| Message ID | 161370468470.2389661.11874247132336274370.stgit@magnolia (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
| Series | xfs_repair: set needsrepair when dirtying filesystems | expand |
On 2/18/21 9:18 PM, Darrick J. Wong wrote: > From: Darrick J. Wong <djwong@kernel.org> > > Add an error injection knob so that we can simulate system failure after > a certain number of disk writes. This knob is being added so that we > can check repair's behavior after an arbitrary number of tests. > > Set LIBXFS_DEBUG_WRITE_CRASH={ddev,logdev,rtdev}=nn in the environment > to make libxfs SIGKILL itself after nn writes to the data, log, or rt > devices. Note that this only applies to xfs_buf writes and zero_range. > > Signed-off-by: Darrick J. Wong <djwong@kernel.org> > --- > include/linux.h | 13 ++++++++++ > libxfs/init.c | 68 +++++++++++++++++++++++++++++++++++++++++++++++++--- > libxfs/libxfs_io.h | 19 +++++++++++++++ > libxfs/rdwr.c | 6 ++++- > 4 files changed, 101 insertions(+), 5 deletions(-) > > > diff --git a/include/linux.h b/include/linux.h > index 03b3278b..7bf59e07 100644 > --- a/include/linux.h > +++ b/include/linux.h > @@ -31,6 +31,8 @@ > #ifdef OVERRIDE_SYSTEM_FSXATTR > # undef fsxattr > #endif > +#include <unistd.h> > +#include <assert.h> > > static __inline__ int xfsctl(const char *path, int fd, int cmd, void *p) > { > @@ -186,6 +188,17 @@ platform_zero_range( > #define platform_zero_range(fd, s, l) (-EOPNOTSUPP) > #endif > > +/* > + * Use SIGKILL to simulate an immediate program crash, without a chance to run > + * atexit handlers. > + */ > +static inline void > +platform_crash(void) > +{ > + kill(getpid(), SIGKILL); > + assert(0); > +} > + > /* > * Check whether we have to define FS_IOC_FS[GS]ETXATTR ourselves. These > * are a copy of the definitions moved to linux/uapi/fs.h in the 4.5 kernel, > diff --git a/libxfs/init.c b/libxfs/init.c > index 8a8ce3c4..1ec83791 100644 > --- a/libxfs/init.c > +++ b/libxfs/init.c > @@ -590,7 +590,8 @@ libxfs_initialize_perag( > static struct xfs_buftarg * > libxfs_buftarg_alloc( > struct xfs_mount *mp, > - dev_t dev) > + dev_t dev, > + unsigned long write_fails) > { > struct xfs_buftarg *btp; > > @@ -603,10 +604,29 @@ libxfs_buftarg_alloc( > btp->bt_mount = mp; > btp->bt_bdev = dev; > btp->flags = 0; > + if (write_fails) { > + btp->writes_left = write_fails; > + btp->flags |= XFS_BUFTARG_INJECT_WRITE_FAIL; > + } > + pthread_mutex_init(&btp->lock, NULL); > > return btp; > } > > +enum libxfs_write_failure_nums { > + WF_DATA = 0, > + WF_LOG, > + WF_RT, > + WF_MAX_OPTS, > +}; > + > +static char *wf_opts[] = { > + [WF_DATA] = "ddev", > + [WF_LOG] = "logdev", > + [WF_RT] = "rtdev", > + [WF_MAX_OPTS] = NULL, > +}; > + > void > libxfs_buftarg_init( > struct xfs_mount *mp, > @@ -614,6 +634,46 @@ libxfs_buftarg_init( > dev_t logdev, > dev_t rtdev) > { > + char *p = getenv("LIBXFS_DEBUG_WRITE_CRASH"); > + unsigned long dfail = 0, lfail = 0, rfail = 0; > + > + /* Simulate utility crash after a certain number of writes. */ > + while (p && *p) { > + char *val; > + > + switch (getsubopt(&p, wf_opts, &val)) { > + case WF_DATA: > + if (!val) { > + fprintf(stderr, > + _("ddev write fail requires a parameter\n")); > + exit(1); > + } > + dfail = strtoul(val, NULL, 0); so if we do "LIBXFS_DEBUG_WRITE_CRASH=ddev=WHEEEEEEEE!" we get back "dfail = 0" and nothing happens and ... that's fine, this is a debug thingy. > + break; > + case WF_LOG: > + if (!val) { > + fprintf(stderr, > + _("logdev write fail requires a parameter\n")); > + exit(1); > + } > + lfail = strtoul(val, NULL, 0); > + break; > + case WF_RT: > + if (!val) { > + fprintf(stderr, > + _("rtdev write fail requires a parameter\n")); > + exit(1); > + } > + rfail = strtoul(val, NULL, 0); > + break; > + default: > + fprintf(stderr, _("unknown write fail type %s\n"), > + val); > + exit(1); although I guess we do error handling here. *shrug* don't much care, I guess. > + break; > + } > + } > + > if (mp->m_ddev_targp) { > /* should already have all buftargs initialised */ > if (mp->m_ddev_targp->bt_bdev != dev || > @@ -647,12 +707,12 @@ libxfs_buftarg_init( > return; > } > > - mp->m_ddev_targp = libxfs_buftarg_alloc(mp, dev); > + mp->m_ddev_targp = libxfs_buftarg_alloc(mp, dev, dfail); > if (!logdev || logdev == dev) > mp->m_logdev_targp = mp->m_ddev_targp; > else > - mp->m_logdev_targp = libxfs_buftarg_alloc(mp, logdev); > - mp->m_rtdev_targp = libxfs_buftarg_alloc(mp, rtdev); > + mp->m_logdev_targp = libxfs_buftarg_alloc(mp, logdev, lfail); > + mp->m_rtdev_targp = libxfs_buftarg_alloc(mp, rtdev, rfail); > } > > /* > diff --git a/libxfs/libxfs_io.h b/libxfs/libxfs_io.h > index c80e2d59..3cc4f4ee 100644 > --- a/libxfs/libxfs_io.h > +++ b/libxfs/libxfs_io.h > @@ -22,6 +22,8 @@ struct xfs_perag; > */ > struct xfs_buftarg { > struct xfs_mount *bt_mount; > + pthread_mutex_t lock; > + unsigned long writes_left; > dev_t bt_bdev; > unsigned int flags; > }; > @@ -30,6 +32,23 @@ struct xfs_buftarg { > #define XFS_BUFTARG_LOST_WRITE (1 << 0) > /* A dirty buffer failed the write verifier. */ > #define XFS_BUFTARG_CORRUPT_WRITE (1 << 1) > +/* Simulate failure after a certain number of writes. */ > +#define XFS_BUFTARG_INJECT_WRITE_FAIL (1 << 2) > + > +/* Simulate the system crashing after a certain number of writes. */ > +static inline void > +xfs_buftarg_trip_write( > + struct xfs_buftarg *btp) > +{ > + if (!(btp->flags & XFS_BUFTARG_INJECT_WRITE_FAIL)) > + return; > + > + pthread_mutex_lock(&btp->lock); > + btp->writes_left--; > + if (!btp->writes_left) > + platform_crash(); > + pthread_mutex_unlock(&btp->lock); > +} > > extern void libxfs_buftarg_init(struct xfs_mount *mp, dev_t ddev, > dev_t logdev, dev_t rtdev); > diff --git a/libxfs/rdwr.c b/libxfs/rdwr.c > index ca272387..fd456d6b 100644 > --- a/libxfs/rdwr.c > +++ b/libxfs/rdwr.c > @@ -74,8 +74,10 @@ libxfs_device_zero(struct xfs_buftarg *btp, xfs_daddr_t start, uint len) > /* try to use special zeroing methods, fall back to writes if needed */ > len_bytes = LIBXFS_BBTOOFF64(len); > error = platform_zero_range(fd, start_offset, len_bytes); > - if (!error) > + if (!error) { > + xfs_buftarg_trip_write(btp); Fine, but is there any real reason to catch this operation? *shrug* > return 0; > + } > > zsize = min(BDSTRAT_SIZE, BBTOB(len)); > if ((z = memalign(libxfs_device_alignment(), zsize)) == NULL) { > @@ -105,6 +107,7 @@ libxfs_device_zero(struct xfs_buftarg *btp, xfs_daddr_t start, uint len) > progname, __FUNCTION__); > exit(1); > } > + xfs_buftarg_trip_write(btp); I guess it's consistent with this; I wonder if we really