From 6ff3e912d32ece4e9cf8708da796e9e2e7979ffe Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Wed, 5 Oct 2016 14:04:15 -0700 Subject: [PATCH] libnvdimm, namespace: sort namespaces by dpa at init Add more determinism to initial namespace device-name assignments by sorting the namespaces by starting dpa. Signed-off-by: Dan Williams --- drivers/nvdimm/namespace_devs.c | 35 ++++++++++++++++++++++++++++++--- include/linux/nd.h | 6 +++--- 2 files changed, 35 insertions(+), 6 deletions(-) diff --git a/drivers/nvdimm/namespace_devs.c b/drivers/nvdimm/namespace_devs.c index 47d29632b937..f0536c2789e9 100644 --- a/drivers/nvdimm/namespace_devs.c +++ b/drivers/nvdimm/namespace_devs.c @@ -12,6 +12,7 @@ */ #include #include +#include #include #include #include @@ -66,17 +67,17 @@ static struct device_type namespace_blk_device_type = { .release = namespace_blk_release, }; -static bool is_namespace_pmem(struct device *dev) +static bool is_namespace_pmem(const struct device *dev) { return dev ? dev->type == &namespace_pmem_device_type : false; } -static bool is_namespace_blk(struct device *dev) +static bool is_namespace_blk(const struct device *dev) { return dev ? dev->type == &namespace_blk_device_type : false; } -static bool is_namespace_io(struct device *dev) +static bool is_namespace_io(const struct device *dev) { return dev ? dev->type == &namespace_io_device_type : false; } @@ -1919,6 +1920,31 @@ struct device *create_namespace_blk(struct nd_region *nd_region, return ERR_PTR(-ENXIO); } +static int cmp_dpa(const void *a, const void *b) +{ + const struct device *dev_a = *(const struct device **) a; + const struct device *dev_b = *(const struct device **) b; + struct nd_namespace_blk *nsblk_a, *nsblk_b; + struct nd_namespace_pmem *nspm_a, *nspm_b; + + if (is_namespace_io(dev_a)) + return 0; + + if (is_namespace_blk(dev_a)) { + nsblk_a = to_nd_namespace_blk(dev_a); + nsblk_b = to_nd_namespace_blk(dev_b); + + return memcmp(&nsblk_a->res[0]->start, &nsblk_b->res[0]->start, + sizeof(resource_size_t)); + } + + nspm_a = to_nd_namespace_pmem(dev_a); + nspm_b = to_nd_namespace_pmem(dev_b); + + return memcmp(&nspm_a->nsio.res.start, &nspm_b->nsio.res.start, + sizeof(resource_size_t)); +} + static struct device **scan_labels(struct nd_region *nd_region) { struct nd_mapping *nd_mapping = &nd_region->mapping[0]; @@ -2034,6 +2060,9 @@ static struct device **scan_labels(struct nd_region *nd_region) } } + if (count > 1) + sort(devs, count, sizeof(struct device *), cmp_dpa, NULL); + return devs; err: diff --git a/include/linux/nd.h b/include/linux/nd.h index ddcc7788305c..fa66aeed441a 100644 --- a/include/linux/nd.h +++ b/include/linux/nd.h @@ -107,19 +107,19 @@ struct nd_namespace_blk { struct resource **res; }; -static inline struct nd_namespace_io *to_nd_namespace_io(struct device *dev) +static inline struct nd_namespace_io *to_nd_namespace_io(const struct device *dev) { return container_of(dev, struct nd_namespace_io, common.dev); } -static inline struct nd_namespace_pmem *to_nd_namespace_pmem(struct device *dev) +static inline struct nd_namespace_pmem *to_nd_namespace_pmem(const struct device *dev) { struct nd_namespace_io *nsio = to_nd_namespace_io(dev); return container_of(nsio, struct nd_namespace_pmem, nsio); } -static inline struct nd_namespace_blk *to_nd_namespace_blk(struct device *dev) +static inline struct nd_namespace_blk *to_nd_namespace_blk(const struct device *dev) { return container_of(dev, struct nd_namespace_blk, common.dev); } -- 2.20.1