RE: [PATCH] drm/amdgpu:resolv deadlock between reset and cs_ioctl

> The order of job->base.s_fence and preventing concurrent CS was guaranteed by > the VM PD being reserved, that is now no longer the case and we need a new > lock for protection. Thought of this either, but since UMD/APP submits their jobs in one thread upon one ctx (if submits jobs within

Re: [PATCH] drm/amd/display: Don't leak dc_stream_state.

On Fri, Sep 8, 2017 at 11:41 AM, Darren Salt wrote: > Noticed while playing “Valley”, which was causing some 8MB of leakage per > second. kmemleak listed many entries looking like this: > > unreferenced object 0x8802c2951800 (size 1024): > comm "Xorg", pid

Re: [PATCH] drm/amdgpu: fix amdgpu_vm_handle_moved as well

On 2017年09月11日 18:58, Christian König wrote: From: Christian König There is no guarantee that the last BO_VA actually needed an update. Good catch. One comment inline Additional to that all command submissions must wait for moved BOs to be cleared, not just the

Re: [PATCH] drm/amdgpu: fix VM sync with always valid BOs v2

On 2017年09月11日 17:04, Christian König wrote: NAK, as Roger pointed, the performance of Vulkan Dota2 drops from 72fps to 24fps. This patches will kill Per-vm-BO advantages, even drop to 1/3 of previous non-per-vm-bo. This is irrelevant and actually a foreseen consequence of per VM BOs. If

Re: [PATCH 2/4] drm/amdgpu: added api for stopping psp ring

On Mon, Sep 11, 2017 at 09:22:03AM +0800, Evan Quan wrote: > Change-Id: I53bcacd531d8df801a49acd0409c3f27b49fb1be > Signed-off-by: Evan Quan > --- > drivers/gpu/drm/amd/amdgpu/amdgpu_psp.c | 2 ++ > drivers/gpu/drm/amd/amdgpu/amdgpu_psp.h | 2 ++ >

Re: [PATCH] drm/amdgpu: fix VM sync with always valid BOs v2

Am 11.09.2017 um 11:10 schrieb zhoucm1: On 2017年09月11日 17:04, Christian König wrote: NAK, as Roger pointed, the performance of Vulkan Dota2 drops from 72fps to 24fps. This patches will kill Per-vm-BO advantages, even drop to 1/3 of previous non-per-vm-bo. This is irrelevant and actually

Re: [PATCH 1/4] drm/amdgpu: fixed raven psp cmd prepare and submit

Patch 1, 3 are Reviewed-by: Huang Rui With minor comments on Patch 2 and 4, with that fixed, please feel free to add Reviewed-by: Huang Rui Thanks, Rui On Mon, Sep 11, 2017 at 09:22:02AM +0800, Evan Quan wrote: > Change-Id:

RE: [PATCH] drm/amdgpu: fix VM sync with always valid BOs v2

Reviewed-by: Roger He Thanks Roger(Hongbo.He) -Original Message- From: amd-gfx [mailto:amd-gfx-boun...@lists.freedesktop.org] On Behalf Of Christian K?nig Sent: Monday, September 11, 2017 6:53 PM To: Zhou, David(ChunMing) ;

[PATCH] drm/amdgpu:resolv deadlock between reset and cs_ioctl

need to unreserve ttm bo before "cs_add_fence" and "entity_push_job" otherwise there will be deadlock between "recover_vram_from_shadow" and previous two routines on the ttm bo's resv lock. Change-Id: I9c18b677e474ce5b45a9cc24da3fa255d77b3d44 Signed-off-by: Monk Liu ---

Re: [PATCH 1/2] amdgpu: Only destroy fbdev framebuffer if it was initialized

Am 11.09.2017 um 10:10 schrieb Michel Dänzer: From: Michel Dänzer Fixes crash when trying to unload the amdgpu module before the fbdev framebuffer was initialized, which can happen since the DRM fbdev helper code supports deferred setup. Signed-off-by: Michel Dänzer

[PATCH 2/2] radeon: Only destroy fbdev framebuffer if it was initialized

From: Michel Dänzer Fixes crash when trying to unload the amdgpu module before the fbdev framebuffer was initialized, which can happen since the DRM fbdev helper code supports deferred setup. Signed-off-by: Michel Dänzer ---

