V4L/DVB (8232): gspca: Change the USERPTR mechanism.

main:     Change the packet copy mechanism for userptr.
          Cannot do reqbufs ioctl when already done and count != 0.
          Accept count < frame size in read().

Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

2 files changed, 52 insertions, 152 deletions

diff --git a/drivers/media/video/gspca/gspca.c b/drivers/media/video/gspca/gspca.c
index cb0aeb0c0a45..77e5e4f4335b 100644
--- a/drivers/media/video/gspca/gspca.c
+++ b/drivers/media/video/gspca/gspca.c
@@ -36,15 +36,14 @@
 #include "gspca.h"
 
 /* global values */
-#define DEF_NURBS 2             /* default number of URBs (mmap) */
-#define USR_NURBS 5             /* default number of URBs (userptr) */
+#define DEF_NURBS 2             /* default number of URBs */
 
 MODULE_AUTHOR("Jean-Francois Moine <http://moinejf.free.fr>");
 MODULE_DESCRIPTION("GSPCA USB Camera Driver");
 MODULE_LICENSE("GPL");
 
-#define DRIVER_VERSION_NUMBER   KERNEL_VERSION(2, 1, 5)
-static const char version[] = "2.1.5";
+#define DRIVER_VERSION_NUMBER   KERNEL_VERSION(2, 1, 6)
+static const char version[] = "2.1.6";
 
 static int video_nr = -1;
 
@@ -153,7 +152,6 @@ static void fill_frame(struct gspca_dev *gspca_dev,
         }
 
         /* resubmit the URB */
-/*fixme: don't do that when userptr and too many URBs sent*/
         urb->status = 0;
         st = usb_submit_urb(urb, GFP_ATOMIC);
         if (st < 0)
@@ -163,18 +161,9 @@ static void fill_frame(struct gspca_dev *gspca_dev,
 /*
  * ISOC message interrupt from the USB device
  *
- * Analyse each packet and call the subdriver for copy
- * to the frame buffer.
- *
- * There are 2 functions:
- *      - the first one (isoc_irq_mmap) is used when the application
- *        buffers are mapped. The frame detection and copy is done
- *        at interrupt level.
- *      - the second one (isoc_irq_user) is used when the application
- *        buffers are in user space (userptr). The frame detection
- *        and copy is done by the application.
+ * Analyse each packet and call the subdriver for copy to the frame buffer.
  */
-static void isoc_irq_mmap(struct urb *urb
+static void isoc_irq(struct urb *urb
 )
 {
         struct gspca_dev *gspca_dev = (struct gspca_dev *) urb->context;
@@ -185,56 +174,11 @@ static void isoc_irq_mmap(struct urb *urb
         fill_frame(gspca_dev, urb);
 }
 