need to trip in the zeroing code; it almost makes it more complex to figure out how many ops we want to "trip" after... OTOH I guess you want to be able to test a half-completed zeroing. Hrm. > offset += bytes; > } > free(z); > @@ -860,6 +863,7 @@ libxfs_bwrite( > } else { > bp->b_flags |= LIBXFS_B_UPTODATE; > bp->b_flags &= ~(LIBXFS_B_DIRTY | LIBXFS_B_UNCHECKED); > + xfs_buftarg_trip_write(bp->b_target); this is where I expected the hook to go, having not considered the zeroing code ;) > } > return bp->b_error; > } >
On Fri, Feb 19, 2021 at 06:51:17PM -0600, Eric Sandeen wrote: > On 2/18/21 9:18 PM, Darrick J. Wong wrote: > > From: Darrick J. Wong <djwong@kernel.org> > > > > Add an error injection knob so that we can simulate system failure after > > a certain number of disk writes. This knob is being added so that we > > can check repair's behavior after an arbitrary number of tests. > > > > Set LIBXFS_DEBUG_WRITE_CRASH={ddev,logdev,rtdev}=nn in the environment > > to make libxfs SIGKILL itself after nn writes to the data, log, or rt > > devices. Note that this only applies to xfs_buf writes and zero_range. > > > > Signed-off-by: Darrick J. Wong <djwong@kernel.org> > > --- > > include/linux.h | 13 ++++++++++ > > libxfs/init.c | 68 +++++++++++++++++++++++++++++++++++++++++++++++++--- > > libxfs/libxfs_io.h | 19 +++++++++++++++ > > libxfs/rdwr.c | 6 ++++- > > 4 files changed, 101 insertions(+), 5 deletions(-) > > > > > > diff --git a/include/linux.h b/include/linux.h > > index 03b3278b..7bf59e07 100644 > > --- a/include/linux.h > > +++ b/include/linux.h > > @@ -31,6 +31,8 @@ > > #ifdef OVERRIDE_SYSTEM_FSXATTR > > # undef fsxattr > > #endif > > +#include <unistd.h> > > +#include <assert.h> > > > > static __inline__ int xfsctl(const char *path, int fd, int cmd, void *p) > > { > > @@ -186,6 +188,17 @@ platform_zero_range( > > #define platform_zero_range(fd, s, l) (-EOPNOTSUPP) > > #endif > > > > +/* > > + * Use SIGKILL to simulate an immediate program crash, without a chance to run > > + * atexit handlers. > > + */ > > +static inline void > > +platform_crash(void) > > +{ > > + kill(getpid(), SIGKILL); > > + assert(0); > > +} > > + > > /* > > * Check whether we have to define FS_IOC_FS[GS]ETXATTR ourselves. These > > * are a copy of the definitions moved to linux/uapi/fs.h in the 4.5 kernel, > > diff --git a/libxfs/init.c b/libxfs/init.c > > index 8a8ce3c4..1ec83791 100644 > > --- a/libxfs/init.c > > +++ b/libxfs/init.c > > @@ -590,7 +590,8 @@ libxfs_initialize_perag( > > static struct xfs_buftarg * > > libxfs_buftarg_alloc( > > struct xfs_mount *mp, > > - dev_t dev) > > + dev_t dev, > > + unsigned long write_fails) > > { > > struct xfs_buftarg *btp; > > > > @@ -603,10 +604,29 @@ libxfs_buftarg_alloc( > > btp->bt_mount = mp; > > btp->bt_bdev = dev; > > btp->flags = 0; > > + if (write_fails) { > > + btp->writes_left = write_fails; > > + btp->flags |= XFS_BUFTARG_INJECT_WRITE_FAIL; > > + } > > + pthread_mutex_init(&btp->lock, NULL); > > > > return btp; > > } > > > > +enum libxfs_write_failure_nums { > > + WF_DATA = 0, > > + WF_LOG, > > + WF_RT, > > + WF_MAX_OPTS, > > +}; > > + > > +static char *wf_opts[] = { > > + [WF_DATA] = "ddev", > > + [WF_LOG] = "logdev", > > + [WF_RT] = "rtdev", > > + [WF_MAX_OPTS] = NULL, > > +}; > > + > > void > > libxfs_buftarg_init( > > struct xfs_mount *mp, > > @@ -614,6 +634,46 @@ libxfs_buftarg_init( > > dev_t logdev, > > dev_t rtdev) > > { > > + char *p = getenv("LIBXFS_DEBUG_WRITE_CRASH"); > > + unsigned long dfail = 0, lfail = 0, rfail = 0; > > + > > + /* Simulate utility crash after a certain number of writes. */ > > + while (p && *p) { > > + char *val; > > + > > + switch (getsubopt(&p, wf_opts, &val)) { > > + case WF_DATA: > > + if (!val) { > > + fprintf(stderr, > > + _("ddev write fail requires a parameter\n")); > > + exit(1); > > + } > > + dfail = strtoul(val, NULL, 0); > > so if we do "LIBXFS_DEBUG_WRITE_CRASH=ddev=WHEEEEEEEE!" we get back > "dfail = 0" and nothing happens and ... that's fine, this is a debug > thingy. Yep. If you use the knob, you're expected to use it correctly. > > + break; > > + case WF_LOG: > > + if (!val) { > > + fprintf(stderr, > > + _("logdev write fail requires a parameter\n")); > > + exit(1); > > + } > > + lfail = strtoul(val, NULL, 0); > > + break; > > + case WF_RT: > > + if (!val) { > > + fprintf(stderr, > > + _("rtdev write fail requires a parameter\n")); > > + exit(1); > > + } > > + rfail = strtoul(val, NULL, 0); > > + break; > > + default: > > + fprintf(stderr, _("unknown write fail type %s\n"), > > + val); > > + exit(1); > > although I guess we do error handling here. *shrug* don't much care, > I guess. Just in case we add new debug knobs in the future and fstests need a way to detect them. > > + break; > > + } > > + } > > + > > if (mp->m_ddev_targp) { > > /* should already have all buftargs initialised */ > > if (mp->m_ddev_targp->bt_bdev != dev || > > @@ -647,12 +707,12 @@ libxfs_buftarg_init( > > return; > > } > > > > - mp->m_ddev_targp = libxfs_buftarg_alloc(mp, dev); > > + mp->m_ddev_targp = libxfs_buftarg_alloc(mp, dev, dfail); > > if (!logdev || logdev == dev) > > mp->m_logdev_targp = mp->m_ddev_targp; > > else > > - mp->m_logdev_targp = libxfs_buftarg_alloc(mp, logdev); > > - mp->m_rtdev_targp = libxfs_buftarg_alloc(mp, rtdev); > > + mp->m_logdev_targp = libxfs_buftarg_alloc(mp, logdev, lfail); > > + mp->m_rtdev_targp = libxfs_buftarg_alloc(mp, rtdev, rfail); > > } > > > > /* > > diff --git a/libxfs/libxfs_io.h b/libxfs/libxfs_io.h > > index c80e2d59..3cc4f4ee 100644 > > --- a/libxfs/libxfs_io.h > > +++ b/libxfs/libxfs_io.h > > @@ -22,6 +22,8 @@ struct xfs_perag; > > */ > > struct xfs_buftarg { > > struct xfs_mount *bt_mount; > > + pthread_mutex_t lock; > > + unsigned long writes_left; > > dev_t bt_bdev; > > unsigned int flags; > > }; > > @@ -30,6 +32,23 @@ struct xfs_buftarg { > > #define XFS_BUFTARG_LOST_WRITE (1 << 0) > > /* A dirty buffer failed the write verifier. */ > > #define XFS_BUFTARG_CORRUPT_WRITE (1 << 1) > > +/* Simulate failure after a certain number of writes. */ > > +#define XFS_BUFTARG_INJECT_WRITE_FAIL (1 << 2) > > + > > +/* Simulate the system crashing after a certain number of writes. */ > > +static inline void > > +xfs_buftarg_trip_write( > > + struct xfs_buftarg *btp) > > +{ > > + if (!