Re: [PATCH] drm/amdgpu: fix VM sync with always valid BOs v2

NAK, as Roger pointed, the performance of Vulkan Dota2 drops from 72fps to 24fps. This patches will kill Per-vm-BO advantages, even drop to 1/3 of previous non-per-vm-bo. This is irrelevant and actually a foreseen consequence of per VM BOs. If the performance drops is in-acceptable then the

Re: [PATCH] drm/amdgpu:resolv deadlock between reset and cs_ioctl

Am 11.09.2017 um 11:02 schrieb Monk Liu: need to unreserve ttm bo before "cs_add_fence" and "entity_push_job" otherwise there will be deadlock between "recover_vram_from_shadow" and previous two routines on the ttm bo's resv lock. Change-Id: I9c18b677e474ce5b45a9cc24da3fa255d77b3d44

[PATCH] drm/amdgpu: fix amdgpu_vm_handle_moved as well

From: Christian König There is no guarantee that the last BO_VA actually needed an update. Additional to that all command submissions must wait for moved BOs to be cleared, not just the first one. Signed-off-by: Christian König ---

[PATCH 1/2] amdgpu: Only destroy fbdev framebuffer if it was initialized

From: Michel Dänzer Fixes crash when trying to unload the amdgpu module before the fbdev framebuffer was initialized, which can happen since the DRM fbdev helper code supports deferred setup. Signed-off-by: Michel Dänzer ---

Re: [PATCH] drm/amdgpu: fix VM sync with always valid BOs

Thanks for the review, please see some comments inline. Am 08.09.2017 um 23:12 schrieb Felix Kuehling: I think this change could use a little more explanation. I also have some ideas for simplifying the code and making it easier to understand. See comments inline. But it looks good to me

Re: [PATCH] drm/amdgpu: fix VM sync with always valid BOs v2

NAK, as Roger pointed, the performance of Vulkan Dota2 drops from 72fps to 24fps. This patches will kill Per-vm-BO advantages, even drop to 1/3 of previous non-per-vm-bo. all moved and relocated fence have already synced, we just need to catch the va mapping but which is CS itself required,

Re: [PATCH 4/4] drm/amdgpu: enable raven to load firmwares by psp at default

On Mon, Sep 11, 2017 at 09:22:05AM +0800, Evan Quan wrote: > Change-Id: I7a0427555b34111e4e7600aa1e8b9cae31b44af7 > Signed-off-by: Evan Quan > --- > drivers/gpu/drm/amd/amdgpu/amdgpu_psp.c | 2 -- > drivers/gpu/drm/amd/amdgpu/amdgpu_ucode.c | 2 +- > 2 files changed, 1

Re: [PATCH] drm/amdgpu: fix VM sync with always valid BOs v2

Ok then we have a misunderstanding here. This applies to all per VM BOs, not just kernel BOs. It's just that as long as the per VM BOs aren't used the handling is still correct and we don't have any updates to UMD BOs we implicitly wait on. Sorry I should have waited a bit more, but since

Re: [PATCH 1/2] dma-buf: make reservation_object_copy_fences rcu save

Am 10.09.2017 um 09:30 schrieb Maarten Lankhorst: Op 04-09-17 om 21:02 schreef Christian König: From: Christian König Stop requiring that the src reservation object is locked for this operation. Signed-off-by: Christian König ---

Re: [PATCH umr 1/4] Fix wave SGPR reading

Hi Nicolai, I don't get this patch, 'x' starts at 0 and goes to sgpr_size but that doesn't include the offset into the SGPR space right? I mean I get the patch in umr_read_sgprs() but in print_waves() won't that mean you're printing out SGPRS[0..size]? Or are you saying having the base

Re: [PATCH 1/2] dma-buf: make reservation_object_copy_fences rcu save

Op 11-09-17 om 14:53 schreef Christian König: > Am 10.09.2017 um 09:30 schrieb Maarten Lankhorst: >> Op 04-09-17 om 21:02 schreef Christian König: >>> From: Christian König >>> >>> Stop requiring that the src reservation object is locked for this operation. >>> >>>