-static void isoc_irq_user(struct urb *urb
-)
-{
-        struct gspca_dev *gspca_dev = (struct gspca_dev *) urb->context;
-        int i;
-
-        PDEBUG(D_PACK, "isoc irq user");
-        if (!gspca_dev->streaming)
-                return;
-
-        i = gspca_dev->urb_in % gspca_dev->nurbs;
-        if (urb != gspca_dev->urb[i]) {
-                PDEBUG(D_ERR|D_PACK, "urb out of sequence");
-                return;                 /* should never occur */
-        }
-
-        gspca_dev->urb_in++;
-        atomic_inc(&gspca_dev->nevent);         /* new event */
-        wake_up_interruptible(&gspca_dev->wq);
-/*fixme: submit a new URBs until urb_in == urb_out (% nurbs)*/
-}
-
-/*
- * treat the isoc messages
- *
- * This routine is called by the application (case userptr).
- */
-static void isoc_transfer(struct gspca_dev *gspca_dev)
-{
-        struct urb *urb;
-        int i;
-
-        for (;;) {
-                i = gspca_dev->urb_out;
-                PDEBUG(D_PACK, "isoc transf i:%d o:%d", gspca_dev->urb_in, i);
-                if (i == gspca_dev->urb_in)     /* isoc message to read */
-                        break;                  /* no (more) message */
-                atomic_dec(&gspca_dev->nevent);
-/*PDEBUG(D_PACK, "isoc_trf nevent: %d", atomic_read(&gspca_dev->nevent));*/
-                gspca_dev->urb_out = i + 1;     /* message treated */
-                urb = gspca_dev->urb[i % gspca_dev->nurbs];
-                fill_frame(gspca_dev, urb);
-        }
-}
-
 /*
  * add data to the current frame
  *
- * This function is called by the subdrivers at interrupt level
- * or user level.
+ * This function is called by the subdrivers at interrupt level.
+ *
  * To build a frame, these ones must add
  *      - one FIRST_PACKET
  *      - 0 or many INTER_PACKETs
@@ -277,16 +221,7 @@ struct gspca_frame *gspca_frame_add(struct gspca_dev *gspca_dev,
                                 frame->v4l2_buf.length);
                         packet_type = DISCARD_PACKET;
                 } else {
-                        if (frame->v4l2_buf.memory != V4L2_MEMORY_USERPTR) {
-                                memcpy(frame->data_end, data, len);
-                        } else {
-                                if (copy_to_user(frame->data_end,
-                                                 data, len) != 0) {
-                                        PDEBUG(D_ERR|D_PACK,
-                                                        "copy to user failed");
-                                        packet_type = DISCARD_PACKET;
-                                }
-                        }
+                        memcpy(frame->data_end, data, len);
                         frame->data_end += len;
                 }
         }
@@ -333,7 +268,6 @@ static void *rvmalloc(unsigned long size)
 /*      size = PAGE_ALIGN(size);        (already done) */
         mem = vmalloc_32(size);
         if (mem != NULL) {
-                memset(mem, 0, size);
                 adr = (unsigned long) mem;
                 while ((long) size > 0) {
                         SetPageReserved(vmalloc_to_page((void *) adr));
@@ -344,14 +278,12 @@ static void *rvmalloc(unsigned long size)
         return mem;
 }
 
-static void rvfree(void *mem, unsigned long size)
+static void rvfree(void *mem, long size)
 {
         unsigned long adr;
 
-        if (!mem)
-                return;
         adr = (unsigned long) mem;
-        while ((long) size > 0) {
+        while (size > 0) {
                 ClearPageReserved(vmalloc_to_page((void *) adr));
                 adr += PAGE_SIZE;
                 size -= PAGE_SIZE;
@@ -370,16 +302,13 @@ static int frame_alloc(struct gspca_dev *gspca_dev,
         frsz = gspca_dev->cam.cam_mode[i].sizeimage;
         PDEBUG(D_STREAM, "frame alloc frsz: %d", frsz);
         frsz = PAGE_ALIGN(frsz);
-        PDEBUG(D_STREAM, "new fr_sz: %d", frsz);
         gspca_dev->frsz = frsz;
         if (count > GSPCA_MAX_FRAMES)
                 count = GSPCA_MAX_FRAMES;
-        if (gspca_dev->memory == V4L2_MEMORY_MMAP) {
-                gspca_dev->frbuf = rvmalloc(frsz * count);
-                if (!gspca_dev->frbuf) {
-                        err("frame alloc failed");
-                        return -ENOMEM;
-                }
+        gspca_dev->frbuf = rvmalloc(frsz * count);
+        if (!gspca_dev->frbuf) {
+                err("frame alloc failed");
+                return -ENOMEM;
         }
         gspca_dev->nframes = count;
         for (i = 0; i < count; i++) {
@@ -391,11 +320,9 @@ static int frame_alloc(struct gspca_dev *gspca_dev,
                 frame->v4l2_buf.length = frsz;
                 frame->v4l2_buf.memory = gspca_dev->memory;
                 frame->v4l2_buf.sequence = 0;
-                if (gspca_dev->memory == V4L2_MEMORY_MMAP) {
-                        frame->data = frame->data_end =
+                frame->data = frame->data_end =
                                         gspca_dev->frbuf + i * frsz;
-                        frame->v4l2_buf.m.offset = i * frsz;
-                }
+                frame->v4l2_buf.m.offset = i * frsz;
         }
         gspca_dev->fr_i = gspca_dev->fr_o = gspca_dev->fr_q = 0;
         gspca_dev->last_packet_type = DISCARD_PACKET;
@@ -509,7 +436,6 @@ static int create_urbs(struct gspca_dev *gspca_dev,
 {
         struct urb *urb;
         int n, nurbs, i, psize, npkt, bsize;
-        usb_complete_t usb_complete;
 
