]> pilppa.com Git - linux-2.6-omap-h63xx.git/commitdiff
V4L/DVB (6254): Add videobuf-vmalloc
authorMauro Carvalho Chehab <mchehab@infradead.org>
Fri, 3 Aug 2007 02:31:33 +0000 (23:31 -0300)
committerMauro Carvalho Chehab <mchehab@infradead.org>
Wed, 10 Oct 2007 01:14:56 +0000 (22:14 -0300)
Adds a newer videobuf-vmalloc module. This module uses the same
videobuf controls, but implements memory allocation based on vmalloc
methods.

With this method, an USB driver can use video-buf, without needing to
request memory from the DMA-safe area.

Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
drivers/media/Kconfig
drivers/media/video/Kconfig
drivers/media/video/Makefile
drivers/media/video/videobuf-vmalloc.c [new file with mode: 0644]
include/media/videobuf-vmalloc.h [new file with mode: 0644]

index 28ee65c53917db49527a05af2a56a03a807eb14f..fc3ea4c67ccbfdaefa6bcd6f859932fa30f67112 100644 (file)
@@ -134,6 +134,10 @@ config VIDEOBUF_DMA_SG
        select VIDEOBUF_GEN
        tristate
 
+config VIDEOBUF_VMALLOC
+       select VIDEOBUF_GEN
+       tristate
+
 config VIDEO_BUF_DVB
        tristate
 
index c4f424422f700eac0d307706da89ebbb51718604..2e571eb9313ae6d5b8e49b5829c83ec8a590c354 100644 (file)
@@ -364,7 +364,7 @@ endmenu # encoder / decoder chips
 config VIDEO_VIVI
        tristate "Virtual Video Driver"
        depends on VIDEO_V4L2 && !SPARC32 && !SPARC64 && PCI
-       select VIDEOBUF_DMA_SG
+       select VIDEOBUF_VMALLOC
        default n
        ---help---
          Enables a virtual video driver. This device shows a color bar
index cb300241eb8991f8b700b60a7bf095b9d617a4f9..c8140aec1a16995e87ab3190b22ec80d7178f4e8 100644 (file)
@@ -89,6 +89,7 @@ obj-$(CONFIG_TUNER_TEA5761) += tea5761.o
 
 obj-$(CONFIG_VIDEOBUF_GEN) += videobuf-core.o
 obj-$(CONFIG_VIDEOBUF_DMA_SG) += videobuf-dma-sg.o
+obj-$(CONFIG_VIDEOBUF_VMALLOC) += videobuf-vmalloc.o
 obj-$(CONFIG_VIDEO_BUF_DVB) += video-buf-dvb.o
 obj-$(CONFIG_VIDEO_BTCX)  += btcx-risc.o
 obj-$(CONFIG_VIDEO_TVEEPROM) += tveeprom.o
diff --git a/drivers/media/video/videobuf-vmalloc.c b/drivers/media/video/videobuf-vmalloc.c
new file mode 100644 (file)
index 0000000..993d528
--- /dev/null
@@ -0,0 +1,384 @@
+/*
+ * helper functions for vmalloc video4linux capture buffers
+ *
+ * The functions expect the hardware being able to scatter gatter
+ * (i.e. the buffers are not linear in physical memory, but fragmented
+ * into PAGE_SIZE chunks).  They also assume the driver does not need
+ * to touch the video data.
