Change the name of prepare_connect_authorizer().  The next
patch is going to make this function no longer add anything to the
connection's out_kvec, so it will no longer fit the pattern of
the rest of the prepare_connect_*() functions.

In addition, pass the address of a variable that will hold the
authorization protocol to use.  Move the assignment of that to the
connection's out_connect structure into prepare_write_connect().
Signed-off-by: NAlex Elder <elder@inktank.com>
Reviewed-by: NSage Weil <sage@inktank.com>

Change prepare_connect_authorizer() so it returns a pointer (or
pointer-coded error).
Signed-off-by: NAlex Elder <elder@inktank.com>
Reviewed-by: NSage Weil <sage@inktank.com>

Rather than passing a bunch of arguments to be filled in with the
content of the ceph_auth_handshake buffer now returned by the
get_authorizer method, just use the returned information in the
caller, and drop the unnecessary arguments.
Signed-off-by: NAlex Elder <elder@inktank.com>
Reviewed-by: NSage Weil <sage@inktank.com>

Have the get_authorizer auth_client method return a ceph_auth
pointer rather than an integer, pointer-encoding any returned
error value.  This is to pave the way for making use of the
returned value in an upcoming patch.
Signed-off-by: NAlex Elder <elder@inktank.com>
Reviewed-by: NSage Weil <sage@inktank.com>

In prepare_connect_authorizer(), a connection's get_authorizer
method is called but ignores its return value.  This function can
return an error, so check for it and return it if that ever occurs.
Signed-off-by: NAlex Elder <elder@inktank.com>
Reviewed-by: NSage Weil <sage@inktank.com>

Change prepare_connect_authorizer() so it returns without dropping
the connection mutex if the connection has no get_authorizer method.

Use the symbolic CEPH_AUTH_UNKNOWN instead of 0 when assigning
authorization protocols.
Signed-off-by: NAlex Elder <elder@inktank.com>
Reviewed-by: NSage Weil <sage@inktank.com>

prepare_write_connect() can return an error, but only one of its
callers checks for it.  All the rest are in functions that already
return errors, so it should be fine to return the error if one
gets returned.
Signed-off-by: NAlex Elder <elder@inktank.com>
Reviewed-by: NSage Weil <sage@inktank.com>

prepare_write_connect() prepares a connect message, then sets
WRITE_PENDING on the connection.  Then *after* this, it calls
prepare_connect_authorizer(), which updates the content of the
connection buffer already queued for sending.  It's also possible it
will result in prepare_write_connect() returning -EAGAIN despite the
WRITE_PENDING big getting set.

Fix this by preparing the connect authorizer first, setting the
WRITE_PENDING bit only after that is done.

Partially addresses http://tracker.newdream.net/issues/2424Signed-off-by: NAlex Elder <elder@inktank.com>
Reviewed-by: NSage Weil <sage@inktank.com>

In all cases, the value passed as the msgr argument to
prepare_write_connect() is just con->msgr.  Just get the msgr
value from the ceph connection and drop the unneeded argument.

The only msgr passed to prepare_write_banner() is also therefore
just the one from con->msgr, so change that function to drop the
msgr argument as well.
Signed-off-by: NAlex Elder <elder@inktank.com>
Reviewed-by: NSage Weil <sage@inktank.com>

prepare_write_connect() has an argument indicating whether a banner
should be sent out before sending out a connection message.  It's
only ever set in one of its callers, so move the code that arranges
to send the banner into that caller and drop the "include_banner"
argument from prepare_write_connect().
Signed-off-by: NAlex Elder <elder@inktank.com>
Reviewed-by: NSage Weil <sage@inktank.com>

Reset a connection's kvec fields in the caller rather than in
prepare_write_connect().   This ends up repeating a few lines of
code but it's improving the separation between distinct operations
on the connection, which we can take advantage of later.
Signed-off-by: NAlex Elder <elder@inktank.com>
Reviewed-by: NSage Weil <sage@inktank.com>

Move the kvec reset for a connection out of prepare_write_banner and
into its only caller.
Signed-off-by: NAlex Elder <elder@inktank.com>
Reviewed-by: NSage Weil <sage@inktank.com>

Make the second argument to read_partial() be the ending input byte
position rather than the beginning offset it now represents.  This
amounts to moving the addition "to + size" into the caller.
Signed-off-by: NAlex Elder <elder@inktank.com>
Reviewed-by: NSage Weil <sage@inktank.com>

read_partial() always increases whatever "to" value is supplied by
adding the requested size to it, and that's the only thing it does
with that pointed-to value.

Do that pointer advance in the caller (and then only when the
updated value will be subsequently used), and change the "to"
parameter to be an in-only and non-pointer value.
Signed-off-by: NAlex Elder <elder@inktank.com>
Reviewed-by: NSage Weil <sage@inktank.com>

There are two blocks of code in read_partial_message()--those that
read the header and footer of the message--that can be replaced by a
call to read_partial().  Do that.
Signed-off-by: NAlex Elder <elder@inktank.com>
Reviewed-by: NSage Weil <sage@inktank.com>

In write_partial_msg_pages(), every case now does an identical call
to kmap(page).  Instead, just call it once inside the CRC-computing
block where it's needed.  Move the definition of kaddr inside that
block, and make it a (char *) to ensure portable pointer arithmetic.

