svn commit: r349286 - in head: sbin/swapon share/man/man5

[Konstantin Belousov]

On Sat, Jun 22, 2019 at 03:16:02AM +0000, Doug Moore wrote:
> Author: dougm
> Date: Sat Jun 22 03:16:01 2019
> New Revision: 349286
> URL: https://svnweb.freebsd.org/changeset/base/349286
> 
> Log:
>   Modify swapon(8) to invoke BIO_DELETE to trim swap devices, either if
>   '-E' appears on the swapon command line, or if "trimonce" appears as
>   an fstab option.
>   
>   Discussed at: BSDCAN
>   Tested by: markj
>   Reviewed by: markj
>   Approved by: markj (mentor)
>   Differential Revision:https://reviews.freebsd.org/D20599
> 
> Modified:
>   head/sbin/swapon/swapon.8
>   head/sbin/swapon/swapon.c
>   head/share/man/man5/fstab.5
> 
> Modified: head/sbin/swapon/swapon.8
> ==============================================================================
> --- head/sbin/swapon/swapon.8	Sat Jun 22 01:20:45 2019	(r349285)
> +++ head/sbin/swapon/swapon.8	Sat Jun 22 03:16:01 2019	(r349286)
> @@ -28,7 +28,7 @@
>  .\"     @(#)swapon.8	8.1 (Berkeley) 6/5/93
>  .\" $FreeBSD$
>  .\"
> -.Dd October 21, 2016
> +.Dd June 21, 2019
>  .Dt SWAPON 8
>  .Os
>  .Sh NAME
> @@ -38,7 +38,7 @@
>  .Nm swapon
>  .Oo Fl F Ar fstab
>  .Oc
> -.Fl aLq | Ar
> +.Fl aLq | E Ar
>  .Nm swapoff
>  .Oo Fl F Ar fstab
>  .Oc
> @@ -86,6 +86,11 @@ If the
>  option is used,
>  informational messages will not be
>  written to standard output when a swap device is added.
> +The
> +.Fl E
> +option causes each of following devices to receive a
> +.Dv BIO_DELETE
> +command to mark all blocks as unused.
>  .Pp
>  The
>  .Nm swapoff
> 
> Modified: head/sbin/swapon/swapon.c
> ==============================================================================
> --- head/sbin/swapon/swapon.c	Sat Jun 22 01:20:45 2019	(r349285)
> +++ head/sbin/swapon/swapon.c	Sat Jun 22 03:16:01 2019	(r349286)
> @@ -43,6 +43,7 @@ static char sccsid[] = "@(#)swapon.c	8.1 (Berkeley) 6/
>  #include <sys/cdefs.h>
>  __FBSDID("$FreeBSD$");
>  
> +#include <sys/disk.h>
>  #include <sys/param.h>
>  #include <sys/types.h>
>  #include <sys/mdioctl.h>
> @@ -77,7 +78,7 @@ static int run_cmd(int *, const char *, ...) __printfl
>  
>  static enum { SWAPON, SWAPOFF, SWAPCTL } orig_prog, which_prog = SWAPCTL;
>  
> -static int qflag;
> +static int Eflag, qflag;
>  
>  int
>  main(int argc, char **argv)
> @@ -100,7 +101,7 @@ main(int argc, char **argv)
>  	
>  	doall = 0;
>  	etc_fstab = NULL;
> -	while ((ch = getopt(argc, argv, "AadghklLmqsUF:")) != -1) {
> +	while ((ch = getopt(argc, argv, "AadEghklLmqsUF:")) != -1) {
>  		switch(ch) {
>  		case 'A':
>  			if (which_prog == SWAPCTL) {
> @@ -121,6 +122,12 @@ main(int argc, char **argv)
>  			else
>  				usage();
>  			break;
> +		case 'E':
> +			if (which_prog == SWAPON)
> +				Eflag = 2;
> +			else
> +				usage();
> +			break;
>  		case 'g':
>  			hflag = 'G';
>  			break;
> @@ -182,8 +189,10 @@ main(int argc, char **argv)
>  				    strstr(fsp->fs_mntops, "late") == NULL &&
>  				    late != 0)
>  					continue;
> +				Eflag |= (strstr(fsp->fs_mntops, "trimonce") != NULL);
>  				swfile = swap_on_off(fsp->fs_spec, 1,
>  				    fsp->fs_mntops);
> +				Eflag &= ~1;
>  				if (swfile == NULL) {
>  					ret = 1;
>  					continue;
> @@ -378,12 +387,22 @@ swap_on_geli_args(const char *mntops)
>  					return (NULL);
>  				}
>  			} else if (strcmp(token, "notrim") == 0) {
> +				if (Eflag) {
> +					warn("Options \"notrim\" and "
> +					    "\"trimonce\" conflict");
> +					free(ops);
> +					return (NULL);
> +				}
>  				Tflag = " -T ";
>  			} else if (strcmp(token, "late") == 0) {
>  				/* ignore known option */
>  			} else if (strcmp(token, "noauto") == 0) {
>  				/* ignore known option */
> -			} else if (strcmp(token, "sw") != 0) {
> +			} else if (strcmp(token, "sw") == 0) {
> +				/* ignore known option */
> +			} else if (strcmp(token, "trimonce") == 0) {
> +				/* ignore known option */
> +			} else {
>  				warnx("Invalid option: %s", token);
>  				free(ops);
>  				return (NULL);
> @@ -721,14 +740,42 @@ run_cmd(int *ofd, const char *cmdline, ...)
>  	return (WEXITSTATUS(status));
>  }
>  
> +static void
> +swap_trim(const char *name)
> +{
> +	struct stat sb;
> +	off_t ioarg[2], sz;
> +	int fd;
> +
> +	fd = open(name, O_WRONLY);
> +	if (fd < 0)
> +		errx(1, "Cannot open %s", name);
> +	if (fstat(fd, &sb) < 0)
> +		errx(1, "Cannot stat %s", name);
> +	if (S_ISREG(sb.st_mode))
> +		sz = sb.st_size;
> +	else if (S_ISCHR(sb.st_mode) || S_ISBLK(sb.st_mode)) {
S_ISBLK check is useless or even wrong.

