diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-10-07 17:49:05 +0900 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-10-07 17:49:05 +0900 |
commit | 0b8e74c6f44094189dbe78baf4101acc7570c6af (patch) | |
tree | 6440561d09fb71ba5928664604ec92f29940be6b /drivers/media/platform/omap3isp/ispqueue.c | |
parent | 7f60ba388f5b9dd8b0da463b394412dace3ab814 (diff) | |
parent | bd0d10498826ed150da5e4c45baf8b9c7088fb71 (diff) | |
download | lwn-0b8e74c6f44094189dbe78baf4101acc7570c6af.tar.gz lwn-0b8e74c6f44094189dbe78baf4101acc7570c6af.zip |
Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
Pull media updates from Mauro Carvalho Chehab:
"The first part of the media updates for Kernel 3.7.
This series contain:
- A major tree renaming patch series: now, drivers are organized
internally by their used bus, instead of by V4L2 and/or DVB API,
providing a cleaner driver location for hybrid drivers that
implement both APIs, and allowing to cleanup the Kconfig items and
make them more intuitive for the end user;
- Media Kernel developers are typically very lazy with their duties
of keeping the MAINTAINERS entries for their drivers updated. As
now the tree is more organized, we're doing an effort to add/update
those entries for the drivers that aren't currently orphan;
- Several DVB USB drivers got moved to a new DVB USB v2 core; the new
core fixes several bugs (as the existing one that got bitroted).
Now, suspend/resume finally started to work fine (at least with
some devices - we should expect more work with regards to it);
- added multistream support for DVB-T2, and unified the API for
DVB-S2 and ISDB-S. Backward binary support is preserved;
- as usual, a few new drivers, some V4L2 core improvements and lots
of drivers improvements and fixes.
There are some points to notice on this series:
1) you should expect a trivial merge conflict on your tree, with the
removal of Documentation/feature-removal-schedule.txt: this series
would be adding two additional entries there. I opted to not
rebase it due to this recent change;
2) With regards to the PCTV 520e udev-related breakage, I opted to
fix it in a way that the patches can be backported to 3.5 even
without your firmware fix patch. This way, Greg doesn't need to
rush backporting your patch (as there are still the firmware cache
and firmware path customization issues to be addressed there).
I'll send later a patch (likely after the end of the merge window)
reverting the rest of the DRX-K async firmware request, fully
restoring its original behaviour to allow media drivers to
initialize everything serialized as before for 3.7 and upper.
3) I'm planning to work on this weekend to test the DMABUF patches
for V4L2. The patches are on my queue for several Kernel cycles,
but, up to now, there is/was no way to test the series locally.
I have some concerns about this particular changeset with regards
to security issues, and with regards to the replacement of the old
VIDIOC_OVERLAY ioctl's that is broken on modern systems, due to
GPU drivers change. The Overlay API allows direct PCI2PCI
transfers from a media capture card into the GPU framebuffer, but
its API is crappy. Also, the only existing X11 driver that
implements it requires a XV extension that is not available
anymore on modern drivers. The DMABUF can do the same thing, but
with it is promising to be a properly-designed API. If I can
successfully test this series and be happy with it, I should be
asking you to pull them next week."
* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (717 commits)
em28xx: regression fix: use DRX-K sync firmware requests on em28xx
drxk: allow loading firmware synchrousnously
em28xx: Make all em28xx extensions to be initialized asynchronously
[media] tda18271: properly report read errors in tda18271_get_id
[media] tda18271: delay IR & RF calibration until init() if delay_cal is set
[media] MAINTAINERS: add Michael Krufky as tda827x maintainer
[media] MAINTAINERS: add Michael Krufky as tda8290 maintainer
[media] MAINTAINERS: add Michael Krufky as cxusb maintainer
[media] MAINTAINERS: add Michael Krufky as lg2160 maintainer
[media] MAINTAINERS: add Michael Krufky as lgdt3305 maintainer
[media] MAINTAINERS: add Michael Krufky as mxl111sf maintainer
[media] MAINTAINERS: add Michael Krufky as mxl5007t maintainer
[media] MAINTAINERS: add Michael Krufky as tda18271 maintainer
[media] s5p-tv: Report only multi-plane capabilities in vidioc_querycap
[media] s5p-mfc: Fix misplaced return statement in s5p_mfc_suspend()
[media] exynos-gsc: Add missing static storage class specifiers
[media] exynos-gsc: Remove <linux/version.h> header file inclusion
[media] s5p-fimc: Fix incorrect condition in fimc_lite_reqbufs()
[media] s5p-tv: Fix potential NULL pointer dereference error
[media] s5k6aa: Fix possible NULL pointer dereference
...