         /* calculate the packet size and the number of packets */
         psize = le16_to_cpu(ep->desc.wMaxPacketSize);
@@ -522,14 +448,7 @@ static int create_urbs(struct gspca_dev *gspca_dev,
         bsize = psize * npkt;
         PDEBUG(D_STREAM,
                 "isoc %d pkts size %d (bsize:%d)", npkt, psize, bsize);
-/*fixme:don't submit all URBs when userptr*/
-        if (gspca_dev->memory != V4L2_MEMORY_USERPTR) {
-                usb_complete = isoc_irq_mmap;
-                nurbs = DEF_NURBS;
-        } else {
-                usb_complete = isoc_irq_user;
-                nurbs = USR_NURBS;
-        }
+        nurbs = DEF_NURBS;
         gspca_dev->nurbs = nurbs;
         for (n = 0; n < nurbs; n++) {
                 urb = usb_alloc_urb(npkt, GFP_KERNEL);
@@ -556,7 +475,7 @@ static int create_urbs(struct gspca_dev *gspca_dev,
                 urb->transfer_flags = URB_ISO_ASAP
                                         | URB_NO_TRANSFER_DMA_MAP;
                 urb->interval = ep->desc.bInterval;
-                urb->complete = usb_complete;
+                urb->complete = isoc_irq;
                 urb->number_of_packets = npkt;
                 urb->transfer_buffer_length = bsize;
                 for (i = 0; i < npkt; i++) {
@@ -564,7 +483,6 @@ static int create_urbs(struct gspca_dev *gspca_dev,
                         urb->iso_frame_desc[i].offset = psize * i;
                 }
         }
-        gspca_dev->urb_in = gspca_dev->urb_out = 0;
         return 0;
 }
 
@@ -1063,6 +981,7 @@ static int vidioc_reqbufs(struct file *file, void *priv,
         if (rb->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
                 return -EINVAL;
         switch (rb->memory) {
+        case GSPCA_MEMORY_READ:
         case V4L2_MEMORY_MMAP:
         case V4L2_MEMORY_USERPTR:
                 break;
@@ -1072,13 +991,6 @@ static int vidioc_reqbufs(struct file *file, void *priv,
         if (mutex_lock_interruptible(&gspca_dev->queue_lock))
                 return -ERESTARTSYS;
 
-        for (i = 0; i < gspca_dev->nframes; i++) {
-                if (gspca_dev->frame[i].vma_use_count) {
-                        ret = -EBUSY;
-                        goto out;
-                }
-        }
-
         /* only one file may do capture */
         if ((gspca_dev->capt_file != NULL && gspca_dev->capt_file != file)
             || gspca_dev->streaming) {
@@ -1086,10 +998,20 @@ static int vidioc_reqbufs(struct file *file, void *priv,
                 goto out;
         }
 
-        if (rb->count == 0) { /* unrequest? */
+        if (rb->count == 0) {                   /* unrequest */
+                for (i = 0; i < gspca_dev->nframes; i++) {
+                        if (gspca_dev->frame[i].vma_use_count) {
+                                ret = -EBUSY;
+                                goto out;
+                        }
+                }
                 frame_free(gspca_dev);
                 gspca_dev->capt_file = NULL;
         } else {
+                if (gspca_dev->nframes != 0) {
+                        ret = -EBUSY;
+                        goto out;
+                }
                 gspca_dev->memory = rb->memory;
                 ret = frame_alloc(gspca_dev, rb->count);
                 if (ret == 0) {
@@ -1301,9 +1223,6 @@ static int dev_mmap(struct file *file, struct vm_area_struct *vma)
         struct page *page;
         unsigned long addr, start, size;
         int i, ret;
-#ifdef CONFIG_VIDEO_V4L1_COMPAT
-        int compat = 0;
-#endif
 
