[PATCH] UHCI: use one QH per endpoint, not per URB

This patch (as623) changes the uhci-hcd driver to make it use one QH per
device endpoint, instead of a QH per URB as it does now.  Numerous areas
of the code are affected by this.  For example, the distinction between
"queued" URBs and non-"queued" URBs no longer exists; all URBs belong to
a queue and some just happen to be at the queue's head.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 92 insertions, 228 deletions

diff --git a/drivers/usb/host/uhci-debug.c b/drivers/usb/host/uhci-debug.c
index 5832953086f8..3faccbd68547 100644
--- a/drivers/usb/host/uhci-debug.c
+++ b/drivers/usb/host/uhci-debug.c
@@ -90,13 +90,60 @@ static int uhci_show_td(struct uhci_td *td, char *buf, int len, int space)
         return out - buf;
 }
 
-static int uhci_show_qh(struct uhci_qh *qh, char *buf, int len, int space)
+static int uhci_show_urbp(struct urb_priv *urbp, char *buf, int len, int space)
 {
         char *out = buf;
-        struct urb_priv *urbp;
-        struct list_head *head, *tmp;
         struct uhci_td *td;
-        int i = 0, checked = 0, prevactive = 0;
+        int i, nactive, ninactive;
+
+        if (len < 200)
+                return 0;
+
+        out += sprintf(out, "urb_priv [%p] ", urbp);
+        out += sprintf(out, "urb [%p] ", urbp->urb);
+        out += sprintf(out, "qh [%p] ", urbp->qh);
+        out += sprintf(out, "Dev=%d ", usb_pipedevice(urbp->urb->pipe));
+        out += sprintf(out, "EP=%x(%s) ", usb_pipeendpoint(urbp->urb->pipe),
+                        (usb_pipein(urbp->urb->pipe) ? "IN" : "OUT"));
+
+        switch (usb_pipetype(urbp->urb->pipe)) {
+        case PIPE_ISOCHRONOUS: out += sprintf(out, "ISO"); break;
+        case PIPE_INTERRUPT: out += sprintf(out, "INT"); break;
+        case PIPE_BULK: out += sprintf(out, "BLK"); break;
+        case PIPE_CONTROL: out += sprintf(out, "CTL"); break;
+        }
+
+        out += sprintf(out, "%s", (urbp->fsbr ? " FSBR" : ""));
+        out += sprintf(out, "%s", (urbp->fsbr_timeout ? " FSBR_TO" : ""));
+
+        if (urbp->urb->status != -EINPROGRESS)
+                out += sprintf(out, " Status=%d", urbp->urb->status);
+        out += sprintf(out, "\n");
+
+        i = nactive = ninactive = 0;
+        list_for_each_entry(td, &urbp->td_list, list) {
+                if (++i <= 10 || debug > 2) {
+                        out += sprintf(out, "%*s%d: ", space + 2, "", i);
+                        out += uhci_show_td(td, out, len - (out - buf), 0);
+                } else {
+                        if (td_status(td) & TD_CTRL_ACTIVE)
+                                ++nactive;
+                        else
+                                ++ninactive;
+                }
+        }
+        if (nactive + ninactive > 0)
+                out += sprintf(out, "%*s[skipped %d inactive and %d active "
+                                "TDs]\n",
+                                space, "", ninactive, nactive);
+
+        return out - buf;
+}
+
+static int uhci_show_qh(struct uhci_qh *qh, char *buf, int len, int space)
+{
+        char *out = buf;
+        int i, nurbs;
         __le32 element = qh_element(qh);
 
         /* Try to make sure there's enough memory */
@@ -118,86 +165,36 @@ static int uhci_show_qh(struct uhci_qh *qh, char *buf, int len, int space)
         if (!(element & ~(UHCI_PTR_QH | UHCI_PTR_DEPTH)))
                 out += sprintf(out, "%*s  Element is NULL (bug?)\n", space, "");
 