Diffstat (limited to 'drivers/media/platform/omap3isp/ispqueue.c')
-rw-r--r-- | drivers/media/platform/omap3isp/ispqueue.c | 1158 |
1 files changed, 1158 insertions, 0 deletions
diff --git a/drivers/media/platform/omap3isp/ispqueue.c b/drivers/media/platform/omap3isp/ispqueue.c new file mode 100644 index 000000000000..15bf3eab2224 --- /dev/null +++ b/drivers/media/platform/omap3isp/ispqueue.c @@ -0,0 +1,1158 @@ +/* + * ispqueue.c + * + * TI OMAP3 ISP - Video buffers queue handling + * + * Copyright (C) 2010 Nokia Corporation + * + * Contacts: Laurent Pinchart <laurent.pinchart@ideasonboard.com> + * Sakari Ailus <sakari.ailus@iki.fi> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA + * 02110-1301 USA + */ + +#include <asm/cacheflush.h> +#include <linux/dma-mapping.h> +#include <linux/mm.h> +#include <linux/pagemap.h> +#include <linux/poll.h> +#include <linux/scatterlist.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/vmalloc.h> + +#include "ispqueue.h" + +/* ----------------------------------------------------------------------------- + * Video buffers management + */ + +/* + * isp_video_buffer_cache_sync - Keep the buffers coherent between CPU and ISP + * + * The typical operation required here is Cache Invalidation across + * the (user space) buffer address range. And this _must_ be done + * at QBUF stage (and *only* at QBUF). + * + * We try to use optimal cache invalidation function: + * - dmac_map_area: + * - used when the number of pages are _low_. + * - it becomes quite slow as the number of pages increase. + * - for 648x492 viewfinder (150 pages) it takes 1.3 ms. + * - for 5 Mpix buffer (2491 pages) it takes between 25-50 ms. + * + * - flush_cache_all: + * - used when the number of pages are _high_. + * - time taken in the range of 500-900 us. + * - has a higher penalty but, as whole dcache + icache is invalidated + */ +/* + * FIXME: dmac_inv_range crashes randomly on the user space buffer + * address. Fall back to flush_cache_all for now. + */ +#define ISP_CACHE_FLUSH_PAGES_MAX 0 + +static void isp_video_buffer_cache_sync(struct isp_video_buffer *buf) +{ + if (buf->skip_cache) + return; + + if (buf->vbuf.m.userptr == 0 || buf->npages == 0 || + buf->npages > ISP_CACHE_FLUSH_PAGES_MAX) + flush_cache_all(); + else { + dmac_map_area((void *)buf->vbuf.m.userptr, buf->vbuf.length, + DMA_FROM_DEVICE); + outer_inv_range(buf->vbuf.m.userptr, + buf->vbuf.m.userptr + buf->vbuf.length); + } +} + +/* + * isp_video_buffer_lock_vma - Prevent VMAs from being unmapped + * + * Lock the VMAs underlying the given buffer into memory. This avoids the + * userspace buffer mapping from being swapped out, making VIPT cache handling + * easier. + * + * Note that the pages will not be freed as the buffers have been locked to + * memory using by a call to get_user_pages(), but the userspace mapping could + * still disappear if the VMAs are not locked. This is caused by the memory + * management code trying to be as lock-less as possible, which results in the + * userspace mapping manager not finding out that the pages are locked under + * some conditions. + */ +static int isp_video_buffer_lock_vma(struct isp_video_buffer *buf, int lock) +{ + struct vm_area_struct *vma; + unsigned long start; + unsigned long end; + int ret = 0; + + if (buf->vbuf.memory == V4L2_MEMORY_MMAP) + return 0; + + /* We can be called from workqueue context if the current task dies to + * unlock the VMAs. In that case there's no current memory management + * context so unlocking can't be performed, but the VMAs have been or + * are getting destroyed anyway so it doesn't really matter. + */ + if (!current || !current->mm) + return lock ? -EINVAL : 0; + + start = buf->vbuf.m.userptr; + end = buf->vbuf.m.userptr + buf->vbuf.length - 1; + + down_write(¤t->mm->mmap_sem); + spin_lock(¤t->mm->page_table_lock); + + do { + vma = find_vma(current->mm, start); + if (vma == NULL) { + ret = -EFAULT; + goto out; + } + + if (lock) + vma->vm_flags |= VM_LOCKED; + else + vma->vm_flags &= ~VM_LOCKED; + + start = vma->vm_end + 1; + } while (vma->vm_end < end); + + if (lock) + buf->vm_flags |= VM_LOCKED; + else + buf->vm_flags &= ~VM_LOCKED; + +out: + spin_unlock(¤t->mm->page_table_lock); + up_write(¤t->mm->mmap_sem); + return ret; +} + +/* + * isp_video_buffer_sglist_kernel - Build a scatter list for a vmalloc'ed buffer + * + * Iterate over the vmalloc'ed area and create a scatter list entry for every + * page. + */ +static int isp_video_buffer_sglist_kernel(struct isp_video_buffer *buf) +{ + struct scatterlist *sglist; + unsigned int npages; + unsigned int i; + void *addr; + + addr = buf->vaddr; + npages = PAGE_ALIGN(buf->vbuf.length) >> PAGE_SHIFT; + + sglist = vmalloc(npages * sizeof(*sglist)); + if (sglist == NULL) + return -ENOMEM; + + sg_init_table(sglist, npages); + + for (i = 0; i < npages; ++i, addr += PAGE_SIZE) { + struct page *page = vmalloc_to_page(addr); + + if (page == NULL || PageHighMem(page)) { + vfree(sglist); + return -EINVAL; + } + + sg_set_page(&sglist[i], page, PAGE_SIZE, 0); + } + + buf->sglen = npages; + buf->sglist = sglist; + + return 0; +} + +/* + * isp_video_buffer_sglist_user - Build a scatter list for a userspace buffer + * + * Walk the buffer pages list and create a 1:1 mapping to a scatter list. + */ +static int isp_video_buffer_sglist_user(struct isp_video_buffer *buf) +{ + struct scatterlist *sglist; + unsigned int offset = buf->offset; + unsigned int i; + + sglist = vmalloc(buf->npages * sizeof(*sglist)); + if (sglist == NULL) + return -ENOMEM; + + sg_init_table(sglist, buf->npages); + + for (i = 0; i < buf->npages; ++i) { + if (PageHighMem(buf->pages[i])) { + vfree(sglist); + return -EINVAL; + } + + sg_set_page(&sglist[i], buf->pages[i], PAGE_SIZE - offset, + offset); + offset = 0; + } + + buf->sglen = buf->npages; + buf->sglist = sglist; + + return 0; +} + +/* + * isp_video_buffer_sglist_pfnmap - Build a scatter list for a VM_PFNMAP buffer + * + * Create a scatter list of physically contiguous pages starting at the buffer + * memory physical address. + */ +static int isp_video_buffer_sglist_pfnmap(struct isp_video_buffer *buf) +{ + struct scatterlist *sglist; + unsigned int offset = buf->offset; + unsigned long pfn = buf->paddr >> PAGE_SHIFT; + unsigned int i; + + sglist = vmalloc(buf->npages * sizeof(*sglist)); + if (sglist == NULL) + return -ENOMEM; + + sg_init_table(sglist, buf->npages); + + for (i = 0; i < buf->npages; ++i, ++pfn) { + sg_set_page(&sglist[i], pfn_to_page(pfn), PAGE_SIZE - offset, + offset); + /* PFNMAP buffers will not get DMA-mapped, set the DMA address + * manually. + */ + sg_dma_address(&sglist[i]) = (pfn << PAGE_SHIFT) + offset; + offset = 0; + } + + buf->sglen = buf->npages; + buf->sglist = sglist; + + return 0; +} + +/* + * isp_video_buffer_cleanup - Release pages for a userspace VMA. + * + * Release pages locked by a call isp_video_buffer_prepare_user and free the + * pages table. + */ +static void isp_video_buffer_cleanup(struct isp_video_buffer *buf) +{ + enum dma_data_direction direction; + unsigned int i; + + if (buf->queue->ops->buffer_cleanup) + buf->queue->ops->buffer_cleanup(buf); + + if (!(buf->vm_flags & VM_PFNMAP)) { + direction = buf->vbuf.type == V4L2_BUF_TYPE_VIDEO_CAPTURE + ? DMA_FROM_DEVICE : DMA_TO_DEVICE; + dma_unmap_sg(buf->queue->dev, buf->sglist, buf->sglen, + direction); + } + + vfree(buf->sglist); + buf->sglist = NULL; + buf->sglen = 0; + + if (buf->pages != NULL) { + isp_video_buffer_lock_vma(buf, 0); + + for (i = 0; i < buf->npages; ++i) + page_cache_release(buf->pages[i]); + + vfree(buf->pages); + buf->pages = NULL; + } + + buf->npages = 0; + buf->skip_cache = false; +} + +/* + * isp_video_buffer_prepare_user - Pin userspace VMA pages to memory. + * + * This function creates a list of pages for a userspace VMA. The number of + * pages is first computed based on the buffer size, and pages are then + * retrieved by a call to get_user_pages. + * + * Pages are pinned to memory by get_user_pages, making them available for DMA + * transfers. However, due to memory management optimization, it seems the + * get_user_pages doesn't guarantee that the pinned pages will not be written + * to swap and removed from the userspace mapping(s). When this happens, a page + * fault can be generated when accessing those unmapped pages. + * + * If the fault is triggered by a page table walk caused by VIPT cache + * management operations, the page fault handler might oops if the MM semaphore + * is held, as it can't handle kernel page faults in that case. To fix that, a + * fixup