From: Darrick J. Wong <[email protected]> Use Kent Overstreet's thread_with_file abstraction to provide a magic file from which we can read filesystem health events.
Signed-off-by: Darrick J. Wong <[email protected]> --- fs/xfs/Kconfig | 9 +++ fs/xfs/Makefile | 1 fs/xfs/libxfs/xfs_fs.h | 1 fs/xfs/libxfs/xfs_fs_staging.h | 10 +++ fs/xfs/xfs_healthmon.c | 129 ++++++++++++++++++++++++++++++++++++++++ fs/xfs/xfs_healthmon.h | 15 +++++ fs/xfs/xfs_ioctl.c | 21 +++++++ fs/xfs/xfs_linux.h | 3 + 8 files changed, 189 insertions(+) create mode 100644 fs/xfs/xfs_healthmon.c create mode 100644 fs/xfs/xfs_healthmon.h diff --git a/fs/xfs/Kconfig b/fs/xfs/Kconfig index e0fa9b382fbeb..dd22cf799328a 100644 --- a/fs/xfs/Kconfig +++ b/fs/xfs/Kconfig @@ -6,6 +6,7 @@ config XFS_FS select LIBCRC32C select FS_IOMAP select TIME_STATS if XFS_TIME_STATS + select THREAD_WITH_FILE if XFS_HEALTH_MONITOR help XFS is a high performance journaling filesystem which originated on the SGI IRIX platform. It is completely multi-threaded, can @@ -128,6 +129,14 @@ config XFS_TIME_STATS help Collects time statistics on various operations in the filesystem. +config XFS_HEALTH_MONITOR + bool "Report filesystem health events to userspace" + depends on XFS_FS + select XFS_LIVE_HOOKS + default y + help + Report health events to userspace programs. + config XFS_DRAIN_INTENTS bool select JUMP_LABEL if HAVE_ARCH_JUMP_LABEL diff --git a/fs/xfs/Makefile b/fs/xfs/Makefile index bf3bacfb7afff..563936e48ab39 100644 --- a/fs/xfs/Makefile +++ b/fs/xfs/Makefile @@ -154,6 +154,7 @@ xfs-$(CONFIG_XFS_LIVE_HOOKS) += xfs_hooks.o xfs-$(CONFIG_XFS_MEMORY_BUFS) += xfs_buf_mem.o xfs-$(CONFIG_XFS_BTREE_IN_MEM) += libxfs/xfs_btree_mem.o xfs-$(CONFIG_XFS_TIME_STATS) += xfs_timestats.o +xfs-$(CONFIG_XFS_HEALTH_MONITOR) += xfs_healthmon.o # online scrub/repair ifeq ($(CONFIG_XFS_ONLINE_SCRUB),y) diff --git a/fs/xfs/libxfs/xfs_fs.h b/fs/xfs/libxfs/xfs_fs.h index 246c2582abbe5..b9d9bc511475d 100644 --- a/fs/xfs/libxfs/xfs_fs.h +++ b/fs/xfs/libxfs/xfs_fs.h @@ -855,6 +855,7 @@ struct xfs_scrub_metadata { #define XFS_IOC_FSGETXATTRA _IOR ('X', 45, struct fsxattr) /* XFS_IOC_SETBIOSIZE ---- deprecated 46 */ /* XFS_IOC_GETBIOSIZE ---- deprecated 47 */ +/* XFS_IOC_HEALTHMON -------- staging 48 */ #define XFS_IOC_GETBMAPX _IOWR('X', 56, struct getbmap) #define XFS_IOC_ZERO_RANGE _IOW ('X', 57, struct xfs_flock64) #define XFS_IOC_FREE_EOFBLOCKS _IOR ('X', 58, struct xfs_fs_eofblocks) diff --git a/fs/xfs/libxfs/xfs_fs_staging.h b/fs/xfs/libxfs/xfs_fs_staging.h index 1da182c77934d..84b99816eec2e 100644 --- a/fs/xfs/libxfs/xfs_fs_staging.h +++ b/fs/xfs/libxfs/xfs_fs_staging.h @@ -303,4 +303,14 @@ struct xfs_map_freesp { */ #define XFS_IOC_MAP_FREESP _IOWR('X', 64, struct xfs_map_freesp) +struct xfs_health_monitor { + __u64 flags; /* flags */ + __u8 format; /* output format */ + __u8 pad1[7]; /* zeroes */ + __u64 pad2[2]; /* zeroes */ +}; + +/* Monitor for health events. */ +#define XFS_IOC_HEALTH_MONITOR _IOR ('X', 48, struct xfs_health_monitor) + #endif /* __XFS_FS_STAGING_H__ */ diff --git a/fs/xfs/xfs_healthmon.c b/fs/xfs/xfs_healthmon.c new file mode 100644 index 0000000000000..9b4da8d1e5173 --- /dev/null +++ b/fs/xfs/xfs_healthmon.c @@ -0,0 +1,129 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2024 Oracle. All Rights Reserved. + * Author: Darrick J. Wong <[email protected]> + */ +#include "xfs.h" +#include "xfs_fs.h" +#include "xfs_shared.h" +#include "xfs_format.h" +#include "xfs_log_format.h" +#include "xfs_trans_resv.h" +#include "xfs_mount.h" +#include "xfs_inode.h" +#include "xfs_trace.h" +#include "xfs_health.h" +#include "xfs_ag.h" +#include "xfs_btree.h" +#include "xfs_da_format.h" +#include "xfs_da_btree.h" +#include "xfs_quota_defs.h" +#include "xfs_rtgroup.h" +#include "xfs_healthmon.h" + +/* + * Live Health Monitoring + * ====================== + * + * Autonomous self-healing of XFS filesystems requires a means for the kernel + * to send filesystem health events to a monitoring daemon in userspace. To + * accomplish this, we establish a thread_with_file kthread object to handle + * translating internal events about filesystem health into a format that can + * be parsed easily by userspace. Then we hook various parts of the filesystem + * to supply those