Commit 100766f8 authored by Jeff Layton's avatar Jeff Layton Committed by J. Bruce Fields
Browse files

nfsd: treat all shutdown signals as equivalent 



knfsd currently uses 2 signal masks when processing requests. A "loose"
mask (SHUTDOWN_SIGS) that it uses when receiving network requests, and
then a more "strict" mask (ALLOWED_SIGS, which is just SIGKILL) that it
allows when doing the actual operation on the local storage.

This is apparently unnecessarily complicated. The underlying filesystem
should be able to sanely handle a signal in the middle of an operation.
This patch removes the signal mask handling from knfsd altogether. When
knfsd is started as a kthread, all signals are ignored. It then allows
all of the signals in SHUTDOWN_SIGS. There's no need to set the mask
as well.

Signed-off-by: default avatarJeff Layton <jlayton@redhat.com>
Signed-off-by: default avatarJ. Bruce Fields <bfields@citi.umich.edu>
parent 3cd2cfea

fs/nfsd/nfssvc.c

+5 −25
Original line number Diff line number Diff line
@@ -37,15 +37,6 @@ 


#define NFSDDBG_FACILITY	NFSDDBG_SVC



/* these signals will be delivered to an nfsd thread 

 * when handling a request

 */

#define ALLOWED_SIGS	(sigmask(SIGKILL))

/* these signals will be delivered to an nfsd thread

 * when not handling a request. i.e. when waiting

 */

#define SHUTDOWN_SIGS	(sigmask(SIGKILL) | sigmask(SIGHUP) | sigmask(SIGINT) | sigmask(SIGQUIT))



extern struct svc_program	nfsd_program;

static int			nfsd(void *vrqstp);

struct timeval			nfssvc_boot;
@@ -414,9 +405,7 @@ nfsd(void *vrqstp) 
{

	struct svc_rqst *rqstp = (struct svc_rqst *) vrqstp;

	struct fs_struct *fsp;

	sigset_t shutdown_mask, allowed_mask;

	int err, preverr = 0;

	unsigned int signo;



	/* Lock module and set up kernel thread */

	mutex_lock(&nfsd_mutex);
@@ -433,17 +422,14 @@ nfsd(void *vrqstp) 
	current->fs = fsp;

	current->fs->umask = 0;



	siginitsetinv(&shutdown_mask, SHUTDOWN_SIGS);

	siginitsetinv(&allowed_mask, ALLOWED_SIGS);



	/*

	 * thread is spawned with all signals set to SIG_IGN, re-enable

	 * the ones that matter

	 * the ones that will bring down the thread

	 */

	for (signo = 1; signo <= _NSIG; signo++) {

		if (!sigismember(&shutdown_mask, signo))

			allow_signal(signo);

	}

	allow_signal(SIGKILL);

	allow_signal(SIGHUP);

	allow_signal(SIGINT);

	allow_signal(SIGQUIT);



	nfsdstats.th_cnt++;

	mutex_unlock(&nfsd_mutex);
@@ -460,9 +446,6 @@ nfsd(void *vrqstp) 
	 * The main request loop

	 */

	for (;;) {

		/* Block all but the shutdown signals */

		sigprocmask(SIG_SETMASK, &shutdown_mask, NULL);



		/*

		 * Find a socket with data available and call its

		 * recvfrom routine.
@@ -487,9 +470,6 @@ nfsd(void *vrqstp) 
		/* Lock the export hash tables for reading. */

		exp_readlock();



		/* Process request with signals blocked. */

		sigprocmask(SIG_SETMASK, &allowed_mask, NULL);



		svc_process(rqstp);



		/* Unlock export hash tables */

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