(btp->flags & XFS_BUFTARG_INJECT_WRITE_FAIL)) > > + return; > > + > > + pthread_mutex_lock(&btp->lock); > > + btp->writes_left--; > > + if (!btp->writes_left) > > + platform_crash(); > > + pthread_mutex_unlock(&btp->lock); > > +} > > > > extern void libxfs_buftarg_init(struct xfs_mount *mp, dev_t ddev, > > dev_t logdev, dev_t rtdev); > > diff --git a/libxfs/rdwr.c b/libxfs/rdwr.c > > index ca272387..fd456d6b 100644 > > --- a/libxfs/rdwr.c > > +++ b/libxfs/rdwr.c > > @@ -74,8 +74,10 @@ libxfs_device_zero(struct xfs_buftarg *btp, xfs_daddr_t start, uint len) > > /* try to use special zeroing methods, fall back to writes if needed */ > > len_bytes = LIBXFS_BBTOOFF64(len); > > error = platform_zero_range(fd, start_offset, len_bytes); > > - if (!error) > > + if (!error) { > > + xfs_buftarg_trip_write(btp); > > Fine, but is there any real reason to catch this operation? *shrug* > > > return 0; > > + } > > > > zsize = min(BDSTRAT_SIZE, BBTOB(len)); > > if ((z = memalign(libxfs_device_alignment(), zsize)) == NULL) { > > @@ -105,6 +107,7 @@ libxfs_device_zero(struct xfs_buftarg *btp, xfs_daddr_t start, uint len) > > progname, __FUNCTION__); > > exit(1); > > } > > + xfs_buftarg_trip_write(btp); > > I guess it's consistent with this; I wonder if we really need to trip > in the zeroing code; it almost makes it more complex to figure out how > many ops we want to "trip" after... OTOH I guess you want to be able > to test a half-completed zeroing. Hrm. Well yes, since I was asked to write a more generic write error injection mechanism, I decided I might as well use it for /all/ types of writes, even if the "write" is a fancy zeroing op. :) --D > > > offset += bytes; > > } > > free(z); > > @@ -860,6 +863,7 @@ libxfs_bwrite( > > } else { > > bp->b_flags |= LIBXFS_B_UPTODATE; > > bp->b_flags &= ~(LIBXFS_B_DIRTY | LIBXFS_B_UNCHECKED); > > + xfs_buftarg_trip_write(bp->b_target); > > this is where I expected the hook to go, having not considered the zeroing > code ;) > > > } > > return bp->b_error; > > } > >
On Thu, Feb 18, 2021 at 07:18:04PM -0800, Darrick J. Wong wrote: > From: Darrick J. Wong <djwong@kernel.org> > > Add an error injection knob so that we can simulate system failure after > a certain number of disk writes. This knob is being added so that we > can check repair's behavior after an arbitrary number of tests. > > Set LIBXFS_DEBUG_WRITE_CRASH={ddev,logdev,rtdev}=nn in the environment > to make libxfs SIGKILL itself after nn writes to the data, log, or rt > devices. Note that this only applies to xfs_buf writes and zero_range. > > Signed-off-by: Darrick J. Wong <djwong@kernel.org> > --- Modulo Eric's feedback: Reviewed-by: Brian Foster <bfoster@redhat.com> > include/linux.h | 13 ++++++++++ > libxfs/init.c | 68 +++++++++++++++++++++++++++++++++++++++++++++++++--- > libxfs/libxfs_io.h | 19 +++++++++++++++ > libxfs/rdwr.c | 6 ++++- > 4 files changed, 101 insertions(+), 5 deletions(-) > > > diff --git a/include/linux.h b/include/linux.h > index 03b3278b..7bf59e07 100644 > --- a/include/linux.h > +++ b/include/linux.h > @@ -31,6 +31,8 @@ > #ifdef OVERRIDE_SYSTEM_FSXATTR > # undef fsxattr > #endif > +#include <unistd.h> > +#include <assert.h> > > static __inline__ int xfsctl(const char *path, int fd, int cmd, void *p) > { > @@ -186,6 +188,17 @@ platform_zero_range( > #define platform_zero_range(fd, s, l) (-EOPNOTSUPP) > #endif > > +/* > + * Use SIGKILL to simulate an immediate program crash, without a chance to run > + * atexit handlers. > + */ > +static inline void > +platform_crash(void) > +{ > + kill(getpid(), SIGKILL); > + assert(0); > +} > + > /* > * Check whether we have to define FS_IOC_FS[GS]ETXATTR ourselves. These > * are a copy of the definitions moved to linux/uapi/fs.h in the 4.5 kernel, > diff --git a/libxfs/init.c b/libxfs/init.c > index 8a8ce3c4..1ec83791 100644 > --- a/libxfs/init.c > +++ b/libxfs/init.c > @@ -590,7 +590,8 @@ libxfs_initialize_perag( > static struct xfs_buftarg * > libxfs_buftarg_alloc( > struct xfs_mount *mp, > - dev_t dev) > + dev_t dev, > + unsigned long write_fails) > { > struct xfs_buftarg *btp; > > @@ -603,10 +604,29 @@ libxfs_buftarg_alloc( > btp->bt_mount = mp; > btp->bt_bdev = dev; > btp->flags = 0; > + if (write_fails) { > + btp->writes_left = write_fails; > + btp->flags |= XFS_BUFTARG_INJECT_WRITE_FAIL; > + } > + pthread_mutex_init(&btp->lock, NULL); > > return btp; > } > > +enum libxfs_write_failure_nums { > + WF_DATA = 0, > + WF_LOG, > + WF_RT, > + WF_MAX_OPTS, > +}; > + > +static char *wf_opts[] = { > + [WF_DATA] = "ddev", > + [WF_LOG] = "logdev", > + [WF_RT] = "rtdev", > + [WF_MAX_OPTS] = NULL, > +}; > + > void > libxfs_buftarg_init( > struct xfs_mount *mp, > @@ -614,6 +634,46 @@ libxfs_buftarg_init( > dev_t logdev, > dev_t rtdev) > { > + char *p = getenv("LIBXFS_DEBUG_WRITE_CRASH"); > + unsigned long dfail = 0, lfail = 0, rfail = 0; > + > + /* Simulate utility crash after a certain number of writes. */ > + while (p && *p) { > + char *val; > + > + switch (getsubopt(&p, wf_opts, &val)) { > + case WF_DATA: > + if (!val) { > + fprintf(stderr, > + _("ddev write fail requires a parameter\n")); > + exit(1); > + } > + dfail = strtoul(val, NULL, 0); > + break; > + case WF_LOG: > + if (!val) { > + fprintf(stderr, > + _("logdev write fail requires a parameter\n")); > + exit(1); > + } > + lfail = strtoul(val, NULL, 0); > + break; > + case WF_RT: > + if (!val) { > + fprintf(stderr, > + _("rtdev write fail requires a parameter\n")); > + exit(1); > + } > + rfail = strtoul(val, NULL, 0); > + break; > + default: > + fprintf(stderr, _("unknown write fail type %s\n"), > + val); > + exit(1); > + break; > + } > + } > + > if (mp->m_ddev_targp) { > /* should already have all buftargs initialised */ > if (mp->m_ddev_targp->bt_bdev != dev || > @@ -647,12 +707,12 @@ libxfs_buftarg_init( > return; > } > > - mp->m_ddev_targp = libxfs_buftarg_alloc(mp, dev); > + mp->m_ddev_targp = libxfs_buftarg_alloc(mp, dev, dfail); > if (!logdev || logdev == dev) > mp->m_logdev_targp = mp->m_ddev_targp; > else > - mp->m_logdev_targp = libxfs_buftarg_alloc(mp, logdev); > - mp->m_rtdev_targp = libxfs_buftarg_alloc(mp, rtdev); > + mp->m_logdev_targp = libxfs_buftarg_alloc(mp, logdev, lfail); > + mp->m_rtdev_targp = libxfs_buftarg_alloc(mp, rtdev, rfail); > } > > /* > diff --git a/libxfs/libxfs_io.h b/libxfs/libxfs_io.h > index c80e2d59..3cc4f4ee 100644 > --- a/libxfs/libxfs_io.h > +++ b/libxfs/libxfs_io.h > @@ -22,6 +22,8 @@ struct xfs_perag; > */ > struct xfs_buftarg { > struct xfs_mount *bt_mount; > + pthread_mutex_t lock; > + unsigned long writes_left; > dev_t bt_bdev; > unsigned int flags; > }; > @@ -30,6 +32,23 @@ struct xfs_buftarg { > #define XFS_BUFTARG_LOST_WRITE (1 << 0) > /* A dirty buffer failed the write verifier. */ > #define XFS_BUFTARG_CORRUPT_WRITE (1 << 1) > +/* Simulate failure after a certain number of writes. */ > +#define XFS_BUFTARG_INJECT_WRITE_FAIL (1 << 2) > + > +/* Simulate the system crashing after a certain number of writes. */ > +static inline void > +xfs_buftarg_trip_write( > + struct xfs_buftarg *btp) > +{ > + if (!