RE: [PATCH] drm/amdgpu: fix VM sync with always valid BOs v2

My mean is you should add a condition in code to check if BO is kernel BO or not. I expect V3. Regards, David 发自坚果 Pro He, Roger 于 2017年9月11日 下午6:57写道： Reviewed-by: Roger He Thanks Roger(Hongbo.He) -Original Message- From: amd-gfx

Re: [PATCH] drm/amdgpu: fix VM sync with always valid BOs v2

It still doesn't make sense, I don't understand why we need all existed update fence for CS, which could implicitly contain unrelated fence next CS used. For moved list case, we already synced. We should explicitly sync the needed fence. For per VM BOs, we lack mapping fence, that's why VM

Re: [PATCH] drm/amdgpu: fix VM sync with always valid BOs v2

I don't understand why we need all existed update fence for CS We don't need all updates for CS, we just need all updates for per VM BOs for CS because we don't know which BOs are used in the CS. That's the overall problem of using per VM BOs, the kernel doesn't know what is actually used by

[PATCH] drm/amdgpu: fix VM sync with always valid BOs v2

From: Christian König All users of a VM must always wait for updates with always valid BOs to be completed. v2: remove debugging leftovers, rename struct member Signed-off-by: Christian König --- drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c | 10

Re: [PATCH 1/4] drm/amdgpu: fixed raven psp cmd prepare and submit

Am 11.09.2017 um 03:42 schrieb Zhang, Jerry (Junwei): On 09/11/2017 09:22 AM, Evan Quan wrote: Change-Id: I9b7ebc99b7c75c03fb46d16c4c49348dd551325e Signed-off-by: Evan Quan The series patches is Reviewed-by: Junwei Zhang A bit more commit message

Re: [PATCH 2/2] drm/amdgpu: move MMU notifier related defines to amdgpu_mn.h

Am 11.09.2017 um 02:55 schrieb Michel Dänzer: On 09/09/17 12:52 AM, Christian König wrote: From: Christian König Just some cleanup. Signed-off-by: Christian König --- drivers/gpu/drm/amd/amdgpu/amdgpu.h| 25 +---

Re: [PATCH] drm/amdgpu/gfx9: implement wave VGPR reading

Am 09.09.2017 um 12:49 schrieb Nicolai Hähnle: From: Nicolai Hähnle This is already hooked up to the "amdgpu_gpr" debugfs file used by the umr userspace debugging tool. Signed-off-by: Nicolai Hähnle Acked-by: Christian König

RE: [PATCH libdrm] amdgpu: make userptr unit test more interesting

> -Original Message- > From: amd-gfx [mailto:amd-gfx-boun...@lists.freedesktop.org] On Behalf > Of Christian König > Sent: Thursday, September 07, 2017 4:17 AM > To: amd-gfx@lists.freedesktop.org > Subject: [PATCH libdrm] amdgpu: make userptr unit test more interesting > > From: Christian

[PATCH] drm/amdgpu: fix amdgpu_vm_handle_moved as well v2

From: Christian König There is no guarantee that the last BO_VA actually needed an update. Additional to that all command submissions must wait for moved BOs to be cleared, not just the first one. v2: Don't overwrite any newer fence. Signed-off-by: Christian König

Re: [PATCH 1/2] dma-buf: make reservation_object_copy_fences rcu save

Am 11.09.2017 um 17:13 schrieb Maarten Lankhorst: Op 11-09-17 om 16:45 schreef Christian König: Am 11.09.2017 um 15:56 schrieb Maarten Lankhorst: Op 11-09-17 om 14:53 schreef Christian König: Am 10.09.2017 um 09:30 schrieb Maarten Lankhorst: [SNIP] To be honest that looks rather ugly to me

[PATCH] drm/amd/powerplay: remove unnecessary call to memset

call to memset to assign 0 value immediately after allocating memory with kzalloc is unnecesaary as kzalloc allocates the memory filled with 0 value. Semantic patch used to resolve this issue: @@ expression e,e2; constant c; statement S; @@ e = kzalloc(e2, c); if(e == NULL) S - memset(e, 0,

Re: [PATCH 1/2] drm/amdgpu: add support for request SI/CI firmware in CGS

On Fri, Sep 8, 2017 at 2:40 AM, Rex Zhu wrote: > Change-Id: If3ab520f8c65bec070e97cd8787041919d687ad3 > Signed-off-by: Rex Zhu Series is: Reviewed-by: Alex Deucher > --- > drivers/gpu/drm/amd/amdgpu/amdgpu_cgs.c | 79 >

