| Message ID | 20220706143822.30182-9-mwilck@suse.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Delegated to: | christophe varoqui |
| Headers | show |
| Series | multipath: fixes for sysfs accessors | expand |
On Wed, Jul 06, 2022 at 04:38:16PM +0200, mwilck@suse.com wrote: > From: Martin Wilck <mwilck@suse.com> > > sysfs_attr_set_value() returned 0 if not all requested bytes were written. > Change this to return the number of bytes written. Error checking is now > somewhat more involved; provide a helper macro fo it. > > Signed-off-by: Martin Wilck <mwilck@suse.com> > --- > libmultipath/configure.c | 10 ++++-- > libmultipath/discovery.c | 70 ++++++++++++++++++++++++++-------------- > libmultipath/sysfs.c | 6 ++-- > libmultipath/sysfs.h | 10 ++++++ > 4 files changed, 64 insertions(+), 32 deletions(-) > > diff --git a/libmultipath/configure.c b/libmultipath/configure.c > index 467bbaa..0607dba 100644 > --- a/libmultipath/configure.c > +++ b/libmultipath/configure.c > @@ -568,6 +568,7 @@ sysfs_set_max_sectors_kb(struct multipath *mpp, int is_reload) > struct pathgroup * pgp; > struct path *pp; > char buff[11]; > + ssize_t len; > int i, j, ret, err = 0; > struct udev_device *udd; > int max_sectors_kb; > @@ -600,14 +601,17 @@ sysfs_set_max_sectors_kb(struct multipath *mpp, int is_reload) > } > } > snprintf(buff, 11, "%d", max_sectors_kb); > + len = strlen(buff); > > vector_foreach_slot (mpp->pg, pgp, i) { > vector_foreach_slot(pgp->paths, pp, j) { > ret = sysfs_attr_set_value(pp->udev, > "queue/max_sectors_kb", > - buff, strlen(buff)); > - if (ret < 0) { > - condlog(1, "failed setting max_sectors_kb on %s : %s", pp->dev, strerror(-ret)); > + buff, len); > + if (ret != len) { > + log_sysfs_attr_set_value(1, ret, > + "failed setting max_sectors_kb on %s", > + pp->dev); > err = 1; > } > } > diff --git a/libmultipath/discovery.c b/libmultipath/discovery.c > index 54b1caf..1137629 100644 > --- a/libmultipath/discovery.c > +++ b/libmultipath/discovery.c > @@ -603,8 +603,10 @@ sysfs_set_eh_deadline(struct path *pp) > * not all scsi drivers support setting eh_deadline, so failing > * is totally reasonable > */ > - if (ret <= 0) > - condlog(3, "%s: failed to set eh_deadline to %s, error %d", udev_device_get_sysname(hostdev), value, -ret); > + if (ret != len + 1) I know that this was originally my error, but I don't see any reason why we should check (or write) the NULL byte here. I can fix this is in a separate patch, or you can fix it along with my other issue for this patch. > + log_sysfs_attr_set_value(3, ret, > + "%s: failed to set eh_deadline to %s", > + udev_device_get_sysname(hostdev), value); > > udev_device_unref(hostdev); > return (ret <= 0); > @@ -667,19 +669,22 @@ sysfs_set_rport_tmo(struct multipath *mpp, struct path *pp) > pp->fast_io_fail != MP_FAST_IO_FAIL_OFF) { > /* Check if we need to temporarily increase dev_loss_tmo */ > if ((unsigned int)pp->fast_io_fail >= tmo) { > + ssize_t len; > + > /* Increase dev_loss_tmo temporarily */ > snprintf(value, sizeof(value), "%u", > (unsigned int)pp->fast_io_fail + 1); > + len = strlen(value); > ret = sysfs_attr_set_value(rport_dev, "dev_loss_tmo", > - value, strlen(value)); > - if (ret <= 0) { > + value, len); > + if (ret != len) { > if (ret == -EBUSY) > condlog(3, "%s: rport blocked", > rport_id); > else > - condlog(0, "%s: failed to set " > - "dev_loss_tmo to %s, error %d", > - rport_id, value, -ret); > + log_sysfs_attr_set_value(0, ret, > + "%s: failed to set dev_loss_tmo to %s", > + rport_id, value); > goto out; > } > } > @@ -691,32 +696,39 @@ sysfs_set_rport_tmo(struct multipath *mpp, struct path *pp) > pp->dev_loss = DEFAULT_DEV_LOSS_TMO; > } > if (pp->fast_io_fail != MP_FAST_IO_FAIL_UNSET) { > + ssize_t len; > + > if (pp->fast_io_fail == MP_FAST_IO_FAIL_OFF) > sprintf(value, "off"); > else if (pp->fast_io_fail == MP_FAST_IO_FAIL_ZERO) > sprintf(value, "0"); > else > snprintf(value, 16, "%u", pp->fast_io_fail); > + len = strlen(value); > ret = sysfs_attr_set_value(rport_dev, "fast_io_fail_tmo", > - value, strlen(value)); > - if (ret <= 0) { > + value, len); > + if (ret != len) { > if (ret == -EBUSY) > condlog(3, "%s: rport blocked", rport_id); > else > - condlog(0, "%s: failed to set fast_io_fail_tmo to %s, error %d", > - rport_id, value, -ret); > + log_sysfs_attr_set_value(0, ret, > + "%s: failed to set fast_io_fail_tmo to %s", > + rport_id, value); > } > } > if (pp->dev_loss != DEV_LOSS_TMO_UNSET) { > + ssize_t len; > + > snprintf(value, 16, "%u", pp->dev_loss); > - ret = sysfs_attr_set_value(rport_dev, "dev_loss_tmo", > - value, strlen(value)); > + len = strlen(value); > + ret = sysfs_attr_set_value(rport_dev, "dev_loss_tmo", value, len); > if (ret <= 0) { This check should be (ret != len) -Ben > if (ret == -EBUSY) > condlog(3, "%s: rport blocked", rport_id); > else > - condlog(0, "%s: failed to set dev_loss_tmo to %s, error %d", > - rport_id, value, -ret); > + log_sysfs_attr_set_value(0, ret, > + "%s: failed to set dev_loss_tmo to %s", > + rport_id, value); > } > } > out: > @@ -754,12 +766,16 @@ sysfs_set_session_tmo(struct path *pp) > condlog(3, "%s: can't set fast_io_fail_tmo to '0'" > "on iSCSI", pp->dev); > } else { > + ssize_t len, ret; > + > snprintf(value, 11, "%u", pp->fast_io_fail); > - if (sysfs_attr_set_value(session_dev, "recovery_tmo", > - value, strlen(value)) <= 0) { > - condlog(3, "%s: Failed to set recovery_tmo, " > - " error %d", pp->dev, errno); > - } > + len = strlen(value); > + ret = sysfs_attr_set_value(session_dev, "recovery_tmo", > + value, len); > + if (ret != len) > + log_sysfs_attr_set_value(3, ret, > + "%s: Failed to set recovery_tmo to %s", > + pp->dev, value); > } > } > udev_device_unref(session_dev); > @@ -802,12 +818,16 @@ sysfs_set_nexus_loss_tmo(struct path *pp) > pp->sg_id.channel, pp->sg_id.scsi_id, end_dev_id); > > if (pp->dev_loss != DEV_LOSS_TMO_UNSET) { > + ssize_t len, ret; > + > snprintf(value, 11, "%u", pp->dev_loss); > - if (sysfs_attr_set_value(sas_dev, "I_T_nexus_loss_timeout", > - value, strlen(value)) <= 0) > - condlog(3, "%s: failed to update " > - "I_T Nexus loss timeout, error %d", > - pp->dev, errno); > + len = strlen(value); > + ret = sysfs_attr_set_value(sas_dev, "I_T_nexus_loss_timeout", > + value, len); > + if (ret != len) > + log_sysfs_attr_set_value(3, ret, > + "%s: failed to update I_T Nexus loss timeout", > + pp->dev); > } > udev_device_unref(sas_dev); > return; > diff --git a/libmultipath/sysfs.c b/libmultipath/sysfs.c > index 125f1c2..9c84af7 100644 > --- a/libmultipath/sysfs.c > +++ b/libmultipath/sysfs.c > @@ -134,7 +134,7 @@ ssize_t sysfs_attr_set_value(struct udev_device *dev, const char *attr_name, > /* write attribute value */ > fd = open(devpath, O_WRONLY); > if (fd < 0) { > - condlog(2, "%s: attribute '%s' can not be opened: %s", > + condlog(3, "%s: attribute '%s' can not be opened: %s", > __func__, devpath, strerror(errno)); > return -errno; > } > @@ -144,11 +144,9 @@ ssize_t sysfs_attr_set_value(struct udev_device *dev, const char *attr_name, > size = -errno; > condlog(3, "%s: write to %s failed: %s", __func__, > devpath, strerror(errno)); > - } else if (size < (ssize_t)value_len) { > + } else if (size < (ssize_t)value_len) > condlog(3, "%s: underflow writing %zu bytes to %s. Wrote %zd bytes", > __func__, value_len, devpath, size); > - size = 0; > - } > > close(fd); > return size; > diff --git a/libmultipath/sysfs.h b/libmultipath/sysfs.h > index cdc84e4..799f68e 100644 > --- a/libmultipath/sysfs.h > +++ b/libmultipath/sysfs.h > @@ -5,6 +5,7 @@ > #ifndef _LIBMULTIPATH_SYSFS_H > #define _LIBMULTIPATH_SYSFS_H > #include <stdbool.h> > +#include "strbuf.h" > > ssize_t sysfs_attr_set_value(struct udev_device *dev, const char *attr_name, > const char * value, size_t value_len); > @@ -25,6 +26,15 @@ ssize_t sysfs_bin_attr_get_value(struct udev_device *dev, const char *attr_name, > sysfs_attr_value_ok(__rc, __l); \ > }) > > +#define log_sysfs_attr_set_value(prio, rc, fmt, __args...) \ > +do { \ > + STRBUF_ON_STACK(__buf); \ > + if (print_strbuf(&__buf, fmt, ##__args) >= 0 && \ > + print_strbuf(&__buf, ": %s", rc < 0 ? strerror(-rc) : \ > + "write underflow") >= 0) \ > + condlog(prio, "%s", get_strbuf_str(&__buf)); \ > +} while(0) > + > int sysfs_get_size (struct path *pp, unsigned long long * size); > int sysfs_check_holders(char * check_devt, char * new_devt); > bool sysfs_is_multipathed(struct path *pp, bool set_wwid); > -- > 2.36.1 -- dm-devel mailing list dm-devel@redhat.com https://listman.redhat.com/mailman/listinfo/dm-devel
diff --git a/libmultipath/configure.c b/libmultipath/configure.c index 467bbaa..0607dba 100644 --- a/libmultipath/configure.c +++ b/libmultipath/configure.c @@ -568,6 +568,7 @@ sysfs_set_max_sectors_kb(struct multipath *mpp, int is_reload) struct pathgroup * pgp; struct path *pp; char buff[11]; + ssize_t len; int i, j, ret, err = 0; struct udev_device *udd; int max_sectors_kb; @@ -600,14 +601,17 @@ sysfs_set_max_sectors_kb(struct multipath *mpp, int is_reload) } } snprintf(buff, 11, "%d", max_sectors_kb); + len = strlen(buff); vector_foreach_slot (mpp->pg, pgp, i) { vector_foreach_slot(pgp->paths, pp, j) { ret = sysfs_attr_set_value(pp->udev, "queue/max_sectors_kb", - buff, strlen(buff)); - if (ret < 