(btp->flags & XFS_BUFTARG_INJECT_WRITE_FAIL)) > + return; > + > + pthread_mutex_lock(&btp->lock); > + btp->writes_left--; > + if (!btp->writes_left) > + platform_crash(); > + pthread_mutex_unlock(&btp->lock); > +} > > extern void libxfs_buftarg_init(struct xfs_mount *mp, dev_t ddev, > dev_t logdev, dev_t rtdev); > diff --git a/libxfs/rdwr.c b/libxfs/rdwr.c > index ca272387..fd456d6b 100644 > --- a/libxfs/rdwr.c > +++ b/libxfs/rdwr.c > @@ -74,8 +74,10 @@ libxfs_device_zero(struct xfs_buftarg *btp, xfs_daddr_t start, uint len) > /* try to use special zeroing methods, fall back to writes if needed */ > len_bytes = LIBXFS_BBTOOFF64(len); > error = platform_zero_range(fd, start_offset, len_bytes); > - if (!error) > + if (!error) { > + xfs_buftarg_trip_write(btp); > return 0; > + } > > zsize = min(BDSTRAT_SIZE, BBTOB(len)); > if ((z = memalign(libxfs_device_alignment(), zsize)) == NULL) { > @@ -105,6 +107,7 @@ libxfs_device_zero(struct xfs_buftarg *btp, xfs_daddr_t start, uint len) > progname, __FUNCTION__); > exit(1); > } > + xfs_buftarg_trip_write(btp); > offset += bytes; > } > free(z); > @@ -860,6 +863,7 @@ libxfs_bwrite( > } else { > bp->b_flags |= LIBXFS_B_UPTODATE; > bp->b_flags &= ~(LIBXFS_B_DIRTY | LIBXFS_B_UNCHECKED); > + xfs_buftarg_trip_write(bp->b_target); > } > return bp->b_error; > } >
diff --git a/include/linux.h b/include/linux.h index 03b3278b..7bf59e07 100644 --- a/include/linux.h +++ b/include/linux.h @@ -31,6 +31,8 @@ #ifdef OVERRIDE_SYSTEM_FSXATTR # undef fsxattr #endif +#include <unistd.h> +#include <assert.h> static __inline__ int xfsctl(const char *path, int fd, int cmd, void *p) { @@ -186,6 +188,17 @@ platform_zero_range( #define platform_zero_range(fd, s, l) (-EOPNOTSUPP) #endif +/* + * Use SIGKILL to simulate an immediate program crash, without a chance to run + * atexit handlers. + */ +static inline void +platform_crash(void) +{ + kill(getpid(), SIGKILL); + assert(0); +} + /* * Check whether we have to define FS_IOC_FS[GS]ETXATTR ourselves. These * are a copy of the definitions moved to linux/uapi/fs.h in the 4.5 kernel, diff --git a/libxfs/init.c b/libxfs/init.c index 8a8ce3c4..1ec83791 100644 --- a/libxfs/init.c +++ b/libxfs/init.c @@ -590,7 +590,8 @@ libxfs_initialize_perag( static struct xfs_buftarg * libxfs_buftarg_alloc( struct xfs_mount *mp, - dev_t dev) + dev_t dev, + unsigned long write_fails) { struct xfs_buftarg *btp; @@ -603,10 +604,29 @@ libxfs_buftarg_alloc( btp->bt_mount = mp; btp->bt_bdev = dev; btp->flags = 0; + if (write_fails) { + btp->writes_left = write_fails; + btp->flags |= XFS_BUFTARG_INJECT_WRITE_FAIL; + } + pthread_mutex_init(&btp->lock, NULL); return btp; } +enum libxfs_write_failure_nums { + WF_DATA = 0, + WF_LOG, + WF_RT, + WF_MAX_OPTS, +}; + +static char *wf_opts[] = { + [WF_DATA] = "ddev", + [WF_LOG] = "logdev", + [WF_RT] = "rtdev", + [WF_MAX_OPTS] = NULL, +}; + void libxfs_buftarg_init( struct xfs_mount *mp, @@ -614,6 +634,46 @@ libxfs_buftarg_init( dev_t logdev, dev_t rtdev) { + char *p = getenv("LIBXFS_DEBUG_WRITE_CRASH"); + unsigned long dfail = 0, lfail = 0, rfail = 0; + + /* Simulate utility crash after a certain number of writes. */ + while (p && *p) { + char *val; + + switch (getsubopt(&p, wf_opts, &val)) { + case WF_DATA: + if (!val) { + fprintf(stderr, + _("ddev write fail requires a parameter\n")); + exit(1); + } + dfail = strtoul(val, NULL, 0); + break; + case WF_LOG: + if (!val) { + fprintf(stderr, + _("logdev write fail requires a parameter\n")); + exit(1); + } + lfail = strtoul(val, NULL, 0); + break; + case WF_RT: + if (!val) { + fprintf(stderr, + _("rtdev write fail requires a parameter\n")); + exit(1); + } + rfail = strtoul(val, NULL, 0); + break; + default: + fprintf(stderr, _("unknown write fail type %s\n"), + val); + exit(1); + break; + } + } + if (mp->m_ddev_targp) { /* should already have all buftargs initialised */ if (mp->m_ddev_targp->bt_bdev != dev || @@ -647,12 +707,12 @@ libxfs_buftarg_init( return; } - mp->m_ddev_targp = libxfs_buftarg_alloc(mp, dev); + mp->m_ddev_targp = libxfs_buftarg_alloc(mp, dev, dfail); if (!logdev || logdev == dev) mp->m_logdev_targp = mp->m_ddev_targp; else - mp->m_logdev_targp = libxfs_buftarg_alloc(mp, logdev); - mp->m_rtdev_targp = libxfs_buftarg_alloc(mp, rtdev); + mp->m_logdev_targp = libxfs_buftarg_alloc(mp, logdev, lfail); + mp->m_rtdev_targp = libxfs_buftarg_alloc(mp, rtdev, rfail); } /* diff --git a/libxfs/libxfs_io.h b/libxfs/libxfs_io.h index c80e2d59..3cc4f4ee 100644 --- a/libxfs/libxfs_io.h +++ b/libxfs/libxfs_io.h @@ -22,6 +22,8 @@ struct xfs_perag; */ struct xfs_buftarg { struct xfs_mount *bt_mount; + pthread_mutex_t lock; + unsigned long writes_left; dev_t bt_bdev; unsigned int flags; }; @@ -30,6 +32,23 @@ struct xfs_buftarg { #define XFS_BUFTARG_LOST_WRITE (1 << 0) /* A dirty buffer failed the write verifier. */ #define XFS_BUFTARG_CORRUPT_WRITE (1 << 1) +/* Simulate failure after a certain number of writes. */ +#define XFS_BUFTARG_INJECT_WRITE_FAIL (1 << 2) + +/* Simulate the system crashing after a certain number of writes. */ +static inline void +xfs_buftarg_trip_write( + struct xfs_buftarg *btp) +{ + if (!(btp->flags & XFS_BUFTARG_INJECT_WRITE_FAIL)) + return; + + pthread_mutex_lock(&btp->lock); + btp->writes_left--; + if (!btp->writes_left) + platform_crash(); + pthread_mutex_unlock(&btp->lock); +} extern void libxfs_buftarg_init(struct xfs_mount *mp, dev_t ddev, dev_t logdev, dev_t rtdev); diff --git a/libxfs/rdwr.c b/libxfs/rdwr.c index ca272387..fd456d6b 100644 --- a/libxfs/rdwr.c +++ b/libxfs/rdwr.c @@ -74,8 +74,10 @@ libxfs_device_zero(struct xfs_buftarg *btp, xfs_daddr_t start, uint len) /* try to use special zeroing methods, fall back to writes if needed */ len_bytes = LIBXFS_BBTOOFF64(len); error = platform_zero_range(fd, start_offset, len_bytes); - if (!error) + if (!error) { + xfs_buftarg_trip_write(btp); return 0; + } zsize = min(BDSTRAT_SIZE, BBTOB(len)); if ((z = memalign(libxfs_device_alignment(), zsize)) == NULL) { @@ -105,6 +107,7 @@ libxfs_device_zero(struct xfs_buftarg *btp, xfs_daddr_t start, uint len) progname, __FUNCTION__); exit(1); } + xfs_buftarg_trip_write(btp); offset += bytes; } free(z); @@ -860,6 +863,7 @@ libxfs_bwrite( } else { bp->b_flags |= LIBXFS_B_UPTODATE; bp->b_flags &= ~(LIBXFS_B_DIRTY | LIBXFS_B_UNCHECKED); + xfs_buftarg_trip_write(bp->b_target); } return bp->b_error; }