linux.git/net/9p, branch v2.6.39

net/9p/protocol.c: Fix a memory leak

2011-05-12T22:05:37+00:00

When p9pdu_readf() is called with "s" attribute, it allocates a pointer that
will store a string. In p9dirent_read(), this pointer is not being released,
leading to out of memory errors.
This patch releases this pointer after string is copyed to dirent->d_name.

Signed-off-by: Pedro Scarapicchia Junior 
Signed-off-by: Eric Van Hensbergen

net/9p: Handle get_user_pages_fast return properly

2011-05-10T03:51:12+00:00

Use proper data type to handle get_user_pages_fast error condition. Also
do not treat EFAULT error as fatal.

Signed-off-by: M. Mohan Kumar 
Signed-off-by: Venkateswararao Jujjuri 
Signed-off-by: Eric Van Hensbergen

net/9p: nwname should be an unsigned int

2011-04-15T20:26:15+00:00

Signed-off-by: Harsh Prateek Bora 
Signed-off-by: Venkateswararao Jujjuri 
Signed-off-by: Eric VAn Hensbergen

9p: Fix sparse error

2011-04-15T20:26:14+00:00

Signed-off-by: Aneesh Kumar K.V 
Signed-off-by: Venkateswararao Jujjuri 
Signed-off-by: Eric Van Hensbergen

9p: revert tsyncfs related changes

2011-04-15T20:26:14+00:00

Now that we use write_inode to flush server
cache related to fid, we don't need tsyncfs either fort dotl or dotu
protocols. For dotu this helps to do a more efficient server flush.

Signed-off-by: Aneesh Kumar K.V 
Signed-off-by: Venkateswararao Jujjuri 
Signed-off-by: Eric Van Hensbergen

Fix common misspellings

2011-03-31T14:26:23+00:00

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi

[net/9p]: Introduce basic flow-control for VirtIO transport.

2011-03-22T21:32:50+00:00

Recent zerocopy work in the 9P VirtIO transport maps and pins
user buffers into kernel memory for the server to work on them.
Since the user process can initiate this kind of pinning with a simple
read/write call, thousands of IO threads initiated by the user process can
hog the system resources and could result into denial of service.

This patch introduces flow control to avoid that extreme scenario.

The ceiling limit to avoid denial of service attacks is set to relatively
high (nr_free_pagecache_pages()/4) so that it won't interfere with
regular usage, but can step in extreme cases to limit the total system
hang. Since we don't have a global structure to accommodate this variable,
I choose the virtio_chan as the home for this.

Signed-off-by: Venkateswararao Jujjuri 
Reviewed-by: Badari Pulavarty 
Signed-off-by: Eric Van Hensbergen

[net/9p] Don't re-pin pages on retrying virtqueue_add_buf().

2011-03-22T21:32:48+00:00

Signed-off-by: Venkateswararao Jujjuri 
Signed-off-by: Eric Van Hensbergen

[net/9p] Set the condition just before waking up.

2011-03-22T21:32:47+00:00

Given that the sprious wake-ups are common, we need to move the
condition setting right next to the wake_up().  After setting the condition
to req->status = REQ_STATUS_RCVD, sprious wakeups may cause the
virtqueue back on the free list for someone else to use.
This may result in kernel panic while relasing the pinned pages
in p9_release_req_pages().

Also rearranged the while loop in req_done() for better redability.

Signed-off-by: Venkateswararao Jujjuri 
Signed-off-by: Eric Van Hensbergen

[net/9p] unconditional wake_up to proc waiting for space on VirtIO ring

2011-03-22T21:32:19+00:00

Process may wait to get space on VirtIO ring to send a transaction to
VirtFS server. Current code just does a conditional wake_up() which
means only one process will be woken up even if multiple processes
are waiting.

This fix makes the wake_up unconditional. Hence we won't have any
processes waiting for-ever.

Signed-off-by: Venkateswararao Jujjuri 
Signed-off-by: Eric Van Hensbergen