entry needs to be added to the cache management code, or the userspace + * VMA must be locked to avoid removing pages from the userspace mapping in the + * first place. + * + * If the number of pages retrieved is smaller than the number required by the + * buffer size, the function returns -EFAULT. + */ +static int isp_video_buffer_prepare_user(struct isp_video_buffer *buf) +{ + unsigned long data; + unsigned int first; + unsigned int last; + int ret; + + data = buf->vbuf.m.userptr; + first = (data & PAGE_MASK) >> PAGE_SHIFT; + last = ((data + buf->vbuf.length - 1) & PAGE_MASK) >> PAGE_SHIFT; + + buf->offset = data & ~PAGE_MASK; + buf->npages = last - first + 1; + buf->pages = vmalloc(buf->npages * sizeof(buf->pages[0])); + if (buf->pages == NULL) + return -ENOMEM; + + down_read(¤t->mm->mmap_sem); + ret = get_user_pages(current, current->mm, data & PAGE_MASK, + buf->npages, + buf->vbuf.type == V4L2_BUF_TYPE_VIDEO_CAPTURE, 0, + buf->pages, NULL); + up_read(¤t->mm->mmap_sem); + + if (ret != buf->npages) { + buf->npages = ret < 0 ? 0 : ret; + isp_video_buffer_cleanup(buf); + return -EFAULT; + } + + ret = isp_video_buffer_lock_vma(buf, 1); + if (ret < 0) + isp_video_buffer_cleanup(buf); + + return ret; +} + +/* + * isp_video_buffer_prepare_pfnmap - Validate a VM_PFNMAP userspace buffer + * + * Userspace VM_PFNMAP buffers are supported only if they are contiguous in + * memory and if they span a single VMA. + * + * Return 0 if the buffer is valid, or -EFAULT otherwise. + */ +static int isp_video_buffer_prepare_pfnmap(struct isp_video_buffer *buf) +{ + struct vm_area_struct *vma; + unsigned long prev_pfn; + unsigned long this_pfn; + unsigned long start; + unsigned long end; + dma_addr_t pa; + int ret = -EFAULT; + + start = buf->vbuf.m.userptr; + end = buf->vbuf.m.userptr + buf->vbuf.length - 1; + + buf->offset = start & ~PAGE_MASK; + buf->npages = (end >> PAGE_SHIFT) - (start >> PAGE_SHIFT) + 1; + buf->pages = NULL; + + down_read(¤t->mm->mmap_sem); + vma = find_vma(current->mm, start); + if (vma == NULL || vma->vm_end < end) + goto done; + + for (prev_pfn = 0; start <= end; start += PAGE_SIZE) { + ret = follow_pfn(vma, start, &this_pfn); + if (ret) + goto done; + + if (prev_pfn == 0) + pa = this_pfn << PAGE_SHIFT; + else if (this_pfn != prev_pfn + 1) { + ret = -EFAULT; + goto done; + } + + prev_pfn = this_pfn; + } + + buf->paddr = pa + buf->offset; + ret = 0; + +done: + up_read(¤t->mm->mmap_sem); + return ret; +} + +/* + * isp_video_buffer_prepare_vm_flags - Get VMA flags for a userspace address + * + * This function locates the VMAs for the buffer's userspace address and checks + * that their flags match. The only flag that we need to care for at the moment + * is VM_PFNMAP. + * + * The buffer vm_flags field is set to the first VMA flags. + * + * Return -EFAULT if no VMA can be found for part of the buffer, or if the VMAs + * have incompatible flags. + */ +static int isp_video_buffer_prepare_vm_flags(struct isp_video_buffer *buf) +{ + struct vm_area_struct *vma; + pgprot_t vm_page_prot; + unsigned long start; + unsigned long end; + int ret = -EFAULT; + + start = buf->vbuf.m.userptr; + end = buf->vbuf.m.userptr + buf->vbuf.length - 1; + + down_read(¤t->mm->mmap_sem); + + do { + vma = find_vma(current->mm, start); + if (vma == NULL) + goto done; + + if (start == buf->vbuf.m.userptr) { + buf->vm_flags = vma->vm_flags; + vm_page_prot = vma->vm_page_prot; + } + + if ((buf->vm_flags ^ vma->vm_flags) & VM_PFNMAP) + goto done; + + if (vm_page_prot != vma->vm_page_prot) + goto done; + + start = vma->vm_end + 1; + } while (vma->vm_end < end); + + /* Skip cache management to enhance performances for non-cached or + * write-combining buffers. + */ + if (vm_page_prot == pgprot_noncached(vm_page_prot) || + vm_page_prot == pgprot_writecombine(vm_page_prot)) + buf->skip_cache = true; + + ret = 0; + +done: + up_read(¤t->mm->mmap_sem); + return ret; +} + +/* + * isp_video_buffer_prepare - Make a buffer ready for operation + * + * Preparing a buffer involves: + * + * - validating VMAs (userspace buffers only) + * - locking pages and VMAs into memory (userspace buffers only) + * - building page and scatter-gather lists + * - mapping buffers for DMA operation + * - performing driver-specific preparation + * + * The