From f8669f1d6a86a6b17104ceca9340ded280307ac1 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Wed, 9 Mar 2022 19:49:26 -0800 Subject: nvdimm/blk: Delete the block-aperture window driver Block Aperture Window support was an attempt to layer an error model over PMEM for platforms that did not support machine-check-recovery. However, it was abandoned before it ever shipped, and only ever existed in the ACPI specification. Meanwhile Linux has carried a large pile of dead code for non-shipping infrastructure. For years it has been off to the side out of the way, but now CXL and recent directions with DAX support have the potential to collide with this code. In preparation for adding discontiguous namespace support, a pre-requisite for the nvdimm subsystem to replace device-mapper for striping + concatenation use cases, delete BLK aperture support. On the obscure chance that some hardware vendor shipped support for this mode, note that the driver will still keep BLK space reserved in the label area. So an end user in this case would still have the opportunity to report the regression to get BLK-mode support restored without risking the data they have on that device. Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/164688416668.2879318.16903178375774275120.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams --- drivers/nvdimm/Kconfig | 25 ++++--------------------- 1 file changed, 4 insertions(+), 21 deletions(-) (limited to 'drivers/nvdimm/Kconfig') diff --git a/drivers/nvdimm/Kconfig b/drivers/nvdimm/Kconfig index 347fe7afa583..5a29046e3319 100644 --- a/drivers/nvdimm/Kconfig +++ b/drivers/nvdimm/Kconfig @@ -10,12 +10,9 @@ menuconfig LIBNVDIMM ACPI-6-NFIT defined resources. On platforms that define an NFIT, or otherwise can discover NVDIMM resources, a libnvdimm bus is registered to advertise PMEM (persistent memory) - namespaces (/dev/pmemX) and BLK (sliding mmio window(s)) - namespaces (/dev/ndblkX.Y). A PMEM namespace refers to a + namespaces (/dev/pmemX). A PMEM namespace refers to a memory resource that may span multiple DIMMs and support DAX - (see CONFIG_DAX). A BLK namespace refers to an NVDIMM control - region which exposes an mmio register set for windowed access - mode to non-volatile memory. + (see CONFIG_DAX). if LIBNVDIMM @@ -38,19 +35,6 @@ config BLK_DEV_PMEM Say Y if you want to use an NVDIMM -config ND_BLK - tristate "BLK: Block data window (aperture) device support" - default LIBNVDIMM - select ND_BTT if BTT - help - Support NVDIMMs, or other devices, that implement a BLK-mode - access capability. BLK-mode access uses memory-mapped-i/o - apertures to access persistent media. - - Say Y if your platform firmware emits an ACPI.NFIT table - (CONFIG_ACPI_NFIT), or otherwise exposes BLK-mode - capabilities. - config ND_CLAIM bool @@ -67,9 +51,8 @@ config BTT applications that rely on sector writes not being torn (a guarantee that typical disks provide) can continue to do so. The BTT manifests itself as an alternate personality for an - NVDIMM namespace, i.e. a namespace can be in raw mode (pmemX, - ndblkX.Y, etc...), or 'sectored' mode, (pmemXs, ndblkX.Ys, - etc...). + NVDIMM namespace, i.e. a namespace can be in raw mode pmemX, + or 'sectored' mode. Select Y if unsure -- cgit v1.2.3