linux/include
Alex Elder ca8b3a6917 libceph: implement multiple data items in a message
This patch adds support to the messenger for more than one data item
in its data list.

A message data cursor has two more fields to support this:
    - a count of the number of bytes left to be consumed across
      all data items in the list, "total_resid"
    - a pointer to the head of the list (for validation only)

The cursor initialization routine has been split into two parts: the
outer one, which initializes the cursor for traversing the entire
list of data items; and the inner one, which initializes the cursor
to start processing a single data item.

When a message cursor is first initialized, the outer initialization
routine sets total_resid to the length provided.  The data pointer
is initialized to the first data item on the list.  From there, the
inner initialization routine finishes by setting up to process the
data item the cursor points to.

Advancing the cursor consumes bytes in total_resid.  If the resid
field reaches zero, it means the current data item is fully
consumed.  If total_resid indicates there is more data, the cursor
is advanced to point to the next data item, and then the inner
initialization routine prepares for using that.  (A check is made at
this point to make sure we don't wrap around the front of the list.)

The type-specific init routines are modified so they can be given a
length that's larger than what the data item can support.  The resid
field is initialized to the smaller of the provided length and the
length of the entire data item.

When total_resid reaches zero, we're done.

This resolves:
    http://tracker.ceph.com/issues/3761

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01 21:18:33 -07:00
..
acpi Fixes: 2013-03-12 20:25:53 -07:00
asm-generic x86-32: Fix possible incomplete TLB invalidate with PAE pagetables 2013-04-12 16:56:47 -07:00
clocksource ImgTec Meta architecture changes for v3.9-rc1 2013-03-03 12:06:09 -08:00
crypto
drm drm/radeon: add Richland pci ids 2013-03-15 18:47:19 -04:00
keys
linux libceph: implement multiple data items in a message 2013-05-01 21:18:33 -07:00
math-emu
media
memory
misc
net net: fix incorrect credentials passing 2013-04-20 16:56:42 -04:00
pcmcia
ras
rdma IB/core: Add "type 2" memory windows support 2013-02-21 11:51:45 -08:00
rxrpc
scsi libfc, fcoe, bnx2fc: Split fc_disc_init into fc_disc_{init, config} 2013-03-25 16:03:03 -07:00
sound Merge remote-tracking branch 'asoc/fix/max98090' into asoc-next 2013-03-26 14:08:03 +00:00
target target: Rename spc_get_write_same_sectors -> sbc_get_write_same_sectors 2013-02-23 12:46:14 -08:00
trace Revert "block: add missing block_bio_complete() tracepoint" 2013-04-18 09:00:26 -07:00
uapi fuse: fix type definitions in uapi header 2013-04-17 12:30:40 +02:00
video ARM: at91: fix LCD-wiring mode 2013-03-13 11:05:04 +01:00
xen for-linus-20130331 2013-03-31 11:38:59 -07:00
Kbuild