Commit Graph

15 Commits

Author SHA1 Message Date
Jan Kara 5a9e4dec39 [media] media: vb2: Convert vb2_vmalloc_get_userptr() to use frame vector
Convert vb2_vmalloc_get_userptr() to use frame vector infrastructure.
When we are doing that there's no need to allocate page array and some
code can be simplified.

Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
2015-08-16 13:13:06 -03:00
Jan Kara 0f6e2825ce [media] vb2: Push mmap_sem down to memops
Currently vb2 core acquires mmap_sem just around call to
__qbuf_userptr(). However since commit f035eb4e97 (videobuf2: fix
lockdep warning) it isn't necessary to acquire it so early as we no
longer have to drop queue mutex before acquiring mmap_sem. So push
acquisition of mmap_sem down into .get_userptr memop so that the
semaphore is acquired for a shorter time and it is clearer what it is
needed for.

Note that we also need mmap_sem in .put_userptr memop since that ends up
calling vb2_put_vma() which calls vma->vm_ops->close() which should be
called with mmap_sem held. However we didn't hold mmap_sem in some code
paths anyway (e.g. when called via vb2_ioctl_reqbufs() ->
__vb2_queue_free() -> vb2_dma_sg_put_userptr()) and getting mmap_sem in
put_userptr() introduces a lock inversion with queue->mmap_lock in the
above mentioned call path.

Luckily this whole locking mess will get resolved once we convert
videobuf2 core to the new mm helper which avoids the need for mmap_sem
in .put_userptr memop altogether.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
2015-08-16 13:01:10 -03:00
Hans Verkuil 511a1b8a4c [media] Revert "[media] vb2: Push mmap_sem down to memops"
This reverts commit 48b25a3a71.

That commit caused two regressions. The first is a BUG:

