[PATCH v3 09/21] libnd, nd_pmem: add libnd support to the pmem driver
From: Dan Williams
Date: Wed May 20 2015 - 17:04:30 EST
nd_pmem attaches to persistent memory regions and namespaces emitted by
the libnd subsystem, and, same as the original pmem driver, presents the
system-physical-address range as a block device.
The existing e820-type-12 to pmem setup is converted to a full libnd bus
that emits an nd_namespace_io device.
Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
Cc: Boaz Harrosh <boaz@xxxxxxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Jens Axboe <axboe@xxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
arch/x86/kernel/pmem.c | 2 -
drivers/block/Kconfig | 19 ++++-----
drivers/block/Makefile | 2 -
drivers/block/e820_pmem.c | 100 +++++++++++++++++++++++++++++++++++++++++++++
drivers/block/nd/Kconfig | 17 ++++++++
drivers/block/nd/Makefile | 3 +
drivers/block/nd/pmem.c | 60 +++++++++++++--------------
7 files changed, 159 insertions(+), 44 deletions(-)
create mode 100644 drivers/block/e820_pmem.c
rename drivers/block/{pmem.c => nd/pmem.c} (85%)
diff --git a/arch/x86/kernel/pmem.c b/arch/x86/kernel/pmem.c
index 3420c874ddc5..279328c42f87 100644
--- a/arch/x86/kernel/pmem.c
+++ b/arch/x86/kernel/pmem.c
@@ -13,7 +13,7 @@ static __init void register_pmem_device(struct resource *res)
struct platform_device *pdev;
int error;
- pdev = platform_device_alloc("pmem", PLATFORM_DEVID_AUTO);
+ pdev = platform_device_alloc("e820_pmem", PLATFORM_DEVID_AUTO);
if (!pdev)
return;
diff --git a/drivers/block/Kconfig b/drivers/block/Kconfig
index dfe40e5ca9bd..4c2cfb91755f 100644
--- a/drivers/block/Kconfig
+++ b/drivers/block/Kconfig
@@ -323,6 +323,14 @@ config BLK_DEV_NVME
source "drivers/block/nd/Kconfig"
+config E820_PMEM
+ tristate "E820 defined Persistent Memory (legacy)"
+ depends on PHYS_ADDR_T_64BIT
+ depends on X86_PMEM_LEGACY
+ default m if X86_PMEM_LEGACY
+ select ND_DEVICES
+ select LIBND
+
config BLK_DEV_SKD
tristate "STEC S1120 Block Driver"
depends on PCI
@@ -406,17 +414,6 @@ config BLK_DEV_RAM_DAX
and will prevent RAM block device backing store memory from being
allocated from highmem (only a problem for highmem systems).
-config BLK_DEV_PMEM
- tristate "Persistent memory block device support"
- help
- Saying Y here will allow you to use a contiguous range of reserved
- memory as one or more persistent block devices.
-
- To compile this driver as a module, choose M here: the module will be
- called 'pmem'.
-
- If unsure, say N.
-
config CDROM_PKTCDVD
tristate "Packet writing on CD/DVD media"
depends on !UML
diff --git a/drivers/block/Makefile b/drivers/block/Makefile
index 07a6acecf4d8..4cd5f8a919d8 100644
--- a/drivers/block/Makefile
+++ b/drivers/block/Makefile
@@ -14,7 +14,6 @@ obj-$(CONFIG_PS3_VRAM) += ps3vram.o
obj-$(CONFIG_ATARI_FLOPPY) += ataflop.o
obj-$(CONFIG_AMIGA_Z2RAM) += z2ram.o
obj-$(CONFIG_BLK_DEV_RAM) += brd.o
-obj-$(CONFIG_BLK_DEV_PMEM) += pmem.o
obj-$(CONFIG_BLK_DEV_LOOP) += loop.o
obj-$(CONFIG_BLK_CPQ_DA) += cpqarray.o
obj-$(CONFIG_BLK_CPQ_CISS_DA) += cciss.o
@@ -25,6 +24,7 @@ obj-$(CONFIG_MG_DISK) += mg_disk.o
obj-$(CONFIG_SUNVDC) += sunvdc.o
obj-$(CONFIG_BLK_DEV_NVME) += nvme.o
obj-$(CONFIG_ND_DEVICES) += nd/
+obj-$(CONFIG_E820_PMEM) += e820_pmem.o
obj-$(CONFIG_BLK_DEV_SKD) += skd.o
obj-$(CONFIG_BLK_DEV_OSD) += osdblk.o
diff --git a/drivers/block/e820_pmem.c b/drivers/block/e820_pmem.c
new file mode 100644
index 000000000000..48c33e43f39e
--- /dev/null
+++ b/drivers/block/e820_pmem.c
@@ -0,0 +1,100 @@
+/*
+ * libnd e820 support
+ *
+ * Copyright (c) 2014-2015, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.
