From 5faecf4eb0d7d67e809a4bc9059c764c27670832 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Wed, 17 Feb 2016 15:25:36 -0800 Subject: [PATCH] libnvdimm: protect nvdimm_{bus|namespace}_add_poison() with nvdimm_bus_lock() In preparation for making poison list retrieval asynchronus to region registration, add protection for walking and mutating the bus-level poison list. Cc: Vishal Verma Signed-off-by: Dan Williams --- drivers/nvdimm/core.c | 111 ++++++++++++++++++++++++++---------------- 1 file changed, 68 insertions(+), 43 deletions(-) diff --git a/drivers/nvdimm/core.c b/drivers/nvdimm/core.c index 2e2832b83c93..f309e6bf6833 100644 --- a/drivers/nvdimm/core.c +++ b/drivers/nvdimm/core.c @@ -408,6 +408,48 @@ static void __add_badblock_range(struct badblocks *bb, u64 ns_offset, u64 len) set_badblock(bb, start_sector, num_sectors); } +static void namespace_add_poison(struct list_head *poison_list, + struct badblocks *bb, struct resource *res) +{ + struct nd_poison *pl; + + if (list_empty(poison_list)) + return; + + list_for_each_entry(pl, poison_list, list) { + u64 pl_end = pl->start + pl->length - 1; + + /* Discard intervals with no intersection */ + if (pl_end < res->start) + continue; + if (pl->start > res->end) + continue; + /* Deal with any overlap after start of the namespace */ + if (pl->start >= res->start) { + u64 start = pl->start; + u64 len; + + if (pl_end <= res->end) + len = pl->length; + else + len = res->start + resource_size(res) + - pl->start; + __add_badblock_range(bb, start - res->start, len); + continue; + } + /* Deal with overlap for poison starting before the namespace */ + if (pl->start < res->start) { + u64 len; + + if (pl_end < res->end) + len = pl->start + pl->length - res->start; + else + len = resource_size(res); + __add_badblock_range(bb, 0, len); + } + } +} + /** * nvdimm_namespace_add_poison() - Convert a list of poison ranges to badblocks * @ndns: the namespace containing poison ranges @@ -426,53 +468,21 @@ void nvdimm_namespace_add_poison(struct nd_namespace_common *ndns, struct nd_region *nd_region = to_nd_region(ndns->dev.parent); struct nvdimm_bus *nvdimm_bus; struct list_head *poison_list; - u64 ns_start, ns_end, ns_size; - struct nd_poison *pl; - - ns_size = nvdimm_namespace_capacity(ndns) - offset; - ns_start = nsio->res.start + offset; - ns_end = nsio->res.end; + struct resource res = { + .start = nsio->res.start + offset, + .end = nsio->res.end, + }; nvdimm_bus = to_nvdimm_bus(nd_region->dev.parent); poison_list = &nvdimm_bus->poison_list; - if (list_empty(poison_list)) - return; - list_for_each_entry(pl, poison_list, list) { - u64 pl_end = pl->start + pl->length - 1; - - /* Discard intervals with no intersection */ - if (pl_end < ns_start) - continue; - if (pl->start > ns_end) - continue; - /* Deal with any overlap after start of the namespace */ - if (pl->start >= ns_start) { - u64 start = pl->start; - u64 len; - - if (pl_end <= ns_end) - len = pl->length; - else - len = ns_start + ns_size - pl->start; - __add_badblock_range(bb, start - ns_start, len); - continue; - } - /* Deal with overlap for poison starting before the namespace */ - if (pl->start < ns_start) { - u64 len; - - if (pl_end < ns_end) - len = pl->start + pl->length - ns_start; - else - len = ns_size; - __add_badblock_range(bb, 0, len); - } - } + nvdimm_bus_lock(&nvdimm_bus->dev); + namespace_add_poison(poison_list, bb, &res); + nvdimm_bus_unlock(&nvdimm_bus->dev); } EXPORT_SYMBOL_GPL(nvdimm_namespace_add_poison); -static int __add_poison(struct nvdimm_bus *nvdimm_bus, u64 addr, u64 length) +static int add_poison(struct nvdimm_bus *nvdimm_bus, u64 addr, u64 length) { struct nd_poison *pl; @@ -487,12 +497,12 @@ static int __add_poison(struct nvdimm_bus *nvdimm_bus, u64 addr, u64 length) return 0; } -int nvdimm_bus_add_poison(struct nvdimm_bus *nvdimm_bus, u64 addr, u64 length) +static int bus_add_poison(struct nvdimm_bus *nvdimm_bus, u64 addr, u64 length) { struct nd_poison *pl; if (list_empty(&nvdimm_bus->poison_list)) - return __add_poison(nvdimm_bus, addr, length); + return add_poison(nvdimm_bus, addr, length); /* * There is a chance this is a duplicate, check for those first. @@ -512,7 +522,18 @@ int nvdimm_bus_add_poison(struct nvdimm_bus *nvdimm_bus, u64 addr, u64 length) * as any overlapping ranges will get resolved when the list is consumed * and converted to badblocks */ - return __add_poison(nvdimm_bus, addr, length); + return add_poison(nvdimm_bus, addr, length); +} + +int nvdimm_bus_add_poison(struct nvdimm_bus *nvdimm_bus, u64 addr, u64 length) +{ + int rc; + + nvdimm_bus_lock(&nvdimm_bus->dev); + rc = bus_add_poison(nvdimm_bus, addr, length); + nvdimm_bus_unlock(&nvdimm_bus->dev); + + return rc; } EXPORT_SYMBOL_GPL(nvdimm_bus_add_poison); @@ -553,7 +574,11 @@ void nvdimm_bus_unregister(struct nvdimm_bus *nvdimm_bus) nd_synchronize(); device_for_each_child(&nvdimm_bus->dev, NULL, child_unregister); + + nvdimm_bus_lock(&nvdimm_bus->dev); free_poison_list(&nvdimm_bus->poison_list); + nvdimm_bus_unlock(&nvdimm_bus->dev); + nvdimm_bus_destroy_ndctl(nvdimm_bus); device_unregister(&nvdimm_bus->dev);