Jun 14 18:42:15 test-media kernel: [  115.972299] BUG: unable to handle kernel NULL pointer dereference at 0000000000000100
Jun 14 18:42:15 test-media kernel: [  115.972307] IP: [<ffffffff810d5cd0>] __lock_acquire+0x2f0/0x2070
Jun 14 18:42:15 test-media kernel: [  115.972316] PGD 0
Jun 14 18:42:15 test-media kernel: [  115.972318] Oops: 0000 [#1] PREEMPT SMP
Jun 14 18:42:15 test-media kernel: [  115.972321] Modules linked in: vivid v4l2_dv_timings videobuf2_vmalloc videobuf2_memops videobuf2_core v4l2_common videodev media vmw_balloon vmw_vmci acpi_cpufreq processor button
Jun 14 18:42:15 test-media kernel: [  115.972333] CPU: 0 PID: 1542 Comm: v4l2-ctl Not tainted 4.1.0-rc3-test-media #1190
Jun 14 18:42:15 test-media kernel: [  115.972336] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 05/20/2014
Jun 14 18:42:15 test-media kernel: [  115.972337] task: ffff880220ce4200 ti: ffff88021d16c000 task.ti: ffff88021d16c000
Jun 14 18:42:15 test-media kernel: [  115.972339] RIP: 0010:[<ffffffff810d5cd0>]  [<ffffffff810d5cd0>] __lock_acquire+0x2f0/0x2070
Jun 14 18:42:15 test-media kernel: [  115.972342] RSP: 0018:ffff88021d16f9b8  EFLAGS: 00010002
Jun 14 18:42:15 test-media kernel: [  115.972343] RAX: 0000000000000046 RBX: 0000000000000292 RCX: 0000000000000001
Jun 14 18:42:15 test-media kernel: [  115.972345] RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000100
Jun 14 18:42:15 test-media kernel: [  115.972346] RBP: ffff88021d16fa88 R08: 0000000000000001 R09: 0000000000000000
Jun 14 18:42:15 test-media kernel: [  115.972347] R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000001
Jun 14 18:42:15 test-media kernel: [  115.972348] R13: ffff880220ce4200 R14: 0000000000000100 R15: 0000000000000000
Jun 14 18:42:15 test-media kernel: [  115.972350] FS:  00007f2441e7f740(0000) GS:ffff880236e00000(0000) knlGS:0000000000000000
Jun 14 18:42:15 test-media kernel: [  115.972351] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
Jun 14 18:42:15 test-media kernel: [  115.972353] CR2: 0000000000000100 CR3: 0000000001e0b000 CR4: 00000000001406f0
Jun 14 18:42:15 test-media kernel: [  115.972424] Stack:
Jun 14 18:42:15 test-media kernel: [  115.972427]  ffff88021d16fa98 ffffffff810d6543 0000000000000006 0000000000000246
Jun 14 18:42:15 test-media kernel: [  115.972431]  ffff88021d16fa08 ffffffff810d532d ffff880220ce4a78 ffff880200000000
Jun 14 18:42:15 test-media kernel: [  115.972433]  ffff880200000001 0000000000000000 0000000000000001 000000000093a4a0
Jun 14 18:42:15 test-media kernel: [  115.972436] Call Trace:
Jun 14 18:42:15 test-media kernel: [  115.972440]  [<ffffffff810d6543>] ? __lock_acquire+0xb63/0x2070
Jun 14 18:42:15 test-media kernel: [  115.972443]  [<ffffffff810d532d>] ? mark_held_locks+0x6d/0xa0
Jun 14 18:42:15 test-media kernel: [  115.972445]  [<ffffffff810d37a8>] ? __lock_is_held+0x58/0x80
Jun 14 18:42:15 test-media kernel: [  115.972447]  [<ffffffff810d852c>] lock_acquire+0x6c/0xa0
Jun 14 18:42:15 test-media kernel: [  115.972452]  [<ffffffffa039f1f6>] ? vb2_vmalloc_put_userptr+0x36/0x110 [videobuf2_vmalloc]
Jun 14 18:42:15 test-media kernel: [  115.972458]  [<ffffffff819b1a92>] down_read+0x42/0x60
Jun 14 18:42:15 test-media kernel: [  115.972460]  [<ffffffffa039f1f6>] ? vb2_vmalloc_put_userptr+0x36/0x110 [videobuf2_vmalloc]
