IB/hfi1: Remove multiple device cdev

hfi1 current exports a cdev that can be used to target all of the hfi's
in the system. However there is a problem with this approach in
that the devices could be on different subnets. This is a problem that
user space can figure out and explicitly tell the driver on which device
to create a context.

Remove the multi-purpose cdev leaving a dedicated cdev for each port.
Also remove the striping capability that is dependent upon the user
choosing the multi-purpose cdev. It is now up to user space to determine
how to stripe contexts.

Reviewed-by: Dean Luick <dean.luick@intel.com>
Reviewed-by: Mitko Haralanov <mitko.haralanov@intel.com>
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

2 files changed, 21 insertions, 100 deletions

diff --git a/drivers/staging/rdma/hfi1/file_ops.c b/drivers/staging/rdma/hfi1/file_ops.c
index c1c5bf82addb..518cd891b63d 100644
--- a/drivers/staging/rdma/hfi1/file_ops.c
+++ b/drivers/staging/rdma/hfi1/file_ops.c
@@ -86,8 +86,7 @@ static int get_ctxt_info(struct file *, void __user *, __u32);
 static int get_base_info(struct file *, void __user *, __u32);
 static int setup_ctxt(struct file *);
 static int setup_subctxt(struct hfi1_ctxtdata *);
-static int get_user_context(struct file *, struct hfi1_user_info *,
-                            int, unsigned);
+static int get_user_context(struct file *, struct hfi1_user_info *, int);
 static int find_shared_ctxt(struct file *, const struct hfi1_user_info *);
 static int allocate_ctxt(struct file *, struct hfi1_devdata *,
                          struct hfi1_user_info *);
@@ -836,7 +835,7 @@ static u64 kvirt_to_phys(void *addr)
 static int assign_ctxt(struct file *fp, struct hfi1_user_info *uinfo)
 {
         int i_minor, ret = 0;
-        unsigned swmajor, swminor, alg = HFI1_ALG_ACROSS;
+        unsigned int swmajor, swminor;
 
         swmajor = uinfo->userversion >> 16;
         if (swmajor != HFI1_USER_SWMAJOR) {
@@ -846,9 +845,6 @@ static int assign_ctxt(struct file *fp, struct hfi1_user_info *uinfo)
 
         swminor = uinfo->userversion & 0xffff;
 
-        if (uinfo->hfi1_alg < HFI1_ALG_COUNT)
-                alg = uinfo->hfi1_alg;
-
         mutex_lock(&hfi1_mutex);
         /* First, lets check if we need to setup a shared context? */
         if (uinfo->subctxt_cnt) {
@@ -868,7 +864,7 @@ static int assign_ctxt(struct file *fp, struct hfi1_user_info *uinfo)
          */
         if (!ret) {
                 i_minor = iminor(file_inode(fp)) - HFI1_USER_MINOR_BASE;
-                ret = get_user_context(fp, uinfo, i_minor - 1, alg);
+                ret = get_user_context(fp, uinfo, i_minor);
         }
 done_unlock:
         mutex_unlock(&hfi1_mutex);
@@ -876,71 +872,26 @@ done:
         return ret;
 }
 
-/* return true if the device available for general use */
-static int usable_device(struct hfi1_devdata *dd)
-{
-        struct hfi1_pportdata *ppd = dd->pport;
-
-        return driver_lstate(ppd) == IB_PORT_ACTIVE;
-}
-
 static int get_user_context(struct file *fp, struct hfi1_user_info *uinfo,
-                            int devno, unsigned alg)
+                            int devno)
 {
         struct hfi1_devdata *dd = NULL;
-        int ret = 0, devmax, npresent, nup, dev;
+        int devmax, npresent, nup;
 