We still don't kunmap() it until after the sendpage() call, in case
that also ends up needing to use the mapping.
Signed-off-by: NAlex Elder <elder@dreamhost.com>
Reviewed-by: NSage Weil <sage@newdream.net>

In write_partial_msg_pages() there is a local variable used to
track the starting offset within a bio segment to use.  Its name,
"page_shift" defies the Linux convention of using that name for
log-base-2(page size).

Since it's only used in the bio case rename it "bio_offset".  Use it
along with the page_pos field to compute the memory offset when
computing CRC's in that function.  This makes the bio case match the
others more closely.
Signed-off-by: NAlex Elder <elder@dreamhost.com>
Reviewed-by: NSage Weil <sage@newdream.net>

There's not a lot of benefit to zero_page_address, which basically
holds a mapping of the zero page through the life of the messenger
module.  Even with our own mapping, the sendpage interface where
it's used may need to kmap() it again.  It's almost certain to
be in low memory anyway.

So stop treating the zero page specially in write_partial_msg_pages()
and just get rid of zero_page_address entirely.
Signed-off-by: NAlex Elder <elder@dreamhost.com>
Reviewed-by: NSage Weil <sage@newdream.net>

Make ceph_tcp_sendpage() be the only place kernel_sendpage() is
used, by using this helper in write_partial_msg_pages().
Signed-off-by: NAlex Elder <elder@dreamhost.com>
Reviewed-by: NSage Weil <sage@newdream.net>

If a message queued for send gets revoked, zeroes are sent over the
wire instead of any unsent data.  This is done by constructing a
message and passing it to kernel_sendmsg() via ceph_tcp_sendmsg().

Since we are already working with a page in this case we can use
the sendpage interface instead.  Create a new ceph_tcp_sendpage()
helper that sets up flags to match the way ceph_tcp_sendmsg()
does now.
Signed-off-by: NAlex Elder <elder@dreamhost.com>
Reviewed-by: NSage Weil <sage@newdream.net>

CRC's are computed for all messages between ceph entities.  The CRC
computation for the data portion of message can optionally be
disabled using the "nocrc" (common) ceph option.  The default is
for CRC computation for the data portion to be enabled.

Unfortunately, the code that implements this feature interprets the
feature flag wrong, meaning that by default the CRC's have *not*
been computed (or checked) for the data portion of messages unless
the "nocrc" option was supplied.

Fix this, in write_partial_msg_pages() and read_partial_message().
Also change the flag variable in write_partial_msg_pages() to be
"no_datacrc" to match the usage elsewhere in the file.

This fixes http://tracker.newdream.net/issues/2064Signed-off-by: NAlex Elder <elder@dreamhost.com>
Reviewed-by: NSage Weil <sage@newdream.net>

Nothing too big here.
    - define the size of the buffer used for consuming ignored
      incoming data using a symbolic constant
    - simplify the condition determining whether to unmap the page
      in write_partial_msg_pages(): do it for crc but not if the
      page is the zero page
Signed-off-by: NAlex Elder <elder@dreamhost.com>
Signed-off-by: NSage Weil <sage@newdream.net>

Make a small change in the code that counts down kvecs consumed by
a ceph_tcp_sendmsg() call.  Same functionality, just blocked out
a little differently.
Signed-off-by: NAlex Elder <elder@dreamhost.com>
Signed-off-by: NSage Weil <sage@newdream.net>

Move blocks of code out of loops in read_partial_message_section()
and read_partial_message().  They were only was getting called at
the end of the last iteration of the loop anyway.
Signed-off-by: NAlex Elder <elder@dreamhost.com>
Signed-off-by: NSage Weil <sage@newdream.net>

Calculate CRC in a separate step from rearranging the byte order
of the result, to improve clarity and readability.

Use offsetof() to determine the number of bytes to include in the
CRC calculation.

In read_partial_message(), switch which value gets byte-swapped,
since the just-computed CRC is already likely to be in a register.
Signed-off-by: NAlex Elder <elder@dreamhost.com>
Signed-off-by: NSage Weil <sage@newdream.net>

Change the name (and type) of a few CRC-related Boolean local
variables so they contain the word "do", to distingish their purpose
from variables used for holding an actual CRC value.

