport on unit assigned to caller */
+        __u16 num_ports;        /* number of ports available on unit */
+        __u16 num_subports;     /* number of subport slaves opened on port */
 };
 
 struct ipath_tid_info {
@@ -435,6 +456,8 @@ struct ipath_cmd {
                 __u32 recv_ctrl;
                 /* partition key to set */
                 __u16 part_key;
+                /* user address of __u32 bitmask of active slaves */
+                __u64 slave_mask_addr;
         } cmd;
 };
 
@@ -596,6 +619,10 @@ struct infinipath_counters {
 
 /* K_PktFlags bits */
 #define INFINIPATH_KPF_INTR 0x1
+#define INFINIPATH_KPF_SUBPORT_MASK 0x3
+#define INFINIPATH_KPF_SUBPORT_SHIFT 1
+
+#define INFINIPATH_MAX_SUBPORT  4
 
 /* SendPIO per-buffer control */
 #define INFINIPATH_SP_TEST    0x40
@@ -610,7 +637,7 @@ struct ipath_header {
         /*
          * Version - 4 bits, Port - 4 bits, TID - 10 bits and Offset -
          * 14 bits before ECO change ~28 Dec 03.  After that, Vers 4,
-         * Port 3, TID 11, offset 14.
+         * Port 4, TID 11, offset 13.
          */
         __le32 ver_port_tid_offset;
         __le16 chksum;