Re: [PATCH 1/2] dma-buf: make reservation_object_copy_fences rcu save

Am 11.09.2017 um 15:56 schrieb Maarten Lankhorst: Op 11-09-17 om 14:53 schreef Christian König: Am 10.09.2017 um 09:30 schrieb Maarten Lankhorst: Op 04-09-17 om 21:02 schreef Christian König: From: Christian König Stop requiring that the src reservation object is

Re: [PATCH 1/2] dma-buf: make reservation_object_copy_fences rcu save

Op 11-09-17 om 16:45 schreef Christian König: > Am 11.09.2017 um 15:56 schrieb Maarten Lankhorst: >> Op 11-09-17 om 14:53 schreef Christian König: >>> Am 10.09.2017 um 09:30 schrieb Maarten Lankhorst: Op 04-09-17 om 21:02 schreef Christian König: > From: Christian König

[PATCH] Audio output doesn't work on HDMI and DP ports of my MSI RX 460 2G OC.

From: Jan Andres The line in question seems to assume some kind of correlation between the numbering of the audio converters and the stream encoders, which doesn't exist on my card: Here, the active stream encoders are indexed 2 and 3 while audios have index 0 and 1, so audio

Re: [PATCH 1/2] amdgpu: Only destroy fbdev framebuffer if it was initialized

On Mon, Sep 11, 2017 at 4:24 AM, Christian König wrote: > Am 11.09.2017 um 10:10 schrieb Michel Dänzer: >> >> From: Michel Dänzer >> >> Fixes crash when trying to unload the amdgpu module before the fbdev >> framebuffer was initialized, which can

Re: [PATCH umr 1/4] Fix wave SGPR reading

On 11.09.2017 15:31, Tom St Denis wrote: Hi Nicolai, I don't get this patch, 'x' starts at 0 and goes to sgpr_size but that doesn't include the offset into the SGPR space right? I mean I get the patch in umr_read_sgprs() but in print_waves() won't that mean you're printing out

Re: [PATCH 1/2] dma-buf: make reservation_object_copy_fences rcu save

Am 11.09.2017 um 17:22 schrieb Christian König: Am 11.09.2017 um 17:13 schrieb Maarten Lankhorst: Op 11-09-17 om 16:45 schreef Christian König: Am 11.09.2017 um 15:56 schrieb Maarten Lankhorst: Op 11-09-17 om 14:53 schreef Christian König: Am 10.09.2017 um 09:30 schrieb Maarten Lankhorst:

Re: [PATCH 1/2] dma-buf: make reservation_object_copy_fences rcu save

Op 11-09-17 om 17:24 schreef Christian König: > Am 11.09.2017 um 17:22 schrieb Christian König: >> Am 11.09.2017 um 17:13 schrieb Maarten Lankhorst: >>> Op 11-09-17 om 16:45 schreef Christian König: Am 11.09.2017 um 15:56 schrieb Maarten Lankhorst: > Op 11-09-17 om 14:53 schreef Christian

RE: [PATCH 0/8] Retry page fault handling for Vega10

> -Original Message- > From: Kuehling, Felix > Sent: Wednesday, September 06, 2017 5:54 PM > To: amd-gfx@lists.freedesktop.org; Deucher, Alexander; Oded Gabbay; > Koenig, Christian > Subject: Re: [PATCH 0/8] Retry page fault handling for Vega10 > > I realized that the drm-next-4.15-wip

[PATCH] drm/amdgpu: revert tile table update for oland

Several users have complained that the tile table update broke Oland support. Despite several attempts to fix it, the root cause is still unknown at this point and no solution is available. As it is not acceptable to leave a known regression breaking a major functionality in the kernel for several

RE: [PATCH 2/6] Reorganize, rename, move and split some VCE 1 defines.

> -Original Message- > From: amd-gfx [mailto:amd-gfx-boun...@lists.freedesktop.org] On Behalf > Of Alexandre Demers > Sent: Thursday, September 07, 2017 10:49 PM > To: amd-gfx@lists.freedesktop.org > Subject: [PATCH 2/6] Reorganize, rename, move and split some VCE 1 > defines. > > For

RE: [PATCH 1/6] Add initial VCE_V1_0 files.