Note that in the process of doing this I identified a fairly serious
logic error in write_partial_msg_pages():  the value of "do_crc"
assigned appears to be the opposite of what it should be.  No
attempt to fix this is made here; this change preserves the
erroneous behavior.  The problem I found is documented here:
    http://tracker.newdream.net/issues/2064Signed-off-by: NAlex Elder <elder@dreamhost.com>
Signed-off-by: NSage Weil <sage@newdream.net>

This gathers a number of very minor changes:
    - use %hu when formatting the a socket address's address family
    - null out the ceph_msgr_wq pointer after the queue has been
      destroyed
    - drop a needless cast in ceph_write_space()
    - add a WARN() call in ceph_state_change() in the event an
      unrecognized socket state is encountered
    - rearrange the logic in ceph_con_get() and ceph_con_put() so
      that:
        - the reference counts are only atomically read once
	- the values displayed via dout() calls are known to
	  be meaningful at the time they are formatted
Signed-off-by: NAlex Elder <elder@dreamhost.com>
Signed-off-by: NSage Weil <sage@newdream.net>

There is no real need for ceph_tcp_connect() to return the socket
pointer it creates, since it already assigns it to con->sock, which
is visible to the caller.  Instead, have it return an error code,
which tidies things up a bit.
Signed-off-by: NAlex Elder <elder@dreamhost.com>
Signed-off-by: NSage Weil <sage@newdream.net>

Define a helper function to perform various cleanup operations.  Use
it both in the exit routine and in the init routine in the event of
an error.
Signed-off-by: NAlex Elder <elder@dreamhost.com>
Signed-off-by: NSage Weil <sage@newdream.net>

The messenger workqueue has no need to be public.  So give it static
scope.
Signed-off-by: NAlex Elder <elder@dreamhost.com>
Signed-off-by: NSage Weil <sage@newdream.net>

Encapsulate the operation of adding a new chunk of data to the next
open slot in a ceph_connection's out_kvec array.  Also add a "reset"
operation to make subsequent add operations start at the beginning
of the array again.

Use these routines throughout, avoiding duplicate code and ensuring
all calls are handled consistently.
Signed-off-by: NAlex Elder <elder@dreamhost.com>
Signed-off-by: NSage Weil <sage@newdream.net>

One of the arguments to prepare_write_connect() indicates whether it
is being called immediately after a call to prepare_write_banner().
Move the prepare_write_banner() call inside prepare_write_connect(),
and reinterpret (and rename) the "after_banner" argument so it
indicates that prepare_write_connect() should *make* the call
rather than should know it has already been made.

This was split out from the next patch to highlight this change in
logic.
Signed-off-by: NAlex Elder <elder@dreamhost.com>
Signed-off-by: NSage Weil <sage@newdream.net>

This fixes some spots where a type cast to (void *) was used as
as a universal type hiding mechanism.  Instead, properly cast the
type to the intended target type.
Signed-off-by: NAlex Elder <elder@newdream.net>
Signed-off-by: NSage Weil <sage@newdream.net>

This eliminates type casts in some places where they are not
required.
Signed-off-by: NAlex Elder <elder@newdream.net>
Signed-off-by: NSage Weil <sage@newdream.net>

A spinlock is used to protect a value used for selecting an array
index for a string used for formatting a socket address for human
consumption.  The index is reset to 0 if it ever reaches the maximum
index value.

Instead, use an ever-increasing atomic variable as a sequence
number, and compute the array index by masking off all but the
sequence number's lowest bits.  Make the number of entries in the
array a power of two to allow the use of such a mask (to avoid jumps
in the index value when the sequence number wraps).

The length of these strings is somewhat arbitrarily set at 60 bytes.
The worst-case length of a string produced is 54 bytes, for an IPv6
address that can't be shortened, e.g.:
    [1234:5678:9abc:def0:1111:2222:123.234.210.100]:32767
Change it so we arbitrarily use 64 bytes instead; if nothing else
it will make the array of these line up better in hex dumps.

Rename a few things to reinforce the distinction between the number
of strings in the array and the length of individual strings.
Signed-off-by: NAlex Elder <elder@newdream.net>
Signed-off-by: NSage Weil <sage@newdream.net>

Rearrange ceph_tcp_connect() a bit, making use of "else" rather than
re-testing a value with consecutive "if" statements.  Don't record a
connection's socket pointer unless the connect operation is
successful.
Signed-off-by: NAlex Elder <elder@dreamhost.com>
Signed-off-by: NSage Weil <sage@newdream.net>

Each messenger allocates a page to be used when writing zeroes
out in the event of error or other abnormal condition.  Instead,
use the kernel ZERO_PAGE() for that purpose.
Signed-off-by: NAlex Elder <elder@dreamhost.com>
Signed-off-by: NSage Weil <sage@newdream.net>

The Ceph messenger would sometimes queue multiple work items to write
data to a socket when the socket buffer was full.

Fix this problem by making ceph_write_space() use SOCK_NOSPACE in the
same way that net/core/stream.c:sk_stream_write_space() does, i.e.,
clearing it only when sufficient space is available in the socket buffer.
Signed-off-by: NJim Schutt <jaschut@sandia.gov>
Reviewed-by: NAlex Elder <elder@dreamhost.com>

These files are non modular, but need to export symbols using
the macros now living in export.h -- call out the include so
that things won't break when we remove the implicit presence
of module.h from everywhere.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

Change ceph_parse_ips to take either names given as
IP addresses or standard hostnames (e.g. localhost).
The DNS lookup is done using the dns_resolver facility
similar to its use in AFS, NFS, and CIFS.

This patch defines CONFIG_CEPH_LIB_USE_DNS_RESOLVER
that controls if this feature is on or off.
Signed-off-by: NNoah Watkins <noahwatkins@gmail.com>
Signed-off-by: NSage Weil <sage@newdream.net>