these pieces of code only make sense when CONFIG_NFSD_DEPRECATED enabled
Signed-off-by: Jovi Zhang <bookjovi@gmail.com>
fs/nfsd/nfsctl.c | 2 ++
1 files changed, 2 insertions(+), 0 deletions(-)
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
* 'for-2.6.37' of git://linux-nfs.org/~bfields/linux: (99 commits)
svcrpc: svc_tcp_sendto XPT_DEAD check is redundant
svcrpc: no need for XPT_DEAD check in svc_xprt_enqueue
svcrpc: assume svc_delete_xprt() called only once
svcrpc: never clear XPT_BUSY on dead xprt
nfsd4: fix connection allocation in sequence()
nfsd4: only require krb5 principal for NFSv4.0 callbacks
nfsd4: move minorversion to client
nfsd4: delay session removal till free_client
nfsd4: separate callback change and callback probe
nfsd4: callback program number is per-session
nfsd4: track backchannel connections
nfsd4: confirm only on succesful create_session
nfsd4: make backchannel sequence number per-session
nfsd4: use client pointer to backchannel session
nfsd4: move callback setup into session init code
nfsd4: don't cache seq_misordered replies
SUNRPC: Properly initialize sock_xprt.srcaddr in all cases
SUNRPC: Use conventional switch statement when reclassifying sockets
sunrpc/xprtrdma: clean up workqueue usage
sunrpc: Turn list_for_each-s into the ..._entry-s
...
Fix up trivial conflicts (two different deprecation notices added in
separate branches) in Documentation/feature-removal-schedule.txt
All file_operations should get a .llseek operation so we can make
nonseekable_open the default for future file operations without a
.llseek pointer.
The three cases that we can automatically detect are no_llseek, seq_lseek
and default_llseek. For cases where we can we can automatically prove that
the file offset is always ignored, we use noop_llseek, which maintains
the current behavior of not returning an error from a seek.
New drivers should normally not use noop_llseek but instead use no_llseek
and call nonseekable_open at open time. Existing drivers can be converted
to do the same when the maintainer knows for certain that no user code
relies on calling seek on the device file.
The generated code is often incorrectly indented and right now contains
comments that clarify for each added line why a specific variant was
chosen. In the version that gets submitted upstream, the comments will
be gone and I will manually fix the indentation, because there does not
seem to be a way to do that using coccinelle.
Some amount of new code is currently sitting in linux-next that should get
the same modifications, which I will do at the end of the merge window.
Many thanks to Julia Lawall for helping me learn to write a semantic
patch that does all this.
===== begin semantic patch =====
// This adds an llseek= method to all file operations,
// as a preparation for making no_llseek the default.
//
// The rules are
// - use no_llseek explicitly if we do nonseekable_open
// - use seq_lseek for sequential files
// - use default_llseek if we know we access f_pos
// - use noop_llseek if we know we don't access f_pos,
// but we still want to allow users to call lseek
//
@ open1 exists @
identifier nested_open;
@@
nested_open(...)
{
<+...
nonseekable_open(...)
...+>
}
@ open exists@
identifier open_f;
identifier i, f;
identifier open1.nested_open;
@@
int open_f(struct inode *i, struct file *f)
{
<+...
(
nonseekable_open(...)
|
nested_open(...)
)
...+>
}
@ read disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}
@ read_no_fpos disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
... when != off
}
@ write @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}
@ write_no_fpos @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
... when != off
}
@ fops0 @
identifier fops;
@@
struct file_operations fops = {
...
};
@ has_llseek depends on fops0 @
identifier fops0.fops;
identifier llseek_f;
@@
struct file_operations fops = {
...
.llseek = llseek_f,
...
};
@ has_read depends on fops0 @
identifier fops0.fops;
identifier read_f;
@@
struct file_operations fops = {
...
.read = read_f,
...
};
@ has_write depends on fops0 @
identifier fops0.fops;
identifier write_f;
@@
struct file_operations fops = {
...
.write = write_f,
...
};
@ has_open depends on fops0 @
identifier fops0.fops;
identifier open_f;
@@
struct file_operations fops = {
...
.open = open_f,
...
};
// use no_llseek if we call nonseekable_open
////////////////////////////////////////////
@ nonseekable1 depends on !has_llseek && has_open @
identifier fops0.fops;
identifier nso ~= "nonseekable_open";
@@
struct file_operations fops = {
... .open = nso, ...
