| Message ID | b9bb00ed-ff7c-df17-2228-60a3a36507f2@jp.fujitsu.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 10/23/2017 12:45 PM, Misono, Tomohiro wrote: > Currently "fi usage" (and "dev usage") cannot run for the filesystem using > seed device. > > This is because FS_INFO ioctl returns the number of devices excluding > seeds, but load_device_info() tries to access valid device from devid 0 > to max_id, and results in accessing seeds too (thus causing mismatching > of number of devices). A long time back I tried to fix this by fixing the FS_INFO num_devs itself, but the concern was backward compatibility of the ioctl. However there is no such a concern here. I am ok with this approach. > Since only the size of non-seed devices is matter, fix this by just > skipping seed device by checking device's fsid and comparing it to the fsid > obtained by FS_INFO ioctl. > > Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Thanks, Anand > --- > cmds-fi-usage.c | 15 +++++++++++++++ > 1 file changed, 15 insertions(+) > > diff --git a/cmds-fi-usage.c b/cmds-fi-usage.c > index a72fb4e..50c7e51 100644 > --- a/cmds-fi-usage.c > +++ b/cmds-fi-usage.c > @@ -545,6 +545,7 @@ static int load_device_info(int fd, struct device_info **device_info_ptr, > struct btrfs_ioctl_fs_info_args fi_args; > struct btrfs_ioctl_dev_info_args dev_info; > struct device_info *info; > + __u8 fsid[BTRFS_UUID_SIZE]; > > *device_info_count = 0; > *device_info_ptr = NULL; > @@ -568,6 +569,7 @@ static int load_device_info(int fd, struct device_info **device_info_ptr, > if (ndevs >= fi_args.num_devices) { > error("unexpected number of devices: %d >= %llu", ndevs, > (unsigned long long)fi_args.num_devices); > + error("if seed device is used, try run as root."); > goto out; > } > memset(&dev_info, 0, sizeof(dev_info)); > @@ -580,6 +582,19 @@ static int load_device_info(int fd, struct device_info **device_info_ptr, > goto out; > } > > + /* > + * Skip seed device by cheking device's fsid (require root). > + * Ignore EACCES since if seed is not used this function works > + * correctly without root privilege. > + */ > + ret = dev_to_fsid((const char *)dev_info.path, fsid); > + if (ret != -EACCES) { > + if (ret) > + goto out; > + if (memcmp(fi_args.fsid, fsid, BTRFS_FSID_SIZE) != 0) > + continue; > + } > + > info[ndevs].devid = dev_info.devid; > if (!dev_info.path[0]) { > strcpy(info[ndevs].path, "missing"); > -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/cmds-fi-usage.c b/cmds-fi-usage.c index a72fb4e..50c7e51 100644 --- a/cmds-fi-usage.c +++ b/cmds-fi-usage.c @@ -545,6 +545,7 @@ static int load_device_info(int fd, struct device_info **device_info_ptr, struct btrfs_ioctl_fs_info_args fi_args; struct btrfs_ioctl_dev_info_args dev_info; struct device_info *info; + __u8 fsid[BTRFS_UUID_SIZE]; *device_info_count = 0; *device_info_ptr = NULL; @@ -568,6 +569,7 @@ static int load_device_info(int fd, struct device_info **device_info_ptr, if (ndevs >= fi_args.num_devices) { error("unexpected number of devices: %d >= %llu", ndevs, (unsigned long long)fi_args.num_devices); + error("if seed device is used, try run as root."); goto out; } memset(&dev_info, 0, sizeof(dev_info)); @@ -580,6 +582,19 @@ static int load_device_info(int fd, struct device_info **device_info_ptr, goto out; } + /* + * Skip seed device by cheking device's fsid (require root). + * Ignore EACCES since if seed is not used this function works + * correctly without root privilege. + */ + ret = dev_to_fsid((const char *)dev_info.path, fsid); + if (ret != -EACCES) { + if (ret) + goto out; + if (memcmp(fi_args.fsid, fsid, BTRFS_FSID_SIZE) != 0) + continue; + } + info[ndevs].devid = dev_info.devid; if (!dev_info.path[0]) { strcpy(info[ndevs].path, "missing");
Currently "fi usage" (and "dev usage") cannot run for the filesystem using seed device. This is because FS_INFO ioctl returns the number of devices excluding seeds, but load_device_info() tries to access valid device from devid 0 to max_id, and results in accessing seeds too (thus causing mismatching of number of devices). Since only the size of non-seed devices is matter, fix this by just skipping seed device by checking device's fsid and comparing it to the fsid obtained by FS_INFO ioctl. Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com> --- cmds-fi-usage.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+)