Jun 14 18:42:15 test-media kernel: [  115.972463]  [<ffffffff819af1b1>] ? mutex_lock_nested+0x2b1/0x560
Jun 14 18:42:15 test-media kernel: [  115.972467]  [<ffffffffa038fdc5>] ? vb2_queue_release+0x25/0x40 [videobuf2_core]
Jun 14 18:42:15 test-media kernel: [  115.972469]  [<ffffffffa039f1f6>] vb2_vmalloc_put_userptr+0x36/0x110 [videobuf2_vmalloc]
Jun 14 18:42:15 test-media kernel: [  115.972472]  [<ffffffffa038b626>] __vb2_queue_free+0x146/0x5e0 [videobuf2_core]
Jun 14 18:42:15 test-media kernel: [  115.972475]  [<ffffffffa038fdd3>] vb2_queue_release+0x33/0x40 [videobuf2_core]
Jun 14 18:42:15 test-media kernel: [  115.972478]  [<ffffffffa038fe75>] _vb2_fop_release+0x95/0xb0 [videobuf2_core]
Jun 14 18:42:15 test-media kernel: [  115.972481]  [<ffffffffa038feb9>] vb2_fop_release+0x29/0x50 [videobuf2_core]
Jun 14 18:42:15 test-media kernel: [  115.972485]  [<ffffffffa03ad372>] vivid_fop_release+0x92/0x230 [vivid]
Jun 14 18:42:15 test-media kernel: [  115.972491]  [<ffffffffa0358460>] v4l2_release+0x30/0x80 [videodev]
Jun 14 18:42:15 test-media kernel: [  115.972496]  [<ffffffff811a51d5>] __fput+0xe5/0x200
Jun 14 18:42:15 test-media kernel: [  115.972498]  [<ffffffff811a5339>] ____fput+0x9/0x10
Jun 14 18:42:15 test-media kernel: [  115.972501]  [<ffffffff810a9fa4>] task_work_run+0xc4/0xf0
Jun 14 18:42:15 test-media kernel: [  115.972504]  [<ffffffff8108c670>] do_exit+0x3a0/0xaf0
Jun 14 18:42:15 test-media kernel: [  115.972507]  [<ffffffff819b3a9b>] ? _raw_spin_unlock_irq+0x2b/0x60
Jun 14 18:42:15 test-media kernel: [  115.972509]  [<ffffffff8108e0ff>] do_group_exit+0x4f/0xe0
Jun 14 18:42:15 test-media kernel: [  115.972511]  [<ffffffff8109a170>] get_signal+0x200/0x8c0
Jun 14 18:42:15 test-media kernel: [  115.972514]  [<ffffffff819b14b5>] ? __mutex_unlock_slowpath+0xf5/0x240
Jun 14 18:42:15 test-media kernel: [  115.972518]  [<ffffffff81002593>] do_signal+0x23/0x820
Jun 14 18:42:15 test-media kernel: [  115.972521]  [<ffffffff819b1609>] ? mutex_unlock+0x9/0x10
Jun 14 18:42:15 test-media kernel: [  115.972524]  [<ffffffffa0358648>] ? v4l2_ioctl+0x78/0xf0 [videodev]
Jun 14 18:42:15 test-media kernel: [  115.972526]  [<ffffffff819b4653>] ? int_very_careful+0x5/0x46
Jun 14 18:42:15 test-media kernel: [  115.972529]  [<ffffffff810d54bd>] ? trace_hardirqs_on_caller+0x15d/0x200
Jun 14 18:42:15 test-media kernel: [  115.972531]  [<ffffffff81002de0>] do_notify_resume+0x50/0x60
Jun 14 18:42:15 test-media kernel: [  115.972533]  [<ffffffff819b46a6>] int_signal+0x12/0x17
Jun 14 18:42:15 test-media kernel: [  115.972534] Code: ca 81 31 c0 e8 7a e2 8c 00 e8 aa 1d 8d 00 0f 1f 44 00 00 31 db 48 81 c4 a8 00 00 00 89 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 66 90 <49> 81 3e 40 4e 02 82 b8 00 00 00 00 44 0f 44 e0 41 83 ff 01 0f
Jun 14 18:42:15 test-media kernel: [  115.972567] RIP  [<ffffffff810d5cd0>] __lock_acquire+0x2f0/0x2070
Jun 14 18:42:15 test-media kernel: [  115.972569]  RSP <ffff88021d16f9b8>
Jun 14 18:42:15 test-media kernel: [  115.972570] CR2: 0000000000000100
Jun 14 18:42:15 test-media kernel: [  115.972573] ---[ end trace 25595c2b8560cb57 ]---
Jun 14 18:42:15 test-media kernel: [  115.972575] Fixing recursive fault but reboot is needed!