function must be called in userspace context with a valid mm context + * (this excludes cleanup paths such as sys_close when the userspace process + * segfaults). + */ +static int isp_video_buffer_prepare(struct isp_video_buffer *buf) +{ + enum dma_data_direction direction; + int ret; + + switch (buf->vbuf.memory) { + case V4L2_MEMORY_MMAP: + ret = isp_video_buffer_sglist_kernel(buf); + break; + + case V4L2_MEMORY_USERPTR: + ret = isp_video_buffer_prepare_vm_flags(buf); + if (ret < 0) + return ret; + + if (buf->vm_flags & VM_PFNMAP) { + ret = isp_video_buffer_prepare_pfnmap(buf); + if (ret < 0) + return ret; + + ret = isp_video_buffer_sglist_pfnmap(buf); + } else { + ret = isp_video_buffer_prepare_user(buf); + if (ret < 0) + return ret; + + ret = isp_video_buffer_sglist_user(buf); + } + break; + + default: + return -EINVAL; + } + + if (ret < 0) + goto done; + + if (!(buf->vm_flags & VM_PFNMAP)) { + direction = buf->vbuf.type == V4L2_BUF_TYPE_VIDEO_CAPTURE + ? DMA_FROM_DEVICE : DMA_TO_DEVICE; + ret = dma_map_sg(buf->queue->dev, buf->sglist, buf->sglen, + direction); + if (ret != buf->sglen) { + ret = -EFAULT; + goto done; + } + } + + if (buf->queue->ops->buffer_prepare) + ret = buf->queue->ops->buffer_prepare(buf); + +done: + if (ret < 0) { + isp_video_buffer_cleanup(buf); + return ret; + } + + return ret; +} + +/* + * isp_video_queue_query - Query the status of a given buffer + * + * Locking: must be called with the queue lock held. + */ +static void isp_video_buffer_query(struct isp_video_buffer *buf, + struct v4l2_buffer *vbuf) +{ + memcpy(vbuf, &buf->vbuf, sizeof(*vbuf)); + + if (buf->vma_use_count) + vbuf->flags |= V4L2_BUF_FLAG_MAPPED; + + switch (buf->state) { + case ISP_BUF_STATE_ERROR: + vbuf->flags |= V4L2_BUF_FLAG_ERROR; + case ISP_BUF_STATE_DONE: + vbuf->flags |= V4L2_BUF_FLAG_DONE; + case ISP_BUF_STATE_QUEUED: + case ISP_BUF_STATE_ACTIVE: + vbuf->flags |= V4L2_BUF_FLAG_QUEUED; + break; + case ISP_BUF_STATE_IDLE: + default: + break; + } +} + +/* + * isp_video_buffer_wait - Wait for a buffer to be ready + * + * In non-blocking mode, return immediately with 0 if the buffer is ready or + * -EAGAIN if the buffer is in the QUEUED or ACTIVE state. + * + * In blocking mode, wait (interruptibly but with no timeout) on the buffer wait + * queue using the same condition. + */ +static int isp_video_buffer_wait(struct isp_video_buffer *buf, int nonblocking) +{ + if (nonblocking) { + return (buf->state != ISP_BUF_STATE_QUEUED && + buf->state != ISP_BUF_STATE_ACTIVE) + ? 0 : -EAGAIN; + } + + return wait_event_interruptible(buf->wait, + buf->state != ISP_BUF_STATE_QUEUED && + buf->state != ISP_BUF_STATE_ACTIVE); +} + +/* ----------------------------------------------------------------------------- + * Queue management + */ + +/* + * isp_video_queue_free - Free video buffers memory + * + * Buffers can only be freed if the queue isn't streaming and if no buffer is + * mapped to userspace. Return -EBUSY if those conditions aren't statisfied. + * + * This function must be called with the queue lock held. + */ +static int isp_video_queue_free(struct isp_video_queue *queue) +{ + unsigned int i; + + if (queue->streaming) + return -EBUSY; + + for (i = 0; i < queue->count; ++i) { + if (queue->buffers[i]->vma_use_count != 0) + return -EBUSY; + } + + for (i = 0; i < queue->count; ++i) { + struct isp_video_buffer *buf = queue->buffers[i]; + + isp_video_buffer_cleanup(buf); + + vfree(buf->vaddr); + buf->vaddr = NULL; + + kfree(buf); + queue->buffers[i] = NULL; + } + + INIT_LIST_HEAD(&queue->queue); + queue->count = 0; + return 0; +} + +/* + * isp_video_queue_alloc - Allocate video buffers memory + * + * This function must be called with the queue lock held. + */ +static int isp_video_queue_alloc(struct isp_video_queue *queue, + unsigned int nbuffers, + unsigned int size, enum v4l2_memory memory) +{ + struct isp_video_buffer *buf; + unsigned int i; + void *mem; + int ret; + + /* Start by freeing the buffers. */ + ret = isp_video_queue_free(queue); + if (ret < 0) + return ret; + + /* Bail out if no buffers should be allocated. */ + if (nbuffers == 0) + return 0; + + /* Initialize the allocated buffers. */ + for (i = 0; i < nbuffers; ++i) { + buf = kzalloc(queue->bufsize, GFP_KERNEL); + if (buf == NULL) + break; + + if (memory == V4L2_MEMORY_MMAP) { + /* Allocate video buffers memory for mmap mode. Align + * the size to the page size. + */ + mem = vmalloc_32_user(PAGE_ALIGN(size)); + if (mem == NULL) { + kfree(buf); + break; + } + + buf->vbuf.m.offset = i * PAGE_ALIGN(size); + buf->vaddr = mem; + } + + buf->vbuf.index = i; + buf->vbuf.length = size; + buf->vbuf.type = queue->type; + buf->vbuf.field = V4L2_FIELD_NONE; + buf->vbuf.memory = memory; + + buf->queue = queue; + init_waitqueue_head(&buf->wait); + + queue->buffers[i] = buf; + } + + if (i == 0) + return -ENOMEM; + + queue->count = i; + return nbuffers; +} + +/** + * omap3isp_video_queue_cleanup - Clean up the video buffers queue + * @queue: Video buffers queue + * + * Free all allocated resources and clean up the video buffers queue. The queue + * must not be busy (no ongoing video stream) and buffers must have been + * unmapped. + * + * Return 0 on success or -EBUSY if the queue is busy or buffers haven't been + * unmapped. + */ +int omap3isp_video_queue_cleanup(struct isp_video_queue *queue) +{ + return isp_video_queue_free(queue); +} + +/** + * omap3isp_video_queue_init - Initialize the video buffers queue + * @queue: Video buffers queue + * @type: V4L2 buffer type (capture or output) + * @ops: Driver-specific queue operations + * @dev: Device used for DMA operations + * @bufsize: Size of the driver-specific buffer structure + * + * Initialize the video buffers queue with the supplied parameters. + * + * The queue type must be one of V4L2_BUF_TYPE_VIDEO_CAPTURE or + * V4L2_BUF_TYPE_VIDEO_OUTPUT. Other buffer types are not supported yet. + * + * Buffer objects will be allocated using the given buffer size to allow room + * for driver-specific fields. Driver-specific buffer structures must start + * with a struct isp_video_buffer field. Drivers with no driver-specific buffer + * structure must pass the size of the isp_video_buffer structure in the bufsize + * parameter. + * + * Return 0 on success. + */ +int omap3isp_video_queue_init(struct isp_video_queue *queue, + enum v4l2_buf_type type, + const struct isp_video_queue_operations *ops, + struct device *dev, unsigned int bufsize) +{ + INIT_LIST_HEAD(&queue->queue); + mutex_init(&queue->lock); + spin_lock_init(&queue->irqlock); + + queue->type = type; + queue->ops = ops; + queue->dev = dev; + queue->bufsize = bufsize; + + return 0; +} + +/* ----------------------------------------------------------------------------- + * V4L2 operations + */ + +/** + * omap3isp_video_queue_reqbufs - Allocate video buffers memory + * + * This function is intended to be used as a VIDIOC_REQBUFS ioctl handler. It + * allocated video buffer objects and, for MMAP buffers, buffer memory. + * + * If the number of buffers is 0, all buffers are freed and the function returns + * without performing any allocation. + * + * If the number of buffers is not 0, currently allocated buffers (if any) are + * freed and the requested number of buffers are allocated. Depending on + * driver-specific requirements and on memory availability, a number of buffer + * smaller or bigger than requested can be allocated. This isn't considered as + * an error. + * + * Return 0 on success or one of the following error codes: + * + * -EINVAL if the buffer type or index are invalid + * -EBUSY if the queue is busy (streaming or buffers mapped) + * -ENOMEM if the buffers can't be allocated due to an out-of-memory condition + */ +int omap3isp_video_queue_reqbufs(struct isp_video_queue *queue, + struct v4l2_requestbuffers *rb) +{ + unsigned int nbuffers = rb->count; + unsigned int size; + int ret; + + if (rb->type != queue->type) + return -EINVAL; + + queue->ops->queue_prepare(queue, &nbuffers, &size); + if (size == 0) + return -EINVAL; + + nbuffers = min_t(unsigned int, nbuffers, ISP_VIDEO_MAX_BUFFERS); + + mutex_lock(&queue->lock); + + ret = isp_video_queue_alloc(queue, nbuffers, size, rb->memory); + if (ret < 0) + goto done; + + rb->count = ret; + ret = 0; + +done: + mutex_unlock(&queue->lock); + return ret; +} + +/** + * omap3isp_video_queue_querybuf - Query the status of a buffer in a queue + * + * This function is intended to be used as a VIDIOC_QUERYBUF ioctl handler. It + * returns the status of a given video buffer. + * + * Return 0 on success or -EINVAL if the buffer type or index are invalid. + */ +int omap3isp_video_queue_querybuf(struct isp_video_queue *queue, + struct v4l2_buffer *vbuf) +{ + struct isp_video_buffer *buf; + int ret = 0; + + if (vbuf->type != queue->type) + return -EINVAL; + + mutex_lock(&queue->lock); + + if (vbuf->index >= queue->count) { + ret = -EINVAL; + goto done; + } + + buf = queue->buffers[vbuf->index]; + isp_video_buffer_query(buf, vbuf); + +done: + mutex_unlock(&queue->lock); + return ret; +} + +/** + * omap3isp_video_queue_qbuf - Queue a buffer + * + * This function is intended to be used as a VIDIOC_QBUF ioctl handler. + * + * The v4l2_buffer structure passed from userspace is first sanity tested. If + * sane, the buffer is then processed and added to the main queue and, if the + * queue is streaming, to the IRQ queue. + * + * Before being enqueued, USERPTR buffers are checked for address changes. If + * the buffer has a different userspace address, the old memory area is unlocked + * and the new memory area is locked. + */ +int omap3isp_video_queue_qbuf(struct isp_video_queue *queue, + struct v4l2_buffer *vbuf) +{ + struct isp_video_buffer *buf; + unsigned long flags; + int ret = -EINVAL; + + if (vbuf->type != queue->type) + goto done; + + mutex_lock(&queue->lock); + + if (vbuf->index >= queue->count) + goto done; + + buf = queue->buffers[vbuf->index]; + + if (vbuf->memory != buf->vbuf.memory) + goto done; + + if (buf->state != ISP_BUF_STATE_IDLE) + goto done; + + if (vbuf->memory == V4L2_MEMORY_USERPTR && + vbuf->length < buf->vbuf.length) + goto done; + + if (vbuf->memory == V4L2_MEMORY_USERPTR && + vbuf->m.userptr != buf->vbuf.m.userptr) { + isp_video_buffer_cleanup(buf); + buf->vbuf.m.userptr = vbuf->m.userptr; + buf->prepared = 0; + } + + if (!buf->prepared) { + ret = isp_video_buffer_prepare(buf); + if (ret < 0) + goto done; + buf->prepared = 1; + } + + isp_video_buffer_cache_sync(buf); + + buf->state = ISP_BUF_STATE_QUEUED; + list_add_tail(&buf->stream, &queue->queue); + + if (queue->streaming) { + spin_lock_irqsave(&queue->irqlock, flags); + queue->ops->buffer_queue(buf); + spin_unlock_irqrestore(&queue->irqlock, flags); + } + + ret = 0; + +done: + mutex_unlock(&queue->lock); + return ret; +} + +/** + * omap3isp_video_queue_dqbuf - Dequeue a buffer + * + * This function is intended to be used as a VIDIOC_DQBUF ioctl handler. + * + * Wait until a buffer is ready to be dequeued, remove it from the queue and + * copy its information to the v4l2_buffer structure. + * + * If the nonblocking argument is not zero and no buffer is ready, return + * -EAGAIN immediately instead of waiting. + * + * If no buffer has been enqueued, or if the requested buffer type doesn't match + * the queue type, return -EINVAL. + */ +int omap3isp_video_queue_dqbuf(struct isp_video_queue *queue, + struct v4l2_buffer *vbuf, int nonblocking) +{ + struct isp_video_buffer *buf; + int ret; + + if (vbuf->type != queue->type) + return -EINVAL; + + mutex_lock(&queue->lock); + + if (list_empty(&queue->queue)) { + ret = -EINVAL; + goto done; + } + + buf = list_first_entry(&queue->queue, struct isp_video_buffer, stream); + ret = isp_video_buffer_wait(buf, nonblocking); + if (ret < 0) + goto done; + + list_del(&buf->stream); + + isp_video_buffer_query(buf, vbuf); + buf->state = ISP_BUF_STATE_IDLE; + vbuf->flags &= ~V4L2_BUF_FLAG_QUEUED; + +done: + mutex_unlock(&queue->lock); + return ret; +} + +/** + * omap3isp_video_queue_streamon - Start streaming + * + * This function is intended to be used as a VIDIOC_STREAMON ioctl handler. It + * starts streaming on the queue and calls the buffer_queue operation for all + * queued buffers. + * + * Return 0 on success. + */ +int omap3isp_video_queue_streamon(struct isp_video_queue *queue) +{ + struct isp_video_buffer *buf; + unsigned long flags; + + mutex_lock(&queue->lock); + + if (queue->streaming) + goto done; + + queue->streaming = 1; + + spin_lock_irqsave(&queue->irqlock, flags); + list_for_each_entry(buf, &queue->queue, stream) + queue->ops->buffer_queue(buf); + spin_unlock_irqrestore(&queue->irqlock, flags); + +done: + mutex_unlock(&queue->lock); + return 0; +} + +/** + * omap3isp_video_queue_streamoff - Stop streaming + * + * This function is intended to be used as a VIDIOC_STREAMOFF ioctl