Hello, On Wed 15-04-15 09:15:43, Beata Michalska wrote: > The following patchset is a result of previous discussions regarding > file system threshold notifiactions. It introduces support for file > system event notifications, sent through generic netlinik interface > whenever an fs-related event occurs. Included are also some shmem > and ext4 changes showing how the new interface might actually be used. > > The vary idea of using the generic netlink interface has been previoulsy > suggested here: https://lkml.org/lkml/2011/8/18/169 > > The basic description of the new functionality can be found in > the first patch from this set - both in the commit message and > in the doc file. > > Some very basic tests have been performed though still this is > a PoC version. Below though is a sample user space application > which subscribes to the new multicast group and listens for > potential fs-related events. The code has been based on libnl 3.4 > and its test application for the generic netlink. Thanks for the patches! As a general note for the next posting, please CC also linux-fsdevel@xxxxxxxxxxxxxxx (since this has implications for other filesystems as well, specifically I know about XFS guys thinking about some notification system as well) and linux-api@xxxxxxxxxxxxxxx (since this is a new kernel interface to userspace). Honza > > --- > > Beata Michalska (4): > fs: Add generic file system event notifications > ext4: Add helper function to mark group as corrupted > ext4: Add support for generic FS events > shmem: Add support for generic FS events > > Documentation/filesystems/events.txt | 254 +++++++++++ > fs/Makefile | 1 + > fs/events/Makefile | 6 + > fs/events/fs_event.c | 775 ++++++++++++++++++++++++++++++++++ > fs/events/fs_event.h | 27 ++ > fs/events/fs_event_netlink.c | 94 +++++ > fs/ext4/balloc.c | 26 +- > fs/ext4/ext4.h | 10 + > fs/ext4/ialloc.c | 5 +- > fs/ext4/inode.c | 2 +- > fs/ext4/mballoc.c | 17 +- > fs/ext4/resize.c | 1 + > fs/ext4/super.c | 43 ++ > fs/namespace.c | 1 + > include/linux/fs.h | 6 +- > include/linux/fs_event.h | 69 +++ > include/uapi/linux/fs_event.h | 62 +++ > include/uapi/linux/genetlink.h | 1 + > mm/shmem.c | 39 +- > net/netlink/genetlink.c | 7 +- > 20 files changed, 1412 insertions(+), 34 deletions(-) > create mode 100644 Documentation/filesystems/events.txt > create mode 100644 fs/events/Makefile > create mode 100644 fs/events/fs_event.c > create mode 100644 fs/events/fs_event.h > create mode 100644 fs/events/fs_event_netlink.c > create mode 100644 include/linux/fs_event.h > create mode 100644 include/uapi/linux/fs_event.h > > --- > Sample application: > > #include <netlink/cli/utils.h> > #include <fs_event.h> > > #define ARRAY_SIZE(x) (sizeof(x)/sizeof((x)[0])) > #define LOG(args...) fprintf(stderr, args) > > static int parse_info(struct nl_cache_ops *unused, struct genl_cmd *cmd, > struct genl_info *info, void *arg) > { > LOG("New trace %d:\n", > info->attrs[FS_EVENT_ATR_FS_ID] > ? nla_get_u32(info->attrs[FS_EVENT_ATR_FS_ID]) > : -1); > LOG("Mout point: %s\n", info->attrs[FS_EVENT_ATR_MOUNT] > ? nla_get_string(info->attrs[FS_EVENT_ATR_MOUNT]) > : "unknown"); > return 0; > } > > static int parse_thres(struct nl_cache_ops *unused, struct genl_cmd *cmd, > struct genl_info *info, void *arg) > { > > LOG("Threshold notification received for trace %d:\n", > info->attrs[FS_EVENT_ATR_FS_ID] > ? nla_get_u32(info->attrs[FS_EVENT_ATR_FS_ID]) > : -1); > > if (info->attrs[FS_EVENT_ATR_DEV_MAJOR]) > LOG("Backing dev major: %u\n", > nla_get_u32(info->attrs[FS_EVENT_ATR_DEV_MAJOR])); > if (info->attrs[FS_EVENT_ATR_DEV_MINOR]) > LOG("Backing dev minor: %u\n", > nla_get_u32(info->attrs[FS_EVENT_ATR_DEV_MINOR])); > LOG("Proc: %u\n", info->attrs[FS_EVENT_ATR_CAUSED_ID] ? > nla_get_u32(info->attrs[FS_EVENT_ATR_CAUSED_ID]) : -1); > LOG("Threshold data: %llu\n", info->attrs[FS_EVENT_ATR_DATA] > ? nla_get_u64(info->attrs[FS_EVENT_ATR_DATA]) > : 0); > > return 0; > } > > static int parse_warning(struct nl_cache_ops *unused, struct genl_cmd *cmd, > struct genl_info *info, void *arg) > { > > LOG("Warning recieved for trace %d\n", info->attrs[FS_EVENT_ATR_FS_ID] ? > nla_get_u32(info->attrs[FS_EVENT_ATR_FS_ID]) : -1); > if (info->attrs[FS_EVENT_ATR_DEV_MAJOR]) > LOG("Backing dev major: %u\n", > nla_get_u32(info->attrs[FS_EVENT_ATR_DEV_MAJOR])); > if (info->attrs[FS_EVENT_ATR_DEV_MINOR]) > LOG("Backing dev minor: %u\n", > nla_get_u32(info->attrs[FS_EVENT_ATR_DEV_MINOR])); > LOG("Proc: %u\n", info->attrs[FS_EVENT_ATR_CAUSED_ID] ? > nla_get_u32(info->attrs[FS_EVENT_ATR_CAUSED_ID]) : -1); > LOG("Warning: %u\n", info->attrs[FS_EVENT_ATR_ID] ? > nla_get_u32(info->attrs[FS_EVENT_ATR_ID]) : -1); > > return 0; > } > > static struct genl_cmd cmd[] = { > { > .c_id = FS_EVENT_TYPE_NEW_TRACE, > .c_name = "info", > .c_maxattr = 2, > .c_msg_parser = parse_info, > }, { > .c_id = FS_EVENT_TYPE_THRESH, > .c_name = "thres", > .c_maxattr = 6, > .c_msg_parser = parse_thres, > }, { > .c_id = FS_EVENT_TYPE_WARN, > .c_name = "warn", > .c_maxattr = 5, > .c_msg_parser = parse_warning, > }, > }; > > static struct genl_ops ops = { > .o_id = GENL_ID_FS_EVENT, > .o_name = "FS_EVENT", > .o_hdrsize = 0, > .o_cmds = cmd, > .o_ncmds = ARRAY_SIZE(cmd), > }; > > > int events_cb(struct nl_msg *msg, void *arg) > { > return genl_handle_msg(msg, arg); > } > > int main(int argc, char **argv) > { > struct nl_sock *sock; > int ret; > > sock = nl_cli_alloc_socket(); > nl_socket_set_local_port(sock, 0); > nl_socket_disable_seq_check(sock); > > nl_socket_modify_cb(sock, NL_CB_VALID, NL_CB_CUSTOM, events_cb, NULL); > > nl_cli_connect(sock, NETLINK_GENERIC); > > if ((ret = nl_socket_add_membership(sock, GENL_ID_FS_EVENT))) { > LOG("Failed to add membership\n"); > goto leave; > } > > if((ret = genl_register_family(&ops))) { > LOG("Failed to register protocol family\n"); > goto leave; > } > > if ((ret = genl_ops_resolve(sock, &ops) < 0)) { > LOG("Unable to resolve the family name\n"); > goto leave; > } > > if (genl_ctrl_resolve(sock, "FS_EVENT") < 0) { > LOG("Failed to resolve the family name\n"); > goto leave; > } > > while (1) { > if ((ret = nl_recvmsgs_default(sock)) < 0) > LOG("Unable to receive message: %s\n", nl_geterror(ret)); > } > > leave: > nl_close(sock); > nl_socket_free(sock); > return 0; > } > > -- > 1.7.9.5 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-ext4" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Jan Kara <jack@xxxxxxx> SUSE Labs, CR -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. 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