This can be reproduced by loading the vivid driver and running:

v4l2-ctl --stream-user

and pressing Ctrl-C. You may have to try a few times, but in my experience this BUG
is triggered quite quickly.

The second is a possible deadlock:

Jun 14 18:44:07 test-media kernel: [   49.376650] ======================================================
Jun 14 18:44:07 test-media kernel: [   49.376651] [ INFO: possible circular locking dependency detected ]
Jun 14 18:44:07 test-media kernel: [   49.376653] 4.1.0-rc3-test-media #1190 Not tainted
Jun 14 18:44:07 test-media kernel: [   49.376654] -------------------------------------------------------
Jun 14 18:44:07 test-media kernel: [   49.376655] v4l2-compliance/1468 is trying to acquire lock:
Jun 14 18:44:07 test-media kernel: [   49.376657]  (&mm->mmap_sem){++++++}, at: [<ffffffffa03a81f6>] vb2_vmalloc_put_userptr+0x36/0x110 [videobuf2_vmalloc]
Jun 14 18:44:07 test-media kernel: [   49.376665]
Jun 14 18:44:07 test-media kernel: [   49.376665] but task is already holding lock:
Jun 14 18:44:07 test-media kernel: [   49.376666]  (&q->mmap_lock){+.+...}, at: [<ffffffffa0398dc5>] vb2_queue_release+0x25/0x40 [videobuf2_core]
Jun 14 18:44:07 test-media kernel: [   49.376670]
Jun 14 18:44:07 test-media kernel: [   49.376670] which lock already depends on the new lock.
Jun 14 18:44:07 test-media kernel: [   49.376670]
Jun 14 18:44:07 test-media kernel: [   49.376671]
Jun 14 18:44:07 test-media kernel: [   49.376671] the existing dependency chain (in reverse order) is:
Jun 14 18:44:07 test-media kernel: [   49.376672]
Jun 14 18:44:07 test-media kernel: [   49.376672] -> #1 (&q->mmap_lock){+.+...}:
Jun 14 18:44:07 test-media kernel: [   49.376675]        [<ffffffff810d852c>] lock_acquire+0x6c/0xa0
Jun 14 18:44:07 test-media kernel: [   49.376682]        [<ffffffff819aef5e>] mutex_lock_nested+0x5e/0x560
Jun 14 18:44:07 test-media kernel: [   49.376689]        [<ffffffffa03934a2>] vb2_mmap+0x232/0x350 [videobuf2_core]
Jun 14 18:44:07 test-media kernel: [   49.376691]        [<ffffffffa0395a60>] vb2_fop_mmap+0x20/0x30 [videobuf2_core]
Jun 14 18:44:07 test-media kernel: [   49.376694]        [<ffffffffa0361102>] v4l2_mmap+0x52/0x90 [videodev]
Jun 14 18:44:07 test-media kernel: [   49.376698]        [<ffffffff81177e33>] mmap_region+0x3b3/0x5e0
Jun 14 18:44:07 test-media kernel: [   49.376701]        [<ffffffff81178377>] do_mmap_pgoff+0x317/0x400
Jun 14 18:44:07 test-media kernel: [   49.376703]        [<ffffffff81165320>] vm_mmap_pgoff+0x90/0xc0
Jun 14 18:44:07 test-media kernel: [   49.376708]        [<ffffffff81176867>] SyS_mmap_pgoff+0x1d7/0x280
Jun 14 18:44:07 test-media kernel: [   49.376709]        [<ffffffff81007f8d>] SyS_mmap+0x1d/0x20
Jun 14 18:44:07 test-media kernel: [   49.376714]        [<ffffffff819b44ae>] system_call_fastpath+0x12/0x76
Jun 14 18:44:07 test-media kernel: [   49.376716]
Jun 14 18:44:07 test-media kernel: [   49.376716] -> #0 (&mm->mmap_sem){++++++}:
Jun 14 18:44:07 test-media kernel: [   49.376718]        [<ffffffff810d79b3>] __lock_acquire+0x1fd3/0x2070
Jun 14 18:44:07 test-media kernel: [   49.376720]        [<ffffffff810d852c>] lock_acquire+0x6c/0xa0
Jun 14 18:44:07 test-media kernel: [   49.376721]        [<ffffffff819b1a92>] down_read+0x42/0x60
Jun 14 18:44:07 test-media kernel: [   49.376723]        [<ffffffffa03a81f6>] vb2_vmalloc_put_userptr+0x36/0x110 [videobuf2_vmalloc]
Jun 14 18:44:07 test-media kernel: [   49.376725]        [<ffffffffa0394626>] __vb2_queue_free+0x146/0x5e0 [videobuf2_core]
Jun 14 18:44:07 test-media kernel: [   49.376727]        [<ffffffffa0398dd3>] vb2_queue_release+0x33/0x40 [videobuf2_core]
Jun 14 18:44:07 test-media kernel: [   49.376729]        [<ffffffffa0398e75>] _vb2_fop_release+0x95/0xb0 [videobuf2_core]
Jun 14 18:44:07 test-media kernel: [   49.376731]        [<ffffffffa0398eb9>] vb2_fop_release+0x29/0x50 [videobuf2_core]
Jun 14 18:44:07 test-media kernel: [   49.376733]        [<ffffffffa03b6372>] vivid_fop_release+0x92/0x230 [vivid]
Jun 14 18:44:07 test-media kernel: [   49.376737]        [<ffffffffa0361460>] v4l2_release+0x30/0x80 [videodev]
Jun 14 18:44:07 test-media kernel: [   49.376739]        [<ffffffff811a51d5>] __fput+0xe5/0x200
Jun 14 18:44:07 test-media kernel: [   49.376744]        [<ffffffff811a5339>] ____fput+0x9/0x10
Jun 14 18:44:07 test-media kernel: [   49.376746]        [<ffffffff810a9fa4>] task_work_run+0xc4/0xf0
Jun 14 18:44:07 test-media kernel: [   49.376749]        [<ffffffff81002dd1>] do_notify_resume+0x41/0x60
Jun 14 18:44:07 test-media kernel: [   49.376752]        [<ffffffff819b46a6>] int_signal+0x12/0x17
Jun 14 18:44:07 test-media kernel: [   49.376754]
Jun 14 18:44:07 test-media kernel: [   49.376754] other info that might help us debug this:
