Grab a reference on a network namespace of the 'rbd map' (in case of
rbd) or 'mount' (in case of ceph) process and use that to open sockets
instead of always using init_net and bailing if network namespace is
anything but init_net.  Be careful to not share struct ceph_client
instances between different namespaces and don't add any code in the
!CONFIG_NET_NS case.

This is based on a patch from Hong Zhiguo <zhiguohong@tencent.com>.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Sage Weil <sage@redhat.com>

modinfo libceph prints the module name "Ceph filesystem for Linux",
which is same as the real fs module ceph. It's confusing.

Signed-off-by: Hong Zhiguo <zhiguohong@tencent.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

- return -ETIMEDOUT instead of -EIO in case of timeout
- wait_event_interruptible_timeout() returns time left until timeout
  and since it can be almost LONG_MAX we had better assign it to long

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Alex Elder <elder@linaro.org>

There are currently three libceph-level timeouts that the user can
specify on mount: mount_timeout, osd_idle_ttl and osdkeepalive.  All of
these are in seconds and no checking is done on user input: negative
values are accepted, we multiply them all by HZ which may or may not
overflow, arbitrarily large jiffies then get added together, etc.

There is also a bug in the way mount_timeout=0 is handled.  It's
supposed to mean "infinite timeout", but that's not how wait.h APIs
treat it and so __ceph_open_session() for example will busy loop
without much chance of being interrupted if none of ceph-mons are
there.

Fix all this by verifying user input, storing timeouts capped by
msecs_to_jiffies() in jiffies and using the new ceph_timeout_jiffies()
helper for all user-specified waits to handle infinite timeouts
correctly.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Alex Elder <elder@linaro.org>

Split ceph_show_options() into two pieces and move the piece
responsible for printing client (libceph) options into net/ceph.  This
way people adding a libceph option wouldn't have to remember to update
code in fs/ceph.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

TCP_NODELAY socket option set on connection sockets,
disables Nagle’s algorithm and improves latency characteristics.
tcp_nodelay(default)/notcp_nodelay option flags provided to
enable/disable setting the socket option.

Signed-off-by: Chaitanya Huilgol <chaitanya.huilgol@sandisk.com>
[idryomov@redhat.com: NO_TCP_NODELAY -> TCP_NODELAY, minor adjustments]
Signed-off-by: Ilya Dryomov <idryomov@redhat.com>

Signed-off-by: Yan, Zheng <zyan@redhat.com>
Reviewed-by: Ilya Dryomov <idryomov@redhat.com>

Use kvfree() from linux/mm.h instead, which is identical.  Also fix the
ceph_buffer comment: we will allocate with kmalloc() up to 32k - the
value of PAGE_ALLOC_COSTLY_ORDER, but that really is just an
implementation detail so don't mention it at all.

Signed-off-by: Ilya Dryomov <idryomov@redhat.com>

Use the more common pr_warn.

Other miscellanea:

o Coalesce formats
o Realign arguments

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>

Add support for mon_get_version requests to libceph.  This reuses much
of the ceph_mon_generic_request infrastructure, with one exception.
Older OSDs don't set mon_get_version reply hdr->tid even if the
original request had a non-zero tid, which makes it impossible to
lookup ceph_mon_generic_request contexts by tid in get_generic_reply()
for such replies.  As a workaround, we allocate a reply message on the
reply path.  This can probably interfere with revoke, but I don't see
a better way.

Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>