         start = vma->vm_start;
         size = vma->vm_end - vma->vm_start;
@@ -1338,11 +1257,11 @@ static int dev_mmap(struct file *file, struct vm_area_struct *vma)
                 goto out;
         }
 #ifdef CONFIG_VIDEO_V4L1_COMPAT
-        if (i == 0 && size == frame->v4l2_buf.length * gspca_dev->nframes)
-                compat = 1;
-        else
+        /* v4l1 maps all the buffers */
+        if (i != 0
+            || size != frame->v4l2_buf.length * gspca_dev->nframes)
 #endif
-        if (size != frame->v4l2_buf.length) {
+            if (size != frame->v4l2_buf.length) {
                 PDEBUG(D_STREAM, "mmap bad size");
                 ret = -EINVAL;
                 goto out;
@@ -1368,14 +1287,6 @@ static int dev_mmap(struct file *file, struct vm_area_struct *vma)
         vma->vm_ops = &gspca_vm_ops;
         vma->vm_private_data = frame;
         gspca_vm_open(vma);
-#ifdef CONFIG_VIDEO_V4L1_COMPAT
-        if (compat) {
-/*fixme: ugly*/
-                for (i = 1; i < gspca_dev->nframes; ++i)
-                        gspca_dev->frame[i].v4l2_buf.flags |=
-                                                V4L2_BUF_FLAG_MAPPED;
-        }
-#endif
         ret = 0;
 out:
         mutex_unlock(&gspca_dev->queue_lock);
@@ -1393,10 +1304,6 @@ static int frame_wait(struct gspca_dev *gspca_dev,
         struct gspca_frame *frame;
         int i, j, ret;
 
-        /* if userptr, treat the awaiting URBs */
-        if (gspca_dev->memory == V4L2_MEMORY_USERPTR)
-                isoc_transfer(gspca_dev);
-
         /* check if a frame is ready */
         i = gspca_dev->fr_o;
         j = gspca_dev->fr_queue[i];
@@ -1421,8 +1328,6 @@ static int frame_wait(struct gspca_dev *gspca_dev,
                 atomic_dec(&gspca_dev->nevent);
                 if (!gspca_dev->streaming || !gspca_dev->present)
                         return -EIO;
-                if (gspca_dev->memory == V4L2_MEMORY_USERPTR)
-                        isoc_transfer(gspca_dev);
                 i = gspca_dev->fr_o;
                 j = gspca_dev->fr_queue[i];
                 frame = &gspca_dev->frame[j];
@@ -1455,9 +1360,9 @@ static int vidioc_dqbuf(struct file *file, void *priv,
         int i, ret;
 
         PDEBUG(D_FRAM, "dqbuf");
-        if (v4l2_buf->type != V4L2_BUF_TYPE_VIDEO_CAPTURE
-            || (v4l2_buf->memory != V4L2_MEMORY_MMAP
-                && v4l2_buf->memory != V4L2_MEMORY_USERPTR))
+        if (v4l2_buf->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
+                return -EINVAL;
+        if (v4l2_buf->memory != gspca_dev->memory)
                 return -EINVAL;
         if (!gspca_dev->streaming)
                 return -EINVAL;
@@ -1475,6 +1380,16 @@ static int vidioc_dqbuf(struct file *file, void *priv,
                 goto out;
         i = ret;                                /* frame index */
         frame = &gspca_dev->frame[i];
+        if (gspca_dev->memory == V4L2_MEMORY_USERPTR) {
+                if (copy_to_user((__u8 *) frame->v4l2_buf.m.userptr,
+                                 frame->data,
+                                 frame->v4l2_buf.bytesused)) {
+                        PDEBUG(D_ERR|D_STREAM,
+                                "dqbuf cp to user failed");
+                        ret = -EFAULT;
+                        goto out;
+                }
+        }
         frame->v4l2_buf.flags &= ~V4L2_BUF_FLAG_DONE;
         memcpy(v4l2_buf, &frame->v4l2_buf, sizeof *v4l2_buf);
         PDEBUG(D_FRAM, "dqbuf %d", i);
@@ -1529,8 +1444,6 @@ static int vidioc_qbuf(struct file *file, void *priv,
 /*      frame->v4l2_buf.flags &= ~V4L2_BUF_FLAG_DONE; */
 
