From 87b9ad070cf76c0f1e8cf836f7eb86e9ac94e34a Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Thu, 2 Aug 2007 23:31:33 -0300 Subject: V4L/DVB (6254): Add videobuf-vmalloc 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 --- drivers/media/Kconfig | 4 + drivers/media/video/Kconfig | 2 +- drivers/media/video/Makefile | 1 + drivers/media/video/videobuf-vmalloc.c | 384 +++++++++++++++++++++++++++++++++ 4 files changed, 390 insertions(+), 1 deletion(-) create mode 100644 drivers/media/video/videobuf-vmalloc.c (limited to 'drivers/media') diff --git a/drivers/media/Kconfig b/drivers/media/Kconfig index 28ee65c..fc3ea4c 100644 --- a/drivers/media/Kconfig +++ b/drivers/media/Kconfig @@ -134,6 +134,10 @@ config VIDEOBUF_DMA_SG select VIDEOBUF_GEN tristate +config VIDEOBUF_VMALLOC + select VIDEOBUF_GEN + tristate + config VIDEO_BUF_DVB tristate diff --git a/drivers/media/video/Kconfig b/drivers/media/video/Kconfig index c4f4244..2e571eb 100644 --- a/drivers/media/video/Kconfig +++ b/drivers/media/video/Kconfig @@ -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 diff --git a/drivers/media/video/Makefile b/drivers/media/video/Makefile index cb30024..c8140ae 100644 --- a/drivers/media/video/Makefile +++ b/drivers/media/video/Makefile @@ -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 index 0000000..993d528 --- /dev/null +++ b/drivers/media/video/videobuf-vmalloc.c @@ -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, + * + * 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 +#include +#include +#include +#include + +#include +#include +#include +#include +#include + +#include + +#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 "); +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 _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: + */ -- cgit v1.1