handler. It + * stops streaming on the queue and wakes up all the buffers. + * + * Drivers must stop the hardware and synchronize with interrupt handlers and/or + * delayed works before calling this function to make sure no buffer will be + * touched by the driver and/or hardware. + */ +void omap3isp_video_queue_streamoff(struct isp_video_queue *queue) +{ + struct isp_video_buffer *buf; + unsigned long flags; + unsigned int i; + + mutex_lock(&queue->lock); + + if (!queue->streaming) + goto done; + + queue->streaming = 0; + + spin_lock_irqsave(&queue->irqlock, flags); + for (i = 0; i < queue->count; ++i) { + buf = queue->buffers[i]; + + if (buf->state == ISP_BUF_STATE_ACTIVE) + wake_up(&buf->wait); + + buf->state = ISP_BUF_STATE_IDLE; + } + spin_unlock_irqrestore(&queue->irqlock, flags); + + INIT_LIST_HEAD(&queue->queue); + +done: + mutex_unlock(&queue->lock); +} + +/** + * omap3isp_video_queue_discard_done - Discard all buffers marked as DONE + * + * This function is intended to be used with suspend/resume operations. It + * discards all 'done' buffers as they would be too old to be requested after + * resume. + * + * Drivers must stop the hardware and synchronize with interrupt handlers and/or + * delayed works before calling this function to make sure no buffer will be + * touched by the driver and/or hardware. + */ +void omap3isp_video_queue_discard_done(struct isp_video_queue *queue) +{ + struct isp_video_buffer *buf; + unsigned int i; + + mutex_lock(&queue->lock); + + if (!queue->streaming) + goto done; + + for (i = 0; i < queue->count; ++i) { + buf = queue->buffers[i]; + + if (buf->state == ISP_BUF_STATE_DONE) + buf->state = ISP_BUF_STATE_ERROR; + } + +done: + mutex_unlock(&queue->lock); +} + +static void isp_video_queue_vm_open(struct vm_area_struct *vma) +{ + struct isp_video_buffer *buf = vma->vm_private_data; + + buf->vma_use_count++; +} + +static void isp_video_queue_vm_close(struct vm_area_struct *vma) +{ + struct isp_video_buffer *buf = vma->vm_private_data; + + buf->vma_use_count--; +} + +static const struct vm_operations_struct isp_video_queue_vm_ops = { + .open = isp_video_queue_vm_open, + .close = isp_video_queue_vm_close, +}; + +/** + * omap3isp_video_queue_mmap - Map buffers to userspace + * + * This function is intended to be used as an mmap() file operation handler. It + * maps a buffer to userspace based on the VMA offset. + * + * Only buffers of memory type MMAP are supported. + */ +int omap3isp_video_queue_mmap(struct isp_video_queue *queue, + struct vm_area_struct *vma) +{ + struct isp_video_buffer *uninitialized_var(buf); + unsigned long size; + unsigned int i; + int ret = 0; + + mutex_lock(&queue->lock); + + for (i = 0; i < queue->count; ++i) { + buf = queue->buffers[i]; + if ((buf->vbuf.m.offset >> PAGE_SHIFT) == vma->vm_pgoff) + break; + } + + if (i == queue->count) { + ret = -EINVAL; + goto done; + } + + size = vma->vm_end - vma->vm_start; + + if (buf->vbuf.memory != V4L2_MEMORY_MMAP || + size != PAGE_ALIGN(buf->vbuf.length)) { + ret = -EINVAL; + goto done; + } + + ret = remap_vmalloc_range(vma, buf->vaddr, 0); + if (ret < 0) + goto done; + + vma->vm_ops = &isp_video_queue_vm_ops; + vma->vm_private_data = buf; + isp_video_queue_vm_open(vma); + +done: + mutex_unlock(&queue->lock); + return ret; +} + +/** + * omap3isp_video_queue_poll - Poll video queue state + * + * This function is intended to be used as a poll() file operation handler. It + * polls the state of the video buffer at the front of the queue and returns an + * events mask. + * + * If no buffer is present at the front of the queue, POLLERR is returned. + */ +unsigned int omap3isp_video_queue_poll(struct isp_video_queue *queue, + struct file *file, poll_table *wait) +{ + struct isp_video_buffer *buf; + unsigned int mask = 0; + + mutex_lock(&queue->lock); + if (list_empty(&queue->queue)) { + mask |= POLLERR; + goto done; + } + buf = list_first_entry(&queue->queue, struct isp_video_buffer, stream); + + poll_wait(file, &buf->wait, wait); + if (buf->state == ISP_BUF_STATE_DONE || + buf->state == ISP_BUF_STATE_ERROR) { + if (queue->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) + mask |= POLLIN | POLLRDNORM; + else + mask |= POLLOUT | POLLWRNORM; + } + +done: + mutex_unlock(&queue->lock); + return mask; +} |