         if (frame->v4l2_buf.memory == V4L2_MEMORY_USERPTR) {
-                frame->data = frame->data_end =
-                                (__u8 *) v4l2_buf->m.userptr;
                 frame->v4l2_buf.m.userptr = v4l2_buf->m.userptr;
                 frame->v4l2_buf.length = v4l2_buf->length;
         }
@@ -1568,7 +1481,7 @@ static int read_alloc(struct gspca_dev *gspca_dev,
                 memset(&rb, 0, sizeof rb);
                 rb.count = gspca_dev->nbufread;
                 rb.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
-                rb.memory = V4L2_MEMORY_MMAP;
+                rb.memory = GSPCA_MEMORY_READ;
                 ret = vidioc_reqbufs(file, gspca_dev, &rb);
                 if (ret != 0) {
                         PDEBUG(D_STREAM, "read reqbuf err %d", ret);
@@ -1576,7 +1489,7 @@ static int read_alloc(struct gspca_dev *gspca_dev,
                 }
                 memset(&v4l2_buf, 0, sizeof v4l2_buf);
                 v4l2_buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
-                v4l2_buf.memory = V4L2_MEMORY_MMAP;
+                v4l2_buf.memory = GSPCA_MEMORY_READ;
                 for (i = 0; i < gspca_dev->nbufread; i++) {
                         v4l2_buf.index = i;
 /*fixme: ugly!*/
@@ -1629,11 +1542,6 @@ static unsigned int dev_poll(struct file *file, poll_table *wait)
                 goto out;
         }
 
-        /* if userptr, treat the awaiting URBs */
-        if (gspca_dev->memory == V4L2_MEMORY_USERPTR
-            && gspca_dev->capt_file == file)
-                isoc_transfer(gspca_dev);
-
         i = gspca_dev->fr_o;
         i = gspca_dev->fr_queue[i];
         if (gspca_dev->frame[i].v4l2_buf.flags & V4L2_BUF_FLAG_DONE)
@@ -1678,7 +1586,7 @@ static ssize_t dev_read(struct file *file, char __user *data,
         for (;;) {
                 memset(&v4l2_buf, 0, sizeof v4l2_buf);
                 v4l2_buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
-                v4l2_buf.memory = V4L2_MEMORY_MMAP;
+                v4l2_buf.memory = GSPCA_MEMORY_READ;
                 ret = vidioc_dqbuf(file, gspca_dev, &v4l2_buf);
                 if (ret != 0) {
                         PDEBUG(D_STREAM, "read dqbuf err %d", ret);
@@ -1700,14 +1608,8 @@ static ssize_t dev_read(struct file *file, char __user *data,
         }
 
         /* copy the frame */
-        if (count < frame->v4l2_buf.bytesused) {
-                PDEBUG(D_STREAM, "read bad count: %d < %d",
-                        count, frame->v4l2_buf.bytesused);
-/*fixme: special errno?*/
-                ret = -EINVAL;
-                goto out;
-        }
-        count = frame->v4l2_buf.bytesused;
+        if (count > frame->v4l2_buf.bytesused)
+                count = frame->v4l2_buf.bytesused;
         ret = copy_to_user(data, frame->data, count);
         if (ret != 0) {
                 PDEBUG(D_ERR|D_STREAM,
diff --git a/drivers/media/video/gspca/gspca.h b/drivers/media/video/gspca/gspca.h
index 945f1ab4c9eb..9b645af81a07 100644
--- a/drivers/media/video/gspca/gspca.h
+++ b/drivers/media/video/gspca/gspca.h
@@ -156,8 +156,6 @@ struct gspca_dev {
         char nbufread;                  /* number of buffers for read() */
         char nurbs;                     /* number of allocated URBs */
         char memory;                    /* memory type (V4L2_MEMORY_xxx) */
-        __u8 urb_in;                    /* URB pointers - used when !mmap */
-        __u8 urb_out;
         __u8 nbalt;                     /* number of USB alternate settings */
 };