+.llseek = no_llseek, /* nonseekable */
};
@ nonseekable2 depends on !has_llseek @
identifier fops0.fops;
identifier open.open_f;
@@
struct file_operations fops = {
... .open = open_f, ...
+.llseek = no_llseek, /* open uses nonseekable */
};
// use seq_lseek for sequential files
/////////////////////////////////////
@ seq depends on !has_llseek @
identifier fops0.fops;
identifier sr ~= "seq_read";
@@
struct file_operations fops = {
... .read = sr, ...
+.llseek = seq_lseek, /* we have seq_read */
};
// use default_llseek if there is a readdir
///////////////////////////////////////////
@ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier readdir_e;
@@
// any other fop is used that changes pos
struct file_operations fops = {
... .readdir = readdir_e, ...
+.llseek = default_llseek, /* readdir is present */
};
// use default_llseek if at least one of read/write touches f_pos
/////////////////////////////////////////////////////////////////
@ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read.read_f;
@@
// read fops use offset
struct file_operations fops = {
... .read = read_f, ...
+.llseek = default_llseek, /* read accesses f_pos */
};
@ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write.write_f;
@@
// write fops use offset
struct file_operations fops = {
... .write = write_f, ...
+ .llseek = default_llseek, /* write accesses f_pos */
};
// Use noop_llseek if neither read nor write accesses f_pos
///////////////////////////////////////////////////////////
@ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
identifier write_no_fpos.write_f;
@@
// write fops use offset
struct file_operations fops = {
...
.write = write_f,
.read = read_f,
...
+.llseek = noop_llseek, /* read and write both use no f_pos */
};
@ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write_no_fpos.write_f;
@@
struct file_operations fops = {
... .write = write_f, ...
+.llseek = noop_llseek, /* write uses no f_pos */
};
@ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
@@
struct file_operations fops = {
... .read = read_f, ...
+.llseek = noop_llseek, /* read uses no f_pos */
};
@ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
@@
struct file_operations fops = {
...
+.llseek = noop_llseek, /* no read or write fn */
};
===== End semantic patch =====
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Julia Lawall <julia@diku.dk>
Cc: Christoph Hellwig <hch@infradead.org>
There are two calls that operate on ip_map_cache and are
directly called from the nfsd code. Other places will be
handled in a different way.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The git://linux-nfs.org/~bfields/linux.git nfsd-next branch doesn't
compile when nfsd is a module with the following error:
ERROR: "get_task_comm" [fs/nfsd/nfsd.ko] undefined!
Replace the get_task_comm call with direct comm access, which is
safe for current.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Add CONFIG_NFSD_DEPRECATED, default to y.
Only include deprecated interface if this is defined.
This allows distros to remove this interface before the official
removal, and allows developers to test without it.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The syscall interface is has been replaced by a more flexible
interface since 2.6.0. It is time to work towards discarding
the old interface.
So add a entry in feature-removal-schedule.txt and print a warning
when the interface is used.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
It's harmless to set this after the server is created, but also
ineffective, since the value is only used at the time of
svc_create_pooled(). So fail the attempt, in keeping with the pattern
set by write_versions, write_{lease,grace}time and write_recoverydir.
(This could break userspace that tried to write to nfsd/max_block_size
between setting up sockets and starting the server. However, such code
wouldn't have worked anyway, and I don't know of any examples--rpc.nfsd
in nfs-utils, probably the only user of the interface, doesn't do that.)
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Fixes at least one real minor bug: the nfs4 recovery dir sysctl
would not return its status properly.
Also I finished Al's 1e41568d73 ("Take ima_path_check() in nfsd
past dentry_open() in nfsd_open()") commit, it moved the IMA
code, but left the old path initializer in there.
The rest is just dead code removed I think, although I was not
fully sure about the "is_borc" stuff. Some more review
would be still good.
Found by gcc 4.6's new warnings.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Right now, nfsd keeps a lockd reference for each socket that it has
open. This is unnecessary and complicates the error handling on
startup and shutdown. Change it to just do a lockd_up when starting
the first nfsd thread just do a single lockd_down when taking down the
last nfsd thread. Because of the strange way the sv_count is handled
this requires an extra flag to tell whether the nfsd_serv holds a
reference for lockd or not.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
__write_ports_addxprt calls nfsd_create_serv. That increases the
refcount of nfsd_serv (which is tracked in sv_nrthreads). The service
only decrements the thread count on error, not on success like
__write_ports_addfd does, so using this interface leaves the nfsd
thread count high.
Fix this by having this function call svc_destroy() on error to release
the reference (and possibly to tear down the service) and simply
decrement the refcount without tearing down the service on success.