+ *
+ * (c) 2007 Mauro Carvalho Chehab, <mchehab@infradead.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+
+#include <linux/pci.h>
+#include <linux/vmalloc.h>
+#include <linux/pagemap.h>
+#include <asm/page.h>
+#include <asm/pgtable.h>
+
+#include <media/videobuf-vmalloc.h>
+
+#define MAGIC_DMABUF   0x17760309
+#define MAGIC_VMAL_MEM 0x18221223
+
+#define MAGIC_CHECK(is,should) if (unlikely((is) != (should))) \
+       { printk(KERN_ERR "magic mismatch: %x (expected %x)\n",is,should); BUG(); }
+
+static int debug = 0;
+module_param(debug, int, 0644);
+
+MODULE_DESCRIPTION("helper module to manage video4linux vmalloc buffers");
+MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@infradead.org>");
+MODULE_LICENSE("GPL");
+
+#define dprintk(level, fmt, arg...)    if (debug >= level) \
+       printk(KERN_DEBUG "vbuf-sg: " fmt , ## arg)
+
+
+/***************************************************************************/
+
+static void
+videobuf_vm_open(struct vm_area_struct *vma)
+{
+       struct videobuf_mapping *map = vma->vm_private_data;
+
+       dprintk(2,"vm_open %p [count=%d,vma=%08lx-%08lx]\n",map,
+               map->count,vma->vm_start,vma->vm_end);
+
+       map->count++;
+}
+
+static void
+videobuf_vm_close(struct vm_area_struct *vma)
+{
+       struct videobuf_mapping *map = vma->vm_private_data;
+       struct videobuf_queue *q = map->q;
+       struct videbuf_vmalloc_memory *mem;
+       int i;
+
+       dprintk(2,"vm_close %p [count=%d,vma=%08lx-%08lx]\n",map,
+               map->count,vma->vm_start,vma->vm_end);
+
+       map->count--;
+       if (0 == map->count) {
+               dprintk(1,"munmap %p q=%p\n",map,q);
+               mutex_lock(&q->lock);
+               for (i = 0; i < VIDEO_MAX_FRAME; i++) {
+                       if (NULL == q->bufs[i])
+                               continue;
+                       mem=q->bufs[i]->priv;
+
+                       if (!mem)
+                               continue;
+
+                       MAGIC_CHECK(mem->magic,MAGIC_VMAL_MEM);
+
+                       if (mem->map != map)
+                               continue;
+                       mem->map   = NULL;
+                       q->bufs[i]->baddr = 0;
+                       q->ops->buf_release(q,q->bufs[i]);
+               }
+               mutex_unlock(&q->lock);
+               kfree(map);
+       }
+       return;
+}
+
+static struct vm_operations_struct videobuf_vm_ops =
+{
+       .open     = videobuf_vm_open,
+       .close    = videobuf_vm_close,
+};
+
+/* ---------------------------------------------------------------------
+ * vmalloc handlers for the generic methods
+ */
+
+/* Allocated area consists on 3 parts:
+       struct video_buffer
+       struct <driver>_buffer (cx88_buffer, saa7134_buf, ...)
+       struct videobuf_pci_sg_memory
+ */
+
+static void *__videobuf_alloc(size_t size)
+{
+       struct videbuf_vmalloc_memory *mem;
+       struct videobuf_buffer *vb;
+
+       vb = kzalloc(size+sizeof(*mem),GFP_KERNEL);
+
+       mem = vb->priv = ((char *)vb)+size;
+       mem->magic=MAGIC_VMAL_MEM;
+
+       dprintk(1,"%s: allocated at %p(%ld+%ld) & %p(%ld)\n",
+               __FUNCTION__,vb,(long)sizeof(*vb),(long)size-sizeof(*vb),
+               mem,(long)sizeof(*mem));
+
+       return vb;
+}
+
+static int __videobuf_iolock (struct videobuf_queue* q,
+                             struct videobuf_buffer *vb,
+                             struct v4l2_framebuffer *fbuf)
+{
+       int pages;
+
+       struct videbuf_vmalloc_memory *mem=vb->priv;
+
+
+       BUG_ON(!mem);
+
+       MAGIC_CHECK(mem->magic,MAGIC_VMAL_MEM);
+
+
+       pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT;
+
+       /* Currently, doesn't support V4L2_MEMORY_OVERLAY */
+       if ((vb->memory != V4L2_MEMORY_MMAP) &&
+                               (vb->memory != V4L2_MEMORY_USERPTR) ) {
+               printk(KERN_ERR "Method currently unsupported.\n");
+               return -EINVAL;
+       }
+
+       /* FIXME: should be tested with kernel mmap mem */
+       mem->vmalloc=vmalloc_user (PAGE_ALIGN(vb->size));
+       if (NULL == mem->vmalloc) {
+               dprintk(1,"vmalloc (%d pages) failed\n",pages);
+               return -ENOMEM;
+       }
+
+       dprintk(1,"vmalloc is at addr 0x%08lx, size=%d\n",
+                               (unsigned long)mem->vmalloc,
+                               pages << PAGE_SHIFT);
+
+       /* It seems that some kernel versions need to do remap *after*
+          the mmap() call
+        */
+       if (mem->vma) {
+               int retval=remap_vmalloc_range(mem->vma, mem->vmalloc,0);
