diff options
| author | Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> | 2018-06-20 00:01:41 -0400 |
|---|---|---|
| committer | Christoph Hellwig <hch@lst.de> | 2018-07-23 09:35:14 +0200 |
| commit | 55eb942eda2ccbbbea61db4c1a774ba22b618046 (patch) | |
| tree | cfeeeaadeaf87b88e73a6bdf2ec878fc846b8b11 /drivers/nvme/target/configfs.c | |
| parent | 0866bf0c3778661e65f68a5c93df8e0a1e9e43cc (diff) | |
nvmet: add buffered I/O support for file backed ns
Add a new "buffered_io" attribute, which disabled direct I/O and thus
enables page cache based caching when enabled. The attribute can only
be changed when the namespace is disabled as the file has to be reopend
for the change to take effect.
The possibly blocking read/write are deferred to a newly introduced
global workqueue.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Diffstat (limited to 'drivers/nvme/target/configfs.c')
| -rw-r--r-- | drivers/nvme/target/configfs.c | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/drivers/nvme/target/configfs.c b/drivers/nvme/target/configfs.c index d3f3b3ec4d1a..fee56b3a23bc 100644 --- a/drivers/nvme/target/configfs.c +++ b/drivers/nvme/target/configfs.c @@ -407,11 +407,40 @@ static ssize_t nvmet_ns_enable_store(struct config_item *item, CONFIGFS_ATTR(nvmet_ns_, enable); +static ssize_t nvmet_ns_buffered_io_show(struct config_item *item, char *page) +{ + return sprintf(page, "%d\n", to_nvmet_ns(item)->buffered_io); +} + +static ssize_t nvmet_ns_buffered_io_store(struct config_item *item, + const char *page, size_t count) +{ + struct nvmet_ns *ns = to_nvmet_ns(item); + bool val; + + if (strtobool(page, &val)) + return -EINVAL; + + mutex_lock(&ns->subsys->lock); + if (ns->enabled) { + pr_err("disable ns before setting buffered_io value.\n"); + mutex_unlock(&ns->subsys->lock); + return -EINVAL; + } + + ns->buffered_io = val; + mutex_unlock(&ns->subsys->lock); + return count; +} + +CONFIGFS_ATTR(nvmet_ns_, buffered_io); + static struct configfs_attribute *nvmet_ns_attrs[] = { &nvmet_ns_attr_device_path, &nvmet_ns_attr_device_nguid, &nvmet_ns_attr_device_uuid, &nvmet_ns_attr_enable, + &nvmet_ns_attr_buffered_io, NULL, }; |