Jun 14 18:44:07 test-media kernel: [   49.376754]
Jun 14 18:44:07 test-media kernel: [   49.376755]  Possible unsafe locking scenario:
Jun 14 18:44:07 test-media kernel: [   49.376755]
Jun 14 18:44:07 test-media kernel: [   49.376756]        CPU0                    CPU1
Jun 14 18:44:07 test-media kernel: [   49.376757]        ----                    ----
Jun 14 18:44:07 test-media kernel: [   49.376758]   lock(&q->mmap_lock);
Jun 14 18:44:07 test-media kernel: [   49.376759]                                lock(&mm->mmap_sem);
Jun 14 18:44:07 test-media kernel: [   49.376760]                                lock(&q->mmap_lock);
Jun 14 18:44:07 test-media kernel: [   49.376761]   lock(&mm->mmap_sem);
Jun 14 18:44:07 test-media kernel: [   49.376763]
Jun 14 18:44:07 test-media kernel: [   49.376763]  *** DEADLOCK ***
Jun 14 18:44:07 test-media kernel: [   49.376763]
Jun 14 18:44:07 test-media kernel: [   49.376764] 2 locks held by v4l2-compliance/1468:
Jun 14 18:44:07 test-media kernel: [   49.376765]  #0:  (&dev->mutex#3){+.+.+.}, at: [<ffffffffa0398e0a>] _vb2_fop_release+0x2a/0xb0 [videobuf2_core]
Jun 14 18:44:07 test-media kernel: [   49.376770]  #1:  (&q->mmap_lock){+.+...}, at: [<ffffffffa0398dc5>] vb2_queue_release+0x25/0x40 [videobuf2_core]
Jun 14 18:44:07 test-media kernel: [   49.376773]
Jun 14 18:44:07 test-media kernel: [   49.376773] stack backtrace:
Jun 14 18:44:07 test-media kernel: [   49.376776] CPU: 2 PID: 1468 Comm: v4l2-compliance Not tainted 4.1.0-rc3-test-media #1190
Jun 14 18:44:07 test-media kernel: [   49.376777] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 05/20/2014
Jun 14 18:44:07 test-media kernel: [   49.376779]  ffffffff8279e0b0 ffff88021d6f7ba8 ffffffff819a7aac 0000000000000011
Jun 14 18:44:07 test-media kernel: [   49.376781]  ffffffff8279e0b0 ffff88021d6f7bf8 ffffffff819a3964 ffff88021d6f7bd8
Jun 14 18:44:07 test-media kernel: [   49.376783]  ffff8800ac8aa100 0000000000000002 ffff8800ac8aa9a0 0000000000000002
Jun 14 18:44:07 test-media kernel: [   49.376785] Call Trace:
Jun 14 18:44:07 test-media kernel: [   49.376788]  [<ffffffff819a7aac>] dump_stack+0x4f/0x7b
Jun 14 18:44:07 test-media kernel: [   49.376792]  [<ffffffff819a3964>] print_circular_bug+0x20f/0x251
Jun 14 18:44:07 test-media kernel: [   49.376793]  [<ffffffff810d79b3>] __lock_acquire+0x1fd3/0x2070
Jun 14 18:44:07 test-media kernel: [   49.376795]  [<ffffffff810d6543>] ? __lock_acquire+0xb63/0x2070
Jun 14 18:44:07 test-media kernel: [   49.376797]  [<ffffffff810d37a8>] ? __lock_is_held+0x58/0x80
Jun 14 18:44:07 test-media kernel: [   49.376798]  [<ffffffff810d852c>] lock_acquire+0x6c/0xa0
Jun 14 18:44:07 test-media kernel: [   49.376800]  [<ffffffffa03a81f6>] ? vb2_vmalloc_put_userptr+0x36/0x110 [videobuf2_vmalloc]
Jun 14 18:44:07 test-media kernel: [   49.376802]  [<ffffffff819b1a92>] down_read+0x42/0x60
Jun 14 18:44:07 test-media kernel: [   49.376803]  [<ffffffffa03a81f6>] ? vb2_vmalloc_put_userptr+0x36/0x110 [videobuf2_vmalloc]
Jun 14 18:44:07 test-media kernel: [   49.376805]  [<ffffffff819af1b1>] ? mutex_lock_nested+0x2b1/0x560
Jun 14 18:44:07 test-media kernel: [   49.376807]  [<ffffffffa0398dc5>] ? vb2_queue_release+0x25/0x40 [videobuf2_core]
Jun 14 18:44:07 test-media kernel: [   49.376808]  [<ffffffffa03a81f6>] vb2_vmalloc_put_userptr+0x36/0x110 [videobuf2_vmalloc]
Jun 14 18:44:07 test-media kernel: [   49.376810]  [<ffffffffa0398e0a>] ? _vb2_fop_release+0x2a/0xb0 [videobuf2_core]
Jun 14 18:44:07 test-media kernel: [   49.376812]  [<ffffffffa0394626>] __vb2_queue_free+0x146/0x5e0 [videobuf2_core]
Jun 14 18:44:07 test-media kernel: [   49.376814]  [<ffffffffa0398dd3>] vb2_queue_release+0x33/0x40 [videobuf2_core]
Jun 14 18:44:07 test-media kernel: [   49.376816]  [<ffffffffa0398e75>] _vb2_fop_release+0x95/0xb0 [videobuf2_core]
Jun 14 18:44:07 test-media kernel: [   49.376818]  [<ffffffffa0398eb9>] vb2_fop_release+0x29/0x50 [videobuf2_core]
Jun 14 18:44:07 test-media kernel: [   49.376820]  [<ffffffffa03b6372>] vivid_fop_release+0x92/0x230 [vivid]
Jun 14 18:44:07 test-media kernel: [   49.376822]  [<ffffffffa0361460>] v4l2_release+0x30/0x80 [videodev]
Jun 14 18:44:07 test-media kernel: [   49.376824]  [<ffffffff811a51d5>] __fput+0xe5/0x200
Jun 14 18:44:07 test-media kernel: [   49.376825]  [<ffffffff819b4653>] ? int_very_careful+0x5/0x46
Jun 14 18:44:07 test-media kernel: [   49.376827]  [<ffffffff811a5339>] ____fput+0x9/0x10
Jun 14 18:44:07 test-media kernel: [   49.376828]  [<ffffffff810a9fa4>] task_work_run+0xc4/0xf0
Jun 14 18:44:07 test-media kernel: [   49.376830]  [<ffffffff81002dd1>] do_notify_resume+0x41/0x60
Jun 14 18:44:07 test-media kernel: [   49.376832]  [<ffffffff819b46a6>] int_signal+0x12/0x17