+ */
+#include <linux/platform_device.h>
+#include <linux/module.h>
+#include <linux/libnd.h>
+
+static const struct attribute_group *e820_pmem_attribute_groups[] = {
+ &nd_bus_attribute_group,
+ NULL,
+};
+
+static const struct attribute_group *e820_pmem_region_attribute_groups[] = {
+ &nd_region_attribute_group,
+ &nd_device_attribute_group,
+ NULL,
+};
+
+static int e820_pmem_probe(struct platform_device *pdev)
+{
+ struct nd_bus_descriptor *nd_desc;
+ struct nd_region_desc ndr_desc;
+ struct nd_bus *nd_bus;
+ struct resource *res;
+
+ if (WARN_ON(pdev->num_resources > 1))
+ return -ENXIO;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -ENXIO;
+
+ nd_desc = devm_kzalloc(&pdev->dev, sizeof(*nd_desc), GFP_KERNEL);
+ if (!nd_desc)
+ return -ENOMEM;
+
+ nd_desc->attr_groups = e820_pmem_attribute_groups;
+ nd_desc->provider_name = "e820";
+ nd_bus = nd_bus_register(&pdev->dev, nd_desc);
+ if (!nd_bus)
+ return -ENXIO;
+
+ memset(&ndr_desc, 0, sizeof(ndr_desc));
+ ndr_desc.res = res;
+ ndr_desc.attr_groups = e820_pmem_region_attribute_groups;
+ if (!nd_pmem_region_create(nd_bus, &ndr_desc)) {
+ nd_bus_unregister(nd_bus);
+ return -ENXIO;
+ }
+
+ platform_set_drvdata(pdev, nd_bus);
+
+ return 0;
+}
+
+static int e820_pmem_remove(struct platform_device *pdev)
+{
+ struct nd_bus *nd_bus = platform_get_drvdata(pdev);
+
+ nd_bus_unregister(nd_bus);
+
+ return 0;
+}
+
+static struct platform_driver e820_pmem_driver = {
+ .probe = e820_pmem_probe,
+ .remove = e820_pmem_remove,
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "e820_pmem",
+ },
+};
+
+MODULE_ALIAS("platform:e820_pmem*");
+
+static int __init e820_pmem_init(void)
+{
+ return platform_driver_register(&e820_pmem_driver);
+}
+module_init(e820_pmem_init);
+
+static void e820_pmem_exit(void)
+{
+ platform_driver_unregister(&e820_pmem_driver);
+}
+module_exit(e820_pmem_exit);
+
+MODULE_AUTHOR("Intel Corporation");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/block/nd/Kconfig b/drivers/block/nd/Kconfig
index 9b909c21afa1..03f572f0e3d0 100644
--- a/drivers/block/nd/Kconfig
+++ b/drivers/block/nd/Kconfig
@@ -17,4 +17,21 @@ if ND_DEVICES
config LIBND
tristate
+config BLK_DEV_PMEM
+ tristate "PMEM: Persistent memory block device support"
+ depends on LIBND
+ default LIBND
+ help
+ Memory ranges for PMEM are described by either an NFIT
+ (NVDIMM Firmware Interface Table, see CONFIG_NFIT_ACPI), a
+ non-standard OEM-specific E820 memory type (type-12, see
+ CONFIG_X86_PMEM_LEGACY), or it is manually specified by the
+ 'memmap=nn[KMG]!ss[KMG]' kernel command line (see
+ Documentation/kernel-parameters.txt). This driver converts
+ these persistent memory ranges into block devices that are
+ capable of DAX (direct-access) file system mappings. See
+ Documentation/blockdev/nd.txt for more details.
+
+ Say Y if you want to use a NVDIMM described by NFIT
+
endif
diff --git a/drivers/block/nd/Makefile b/drivers/block/nd/Makefile
index 235d9e6be94a..6f539f01fa82 100644
--- a/drivers/block/nd/Makefile
+++ b/drivers/block/nd/Makefile
@@ -1,4 +1,7 @@
obj-$(CONFIG_LIBND) += libnd.o
+obj-$(CONFIG_BLK_DEV_PMEM) += nd_pmem.o
+
+nd_pmem-y := pmem.o
libnd-y := core.o
libnd-y += bus.o
diff --git a/drivers/block/pmem.c b/drivers/block/nd/pmem.c
similarity index 85%
rename from drivers/block/pmem.c
rename to drivers/block/nd/pmem.c
index eabf4a8d0085..529a1444a918 100644
--- a/drivers/block/pmem.c
+++ b/drivers/block/nd/pmem.c
@@ -1,7 +1,7 @@
/*
* Persistent Memory Driver
*
- * Copyright (c) 2014, Intel Corporation.
