diff options
| author | Bernardo Innocenti | 2007-10-29 03:47:33 +0100 |
|---|---|---|
| committer | Karel Zak | 2008-02-19 01:05:55 +0100 |
| commit | 024e1a4f90ad98495863e57132edbadc80a3cac5 (patch) | |
| tree | d32da67d844fc3b1d3b03922f2181f8e839ef6fc /mount/lomount.c | |
| parent | tests: add "sort" to cramfs test (diff) | |
| download | kernel-qcow2-util-linux-024e1a4f90ad98495863e57132edbadc80a3cac5.tar.gz kernel-qcow2-util-linux-024e1a4f90ad98495863e57132edbadc80a3cac5.tar.xz kernel-qcow2-util-linux-024e1a4f90ad98495863e57132edbadc80a3cac5.zip | |
mount: allow auto-destruction of loop devices
This allows a flag to be set on loop devices so that when they are closed
for the last time, they'll self-destruct.
The kernel part has been submitted to lkml by David Woodhouse.
Signed-off-by: Bernardo Innocenti <bernie@codewiz.org>
Signed-off-by: Karel Zak <kzak@redhat.com>
Diffstat (limited to 'mount/lomount.c')
| -rw-r--r-- | mount/lomount.c | 34 |
1 files changed, 28 insertions, 6 deletions
diff --git a/mount/lomount.c b/mount/lomount.c index c5d03c48b..ac379c0db 100644 --- a/mount/lomount.c +++ b/mount/lomount.c @@ -609,7 +609,7 @@ digits_only(const char *s) { int set_loop(const char *device, const char *file, unsigned long long offset, - const char *encryption, int pfd, int *loopro) { + const char *encryption, int pfd, int *options) { struct loop_info64 loopinfo64; int fd, ffd, mode, i; char *pass; @@ -625,22 +625,21 @@ set_loop(const char *device, const char *file, unsigned long long offset, } } - mode = (*loopro ? O_RDONLY : O_RDWR); + mode = (*options & SETLOOP_RDONLY) ? O_RDONLY : O_RDWR; if ((ffd = open(file, mode)) < 0) { - if (!*loopro && errno == EROFS) + if (!(*options & SETLOOP_RDONLY) && errno == EROFS) ffd = open(file, mode = O_RDONLY); if (ffd < 0) { perror(file); return 1; } + *options |= SETLOOP_RDONLY; } if ((fd = open(device, mode)) < 0) { perror (device); close(ffd); return 1; } - *loopro = (mode == O_RDONLY); - memset(&loopinfo64, 0, sizeof(loopinfo64)); if (!(filename = canonicalize(file))) @@ -708,6 +707,9 @@ set_loop(const char *device, const char *file, unsigned long long offset, } close (ffd); + if (*options & SETLOOP_AUTOCLEAR) + loopinfo64.lo_flags = LO_FLAGS_AUTOCLEAR; + i = ioctl(fd, LOOP_SET_STATUS64, &loopinfo64); if (i) { struct loop_info loopinfo; @@ -716,16 +718,30 @@ set_loop(const char *device, const char *file, unsigned long long offset, i = loop_info64_to_old(&loopinfo64, &loopinfo); if (i) { errno = errsv; + *options &= ~SETLOOP_AUTOCLEAR; perror("ioctl: LOOP_SET_STATUS64"); } else { i = ioctl(fd, LOOP_SET_STATUS, &loopinfo); if (i) perror("ioctl: LOOP_SET_STATUS"); + else if (*options & SETLOOP_AUTOCLEAR) + { + i = ioctl(fd, LOOP_GET_STATUS, &loopinfo); + if (i || !(loopinfo.lo_flags & LO_FLAGS_AUTOCLEAR)) + *options &= ~SETLOOP_AUTOCLEAR; + } } memset(&loopinfo, 0, sizeof(loopinfo)); } + else if (*options & SETLOOP_AUTOCLEAR) + { + i = ioctl(fd, LOOP_GET_STATUS64, &loopinfo64); + if (i || !(loopinfo64.lo_flags & LO_FLAGS_AUTOCLEAR)) + *options &= ~SETLOOP_AUTOCLEAR; + } memset(&loopinfo64, 0, sizeof(loopinfo64)); + if (i) { ioctl (fd, LOOP_CLR_FD, 0); close (fd); @@ -733,7 +749,13 @@ set_loop(const char *device, const char *file, unsigned long long offset, free(filename); return 1; } - close (fd); + + /* + * HACK: here we're leeking a file descriptor, + * but mount is a short-lived process anyway. + */ + if (!(*options & SETLOOP_AUTOCLEAR)) + close (fd); if (verbose > 1) printf(_("set_loop(%s,%s,%llu): success\n"), |