internal events to the kthread. Userspace reads events + * from the file descriptor returned by the ioctl. + * + * The healthmon abstraction has a weak reference to the host filesystem mount + * so that the queueing and processing of the events do not pin the mount and + * cannot slow down the main filesystem. The healthmon object can exist past + * the end of the filesystem mount. + */ + +struct xfs_healthmon { + /* thread with stdio redirection */ + struct thread_with_stdio thread; +}; + +static inline struct xfs_healthmon * +to_healthmon(struct thread_with_stdio *thr) +{ + return container_of(thr, struct xfs_healthmon, thread); +} + +/* Free the health monitoring information. */ +STATIC void +xfs_healthmon_exit( + struct thread_with_stdio *thr) +{ + struct xfs_healthmon *hm = to_healthmon(thr); + + kfree(hm); + module_put(THIS_MODULE); +} + +/* Pipe health monitoring information to userspace. */ +STATIC void +xfs_healthmon_run( + struct thread_with_stdio *thr) +{ +} + +/* Validate ioctl parameters. */ +static inline bool +xfs_healthmon_validate( + const struct xfs_health_monitor *hmo) +{ + if (hmo->flags) + return false; + if (hmo->format) + return false; + if (memchr_inv(&hmo->pad1, 0, sizeof(hmo->pad1))) + return false; + if (memchr_inv(&hmo->pad2, 0, sizeof(hmo->pad2))) + return false; + return true; +} + +static const struct thread_with_stdio_ops xfs_healthmon_ops = { + .exit = xfs_healthmon_exit, + .fn = xfs_healthmon_run, +}; + +/* + * Create a health monitoring file. Returns an index to the fd table or a + * negative errno. + */ +int +xfs_healthmon_create( + struct xfs_mount *mp, + struct xfs_health_monitor *hmo) +{ + struct xfs_healthmon *hm; + int ret; + + if (!xfs_healthmon_validate(hmo)) + return -EINVAL; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + if (!try_module_get(THIS_MODULE)) + return -ENOMEM; + + hm = kzalloc(sizeof(*hm), GFP_KERNEL); + if (!hm) { + ret = -ENOMEM; + goto out_mod; + } + + ret = run_thread_with_stdout(&hm->thread, &xfs_healthmon_ops); + if (ret < 0) + goto out_hm; + + return ret; +out_hm: + kfree(hm); +out_mod: + module_put(THIS_MODULE); + return ret; +} diff --git a/fs/xfs/xfs_healthmon.h b/fs/xfs/xfs_healthmon.h new file mode 100644 index 0000000000000..a9a8115ec770b --- /dev/null +++ b/fs/xfs/xfs_healthmon.h @@ -0,0 +1,15 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Copyright (C) 2024 Oracle. All Rights Reserved. + * Author: Darrick J. Wong <[email protected]> + */ +#ifndef __XFS_HEALTHMON_H__ +#define __XFS_HEALTHMON_H__ + +#ifdef CONFIG_XFS_HEALTH_MONITOR +int xfs_healthmon_create(struct xfs_mount *mp, struct xfs_health_monitor *hmo); +#else +# define xfs_healthmon_create(mp, hmo) (-EOPNOTSUPP) +#endif /* CONFIG_XFS_HEALTH_MONITOR */ + +#endif /* __XFS_HEALTHMON_H__ */ diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c index d592ceb26c3e5..270127300ba02 100644 --- a/fs/xfs/xfs_ioctl.c +++ b/fs/xfs/xfs_ioctl.c @@ -44,6 +44,7 @@ #include "xfs_file.h" #include "xfs_exchrange.h" #include "xfs_rtgroup.h" +#include "xfs_healthmon.h" #include <linux/mount.h> #include <linux/namei.h> @@ -2429,6 +2430,23 @@ xfs_ioc_map_freesp( # define xfs_ioc_map_freesp(...) (-ENOTTY) #endif +#ifdef CONFIG_XFS_EXPERIMENTAL_IOCTLS +STATIC int +xfs_ioc_health_monitor( + struct xfs_mount *mp, + struct xfs_health_monitor __user *arg) +{ + struct xfs_health_monitor hmo; + + if (copy_from_user(&hmo, arg, sizeof(hmo))) + return -EFAULT; + + return xfs_healthmon_create(mp, &hmo); +} +#else +# define xfs_ioc_health_monitor(...) (-ENOTTY) +#endif + /* * These long-unused ioctls were removed from the official ioctl API in 5.17, * but retain these definitions so that we can log warnings about them. @@ -2685,6 +2703,9 @@ xfs_file_ioctl( case XFS_IOC_MAP_FREESP: return xfs_ioc_map_freesp(filp, arg); + case XFS_IOC_HEALTH_MONITOR: + return xfs_ioc_health_monitor(mp, arg); + default: return -ENOTTY; } diff --git a/fs/xfs/xfs_linux.h b/fs/xfs/xfs_linux.h index 8598294514aa3..02dc0aba4e728 100644 --- a/fs/xfs/xfs_linux.h +++ b/fs/xfs/xfs_linux.h @@ -69,6 +69,9 @@ typedef __u32 xfs_nlink_t; # include <linux/time_stats.h> #endif #include <linux/sched/clock.h> +#ifdef CONFIG_XFS_HEALTH_MONITOR +# include <linux/thread_with_file.h> +#endif #include <asm/page.h> #include <asm/div64.h>
