| Message ID | 1383536745-4635-2-git-send-email-anand.jain@oracle.com (mailing list archive) |
|---|---|
| State | Under Review, archived |
| Headers | show |
On Mon, Nov 04, 2013 at 11:45:43AM +0800, Anand Jain wrote: > need fsinfo from btrfs-control that is when mount path is > not known. > current method of going through each mount points isn't > efficient, and multiple subvol of a fsid could be mounted > means extra logic to handle that. Further this will help > to revamp check_mounted() (planned) > > check_mounted is heavily used in the btrfs-progs, it > does full scan of all the disks in the system to confirm > if a multi-disk btrfs is mounted it doesn't scalable well > with few hundreds luns, check_mounted for sure needs a > revamp. using this it can be done easily. which is planned. > > v2: commit reword > > Signed-off-by: Anand Jain <anand.jain@oracle.com> > --- > ioctl.h | 19 +++++++++++++++ > utils.c | 80 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ > utils.h | 1 + > 3 files changed, 100 insertions(+), 0 deletions(-) > > diff --git a/ioctl.h b/ioctl.h > index d21413f..29575d8 100644 > --- a/ioctl.h > +++ b/ioctl.h > @@ -506,6 +506,23 @@ static inline char *btrfs_err_str(enum btrfs_err_code err_code) > } > } > > +/* fs flags */ > +#define BTRFS_FS_MOUNTED (1LLU << 0) > + > +struct btrfs_ioctl_fslist { > + __u64 self_sz; /* in/out */ > + __u8 fsid[BTRFS_FSID_SIZE]; /* out */ > + __u64 num_devices; > + __u64 missing_devices; > + __u64 total_devices; > + __u64 flags; > +}; > + > +struct btrfs_ioctl_fslist_args { > + __u64 self_sz; /* in/out */ > + __u64 count; /* out */ > +}; > + > #define BTRFS_IOC_SNAP_CREATE _IOW(BTRFS_IOCTL_MAGIC, 1, \ > struct btrfs_ioctl_vol_args) > #define BTRFS_IOC_DEFRAG _IOW(BTRFS_IOCTL_MAGIC, 2, \ > @@ -604,6 +621,8 @@ struct btrfs_ioctl_clone_range_args { > struct btrfs_ioctl_dev_replace_args) > #define BTRFS_IOC_DEDUP_CTL _IOWR(BTRFS_IOCTL_MAGIC, 55, \ > struct btrfs_ioctl_dedup_args) > +#define BTRFS_IOC_GET_FSLIST _IOWR(BTRFS_IOCTL_MAGIC, 56, \ > + struct btrfs_ioctl_fslist_args) > #ifdef __cplusplus > } > #endif > diff --git a/utils.c b/utils.c > index 5bedd97..1798a7c 100644 > --- a/utils.c > +++ b/utils.c > @@ -2087,3 +2087,83 @@ int lookup_ino_rootid(int fd, u64 *rootid) > > return 0; > } > + > +/* scans for fsid(s) in the kernel using the btrfs-control > + * interface. > + */ > +int get_fslist(struct btrfs_ioctl_fslist **out_fslist, int *out_count) > +{ > + int ret, fd, e; > + struct btrfs_ioctl_fslist_args *fsargs; > + struct btrfs_ioctl_fslist *fslist; > + struct btrfs_ioctl_fslist *fslist_tmp; > + u64 sz; > + int count; > + > + fd = open("/dev/btrfs-control", O_RDWR); > + e = errno; > + if (fd < 0) { > + perror("failed to open /dev/btrfs-control"); > + return -e; > + } > + > + /* space to hold 512 fsids, doesn't matter if small > + * it would fail and return count so then we try again > + */ > + count = 512; > +again: > + sz = sizeof(*fsargs) + sizeof(*fslist) * count; > + > + fsargs = (struct btrfs_ioctl_fslist_args *) malloc(sz); No need to cast the return value of malloc. > + memset(fsargs, 0, sz); > + > + if (!fsargs) { > + close(fd); > + return -ENOMEM; > + } Should check !fsargs before memsetting it. > + fsargs->count = count; > + > + ret = ioctl(fd, BTRFS_IOC_GET_FSLIST, fsargs); > + e = errno; > + if (ret == 1) { > + /* out of size so reallocate */ > + count = fsargs->count; > + free(fsargs); > + goto again; > + } else if (ret < 0) { > + printf("ERROR: scan_fsid ioctl failed - %s\n", > + strerror(e)); > + ret = -e; > + goto out; > + } > + > + /* ioctl returns fsid count in count parameter*/ > + > + *out_count = count = fsargs->count; > + if (count == 0) { > + *out_fslist = NULL; > + ret = 0; > + goto out; > + } > + > + fslist = (struct btrfs_ioctl_fslist *) (fsargs + > + sizeof(*fsargs)); > + > + fslist_tmp = *out_fslist = (struct btrfs_ioctl_fslist *) > + malloc(sizeof(*fslist) * count); No need to cast. Thanks, Josef -- 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
Thanks sent out v3. On 11/07/13 04:13 AM, Josef Bacik wrote: > On Mon, Nov 04, 2013 at 11:45:43AM +0800, Anand Jain wrote: >> need fsinfo from btrfs-control that is when mount path is >> not known. >> current method of going through each mount points isn't >> efficient, and multiple subvol of a fsid could be mounted >> means extra logic to handle that. Further this will help >> to revamp check_mounted() (planned) >> >> check_mounted is heavily used in the btrfs-progs, it >> does full scan of all the disks in the system to confirm >> if a multi-disk btrfs is mounted it doesn't scalable well >> with few hundreds luns, check_mounted for sure needs a >> revamp. using this it can be done easily. which is planned. >> >> v2: commit reword >> >> Signed-off-by: Anand Jain<anand.jain@oracle.com> >> --- >> ioctl.h | 19 +++++++++++++++ >> utils.c | 80 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ >> utils.h | 1 + >> 3 files changed, 100 insertions(+), 0 deletions(-) >> >> diff --git a/ioctl.h b/ioctl.h >> index d21413f..29575d8 100644 >> --- a/ioctl.h >> +++ b/ioctl.h >> @@ -506,6 +506,23 @@ static inline char *btrfs_err_str(enum btrfs_err_code err_code) >> } >> } >> >> +/* fs flags */ >> +#define BTRFS_FS_MOUNTED (1LLU<< 0) >> + >> +struct btrfs_ioctl_fslist { >> + __u64 self_sz; /* in/out */ >> + __u8 fsid[BTRFS_FSID_SIZE]; /* out */ >> + __u64 num_devices; >> + __u64 missing_devices; >> + __u64 total_devices; >> + __u64 flags; >> +}; >> + >> +struct btrfs_ioctl_fslist_args { >> + __u64 self_sz; /* in/out */ >> + __u64 count; /* out */ >> +}; >> + >> #define BTRFS_IOC_SNAP_CREATE _IOW(BTRFS_IOCTL_MAGIC, 1, \ >> struct btrfs_ioctl_vol_args) >> #define BTRFS_IOC_DEFRAG _IOW(BTRFS_IOCTL_MAGIC, 2, \ >> @@ -604,6 +621,8 @@ struct btrfs_ioctl_clone_range_args { >> struct btrfs_ioctl_dev_replace_args) >> #define BTRFS_IOC_DEDUP_CTL _IOWR(BTRFS_IOCTL_MAGIC, 55, \ >> struct btrfs_ioctl_dedup_args) >> +#define BTRFS_IOC_GET_FSLIST _IOWR(BTRFS_IOCTL_MAGIC, 56, \ >> + struct btrfs_ioctl_fslist_args) >> #ifdef __cplusplus >> } >> #endif >> diff --git a/utils.c b/utils.c >> index 5bedd97..1798a7c 100644 >> --- a/utils.c >> +++ b/utils.c >> @@ -2087,3 +2087,83 @@ int lookup_ino_rootid(int fd, u64 *rootid) >> >> return 0; >> } >> + >> +/* scans for fsid(s) in the kernel using the btrfs-control >> + * interface. >> + */ >> +int get_fslist(struct btrfs_ioctl_fslist **out_fslist, int *out_count) >> +{ >> + int ret, fd, e; >> + struct btrfs_ioctl_fslist_args *fsargs; >> + struct btrfs_ioctl_fslist *fslist; >> + struct btrfs_ioctl_fslist *fslist_tmp; >> + u64 sz; >> + int count; >> + >> + fd = open("/dev/btrfs-control", O_RDWR); >> + e = errno; >> + if (fd< 0) { >> + perror("failed to open /dev/btrfs-control"); >> + return -e; >> + } >> + >> + /* space to hold 512 fsids, doesn't matter if small >> + * it would fail and return count so then we try again >> + */ >> + count = 512; >> +again: >> + sz = sizeof(*fsargs) + sizeof(*fslist) * count; >> + >> + fsargs = (struct btrfs_ioctl_fslist_args *) malloc(sz); > > No need to cast the return value of malloc. > >> + memset(fsargs, 0, sz); >> + >> + if (!fsargs) { >> + close(fd); >> + return -ENOMEM; >> + } > > Should check !fsargs before memsetting it. > >> + fsargs->count = count; >> + >> + ret = ioctl(fd, BTRFS_IOC_GET_FSLIST, fsargs); >> + e = errno; >> + if (ret == 1) { >> + /* out of size so reallocate */ >> + count = fsargs->count; >> + free(fsargs); >> + goto again; >> + } else if (ret< 0) { >> + printf("ERROR: scan_fsid ioctl failed - %s\n", >> + strerror(e)); >> + ret = -e; >> + goto out; >> + } >> + >> + /* ioctl returns fsid count in count parameter*/ >> + >> + *out_count = count = fsargs->count; >> + if (count == 0) { >> + *out_fslist = NULL; >> + ret = 0; >> + goto out; >> + } >> + >> + fslist = (struct btrfs_ioctl_fslist *) (fsargs + >> + sizeof(*fsargs)); >> + >> + fslist_tmp = *out_fslist = (struct btrfs_ioctl_fslist *) >> + malloc(sizeof(*fslist) * count); > > No need to cast. Thanks, > > Josef > -- > 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 -- 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/ioctl.h b/ioctl.h index d21413f..29575d8 100644 --- a/ioctl.h +++ b/ioctl.h @@ -506,6 +506,23 @@ static inline char *btrfs_err_str(enum btrfs_err_code err_code) } } +/* fs flags */ +#define BTRFS_FS_MOUNTED (1LLU << 0) + +struct btrfs_ioctl_fslist { + __u64 self_sz; /* in/out */ + __u8 fsid[BTRFS_FSID_SIZE]; /* out */ + __u64 num_devices; + __u64 missing_devices; + __u64 total_devices; + __u64 flags; +}; + +struct btrfs_ioctl_fslist_args { + __u64 self_sz; /* in/out */ + __u64 count; /* out */ +}; + #define BTRFS_IOC_SNAP_CREATE _IOW(BTRFS_IOCTL_MAGIC, 1, \ struct btrfs_ioctl_vol_args) #define BTRFS_IOC_DEFRAG _IOW(BTRFS_IOCTL_MAGIC, 2, \ @@ -604,6 +621,8 @@ struct btrfs_ioctl_clone_range_args { struct btrfs_ioctl_dev_replace_args) #define BTRFS_IOC_DEDUP_CTL _IOWR(BTRFS_IOCTL_MAGIC, 55, \ struct btrfs_ioctl_dedup_args) +#define BTRFS_IOC_GET_FSLIST _IOWR(BTRFS_IOCTL_MAGIC, 56, \ + struct btrfs_ioctl_fslist_args) #ifdef __cplusplus } #endif