-        if (!qh->urbp) {
-                out += sprintf(out, "%*s  urbp == NULL\n", space, "");
-                goto out;
-        }
-
-        urbp = qh->urbp;
-
-        head = &urbp->td_list;
-        tmp = head->next;
-
-        td = list_entry(tmp, struct uhci_td, list);
-
-        if (cpu_to_le32(td->dma_handle) != (element & ~UHCI_PTR_BITS))
-                out += sprintf(out, "%*s Element != First TD\n", space, "");
-
-        while (tmp != head) {
-                struct uhci_td *td = list_entry(tmp, struct uhci_td, list);
-
-                tmp = tmp->next;
-
-                out += sprintf(out, "%*s%d: ", space + 2, "", i++);
-                out += uhci_show_td(td, out, len - (out - buf), 0);
-
-                if (i > 10 && !checked && prevactive && tmp != head &&
-                    debug <= 2) {
-                        struct list_head *ntmp = tmp;
-                        struct uhci_td *ntd = td;
-                        int active = 1, ni = i;
-
-                        checked = 1;
-
-                        while (ntmp != head && ntmp->next != head && active) {
-                                ntd = list_entry(ntmp, struct uhci_td, list);
-
-                                ntmp = ntmp->next;
-
-                                active = td_status(ntd) & TD_CTRL_ACTIVE;
-
-                                ni++;
-                        }
-
-                        if (active && ni > i) {
-                                out += sprintf(out, "%*s[skipped %d active TDs]\n", space, "", ni - i);
-                                tmp = ntmp;
-                                td = ntd;
-                                i = ni;
-                        }
+        if (list_empty(&qh->queue)) {
+                out += sprintf(out, "%*s  queue is empty\n", space, "");
+        } else {
+                struct urb_priv *urbp = list_entry(qh->queue.next,
+                                struct urb_priv, node);
+                struct uhci_td *td = list_entry(urbp->td_list.next,
+                                struct uhci_td, list);
+
+                if (cpu_to_le32(td->dma_handle) != (element & ~UHCI_PTR_BITS))
+                        out += sprintf(out, "%*s Element != First TD\n",
+                                        space, "");
+                i = nurbs = 0;
+                list_for_each_entry(urbp, &qh->queue, node) {
+                        if (++i <= 10)
+                                out += uhci_show_urbp(urbp, out,
+                                                len - (out - buf), space + 2);
+                        else
+                                ++nurbs;
                 }
-
-                prevactive = td_status(td) & TD_CTRL_ACTIVE;
-        }
-
-        if (list_empty(&urbp->queue_list) || urbp->queued)
-                goto out;
-
-        out += sprintf(out, "%*sQueued QHs:\n", -space, "--");
-
-        head = &urbp->queue_list;
-        tmp = head->next;
-
-        while (tmp != head) {
-                struct urb_priv *nurbp = list_entry(tmp, struct urb_priv,
-                                                queue_list);
-                tmp = tmp->next;
-
-                out += uhci_show_qh(nurbp->qh, out, len - (out - buf), space);
+                if (nurbs > 0)
+                        out += sprintf(out, "%*s Skipped %d URBs\n",
+                                        space, "", nurbs);
         }
 
-out:
         return out - buf;
 }
 
-#define show_frame_num()        \
-        if (!shown) {           \
-          shown = 1;            \
-          out += sprintf(out, "- Frame %d\n", i); \
-        }
-
 #ifdef CONFIG_PROC_FS
 static const char * const qh_names[] = {
+  "skel_unlink_qh", "skel_iso_qh",
   "skel_int128_qh", "skel_int64_qh",
   "skel_int32_qh", "skel_int16_qh",
   "skel_int8_qh", "skel_int4_qh",
@@ -206,12 +203,6 @@ static const char * const qh_names[] = {
   "skel_bulk_qh", "skel_term_qh"
 };
 
-#define show_qh_name()          \
-        if (!shown) {           \
-          shown = 1;            \
-          out += sprintf(out, "- %s\n", qh_names[i]); \
-        }
-
 static int uhci_show_sc(int port, unsigned short status, char *buf, int len)
 {
         char *out = buf;
@@ -321,139 +312,29 @@ static int uhci_show_status(struct uhci_hcd *uhci, char *buf, int len)
         return out - buf;
 }
 
