This patch adds 'DAXDEV_SYNC' flag which is set for nd_region doing synchronous flush. This later is used to disable MAP_SYNC functionality for ext4 & xfs filesystem for devices don't support synchronous flush.
Signed-off-by: Pankaj Gupta <pagu...@redhat.com> --- drivers/dax/bus.c | 2 +- drivers/dax/super.c | 19 ++++++++++++++++++- drivers/md/dm.c | 3 ++- drivers/nvdimm/pmem.c | 5 ++++- drivers/nvdimm/region_devs.c | 7 +++++++ include/linux/dax.h | 9 +++++++-- include/linux/libnvdimm.h | 1 + 7 files changed, 40 insertions(+), 6 deletions(-) diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c index 2109cfe80219..5f184e751c82 100644 --- a/drivers/dax/bus.c +++ b/drivers/dax/bus.c @@ -388,7 +388,7 @@ struct dev_dax *__devm_create_dev_dax(struct dax_region *dax_region, int id, * No 'host' or dax_operations since there is no access to this * device outside of mmap of the resulting character device. */ - dax_dev = alloc_dax(dev_dax, NULL, NULL); + dax_dev = alloc_dax(dev_dax, NULL, NULL, DAXDEV_F_SYNC); if (!dax_dev) goto err; diff --git a/drivers/dax/super.c b/drivers/dax/super.c index bbd57ca0634a..93b3718b5cfa 100644 --- a/drivers/dax/super.c +++ b/drivers/dax/super.c @@ -186,6 +186,8 @@ enum dax_device_flags { DAXDEV_ALIVE, /* gate whether dax_flush() calls the low level flush routine */ DAXDEV_WRITE_CACHE, + /* flag to check if device supports synchronous flush */ + DAXDEV_SYNC, }; /** @@ -354,6 +356,18 @@ bool dax_write_cache_enabled(struct dax_device *dax_dev) } EXPORT_SYMBOL_GPL(dax_write_cache_enabled); +bool dax_synchronous(struct dax_device *dax_dev) +{ + return test_bit(DAXDEV_SYNC, &dax_dev->flags); +} +EXPORT_SYMBOL_GPL(dax_synchronous); + +void set_dax_synchronous(struct dax_device *dax_dev) +{ + set_bit(DAXDEV_SYNC, &dax_dev->flags); +} +EXPORT_SYMBOL_GPL(set_dax_synchronous); + bool dax_alive(struct dax_device *dax_dev) { lockdep_assert_held(&dax_srcu); @@ -508,7 +522,7 @@ static void dax_add_host(struct dax_device *dax_dev, const char *host) } struct dax_device *alloc_dax(void *private, const char *__host, - const struct dax_operations *ops) + const struct dax_operations *ops, unsigned long flags) { struct dax_device *dax_dev; const char *host; @@ -531,6 +545,9 @@ struct dax_device *alloc_dax(void *private, const char *__host, dax_add_host(dax_dev, host); dax_dev->ops = ops; dax_dev->private = private; + if (flags & DAXDEV_F_SYNC) + set_dax_synchronous(dax_dev); + return dax_dev; err_dev: diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 1fb1333fefec..7eee7ddc73a8 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1970,7 +1970,8 @@ static struct mapped_device *alloc_dev(int minor) sprintf(md->disk->disk_name, "dm-%d", minor); if (IS_ENABLED(CONFIG_DAX_DRIVER)) { - md->dax_dev = alloc_dax(md, md->disk->disk_name, &dm_dax_ops); + md->dax_dev = alloc_dax(md, md->disk->disk_name, + &dm_dax_ops, 0); if (!md->dax_dev) goto bad; } diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 0279eb1da3ef..bdbd2b414d3d 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -365,6 +365,7 @@ static int pmem_attach_disk(struct device *dev, struct gendisk *disk; void *addr; int rc; + unsigned long flags = 0UL; pmem = devm_kzalloc(dev, sizeof(*pmem), GFP_KERNEL); if (!pmem) @@ -462,7 +463,9 @@ static int pmem_attach_disk(struct device *dev, nvdimm_badblocks_populate(nd_region, &pmem->bb, &bb_res); disk->bb = &pmem->bb; - dax_dev = alloc_dax(pmem, disk->disk_name, &pmem_dax_ops); + if (is_nvdimm_sync(nd_region)) + flags = DAXDEV_F_SYNC; + dax_dev = alloc_dax(pmem, disk->disk_name, &pmem_dax_ops, flags); if (!dax_dev) { put_disk(disk); return -ENOMEM; diff --git a/drivers/nvdimm/region_devs.c b/drivers/nvdimm/region_devs.c index b4ef7d9ff22e..f3ea5369d20a 100644 --- a/drivers/nvdimm/region_devs.c +++ b/drivers/nvdimm/region_devs.c @@ -1197,6 +1197,13 @@ int nvdimm_has_cache(struct nd_region *nd_region) } EXPORT_SYMBOL_GPL(nvdimm_has_cache); +bool is_nvdimm_sync(struct nd_region *nd_region) +{ + return is_nd_pmem(&nd_region->dev) && + !test_bit(ND_REGION_ASYNC, &nd_region->flags); +} +EXPORT_SYMBOL_GPL(is_nvdimm_sync); + struct conflict_context { struct nd_region *nd_region; resource_size_t start, size; diff --git a/include/linux/dax.h b/include/linux/dax.h index 0dd316a74a29..2b106752b1b8 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -7,6 +7,9 @@ #include <linux/radix-tree.h> #include <asm/pgtable.h> +/* Flag for synchronous flush */ +#define DAXDEV_F_SYNC (1UL << 0) + typedef unsigned long dax_entry_t; struct iomap_ops; @@ -32,18 +35,20 @@ extern struct attribute_group dax_attribute_group; #if IS_ENABLED(CONFIG_DAX) struct dax_device *dax_get_by_host(const char *host); struct dax_device *alloc_dax(void *private, const char *host, - const struct dax_operations *ops); + const struct dax_operations *ops, unsigned long flags); void put_dax(struct dax_device *dax_dev); void kill_dax(struct dax_device *dax_dev); void dax_write_cache(struct dax_device *dax_dev, bool wc); bool dax_write_cache_enabled(struct dax_device *dax_dev); +bool dax_synchronous(struct dax_device *dax_dev); +void set_dax_synchronous(struct dax_device *dax_dev); #else static inline struct dax_device *dax_get_by_host(const char *host) { return NULL; } static inline struct dax_device *alloc_dax(void *private, const char *host, - const struct dax_operations *ops) + const struct dax_operations *ops, unsigned long flags) { /* * Callers should check IS_ENABLED(CONFIG_DAX) to know if this diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h index feb342d026f2..3238a206e563 100644 --- a/include/linux/libnvdimm.h +++ b/include/linux/libnvdimm.h @@ -264,6 +264,7 @@ void nvdimm_flush(struct nd_region *nd_region); int nvdimm_has_flush(struct nd_region *nd_region); int nvdimm_has_cache(struct nd_region *nd_region); int nvdimm_in_overwrite(struct nvdimm *nvdimm); +bool is_nvdimm_sync(struct nd_region *nd_region); static inline int nvdimm_ctl(struct nvdimm *nvdimm, unsigned int cmd, void *buf, unsigned int buf_len, int *cmd_rc) -- 2.20.1 _______________________________________________ Linux-nvdimm mailing list Linux-nvdimm@lists.01.org https://lists.01.org/mailman/listinfo/linux-nvdimm