diff --git a/utils.c b/utils.c index 5bedd97..1798a7c 100644 --- a/utils.c +++ b/utils.c @@ -2087,3 +2087,83 @@ int lookup_ino_rootid(int fd, u64 *rootid) return 0; } + +/* scans for fsid(s) in the kernel using the btrfs-control + * interface. + */ +int get_fslist(struct btrfs_ioctl_fslist **out_fslist, int *out_count) +{ + int ret, fd, e; + struct btrfs_ioctl_fslist_args *fsargs; + struct btrfs_ioctl_fslist *fslist; + struct btrfs_ioctl_fslist *fslist_tmp; + u64 sz; + int count; + + fd = open("/dev/btrfs-control", O_RDWR); + e = errno; + if (fd < 0) { + perror("failed to open /dev/btrfs-control"); + return -e; + } + + /* space to hold 512 fsids, doesn't matter if small + * it would fail and return count so then we try again + */ + count = 512; +again: + sz = sizeof(*fsargs) + sizeof(*fslist) * count; + + fsargs = (struct btrfs_ioctl_fslist_args *) malloc(sz); + memset(fsargs, 0, sz); + + if (!fsargs) { + close(fd); + return -ENOMEM; + } + fsargs->count = count; + + ret = ioctl(fd, BTRFS_IOC_GET_FSLIST, fsargs); + e = errno; + if (ret == 1) { + /* out of size so reallocate */ + count = fsargs->count; + free(fsargs); + goto again; + } else if (ret < 0) { + printf("ERROR: scan_fsid ioctl failed - %s\n", + strerror(e)); + ret = -e; + goto out; + } + + /* ioctl returns fsid count in count parameter*/ + + *out_count = count = fsargs->count; + if (count == 0) { + *out_fslist = NULL; + ret = 0; + goto out; + } + + fslist = (struct btrfs_ioctl_fslist *) (fsargs + + sizeof(*fsargs)); + + fslist_tmp = *out_fslist = (struct btrfs_ioctl_fslist *) + malloc(sizeof(*fslist) * count); + if (!fslist_tmp) { + ret = -ENOMEM; + goto out; + } + + while (count--) { + memcpy(fslist_tmp, fslist, sizeof(*fslist)); + fslist_tmp = fslist_tmp + sizeof(*fslist_tmp); + fslist = fslist + sizeof(*fslist); + } + ret = 0; +out: + free(fsargs); + close(fd); + return 0; +} diff --git a/utils.h b/utils.h index 6f4b10c..e20ad74 100644 --- a/utils.h +++ b/utils.h @@ -94,5 +94,6 @@ int ask_user(char *question); int lookup_ino_rootid(int fd, u64 *rootid); int btrfs_scan_lblkid(int update_kernel); int get_btrfs_mount(const char *dev, char *mp, size_t mp_size); +int get_fslist(struct btrfs_ioctl_fslist **out_fslist, int *out_count); #endif
need fsinfo from btrfs-control that is when mount path is not known. current method of going through each mount points isn't efficient, and multiple subvol of a fsid could be mounted means extra logic to handle that. Further this will help to revamp check_mounted() (planned) check_mounted is heavily used in the btrfs-progs, it does full scan of all the disks in the system to confirm if a multi-disk btrfs is mounted it doesn't scalable well with few hundreds luns, check_mounted for sure needs a revamp. using this it can be done easily. which is planned. v2: commit reword Signed-off-by: Anand Jain <anand.jain@oracle.com> --- ioctl.h | 19 +++++++++++++++ utils.c | 80 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ utils.h | 1 + 3 files changed, 100 insertions(+), 0 deletions(-)