> -Original Message- > From: amd-gfx [mailto:amd-gfx-boun...@lists.freedesktop.org] On Behalf > Of Alexandre Demers > Sent: Thursday, September 07, 2017 10:49 PM > To: amd-gfx@lists.freedesktop.org > Subject: [PATCH 1/6] Add initial VCE_V1_0 files. > > Signed-off-by: Alexandre Demers

Re: [PATCH 1/2] dma-buf: make reservation_object_copy_fences rcu save

Am 11.09.2017 um 17:29 schrieb Maarten Lankhorst: Op 11-09-17 om 17:24 schreef Christian König: Am 11.09.2017 um 17:22 schrieb Christian König: Am 11.09.2017 um 17:13 schrieb Maarten Lankhorst: Op 11-09-17 om 16:45 schreef Christian König: Am 11.09.2017 um 15:56 schrieb Maarten Lankhorst:

[PATCH 02/28] drm/amd/display: Added negative check for vertical line start.

From: Yongqiang Sun In case of vstartup happens before vsync, set vertical line start to 0. Signed-off-by: Yongqiang Sun Reviewed-by: Tony Cheng Acked-by: Harry Wentland ---

[PATCH 08/28] drm/amd/display: set CP2520 Test pattern to use DP_TEST_PATTERN_HBR2_COMPLIANCE_EYE

From: Wenjing Liu Signed-off-by: Wenjing Liu Reviewed-by: Tony Cheng Acked-by: Harry Wentland --- drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff

[PATCH 05/28] drm/amd/display: Request to have DCN RV pipe Harvesting

From: Hersen Wu TODO: Current change only work for sucessive last fused pipe, like p3, or p3,p2. It does not work for fused p1,p2. Signed-off-by: Hersen Wu Reviewed-by: Tony Cheng Acked-by: Harry Wentland

[PATCH 18/28] drm/amd/display: move dwb registers to header file

From: Yue Hin Lau Signed-off-by: Yue Hin Lau Reviewed-by: Tony Cheng Acked-by: Harry Wentland --- drivers/gpu/drm/amd/display/dc/dcn10/dcn10_dwb.c | 288 +

[PATCH 11/28] drm/amd/display: fix default dithering

From: Tony Cheng bug: default is mapped to no dithering. default to spatial dithering based on color depth Signed-off-by: Tony Cheng Reviewed-by: Tony Cheng Acked-by: Harry Wentland ---

[PATCH 13/28] drm/amd/display: seperate dpp_cm_helper functions into new file

From: Yue Hin Lau Signed-off-by: Yue Hin Lau Reviewed-by: Tony Cheng Acked-by: Harry Wentland --- drivers/gpu/drm/amd/display/dc/dcn10/Makefile | 2 +- drivers/gpu/drm/amd/display/dc/dcn10/dcn10_dpp.h

[PATCH 00/28] DC Linux Patches Sep 11, 2017

* Bunch of Raven fixes and other work * Stop powering down clock sources in atomic check * Stop using amdgpu_connector and use our own * Fix display unplug during S3 or fbcon Andrew Jiang (1): drm/amd/display: Fix context alloc failed logging Charlene Liu (1): drm/amd/display: fix

[PATCH 17/28] drm/amd/display: remove output_format from ipp_setup

From: Eric Bernstein Signed-off-by: Eric Bernstein Reviewed-by: Tony Cheng Acked-by: Harry Wentland --- drivers/gpu/drm/amd/display/dc/dcn10/dcn10_dpp.c | 3 +--

[PATCH 03/28] drm/amd/display: Remove sanity check.