-static int uhci_show_urbp(struct uhci_hcd *uhci, struct urb_priv *urbp, char *buf, int len)
-{
-        struct list_head *tmp;
-        char *out = buf;
-        int count = 0;
-
-        if (len < 200)
-                return 0;
-
-        out += sprintf(out, "urb_priv [%p] ", urbp);
-        out += sprintf(out, "urb [%p] ", urbp->urb);
-        out += sprintf(out, "qh [%p] ", urbp->qh);
-        out += sprintf(out, "Dev=%d ", usb_pipedevice(urbp->urb->pipe));
-        out += sprintf(out, "EP=%x(%s) ", usb_pipeendpoint(urbp->urb->pipe), (usb_pipein(urbp->urb->pipe) ? "IN" : "OUT"));
-
-        switch (usb_pipetype(urbp->urb->pipe)) {
-        case PIPE_ISOCHRONOUS: out += sprintf(out, "ISO "); break;
-        case PIPE_INTERRUPT: out += sprintf(out, "INT "); break;
-        case PIPE_BULK: out += sprintf(out, "BLK "); break;
-        case PIPE_CONTROL: out += sprintf(out, "CTL "); break;
-        }
-
-        out += sprintf(out, "%s", (urbp->fsbr ? "FSBR " : ""));
-        out += sprintf(out, "%s", (urbp->fsbr_timeout ? "FSBR_TO " : ""));
-
-        if (urbp->urb->status != -EINPROGRESS)
-                out += sprintf(out, "Status=%d ", urbp->urb->status);
-        //out += sprintf(out, "FSBRtime=%lx ",urbp->fsbrtime);
-
-        count = 0;
-        list_for_each(tmp, &urbp->td_list)
-                count++;
-        out += sprintf(out, "TDs=%d ",count);
-
-        if (urbp->queued)
-                out += sprintf(out, "queued\n");
-        else {
-                count = 0;
-                list_for_each(tmp, &urbp->queue_list)
-                        count++;
-                out += sprintf(out, "queued URBs=%d\n", count);
-        }
-
-        return out - buf;
-}
-
-static int uhci_show_lists(struct uhci_hcd *uhci, char *buf, int len)
-{
-        char *out = buf;
-        struct list_head *head, *tmp;
-        int count;
-
-        out += sprintf(out, "Main list URBs:");
-        if (list_empty(&uhci->urb_list))
-                out += sprintf(out, " Empty\n");
-        else {
-                out += sprintf(out, "\n");
-                count = 0;
-                head = &uhci->urb_list;
-                tmp = head->next;
-                while (tmp != head) {
-                        struct urb_priv *urbp = list_entry(tmp, struct urb_priv, urb_list);
-
-                        out += sprintf(out, "  %d: ", ++count);
-                        out += uhci_show_urbp(uhci, urbp, out, len - (out - buf));
-                        tmp = tmp->next;
-                }
-        }
-
-        out += sprintf(out, "Remove list URBs:");
-        if (list_empty(&uhci->urb_remove_list))
-                out += sprintf(out, " Empty\n");
-        else {
-                out += sprintf(out, "\n");
-                count = 0;
-                head = &uhci->urb_remove_list;
-                tmp = head->next;
-                while (tmp != head) {
-                        struct urb_priv *urbp = list_entry(tmp, struct urb_priv, urb_list);
-
-                        out += sprintf(out, "  %d: ", ++count);
-                        out += uhci_show_urbp(uhci, urbp, out, len - (out - buf));
-                        tmp = tmp->next;
-                }
-        }
-
-        out += sprintf(out, "Complete list URBs:");
-        if (list_empty(&uhci->complete_list))
-                out += sprintf(out, " Empty\n");
-        else {
-                out += sprintf(out, "\n");
-                count = 0;
-                head = &uhci->complete_list;
-                tmp = head->next;
-                while (tmp != head) {
-                        struct urb_priv *urbp = list_entry(tmp, struct urb_priv, urb_list);
-
-                        out += sprintf(out, "  %d: ", ++count);
-                        out += uhci_show_urbp(uhci, urbp, out, len - (out - buf));
-                        tmp = tmp->next;
-                }
-        }
-
-        return out - buf;
-}
-
 static int uhci_sprint_schedule(struct uhci_hcd *uhci, char *buf, int len)
 {
-        unsigned long flags;
         char *out = buf;
         int i, j;
         struct uhci_qh *qh;
         struct uhci_td *td;
         struct list_head *tmp, *head;
 