This makes the sv_threads handling work basically the same in both
__write_ports_addxprt and __write_ports_addfd.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The refcounting for nfsd is a little goofy. What happens is that we
create the nfsd RPC service, attach sockets to it but don't actually
start the threads until someone writes to the "threads" procfile. To do
this, __write_ports_addfd will create the nfsd service and then will
decrement the refcount when exiting but won't actually destroy the
service.
This is fine when there aren't errors, but when there are this can
cause later attempts to start nfsd to fail. nfsd_serv will be set,
and that causes __write_versions to return EBUSY.
Fix this by calling svc_destroy on nfsd_serv when this function is
going to return error.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
- C99 knows about USHRT_MAX/SHRT_MAX/SHRT_MIN, not
USHORT_MAX/SHORT_MAX/SHORT_MIN.
- Make SHRT_MIN of type s16, not int, for consistency.
[akpm@linux-foundation.org: fix drivers/dma/timb_dma.c]
[akpm@linux-foundation.org: fix security/keys/keyring.c]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
The current documentation here is out of date, and not quite right.
(Future work: some user documentation would be useful.)
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Instead of accessing the lease time directly, some users call
nfs4_lease_time(), and some a macro, NFSD_LEASE_TIME, defined as
nfs4_lease_time(). Neither layer of indirection serves any purpose.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Try to create a PF_INET6 listener for NFSD, if IPv6 is enabled in the
kernel.
Make sure nfsd_serv's reference count is decreased if
__write_ports_addxprt() failed to create a listener. See
__write_ports_addfd().
Our current plan is to rely on rpc.nfsd to create appropriate IPv6
listeners when server-side NFS/IPv6 support is desired. Legacy
behavior, via the write_threads or write_svc kernel APIs, will remain
the same -- only IPv4 listeners are created.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
[bfields@citi.umich.edu: Move error-handling code to end]
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
write_ports() converts svc_create_xprt()'s ENOENT error return to
EPROTONOSUPPORT so that rpc.nfsd (in user space) can report an error
message that makes sense.
It turns out that several of the other kernel APIs rpc.nfsd use can
also return ENOENT from svc_create_xprt(), by way of lockd_up().
On the client side, an NFSv2 or NFSv3 mount request can also return
the result of lockd_up(). This error may also be returned during an
NFSv4 mount request, since the NFSv4 callback service uses
svc_create_xprt() to create the callback listener. An ENOENT error
return results in a confusing error message from the mount command.
Let's have svc_create_xprt() return EPROTONOSUPPORT instead of ENOENT.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
The new .h files have paths at the top that are now out of date. While
we're here, just remove all of those from fs/nfsd; they never served any
purpose.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Soon we will add the new V4ROOT flag, and allow the INSECURE flag to
vary by pseudoflavor. It would be useful for nfs-utils (for example,
for improved exportfs error reporting) to be able to know when this
happens. Use this new interface for that purpose.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Lots of include/linux/nfsd/* headers are only used by
nfsd module. Move them to the source directory
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Now that the headers are fixed and carry their own wait, all fs/nfsd/
source files can include a minimal set of headers. and still compile just
fine.
This patch should improve the compilation speed of the nfsd module.
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
lock_kernel() in knfsd was replaced with a mutex. The later
commit 03cf6c9f49 ("knfsd:
add file to export stats about nfsd pools") did not follow
that change. This patch fixes the issue.
Also move the get and put of nfsd_serv to the open and close methods
(instead of start and stop methods) to allow atomic check and increment
of reference count in the open method (where we can still return an
error).
Signed-off-by: Ryusei Yamaguchi <mandel59@gmail.com>
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Cc: Greg Banks <gnb@fmeh.org>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
In write_failover_ip(), replace the sscanf() with a call to the common
sunrpc.ko presentation address parser.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
kmemleak produces the following warning
unreferenced object 0xc9ec02a0 (size 8):
comm "cat", pid 19048, jiffies 730243
backtrace:
[<c01bf970>] create_object+0x100/0x240
[<c01bfadb>] kmemleak_alloc+0x2b/0x60
[<c01bcd4b>] __kmalloc+0x14b/0x270
[<c02fd027>] write_pool_threads+0x87/0x1d0
[<c02fcc08>] nfsctl_transaction_write+0x58/0x70
[<c02fcc6f>] nfsctl_transaction_read+0x4f/0x60
[<c01c2574>] vfs_read+0x94/0x150
[<c01c297d>] sys_read+0x3d/0x70
[<c0102d6b>] sysenter_do_call+0x12/0x32
[<ffffffff>] 0xffffffff
write_pool_threads() only frees nthreads on error paths, in the success case
we leak it.
