Add an interface to retrieve the 'resource' attribute for a dax device. Attempt to retrieve it as usual via sysfs, but since older kernels may be missing this attribute, as a fallback, attempt to retrieve it from /proc/iomem
Cc: Dan Williams <[email protected]> [fscanf format string problem and diagnosis] Reported-by: Tony Luck <[email protected]> Signed-off-by: Vishal Verma <[email protected]> --- Makefile.am | 3 ++- daxctl/lib/Makefile.am | 2 ++ daxctl/lib/libdaxctl-private.h | 1 + daxctl/lib/libdaxctl.c | 12 +++++++++++ daxctl/lib/libdaxctl.sym | 1 + daxctl/libdaxctl.h | 1 + util/iomem.c | 37 ++++++++++++++++++++++++++++++++++ util/iomem.h | 12 +++++++++++ 8 files changed, 68 insertions(+), 1 deletion(-) create mode 100644 util/iomem.c create mode 100644 util/iomem.h diff --git a/Makefile.am b/Makefile.am index df8797e..8d10a10 100644 --- a/Makefile.am +++ b/Makefile.am @@ -74,6 +74,7 @@ libutil_a_SOURCES = \ util/wrapper.c \ util/filter.c \ util/bitmap.c \ - util/abspath.c + util/abspath.c \ + util/iomem.c nobase_include_HEADERS = daxctl/libdaxctl.h diff --git a/daxctl/lib/Makefile.am b/daxctl/lib/Makefile.am index 9f0e444..7704b1b 100644 --- a/daxctl/lib/Makefile.am +++ b/daxctl/lib/Makefile.am @@ -9,6 +9,8 @@ lib_LTLIBRARIES = libdaxctl.la libdaxctl_la_SOURCES =\ ../libdaxctl.h \ libdaxctl-private.h \ + ../../util/iomem.c \ + ../../util/iomem.h \ ../../util/sysfs.c \ ../../util/sysfs.h \ ../../util/log.c \ diff --git a/daxctl/lib/libdaxctl-private.h b/daxctl/lib/libdaxctl-private.h index e64d0a7..eb7c1ec 100644 --- a/daxctl/lib/libdaxctl-private.h +++ b/daxctl/lib/libdaxctl-private.h @@ -59,6 +59,7 @@ struct daxctl_dev { size_t buf_len; char *dev_path; struct list_node list; + unsigned long long resource; unsigned long long size; struct kmod_module *module; struct kmod_list *kmod_list; diff --git a/daxctl/lib/libdaxctl.c b/daxctl/lib/libdaxctl.c index 05f013b..5431063 100644 --- a/daxctl/lib/libdaxctl.c +++ b/daxctl/lib/libdaxctl.c @@ -24,6 +24,7 @@ #include <util/log.h> #include <util/sysfs.h> +#include <util/iomem.h> #include <daxctl/libdaxctl.h> #include "libdaxctl-private.h" @@ -369,6 +370,12 @@ static void *add_dax_dev(void *parent, int id, const char *daxdev_base) dev->major = major(st.st_rdev); dev->minor = minor(st.st_rdev); + sprintf(path, "%s/resource", daxdev_base); + if (sysfs_read_attr(ctx, path, buf) == 0) + dev->resource = strtoull(buf, NULL, 0); + else + dev->resource = iomem_get_dev_resource(ctx, daxdev_base); + sprintf(path, "%s/size", daxdev_base); if (sysfs_read_attr(ctx, path, buf) < 0) goto err_read; @@ -878,6 +885,11 @@ DAXCTL_EXPORT int daxctl_dev_get_minor(struct daxctl_dev *dev) return dev->minor; } +DAXCTL_EXPORT unsigned long long daxctl_dev_get_resource(struct daxctl_dev *dev) +{ + return dev->resource; +} + DAXCTL_EXPORT unsigned long long daxctl_dev_get_size(struct daxctl_dev *dev) { return dev->size; diff --git a/daxctl/lib/libdaxctl.sym b/daxctl/lib/libdaxctl.sym index 19904a2..1692624 100644 --- a/daxctl/lib/libdaxctl.sym +++ b/daxctl/lib/libdaxctl.sym @@ -58,4 +58,5 @@ global: daxctl_dev_disable; daxctl_dev_enable_devdax; daxctl_dev_enable_ram; + daxctl_dev_get_resource; } LIBDAXCTL_5; diff --git a/daxctl/libdaxctl.h b/daxctl/libdaxctl.h index b80488e..7214cd3 100644 --- a/daxctl/libdaxctl.h +++ b/daxctl/libdaxctl.h @@ -66,6 +66,7 @@ int daxctl_dev_get_id(struct daxctl_dev *dev); const char *daxctl_dev_get_devname(struct daxctl_dev *dev); int daxctl_dev_get_major(struct daxctl_dev *dev); int daxctl_dev_get_minor(struct daxctl_dev *dev); +unsigned long long daxctl_dev_get_resource(struct daxctl_dev *dev); unsigned long long daxctl_dev_get_size(struct daxctl_dev *dev); struct daxctl_ctx *daxctl_dev_get_ctx(struct daxctl_dev *dev); int daxctl_dev_is_enabled(struct daxctl_dev *dev); diff --git a/util/iomem.c b/util/iomem.c new file mode 100644 index 0000000..a3c23f5 --- /dev/null +++ b/util/iomem.c @@ -0,0 +1,37 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* Copyright(c) 2019 Intel Corporation. All rights reserved. */ + +#include <stdio.h> +#include <errno.h> +#include <string.h> +#include <util/log.h> +#include <util/iomem.h> +#include <util/sysfs.h> + +unsigned long long __iomem_get_dev_resource(struct log_ctx *ctx, + const char *devpath) +{ + const char *devname = devpath_to_devname(devpath); + FILE *fp = fopen("/proc/iomem", "r"); + unsigned long long res; + char name[256]; + + if (fp == NULL) { + log_err(ctx, "%s: open /proc/iomem: %s\n", devname, + strerror(errno)); + return 0; + } + + while (fscanf(fp, "%llx-%*x : %254[^\n]\n", &res, name) == 2) { + if (strcmp(name, devname) == 0) { + log_dbg(ctx, "%s: got resource via iomem: %#llx\n", + devname, res); + fclose(fp); + return res; + } + } + + log_dbg(ctx, "%s: not found in iomem\n", devname); + fclose(fp); + return 0; +} diff --git a/util/iomem.h b/util/iomem.h new file mode 100644 index 0000000..aaaf6a7 --- /dev/null +++ b/util/iomem.h @@ -0,0 +1,12 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* Copyright(c) 2019 Intel Corporation. All rights reserved. */ +#ifndef _NDCTL_IOMEM_H_ +#define _NDCTL_IOMEM_H_ + +struct log_ctx; +unsigned long long __iomem_get_dev_resource(struct log_ctx *ctx, + const char *path); + +#define iomem_get_dev_resource(c, p) __iomem_get_dev_resource(&(c)->ctx, (p)) + +#endif /* _NDCTL_IOMEM_H_ */ -- 2.20.1 _______________________________________________ Linux-nvdimm mailing list [email protected] https://lists.01.org/mailman/listinfo/linux-nvdimm