This can be triggered by loading the vivid module with the module option 'no_error_inj=1'
and running 'v4l2-compliance -s5'. Again, it may take a few attempts to trigger this
but for me it happens quite quickly.

Without this patch I cannot reproduce these two issues. So reverting is the best
solution for now.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
2015-06-18 14:34:22 -03:00
Ricardo Ribalda ba81c6ed3d [media] media/videobuf2-dma-vmalloc: Save output from dma_map_sg
dma_map_sg returns the number of areas mapped by the hardware,
which could be different than the areas given as an input.
The output must be saved to nent.

Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Reviewed-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
2015-05-30 11:31:10 -03:00
Jan Kara 48b25a3a71 [media] vb2: Push mmap_sem down to memops
Currently vb2 core acquires mmap_sem just around call to
__qbuf_userptr(). However since commit f035eb4e97 (videobuf2: fix
lockdep warning) it isn't necessary to acquire it so early as we no
longer have to drop queue mutex before acquiring mmap_sem. So push
acquisition of mmap_sem down into .get_userptr and .put_userptr memops
so that the semaphore is acquired for a shorter time and it is clearer
what it is needed for.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
2015-05-01 07:17:27 -03:00
Sumit Semwal d8fbe341be dma-buf: cleanup dma_buf_export() to make it easily extensible
At present, dma_buf_export() takes a series of parameters, which
makes it difficult to add any new parameters for exporters, if required.