+ * Copyright (c) 2014-2015, Intel Corporation.
* Copyright (c) 2015, Christoph Hellwig <hch@xxxxxx>.
* Copyright (c) 2015, Boaz Harrosh <boaz@xxxxxxxxxxxxx>.
*
@@ -23,6 +23,8 @@
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/slab.h>
+#include <linux/nd.h>
+#include "nd.h"
#define PMEM_MINORS 16
@@ -37,7 +39,6 @@ struct pmem_device {
};
static int pmem_major;
-static atomic_t pmem_index;
static void pmem_do_bvec(struct pmem_device *pmem, struct page *page,
unsigned int len, unsigned int off, int rw,
@@ -118,11 +119,11 @@ static const struct block_device_operations pmem_fops = {
.direct_access = pmem_direct_access,
};
-static struct pmem_device *pmem_alloc(struct device *dev, struct resource *res)
+static struct pmem_device *pmem_alloc(struct device *dev, struct resource *res, int id)
{
struct pmem_device *pmem;
struct gendisk *disk;
- int idx, err;
+ int err;
err = -ENOMEM;
pmem = kzalloc(sizeof(*pmem), GFP_KERNEL);
@@ -159,15 +160,13 @@ static struct pmem_device *pmem_alloc(struct device *dev, struct resource *res)
if (!disk)
goto out_free_queue;
- idx = atomic_inc_return(&pmem_index) - 1;
-
disk->major = pmem_major;
- disk->first_minor = PMEM_MINORS * idx;
+ disk->first_minor = PMEM_MINORS * id;
disk->fops = &pmem_fops;
disk->private_data = pmem;
disk->queue = pmem->pmem_queue;
disk->flags = GENHD_FL_EXT_DEVT;
- sprintf(disk->disk_name, "pmem%d", idx);
+ sprintf(disk->disk_name, "pmem%d", id);
disk->driverfs_dev = dev;
set_capacity(disk, pmem->size >> 9);
pmem->pmem_disk = disk;
@@ -198,42 +197,38 @@ static void pmem_free(struct pmem_device *pmem)
kfree(pmem);
}
-static int pmem_probe(struct platform_device *pdev)
+static int nd_pmem_probe(struct device *dev)
{
+ struct nd_region *nd_region = to_nd_region(dev->parent);
+ struct nd_namespace_io *nsio = to_nd_namespace_io(dev);
struct pmem_device *pmem;
- struct resource *res;
-
- if (WARN_ON(pdev->num_resources > 1))
- return -ENXIO;
-
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (!res)
- return -ENXIO;
- pmem = pmem_alloc(&pdev->dev, res);
+ pmem = pmem_alloc(dev, &nsio->res, nd_region->id);
if (IS_ERR(pmem))
return PTR_ERR(pmem);
- platform_set_drvdata(pdev, pmem);
+ dev_set_drvdata(dev, pmem);
return 0;
}
-static int pmem_remove(struct platform_device *pdev)
+static int nd_pmem_remove(struct device *dev)
{
- struct pmem_device *pmem = platform_get_drvdata(pdev);
+ struct pmem_device *pmem = dev_get_drvdata(dev);
pmem_free(pmem);
return 0;
}
-static struct platform_driver pmem_driver = {
- .probe = pmem_probe,
- .remove = pmem_remove,
- .driver = {
- .owner = THIS_MODULE,
- .name = "pmem",
+MODULE_ALIAS("pmem");
+MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_IO);
+static struct nd_device_driver nd_pmem_driver = {
+ .probe = nd_pmem_probe,
+ .remove = nd_pmem_remove,
+ .drv = {
+ .name = "pmem",
},
+ .type = ND_DRIVER_NAMESPACE_IO,
};
static int __init pmem_init(void)
@@ -244,16 +239,19 @@ static int __init pmem_init(void)
if (pmem_major < 0)
return pmem_major;
- error = platform_driver_register(&pmem_driver);
- if (error)
+ error = nd_driver_register(&nd_pmem_driver);
+ if (error) {
unregister_blkdev(pmem_major, "pmem");
- return error;
+ return error;
+ }
+
+ return 0;
}
module_init(pmem_init);
static void pmem_exit(void)
{
- platform_driver_unregister(&pmem_driver);
+ driver_unregister(&nd_pmem_driver.drv);
unregister_blkdev(pmem_major, "pmem");
}
module_exit(pmem_exit);
--
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