         devmax = hfi1_count_units(&npresent, &nup);
-        if (!npresent) {
-                ret = -ENXIO;
-                goto done;
-        }
-        if (!nup) {
-                ret = -ENETDOWN;
-                goto done;
-        }
-        if (devno >= 0) {
-                dd = hfi1_lookup(devno);
-                if (!dd)
-                        ret = -ENODEV;
-                else if (!dd->freectxts)
-                        ret = -EBUSY;
-        } else {
-                struct hfi1_devdata *pdd;
-
-                if (alg == HFI1_ALG_ACROSS) {
-                        unsigned free = 0U;
-
-                        for (dev = 0; dev < devmax; dev++) {
-                                pdd = hfi1_lookup(dev);
-                                if (!pdd)
-                                        continue;
-                                if (!usable_device(pdd))
-                                        continue;
-                                if (pdd->freectxts &&
-                                    pdd->freectxts > free) {
-                                        dd = pdd;
-                                        free = pdd->freectxts;
-                                }
-                        }
-                } else {
-                        for (dev = 0; dev < devmax; dev++) {
-                                pdd = hfi1_lookup(dev);
-                                if (!pdd)
-                                        continue;
-                                if (!usable_device(pdd))
-                                        continue;
-                                if (pdd->freectxts) {
-                                        dd = pdd;
-                                        break;
-                                }
-                        }
-                }
-                if (!dd)
-                        ret = -EBUSY;
-        }
-done:
-        return ret ? ret : allocate_ctxt(fp, dd, uinfo);
+        if (!npresent)
+                return -ENXIO;
+
+        if (!nup)
+                return -ENETDOWN;
+
+        dd = hfi1_lookup(devno);
+        if (!dd)
+                return -ENODEV;
+        else if (!dd->freectxts)
+                return -EBUSY;
+
+        return allocate_ctxt(fp, dd, uinfo);
 }
 
 static int find_shared_ctxt(struct file *fp,
@@ -1698,15 +1649,8 @@ static const struct file_operations ui_file_ops = {
 #define UI_OFFSET 192   /* device minor offset for UI devices */
 static int create_ui = 1;
 
-static struct cdev wildcard_cdev;
-static struct device *wildcard_device;
-
-static atomic_t user_count = ATOMIC_INIT(0);
-
 static void user_remove(struct hfi1_devdata *dd)
 {
-        if (atomic_dec_return(&user_count) == 0)
-                hfi1_cdev_cleanup(&wildcard_cdev, &wildcard_device);
 
         hfi1_cdev_cleanup(&dd->user_cdev, &dd->user_device);
         hfi1_cdev_cleanup(&dd->ui_cdev, &dd->ui_device);
@@ -1717,16 +1661,8 @@ static int user_add(struct hfi1_devdata *dd)
         char name[10];
         int ret;
 
-        if (atomic_inc_return(&user_count) == 1) {
-                ret = hfi1_cdev_init(0, class_name(), &hfi1_file_ops,
-                                     &wildcard_cdev, &wildcard_device,
-                                     true);
-                if (ret)
-                        goto done;
-        }
-
         snprintf(name, sizeof(name), "%s_%d", class_name(), dd->unit);
-        ret = hfi1_cdev_init(dd->unit + 1, name, &hfi1_file_ops,
+        ret = hfi1_cdev_init(dd->unit, name, &hfi1_file_ops,
                              &dd->user_cdev, &dd->user_device,
                              true);
         if (ret)
diff --git a/include/uapi/rdma/hfi/hfi1_user.h b/include/uapi/rdma/hfi/hfi1_user.h
index a533cecab14f..09558999ca1d 100644
--- a/include/uapi/rdma/hfi/hfi1_user.h
+++ b/include/uapi/rdma/hfi/hfi1_user.h
@@ -75,7 +75,7 @@
  * may not be implemented; the user code must deal with this if it
  * cares, or it must abort after initialization reports the difference.
  */
-#define HFI1_USER_SWMINOR 0
+#define HFI1_USER_SWMINOR 1
 
 /*
  * Set of HW and driver capability/feature bits.
@@ -107,19 +107,6 @@
 #define HFI1_RCVHDR_ENTSIZE_16   (1UL << 1)
 #define HFI1_RCVDHR_ENTSIZE_32   (1UL << 2)
 
-/*
- * If the unit is specified via open, HFI choice is fixed.  If port is
- * specified, it's also fixed.  Otherwise we try to spread contexts
- * across ports and HFIs, using different algorithms.  WITHIN is
- * the old default, prior to this mechanism.
- */
-#define HFI1_ALG_ACROSS 0 /* round robin contexts across HFIs, then
-                          * ports; this is the default */
-#define HFI1_ALG_WITHIN 1 /* use all contexts on an HFI (round robin
-                          * active ports within), then next HFI */
-#define HFI1_ALG_COUNT  2 /* number of algorithm choices */
-
-
 /* User commands. */
 #define HFI1_CMD_ASSIGN_CTXT     1      /* allocate HFI and context */
 #define HFI1_CMD_CTXT_INFO       2      /* find out what resources we got */
@@ -199,9 +186,7 @@ struct hfi1_user_info {
          * Should be set to HFI1_USER_SWVERSION.
          */
         __u32 userversion;
-        __u16 pad;
-        /* HFI selection algorithm, if unit has not selected */
-        __u16 hfi1_alg;
+        __u32 pad;
         /*
          * If two or more processes wish to share a context, each process
          * must set the subcontext_cnt and subcontext_id to the same