Make it simpler by moving all these parameters into a struct, and pass
the struct * as parameter to dma_buf_export().

While at it, unite dma_buf_export_named() with dma_buf_export(), and
change all callers accordingly.

Reviewed-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Acked-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
2015-04-21 14:47:16 +05:30
Geert Uytterhoeven 99f3cd52ae [media] vb2-vmalloc: Protect DMA-specific code by #ifdef CONFIG_HAS_DMA
If NO_DMA=y:

drivers/built-in.o: In function `vb2_vmalloc_dmabuf_ops_detach':
videobuf2-vmalloc.c:(.text+0x6f11b0): undefined reference to `dma_unmap_sg'
drivers/built-in.o: In function `vb2_vmalloc_dmabuf_ops_map':
videobuf2-vmalloc.c:(.text+0x6f1266): undefined reference to `dma_unmap_sg'
videobuf2-vmalloc.c:(.text+0x6f1282): undefined reference to `dma_map_sg'

As we don't want to make the core VIDEOBUF2_VMALLOC depend on HAS_DMA
(it's v4l2 core code, and selected by a lot of drivers), stub out the
DMA support if HAS_DMA is not set.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
2014-12-23 16:28:09 -02:00
Hans Verkuil 7c424dd14f [media] videobuf2-vmalloc: fix sparse warning
Fix this warning:

drivers/media/v4l2-core/videobuf2-vmalloc.c:98:28: warning: incorrect type in assignment (different address spaces)
drivers/media/v4l2-core/videobuf2-vmalloc.c:158:28: warning: incorrect type in argument 1 (different address spaces)

The warning is correct, but we have no other choice here to forcibly cast.
At least it is now explicit that such a cast is needed.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
2014-12-23 10:41:43 -02:00
Markus Elfring 7c57529baa [media] V4L2: Deletion of an unnecessary check before the function call "vb2_put_vma"
The vb2_put_vma() function tests whether its argument is NULL and then
returns immediately. Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
2014-12-02 11:33:09 -02:00
Hans Verkuil 4650635069 [media] vb2-vmalloc: add support for dmabuf exports
Add support for DMABUF exporting to the vb2-vmalloc implementation.

All memory models now have support for both importing and exporting of DMABUFs.

Signed-off-by: Hans Verkuil <hansverk@cisco.com>
Acked-by: Pawel Osciak <pawel@osciak.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
2014-11-25 09:07:08 -02:00
Hans Verkuil d935c57e8f [media] vb2: add dma_dir to the alloc memop
This is needed for the next patch where the dma-sg alloc memop needs
to know the dma_dir.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Pawel Osciak <pawel@osciak.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
2014-11-25 08:51:44 -02:00
Hans Verkuil cd474037c4 [media] vb2: replace 'write' by 'dma_dir'
The 'write' argument is very ambiguous. I first assumed that if it is 1,
then we're doing video output but instead it meant the reverse.

Since it is used to setup the dma_dir value anyway it is now replaced by
the correct dma_dir value which is unambiguous.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Pawel Osciak <pawel@osciak.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
2014-11-25 08:50:28 -02:00
Hans Verkuil b6ba2057f7 [media] videobuf2: add gfp_flags
Some drivers have special memory requirements for their buffers, usually
related to DMA (e.g. GFP_DMA or __GFP_DMA32). Make it possible to specify
additional GFP flags for those buffers by adding a gfp_flags field to
vb2_queue.
Note that this field will be replaced in the future with a different
mechanism, but that is still work in progress and we need this feature
now so we won't be able to convert drivers with such requirements to vb2.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Federico Vaga <federico.vaga@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2013-03-21 13:17:51 -03:00
Tomasz Stanislawski 89d2ee0890 [media] v4l: vb2-vmalloc: add support for dmabuf importing
This patch adds support for importing DMABUF files for
vmalloc allocator in Videobuf2.

Signed-off-by: Tomasz Stanislawski <t.stanislaws@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Tested-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-11-25 17:18:58 -02:00
Mauro Carvalho Chehab 5bc3cb743b [media] v4l: move v4l2 core into a separate directory
Currently, the v4l2 core is mixed together with other non-core drivers.
Move them into a separate directory.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-08-13 23:02:38 -03:00