+               kfree(mem->vma);
+               mem->vma=NULL;
+               if (retval<0) {
+                       dprintk(1,"mmap app bug: remap_vmalloc_range area %p error %d\n",
+                               mem->vmalloc,retval);
+                       return retval;
+               }
+       }
+
+       return 0;
+}
+
+static int __videobuf_sync(struct videobuf_queue *q,
+                          struct videobuf_buffer *buf)
+{
+       return 0;
+}
+
+static int __videobuf_mmap_free(struct videobuf_queue *q)
+{
+       unsigned int i;
+
+       for (i = 0; i < VIDEO_MAX_FRAME; i++) {
+               if (q->bufs[i]) {
+                       struct videbuf_vmalloc_memory *mem=q->bufs[i]->priv;
+                       if (mem && mem->map)
+                               return -EBUSY;
+               }
+       }
+
+       return 0;
+}
+
+static int __videobuf_mmap_mapper(struct videobuf_queue *q,
+                        struct vm_area_struct *vma)
+{
+       struct videbuf_vmalloc_memory *mem;
+       struct videobuf_mapping *map;
+       unsigned int first;
+       int retval;
+       unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
+
+       if (! (vma->vm_flags & VM_WRITE) || ! (vma->vm_flags & VM_SHARED))
+               return -EINVAL;
+
+       /* look for first buffer to map */
+       for (first = 0; first < VIDEO_MAX_FRAME; first++) {
+               if (NULL == q->bufs[first])
+                       continue;
+
+               if (V4L2_MEMORY_MMAP != q->bufs[first]->memory)
+                       continue;
+               if (q->bufs[first]->boff == offset)
+                       break;
+       }
+       if (VIDEO_MAX_FRAME == first) {
+               dprintk(1,"mmap app bug: offset invalid [offset=0x%lx]\n",
+                       (vma->vm_pgoff << PAGE_SHIFT));
+               return -EINVAL;
+       }
+       mem=q->bufs[first]->priv;
+       BUG_ON (!mem);
+       MAGIC_CHECK(mem->magic,MAGIC_VMAL_MEM);
+
+       /* create mapping + update buffer list */
+       map = mem->map = kmalloc(sizeof(struct videobuf_mapping),GFP_KERNEL);
+       if (NULL == map)
+               return -ENOMEM;
+
+       map->start = vma->vm_start;
+       map->end   = vma->vm_end;
+       map->q     = q;
+
+       q->bufs[first]->baddr = vma->vm_start;
+
+       vma->vm_ops          = &videobuf_vm_ops;
+       vma->vm_flags       |= VM_DONTEXPAND | VM_RESERVED;
+       vma->vm_private_data = map;
+
+       /* Try to remap memory */
+       retval=remap_vmalloc_range(vma, mem->vmalloc,0);
+       if (retval<0) {
+               dprintk(1,"mmap: postponing remap_vmalloc_range\n");
+               mem->vma=kmalloc(sizeof(*vma),GFP_KERNEL);
+               if (!mem->vma) {
+                       kfree(map);
+                       mem->map=NULL;
+                       return -ENOMEM;
+               }
+               memcpy(mem->vma,vma,sizeof(*vma));
+       }
+
+       dprintk(1,"mmap %p: q=%p %08lx-%08lx (%lx) pgoff %08lx buf %d\n",
+               map,q,vma->vm_start,vma->vm_end,
+               (long int) q->bufs[first]->bsize,
+               vma->vm_pgoff,first);
+
+       videobuf_vm_open(vma);
+
+       return (0);
+}
+
+static int __videobuf_is_mmapped (struct videobuf_buffer *buf)
+{
+       struct videbuf_vmalloc_memory *mem=buf->priv;
+       BUG_ON (!mem);
+       MAGIC_CHECK(mem->magic,MAGIC_VMAL_MEM);
+
+       return (mem->map)?1:0;
+}
+
+static int __videobuf_copy_to_user ( struct videobuf_queue *q,
+                               char __user *data, size_t count,
+                               int nonblocking )
+{
+       struct videbuf_vmalloc_memory *mem=q->read_buf->priv;
+       BUG_ON (!mem);
+       MAGIC_CHECK(mem->magic,MAGIC_VMAL_MEM);
+
+       BUG_ON (!mem->vmalloc);
+
+       /* copy to userspace */
+       if (count > q->read_buf->size - q->read_off)
+               count = q->read_buf->size - q->read_off;
+
+       if (copy_to_user(data, mem->vmalloc+q->read_off, count))
+               return -EFAULT;
+
+       return count;
+}
+
+static int __videobuf_copy_stream ( struct videobuf_queue *q,
+                               char __user *data, size_t count, size_t pos,
+                               int vbihack, int nonblocking )
+{
+       unsigned int  *fc;
+       struct videbuf_vmalloc_memory *mem=q->read_buf->priv;
+       BUG_ON (!mem);
+       MAGIC_CHECK(mem->magic,MAGIC_VMAL_MEM);
+
+       if (vbihack) {
+               /* dirty, undocumented hack -- pass the frame counter
+                       * within the last four bytes of each vbi data block.