0) { - condlog(1, "failed setting max_sectors_kb on %s : %s", pp->dev, strerror(-ret)); + buff, len); + if (ret != len) { + log_sysfs_attr_set_value(1, ret, + "failed setting max_sectors_kb on %s", + pp->dev); err = 1; } } diff --git a/libmultipath/discovery.c b/libmultipath/discovery.c index 54b1caf..1137629 100644 --- a/libmultipath/discovery.c +++ b/libmultipath/discovery.c @@ -603,8 +603,10 @@ sysfs_set_eh_deadline(struct path *pp) * not all scsi drivers support setting eh_deadline, so failing * is totally reasonable */ - if (ret <= 0) - condlog(3, "%s: failed to set eh_deadline to %s, error %d", udev_device_get_sysname(hostdev), value, -ret); + if (ret != len + 1) + log_sysfs_attr_set_value(3, ret, + "%s: failed to set eh_deadline to %s", + udev_device_get_sysname(hostdev), value); udev_device_unref(hostdev); return (ret <= 0); @@ -667,19 +669,22 @@ sysfs_set_rport_tmo(struct multipath *mpp, struct path *pp) pp->fast_io_fail != MP_FAST_IO_FAIL_OFF) { /* Check if we need to temporarily increase dev_loss_tmo */ if ((unsigned int)pp->fast_io_fail >= tmo) { + ssize_t len; + /* Increase dev_loss_tmo temporarily */ snprintf(value, sizeof(value), "%u", (unsigned int)pp->fast_io_fail + 1); + len = strlen(value); ret = sysfs_attr_set_value(rport_dev, "dev_loss_tmo", - value, strlen(value)); - if (ret <= 0) { + value, len); + if (ret != len) { if (ret == -EBUSY) condlog(3, "%s: rport blocked", rport_id); else - condlog(0, "%s: failed to set " - "dev_loss_tmo to %s, error %d", - rport_id, value, -ret); + log_sysfs_attr_set_value(0, ret, + "%s: failed to set dev_loss_tmo to %s", + rport_id, value); goto out; } } @@ -691,32 +696,39 @@ sysfs_set_rport_tmo(struct multipath *mpp, struct path *pp) pp->dev_loss = DEFAULT_DEV_LOSS_TMO; } if (pp->fast_io_fail != MP_FAST_IO_FAIL_UNSET) { + ssize_t len; + if (pp->fast_io_fail == MP_FAST_IO_FAIL_OFF) sprintf(value, "off"); else if (pp->fast_io_fail == MP_FAST_IO_FAIL_ZERO) sprintf(value, "0"); else snprintf(value, 16, "%u", pp->fast_io_fail); + len = strlen(value); ret = sysfs_attr_set_value(rport_dev, "fast_io_fail_tmo", - value, strlen(value)); - if (ret <= 0) { + value, len); + if (ret != len) { if (ret == -EBUSY) condlog(3, "%s: rport blocked", rport_id); else - condlog(0, "%s: failed to set fast_io_fail_tmo to %s, error %d", - rport_id, value, -ret); + log_sysfs_attr_set_value(0, ret, + "%s: failed to set fast_io_fail_tmo to %s", + rport_id, value); } } if (pp->dev_loss != DEV_LOSS_TMO_UNSET) { + ssize_t len; + snprintf(value, 16, "%u", pp->dev_loss); - ret = sysfs_attr_set_value(rport_dev, "dev_loss_tmo", - value, strlen(value)); + len = strlen(value); + ret = sysfs_attr_set_value(rport_dev, "dev_loss_tmo", value, len); if (ret <= 0) { if (ret == -EBUSY) condlog(3, "%s: rport blocked", rport_id); else - condlog(0, "%s: failed to set dev_loss_tmo to %s, error %d", - rport_id, value, -ret); + log_sysfs_attr_set_value(0, ret, + "%s: failed to set dev_loss_tmo to %s", + rport_id, value); } } out: @@ -754,12 +766,16 @@ sysfs_set_session_tmo(struct path *pp) condlog(3, "%s: can't set fast_io_fail_tmo