Signed-off-by: Eric Sesterhenn <eric.sesterhenn@lsexperts.de>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
* Remove smp_lock.h from files which don't need it (including some headers!)
* Add smp_lock.h to files which do need it
* Make smp_lock.h include conditional in hardirq.h
It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT
This will make hardirq.h inclusion cheaper for every PREEMPT=n config
(which includes allmodconfig/allyesconfig, BTW)
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently when we write a number to 'threads' in nfsdfs,
we take the nfsd_mutex, update the number of threads, then take the
mutex again to read the number of threads.
Mostly this isn't a big deal. However if we are write '0', and
portmap happens to be dead, then we can get unpredictable behaviour.
If the nfsd threads all got killed quickly and the last thread is
waiting for portmap to respond, then the second time we take the mutex
we will block waiting for the last thread.
However if the nfsd threads didn't die quite that fast, then there
will be no contention when we try to take the mutex again.
Unpredictability isn't fun, and waiting for the last thread to exit is
pointless, so avoid taking the lock twice.
To achieve this, get nfsd_svc return a non-negative number of active
threads when not returning a negative error.
Signed-off-by: NeilBrown <neilb@suse.de>
Clean up: For consistency, handle output buffer size checking in a
other nfsctl functions the same way it's done for write_versions().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
While it's not likely today that there are enough NFS versions to
overflow the output buffer in write_versions(), we should be more
careful about detecting the end of the buffer.
The number of NFS versions will only increase as NFSv4 minor versions
are added.
Note that this API doesn't behave the same as portlist. Here we
attempt to display as many versions as will fit in the buffer, and do
not provide any indication that an overflow would have occurred. I
don't have any good rationale for that.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
While it's not likely a pathname will be longer than
SIMPLE_TRANSACTION_SIZE, we should be more careful about just
plopping it into the output buffer without bounds checking.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Adjust the synopsis of svc_sock_names() to pass in the size of the
output buffer. Add a documenting comment.
This is a cosmetic change for now. A subsequent patch will make sure
the buffer length is passed to one_sock_name(), where the length will
actually be useful.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Adjust the synopsis of svc_addsock() to pass in the size of the output
buffer. Add a documenting comment.
This is a cosmetic change for now. A subsequent patch will make sure
the buffer length is passed to one_sock_name(), where the length will
actually be useful.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
The svc_xprt_names() function can overflow its buffer if it's so near
the end of the passed in buffer that the "name too long" string still
doesn't fit. Of course, it could never tell if it was near the end
of the passed in buffer, since its only caller passes in zero as the
buffer length.
Let's make this API a little safer.
Change svc_xprt_names() so it *always* checks for a buffer overflow,
and change its only caller to pass in the correct buffer length.
If svc_xprt_names() does overflow its buffer, it now fails with an
ENAMETOOLONG errno, instead of trying to write a message at the end
of the buffer. I don't like this much, but I can't figure out a clean
way that's always safe to return some of the names, *and* an
indication that the buffer was not long enough.
The displayed error when doing a 'cat /proc/fs/nfsd/portlist' is
"File name too long".
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Clean up.
A couple of years ago, a series of commits, finishing with commit
5680c446, swapped the order of the lockd_up() and svc_addsock() calls
in __write_ports(). At that time lockd_up() needed to know the
transport protocol of the passed-in socket to start a listener on the
same transport protocol.
These days, lockd_up() doesn't take a protocol argument; it always
starts both a UDP and TCP listener. It's now more straightforward to
try the lockd_up() first, then do a lockd_down() if the svc_addsock()
fails.
Careful review of this code shows that the svc_sock_names() call is
used only to close the just-opened socket in case lockd_up() fails.
So it is no longer needed if lockd_up() is done first.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Clean up: Refactor transport name listing out of __write_ports() to
make it easier to understand and maintain.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
User space must call listen(3) on SOCK_STREAM sockets passed into
/proc/fs/nfsd/portlist, otherwise that listener is ignored. Document
this.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Clean up: Refactor the socket creation logic out of __write_ports() to
make it easier to understand and maintain.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Clean up: Refactor the socket closing logic out of __write_ports() to
make it easier to understand and maintain.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Clean up: Refactor transport addition out of __write_ports() to make
it easier to understand and maintain.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Clean up: Refactor transport removal out of __write_ports() to make it
easier to understand and maintain.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
J. Bruce Fields