-        spin_lock_irqsave(&uhci->lock, flags);
-
         out += uhci_show_root_hub_state(uhci, out, len - (out - buf));
         out += sprintf(out, "HC status\n");
         out += uhci_show_status(uhci, out, len - (out - buf));
+        if (debug <= 1)
+                return out - buf;
 
         out += sprintf(out, "Frame List\n");
         for (i = 0; i < UHCI_NUMFRAMES; ++i) {
-                int shown = 0;
                 td = uhci->frame_cpu[i];
                 if (!td)
                         continue;
 
-                if (td->dma_handle != (dma_addr_t)uhci->frame[i]) {
-                        show_frame_num();
+                out += sprintf(out, "- Frame %d\n", i); \
+                if (td->dma_handle != (dma_addr_t)uhci->frame[i])
                         out += sprintf(out, "    frame list does not match td->dma_handle!\n");
-                }
-                show_frame_num();
 
                 head = &td->fl_list;
                 tmp = head;
@@ -467,14 +348,11 @@ static int uhci_sprint_schedule(struct uhci_hcd *uhci, char *buf, int len)
         out += sprintf(out, "Skeleton QHs\n");
 
         for (i = 0; i < UHCI_NUM_SKELQH; ++i) {
-                int shown = 0;
+                int cnt = 0;
 
                 qh = uhci->skelqh[i];
-
-                if (debug > 1) {
-                        show_qh_name();
-                        out += uhci_show_qh(qh, out, len - (out - buf), 4);
-                }
+                out += sprintf(out, "- %s\n", qh_names[i]); \
+                out += uhci_show_qh(qh, out, len - (out - buf), 4);
 
                 /* Last QH is the Terminating QH, it's different */
                 if (i == UHCI_NUM_SKELQH - 1) {
@@ -487,44 +365,27 @@ static int uhci_sprint_schedule(struct uhci_hcd *uhci, char *buf, int len)
                         continue;
                 }
 
-                j = (i < 7) ? 7 : i+1;          /* Next skeleton */
-                if (list_empty(&qh->list)) {
-                        if (i < UHCI_NUM_SKELQH - 1) {
-                                if (qh->link !=
-                                    (cpu_to_le32(uhci->skelqh[j]->dma_handle) | UHCI_PTR_QH)) {
-                                        show_qh_name();
-                                        out += sprintf(out, "    skeleton QH not linked to next skeleton QH!\n");
-                                }
-                        }
-
-                        continue;
-                }
-
-                show_qh_name();
-
-                head = &qh->list;
+                j = (i < 9) ? 9 : i+1;          /* Next skeleton */
+                head = &qh->node;
                 tmp = head->next;
 
                 while (tmp != head) {
-                        qh = list_entry(tmp, struct uhci_qh, list);
-
+                        qh = list_entry(tmp, struct uhci_qh, node);
                         tmp = tmp->next;
-
-                        out += uhci_show_qh(qh, out, len - (out - buf), 4);
+                        if (++cnt <= 10)
+                                out += uhci_show_qh(qh, out,
+                                                len - (out - buf), 4);
                 }
+                if ((cnt -= 10) > 0)
+                        out += sprintf(out, "    Skipped %d QHs\n", cnt);
 
-                if (i < UHCI_NUM_SKELQH - 1) {
+                if (i > 1 && i < UHCI_NUM_SKELQH - 1) {
                         if (qh->link !=
                             (cpu_to_le32(uhci->skelqh[j]->dma_handle) | UHCI_PTR_QH))
                                 out += sprintf(out, "    last QH not linked to next skeleton!\n");
                 }
         }
 
-        if (debug > 2)
-                out += uhci_show_lists(uhci, out, len - (out - buf));
-
-        spin_unlock_irqrestore(&uhci->lock, flags);
-
         return out - buf;
 }
 
@@ -541,6 +402,7 @@ static int uhci_debug_open(struct inode *inode, struct file *file)
         struct uhci_hcd *uhci = inode->u.generic_ip;
         struct uhci_debug *up;
         int ret = -ENOMEM;
+        unsigned long flags;
 
         lock_kernel();
         up = kmalloc(sizeof(*up), GFP_KERNEL);
@@ -553,7 +415,9 @@ static int uhci_debug_open(struct inode *inode, struct file *file)
                 goto out;
         }
 
+        spin_lock_irqsave(&uhci->lock, flags);
         up->size = uhci_sprint_schedule(uhci, up->data, MAX_OUTPUT);
+        spin_unlock_irqrestore(&uhci->lock, flags);
 
         file->private_data = up;