> +		if (ioctl(fd, DIOCGMEDIASIZE, &sz) != 0)
> +			err(1, "ioctl(DIOCGMEDIASIZE)");
> +	} else
> +		errx(1, "%s has an invalid file type", name);
> +	ioarg[0] = 0;
> +	ioarg[1] = sz;
> +	if (ioctl(fd, DIOCGDELETE, ioarg) != 0)
> +		warn("ioctl(DIOCGDELETE)");
> +	close(fd);
> +}
> +
>  static const char *
>  swap_on_off_sfile(const char *name, int doingall)
>  {
>  	int error;
>  
> -	if (which_prog == SWAPON)
> +	if (which_prog == SWAPON) {
> +		if (Eflag)
> +			swap_trim(name);
>  		error = swapon(name);
> -	else /* SWAPOFF */
> +	} else /* SWAPOFF */
>  		error = swapoff(name);
>  
>  	if (error == -1) {
> @@ -759,6 +806,8 @@ usage(void)
>  	fprintf(stderr, "usage: %s ", getprogname());
>  	switch(orig_prog) {
>  	case SWAPON:
> +	    fprintf(stderr, "[-F fstab] -aLq | [-E] file ...\n");
> +	    break;
>  	case SWAPOFF:
>  	    fprintf(stderr, "[-F fstab] -aLq | file ...\n");
>  	    break;
> 
> Modified: head/share/man/man5/fstab.5
> ==============================================================================
> --- head/share/man/man5/fstab.5	Sat Jun 22 01:20:45 2019	(r349285)
> +++ head/share/man/man5/fstab.5	Sat Jun 22 03:16:01 2019	(r349286)
> @@ -216,6 +216,12 @@ then the special file is made available as a piece of 
>  space by the
>  .Xr swapon 8
>  command at the end of the system reboot procedure.
> +For swap devices, the keyword
> +.Dq trimonce
> +triggers the delivery of a
> +.Dv BIO_DELETE
> +command to the device to mark
> +all blocks as unused.
>  For vnode-backed swap spaces,
>  .Dq file
>  is supported in the