+                       * We need that one to maintain backward compatibility
+                       * to all vbi decoding software out there ... */
+               fc  = (unsigned int*)mem->vmalloc;
+               fc += (q->read_buf->size>>2) -1;
+               *fc = q->read_buf->field_count >> 1;
+               dprintk(1,"vbihack: %d\n",*fc);
+       }
+
+       /* copy stuff using the common method */
+       count = __videobuf_copy_to_user (q,data,count,nonblocking);
+
+       if ( (count==-EFAULT) && (0 == pos) )
+               return -EFAULT;
+
+       return count;
+}
+
+static struct videobuf_qtype_ops qops = {
+       .magic        = MAGIC_QTYPE_OPS,
+
+       .alloc        = __videobuf_alloc,
+       .iolock       = __videobuf_iolock,
+       .sync         = __videobuf_sync,
+       .mmap_free    = __videobuf_mmap_free,
+       .mmap_mapper  = __videobuf_mmap_mapper,
+       .is_mmapped   = __videobuf_is_mmapped,
+       .copy_to_user = __videobuf_copy_to_user,
+       .copy_stream  = __videobuf_copy_stream,
+};
+
+void videobuf_queue_vmalloc_init(struct videobuf_queue* q,
+                        struct videobuf_queue_ops *ops,
+                        void *dev,
+                        spinlock_t *irqlock,
+                        enum v4l2_buf_type type,
+                        enum v4l2_field field,
+                        unsigned int msize,
+                        void *priv)
+{
+       videobuf_queue_init(q, ops, dev, irqlock, type, field, msize, priv);
+       q->int_ops=&qops;
+}
+
+EXPORT_SYMBOL_GPL(videobuf_queue_vmalloc_init);
+
+void *videobuf_to_vmalloc (struct videobuf_buffer *buf)
+{
+       struct videbuf_vmalloc_memory *mem=buf->priv;
+       BUG_ON (!mem);
+       MAGIC_CHECK(mem->magic,MAGIC_VMAL_MEM);
+
+       return mem->vmalloc;
+}
+EXPORT_SYMBOL_GPL(videobuf_to_vmalloc);
+
+void videobuf_vmalloc_free (struct videobuf_buffer *buf)
+{
+       struct videbuf_vmalloc_memory *mem=buf->priv;
+       BUG_ON (!mem);
+
+       MAGIC_CHECK(mem->magic,MAGIC_VMAL_MEM);
+
+       vfree(mem->vmalloc);
+
+       return;
+}
+EXPORT_SYMBOL_GPL(videobuf_vmalloc_free);
+
+/*
+ * Local variables:
+ * c-basic-offset: 8
+ * End:
+ */
diff --git a/include/media/videobuf-vmalloc.h b/include/media/videobuf-vmalloc.h
new file mode 100644 (file)
index 0000000..5fff68d
--- /dev/null
@@ -0,0 +1,44 @@
+/*
+ * helper functions for vmalloc capture buffers
+ *
+ * The functions expect the hardware being able to scatter gatter
+ * (i.e. the buffers are not linear in physical memory, but fragmented
+ * into PAGE_SIZE chunks).  They also assume the driver does not need
+ * to touch the video data.
+ *
+ * (c) 2007 Mauro Carvalho Chehab, <mchehab@infradead.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2
+ */
+
+#include <media/videobuf-core.h>
+
+/* --------------------------------------------------------------------- */
+
+struct videbuf_vmalloc_memory
+{
+       u32                 magic;
+
+       /* for mmap'ed buffers */
+       struct videobuf_mapping *map;
+
+       void                *vmalloc;
+
+       /* remap_vmalloc_range seems to need to run after mmap() on some cases */
+       struct vm_area_struct *vma;
+};
+
+void videobuf_queue_vmalloc_init(struct videobuf_queue* q,
+                        struct videobuf_queue_ops *ops,
+                        void *dev,
+                        spinlock_t *irqlock,
+                        enum v4l2_buf_type type,
+                        enum v4l2_field field,
+                        unsigned int msize,
+                        void *priv);
+
+void *videobuf_to_vmalloc (struct videobuf_buffer *buf);
+
+void videobuf_vmalloc_free (struct videobuf_buffer *buf);