to '0'" "on iSCSI", pp->dev); } else { + ssize_t len, ret; + snprintf(value, 11, "%u", pp->fast_io_fail); - if (sysfs_attr_set_value(session_dev, "recovery_tmo", - value, strlen(value)) <= 0) { - condlog(3, "%s: Failed to set recovery_tmo, " - " error %d", pp->dev, errno); - } + len = strlen(value); + ret = sysfs_attr_set_value(session_dev, "recovery_tmo", + value, len); + if (ret != len) + log_sysfs_attr_set_value(3, ret, + "%s: Failed to set recovery_tmo to %s", + pp->dev, value); } } udev_device_unref(session_dev); @@ -802,12 +818,16 @@ sysfs_set_nexus_loss_tmo(struct path *pp) pp->sg_id.channel, pp->sg_id.scsi_id, end_dev_id); if (pp->dev_loss != DEV_LOSS_TMO_UNSET) { + ssize_t len, ret; + snprintf(value, 11, "%u", pp->dev_loss); - if (sysfs_attr_set_value(sas_dev, "I_T_nexus_loss_timeout", - value, strlen(value)) <= 0) - condlog(3, "%s: failed to update " - "I_T Nexus loss timeout, error %d", - pp->dev, errno); + len = strlen(value); + ret = sysfs_attr_set_value(sas_dev, "I_T_nexus_loss_timeout", + value, len); + if (ret != len) + log_sysfs_attr_set_value(3, ret, + "%s: failed to update I_T Nexus loss timeout", + pp->dev); } udev_device_unref(sas_dev); return; diff --git a/libmultipath/sysfs.c b/libmultipath/sysfs.c index 125f1c2..9c84af7 100644 --- a/libmultipath/sysfs.c +++ b/libmultipath/sysfs.c @@ -134,7 +134,7 @@ ssize_t sysfs_attr_set_value(struct udev_device *dev, const char *attr_name, /* write attribute value */ fd = open(devpath, O_WRONLY); if (fd < 0) { - condlog(2, "%s: attribute '%s' can not be opened: %s", + condlog(3, "%s: attribute '%s' can not be opened: %s", __func__, devpath, strerror(errno)); return -errno; } @@ -144,11 +144,9 @@ ssize_t sysfs_attr_set_value(struct udev_device *dev, const char *attr_name, size = -errno; condlog(3, "%s: write to %s failed: %s", __func__, devpath, strerror(errno)); - } else if (size < (ssize_t)value_len) { + } else if (size < (ssize_t)value_len) condlog(3, "%s: underflow writing %zu bytes to %s. Wrote %zd bytes", __func__, value_len, devpath, size); - size = 0; - } close(fd); return size; diff --git a/libmultipath/sysfs.h b/libmultipath/sysfs.h index cdc84e4..799f68e 100644 --- a/libmultipath/sysfs.h +++ b/libmultipath/sysfs.h @@ -5,6 +5,7 @@ #ifndef _LIBMULTIPATH_SYSFS_H #define _LIBMULTIPATH_SYSFS_H #include <stdbool.h> +#include "strbuf.h" ssize_t sysfs_attr_set_value(struct udev_device *dev, const char *attr_name, const char * value, size_t value_len); @@ -25,6 +26,15 @@ ssize_t sysfs_bin_attr_get_value(struct udev_device *dev, const char *attr_name, sysfs_attr_value_ok(__rc, __l); \ }) +#define log_sysfs_attr_set_value(prio, rc, fmt, __args...) \ +do { \ + STRBUF_ON_STACK(__buf); \ + if (print_strbuf(&__buf, fmt, ##__args) >= 0 && \ + print_strbuf(&__buf, ": %s", rc < 0 ? strerror(-rc) : \ + "write underflow") >= 0) \ + condlog(prio, "%s", get_strbuf_str(&__buf)); \ +} while(0) + int sysfs_get_size (struct path *pp, unsigned long long * size); int sysfs_check_holders(char * check_devt, char * new_devt); bool sysfs_is_multipathed(struct path *pp, bool set_wwid);