From: Yongqiang Sun Signed-off-by: Yongqiang Sun Reviewed-by: Tony Cheng Acked-by: Harry Wentland --- drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c | 6 -- 1 file changed, 6 deletions(-)

[PATCH 12/28] drm/amd/display: Fix context alloc failed logging

From: Andrew Jiang Since there was no return statement in the fail block immediately preceding the context_alloc_fail block, any failure within the function caused a context alloc failed error message to be printed. Since the context_alloc_fail block is only used once, move

[PATCH 01/28] drm/amd/display: Get OTG info if OTG master enabled

From: Logatharshan Thothiralingam Signed-off-by: Logatharshan Thothiralingam Reviewed-by: Tony Cheng Acked-by: Harry Wentland ---

[PATCH 14/28] drm/amd/display: Don't reset clock source at unref

Powering down the clock source during unref is unsafe as we might want to unref during atomic_check Signed-off-by: Harry Wentland Reviewed-by: Tony Cheng Acked-by: Harry Wentland ---

[PATCH 06/28] drm/amd/display: dce110: fix plane validation

From: Shirish S For MPO to work with per surface rendering and flipping, the previous logic of restricting plane[1] only as underlay needs to be removed. validate_surface_sets() now checks only the width and height bounds in case of underlay rather than checking format.

[PATCH 16/28] drm/amd/display: Remove switching of clk sources at end of commit

This should be taken care of in validate now. All of timing sync is quite broken at the moment anyways. Will submit another patch set to address that. Signed-off-by: Harry Wentland Reviewed-by: Andrey Grodzovsky Reviewed-by: Tony Cheng

[PATCH 15/28] drm/amd/display: Power down clock source at commit

Still one more in dc_validate_global Signed-off-by: Harry Wentland Reviewed-by: Tony Cheng Acked-by: Harry Wentland --- drivers/gpu/drm/amd/display/dc/core/dc_resource.c | 19 ++---

[PATCH 07/28] drm/amd/display: USB-C to HDMI dongle not light

From: Hersen Wu Signed-off-by: Hersen Wu Reviewed-by: Tony Cheng Acked-by: Harry Wentland --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 9 --- drivers/gpu/drm/amd/display/dc/core/dc_link.c

[PATCH 04/28] drm/amd/display: Use TPS4 instead of CP2520_3 for phy pattern 7

From: Wenjing Liu [Description] We originally use TPS4 phy test pattern for test pattern 7. On RV we switched to a new method to use CP2520. CP2520 should produce the same result. However in reality, it fails DP PHY automation test. We use the original method instead.

[PATCH 09/28] drm/amd/display: fix crc_source_select use hardcoded color depth

From: Charlene Liu Signed-off-by: Charlene Liu Reviewed-by: Tony Cheng Acked-by: Harry Wentland --- .../drm/amd/display/dc/dce110/dce110_hw_sequencer.c | 20 +++- 1 file changed, 19

[PATCH 10/28] drm/amd/display: Enable dcn10_power_on_fe log by default

This should only happen on full update. If this ever happens on regular pageflips it needs to be debugged. Signed-off-by: Harry Wentland Reviewed-by: Tony Cheng Acked-by: Harry Wentland ---

Re: [PATCH 0/8] Retry page fault handling for Vega10

On Mon, Sep 11, 2017 at 10:29 PM, Deucher, Alexander wrote: >> -Original Message- >> From: Kuehling, Felix >> Sent: Wednesday, September 06, 2017 5:54 PM >> To: amd-gfx@lists.freedesktop.org; Deucher, Alexander; Oded Gabbay; >> Koenig, Christian >> Subject: Re:

Re: [PATCH] drm/amd/powerplay: remove unnecessary call to memset

On Mon, Sep 11, 2017 at 8:37 AM, Himanshu Jha wrote: > call to memset to assign 0 value immediately after allocating > memory with kzalloc is unnecesaary as kzalloc allocates the memory > filled with 0 value. > > Semantic patch used to resolve this issue: > > @@ >

[PATCH v2] drm/amd/display: USB-C to HDMI dongle not light

From: Hersen Wu RV1 support only USB-C active DP-2-HDMI dongle. HPD short pulse is generated only for DP signal. When processing HPD short pulse, it must be DP active dongle. No need for I2C-Over-AUX detection. v2: Add description Signed-off-by: Hersen Wu

Re: [PATCH 07/28] drm/amd/display: USB-C to HDMI dongle not light

This seems to lack a commit msg Dave. On 12 Sep. 2017 4:15 am, "Harry Wentland" wrote: > From: Hersen Wu > > Signed-off-by: Hersen Wu > Reviewed-by: Tony Cheng > Acked-by: Harry Wentland