From a5f7a5bb3b7f28ba7e4fa246775b29a0e5537255 Mon Sep 17 00:00:00 2001 From: Jinke Han Date: Tue, 8 Sep 2026 15:37:42 +0800 Subject: x86/kprobes: Fix crash when probing CS CALL instructions When using eBPF to probe CS CALL instructions within a function, a crash can be triggered. The eBPF tool probes offset 257 of the __hrtimer_run_queues() function: <__hrtimer_run_queues+249>: nopl 0x0(%rax,%rax,1) <__hrtimer_run_queues+254>: mov %r14,%rdi <__hrtimer_run_queues+257>: cs call <__x86_indirect_thunk_r12> <__hrtimer_run_queues+263>: mov %eax,%r12d <__hrtimer_run_queues+266>: xchg %ax,%ax <__hrtimer_run_queues+268>: mov %r13,%rdi Which triggers this crash: BUG: unable to handle page fault for address: 00000000000f41c9 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 0 P4D 0 Oops: 0002 [#1] SMP NOPTI CPU: 1 PID: 0 Comm: swapper/1 Kdump: loaded Tainted: P RIP: 0010:__hrtimer_run_queues+0x106/0x230 Note that __hrtimer_run_queues+0x106 is __hrtimer_run_queues+262, which is at the 6th byte of the above CS CALL instruction. Since the CS CALL instruction occupies 6 bytes, the exception occurred in the middle of that call instruction. The root cause is that when using eBPF tools to probe in the middle of a function, a kprobe with INT3 is used as the underlying implementation. During single-step emulation of the original CALL instruction, int3_emulate_call() assumes that the probed CALL instruction is 5 bytes long. However, the actual CS-prefixed CALL instruction occupies 6 bytes, so it constructs an incorrect exception return address. When the CPU returns from the kprobe handler, the next instruction to be executed is at the address of the last byte of that CS CALL instruction. Coincidentally, starting from that address, the CPU fetches and decodes a completely different instruction, which ultimately triggers a kernel crash. Fix the issue by using the actual instruction length obtained from the instruction decoder when constructing the exception return address, rather than relying on the hardcoded CALL_INSN_SIZE macro. [ mingo: Refined the changelog ] Fixes: 6256e668b7af ("x86/kprobes: Use int3 instead of debug trap for single-step") Suggested-by: Masami Hiramatsu (Google) Signed-off-by: Jinke Han Signed-off-by: Ingo Molnar Reviewed-by: Masami Hiramatsu (Google) Acked-by: Yafang Shao Acked-by: Borislav Petkov Cc: Peter Zijlstra Link: https://patch.msgid.link/20260908073742.GA10517@didi-ThinkCentre-M920t-N000 --- fs/nilfs2/sysfs.c | 1140 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1140 insertions(+) create mode 100644 fs/nilfs2/sysfs.c (limited to 'fs/nilfs2/sysfs.c') diff --git a/fs/nilfs2/sysfs.c b/fs/nilfs2/sysfs.c new file mode 100644 index 000000000..bc52afbfc --- /dev/null +++ b/fs/nilfs2/sysfs.c @@ -0,0 +1,1140 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Sysfs support implementation. + * + * Copyright (C) 2005-2014 Nippon Telegraph and Telephone Corporation. + * Copyright (C) 2014 HGST, Inc., a Western Digital Company. + * + * Written by Vyacheslav Dubeyko + */ + +#include + +#include "nilfs.h" +#include "mdt.h" +#include "sufile.h" +#include "cpfile.h" +#include "sysfs.h" + +/* /sys/fs// */ +static struct kset *nilfs_kset; + +#define NILFS_DEV_INT_GROUP_OPS(name, parent_name) \ +static ssize_t nilfs_##name##_attr_show(struct kobject *kobj, \ + struct attribute *attr, char *buf) \ +{ \ + struct the_nilfs *nilfs = container_of(kobj->parent, \ + struct the_nilfs, \ + ns_##parent_name##_kobj); \ + struct nilfs_##name##_attr *a = container_of(attr, \ + struct nilfs_##name##_attr, \ + attr); \ + return a->show ? a->show(a, nilfs, buf) : 0; \ +} \ +static ssize_t nilfs_##name##_attr_store(struct kobject *kobj, \ + struct attribute *attr, \ + const char *buf, size_t len) \ +{ \ + struct the_nilfs *nilfs = container_of(kobj->parent, \ + struct the_nilfs, \ + ns_##parent_name##_kobj); \ + struct nilfs_##name##_attr *a = container_of(attr, \ + struct nilfs_##name##_attr, \ + attr); \ + return a->store ? a->store(a, nilfs, buf, len) : 0; \ +} \ +static const struct sysfs_ops nilfs_##name##_attr_ops = { \ + .show = nilfs_##name##_attr_show, \ + .store = nilfs_##name##_attr_store, \ +} + +#define NILFS_DEV_INT_GROUP_TYPE(name, parent_name) \ +static void nilfs_##name##_attr_release(struct kobject *kobj) \ +{ \ + struct nilfs_sysfs_##parent_name##_subgroups *subgroups = container_of(kobj, \ + struct nilfs_sysfs_##parent_name##_subgroups, \ + sg_##name##_kobj); \ + complete(&subgroups->sg_##name##_kobj_unregister); \ +} \ +static const struct kobj_type nilfs_##name##_ktype = { \ + .default_groups = nilfs_##name##_groups, \ + .sysfs_ops = &nilfs_##name##_attr_ops, \ + .release = nilfs_##name##_attr_release, \ +} + +#define NILFS_DEV_INT_GROUP_FNS(name, parent_name) \ +static int nilfs_sysfs_create_##name##_group(struct the_nilfs *nilfs) \ +{ \ + struct kobject *parent; \ + struct kobject *kobj; \ + struct completion *kobj_unregister; \ + struct nilfs_sysfs_##parent_name##_subgroups *subgroups; \ + int err; \ + subgroups = nilfs->ns_##parent_name##_subgroups; \ + kobj = &subgroups->sg_##name##_kobj; \ + kobj_unregister = &subgroups->sg_##name##_kobj_unregister; \ + parent = &nilfs->ns_##parent_name##_kobj; \ + kobj->kset = nilfs_kset; \ + init_completion(kobj_unregister); \ + err = kobject_init_and_add(kobj, &nilfs_##name##_ktype, parent, \ + #name); \ + if (err) \ + kobject_put(kobj); \ + return err; \ +} \ +static void nilfs_sysfs_delete_##name##_group(struct the_nilfs *nilfs) \ +{ \ + kobject_put(&nilfs->ns_##parent_name##_subgroups->sg_##name##_kobj); \ +} + +/************************************************************************ + * NILFS snapshot attrs * + ************************************************************************/ + +static ssize_t +nilfs_snapshot_inodes_count_show(struct nilfs_snapshot_attr *attr, + struct nilfs_root *root, char *buf) +{ + return sysfs_emit(buf, "%llu\n", + (unsigned long long)atomic64_read(&root->inodes_count)); +} + +static ssize_t +nilfs_snapshot_blocks_count_show(struct nilfs_snapshot_attr *attr, + struct nilfs_root *root, char *buf) +{ + return sysfs_emit(buf, "%llu\n", + (unsigned long long)atomic64_read(&root->blocks_count)); +} + +static const char snapshot_readme_str[] = + "The group contains details about mounted snapshot.\n\n" + "(1) inodes_count\n\tshow number of inodes for snapshot.\n\n" + "(2) blocks_count\n\tshow number of blocks for snapshot.\n\n"; + +static ssize_t +nilfs_snapshot_README_show(struct nilfs_snapshot_attr *attr, + struct nilfs_root *root, char *buf) +{ + return sysfs_emit(buf, snapshot_readme_str); +} + +NILFS_SNAPSHOT_RO_ATTR(inodes_count); +NILFS_SNAPSHOT_RO_ATTR(blocks_count); +NILFS_SNAPSHOT_RO_ATTR(README); + +static struct attribute *nilfs_snapshot_attrs[] = { + NILFS_SNAPSHOT_ATTR_LIST(inodes_count), + NILFS_SNAPSHOT_ATTR_LIST(blocks_count), + NILFS_SNAPSHOT_ATTR_LIST(README), + NULL, +}; +ATTRIBUTE_GROUPS(nilfs_snapshot); + +static ssize_t nilfs_snapshot_attr_show(struct kobject *kobj, + struct attribute *attr, char *buf) +{ + struct nilfs_root *root = + container_of(kobj, struct nilfs_root, snapshot_kobj); + struct nilfs_snapshot_attr *a = + container_of(attr, struct nilfs_snapshot_attr, attr); + + return a->show ? a->show(a, root, buf) : 0; +} + +static ssize_t nilfs_snapshot_attr_store(struct kobject *kobj, + struct attribute *attr, + const char *buf, size_t len) +{ + struct nilfs_root *root = + container_of(kobj, struct nilfs_root, snapshot_kobj); + struct nilfs_snapshot_attr *a = + container_of(attr, struct nilfs_snapshot_attr, attr); + + return a->store ? a->store(a, root, buf, len) : 0; +} + +static void nilfs_snapshot_attr_release(struct kobject *kobj) +{ + struct nilfs_root *root = container_of(kobj, struct nilfs_root, + snapshot_kobj); + complete(&root->snapshot_kobj_unregister); +} + +static const struct sysfs_ops nilfs_snapshot_attr_ops = { + .show = nilfs_snapshot_attr_show, + .store = nilfs_snapshot_attr_store, +}; + +static const struct kobj_type nilfs_snapshot_ktype = { + .default_groups = nilfs_snapshot_groups, + .sysfs_ops = &nilfs_snapshot_attr_ops, + .release = nilfs_snapshot_attr_release, +}; + +int nilfs_sysfs_create_snapshot_group(struct nilfs_root *root) +{ + struct the_nilfs *nilfs; + struct kobject *parent; + int err; + + nilfs = root->nilfs; + parent = &nilfs->ns_dev_subgroups->sg_mounted_snapshots_kobj; + root->snapshot_kobj.kset = nilfs_kset; + init_completion(&root->snapshot_kobj_unregister); + + if (root->cno == NILFS_CPTREE_CURRENT_CNO) { + err = kobject_init_and_add(&root->snapshot_kobj, + &nilfs_snapshot_ktype, + &nilfs->ns_dev_kobj, + "current_checkpoint"); + } else { + err = kobject_init_and_add(&root->snapshot_kobj, + &nilfs_snapshot_ktype, + parent, + "%llu", root->cno); + } + + if (err) + kobject_put(&root->snapshot_kobj); + + return err; +} + +void nilfs_sysfs_delete_snapshot_group(struct nilfs_root *root) +{ + kobject_put(&root->snapshot_kobj); +} + +/************************************************************************ + * NILFS mounted snapshots attrs * + ************************************************************************/ + +static const char mounted_snapshots_readme_str[] = + "The mounted_snapshots group contains group for\n" + "every mounted snapshot.\n"; + +static ssize_t +nilfs_mounted_snapshots_README_show(struct nilfs_mounted_snapshots_attr *attr, + struct the_nilfs *nilfs, char *buf) +{ + return sysfs_emit(buf, mounted_snapshots_readme_str); +} + +NILFS_MOUNTED_SNAPSHOTS_RO_ATTR(README); + +static struct attribute *nilfs_mounted_snapshots_attrs[] = { + NILFS_MOUNTED_SNAPSHOTS_ATTR_LIST(README), + NULL, +}; +ATTRIBUTE_GROUPS(nilfs_mounted_snapshots); + +NILFS_DEV_INT_GROUP_OPS(mounted_snapshots, dev); +NILFS_DEV_INT_GROUP_TYPE(mounted_snapshots, dev); +NILFS_DEV_INT_GROUP_FNS(mounted_snapshots, dev); + +/************************************************************************ + * NILFS checkpoints attrs * + ************************************************************************/ + +static ssize_t +nilfs_checkpoints_checkpoints_number_show(struct nilfs_checkpoints_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + __u64 ncheckpoints; + struct nilfs_cpstat cpstat; + int err; + + down_read(&nilfs->ns_segctor_sem); + err = nilfs_cpfile_get_stat(nilfs->ns_cpfile, &cpstat); + up_read(&nilfs->ns_segctor_sem); + if (err < 0) { + nilfs_err(nilfs->ns_sb, "unable to get checkpoint stat: err=%d", + err); + return err; + } + + ncheckpoints = cpstat.cs_ncps; + + return sysfs_emit(buf, "%llu\n", ncheckpoints); +} + +static ssize_t +nilfs_checkpoints_snapshots_number_show(struct nilfs_checkpoints_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + __u64 nsnapshots; + struct nilfs_cpstat cpstat; + int err; + + down_read(&nilfs->ns_segctor_sem); + err = nilfs_cpfile_get_stat(nilfs->ns_cpfile, &cpstat); + up_read(&nilfs->ns_segctor_sem); + if (err < 0) { + nilfs_err(nilfs->ns_sb, "unable to get checkpoint stat: err=%d", + err); + return err; + } + + nsnapshots = cpstat.cs_nsss; + + return sysfs_emit(buf, "%llu\n", nsnapshots); +} + +static ssize_t +nilfs_checkpoints_last_seg_checkpoint_show(struct nilfs_checkpoints_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + __u64 last_cno; + + spin_lock(&nilfs->ns_last_segment_lock); + last_cno = nilfs->ns_last_cno; + spin_unlock(&nilfs->ns_last_segment_lock); + + return sysfs_emit(buf, "%llu\n", last_cno); +} + +static ssize_t +nilfs_checkpoints_next_checkpoint_show(struct nilfs_checkpoints_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + __u64 cno; + + down_read(&nilfs->ns_segctor_sem); + cno = nilfs->ns_cno; + up_read(&nilfs->ns_segctor_sem); + + return sysfs_emit(buf, "%llu\n", cno); +} + +static const char checkpoints_readme_str[] = + "The checkpoints group contains attributes that describe\n" + "details about volume's checkpoints.\n\n" + "(1) checkpoints_number\n\tshow number of checkpoints on volume.\n\n" + "(2) snapshots_number\n\tshow number of snapshots on volume.\n\n" + "(3) last_seg_checkpoint\n" + "\tshow checkpoint number of the latest segment.\n\n" + "(4) next_checkpoint\n\tshow next checkpoint number.\n\n"; + +static ssize_t +nilfs_checkpoints_README_show(struct nilfs_checkpoints_attr *attr, + struct the_nilfs *nilfs, char *buf) +{ + return sysfs_emit(buf, checkpoints_readme_str); +} + +NILFS_CHECKPOINTS_RO_ATTR(checkpoints_number); +NILFS_CHECKPOINTS_RO_ATTR(snapshots_number); +NILFS_CHECKPOINTS_RO_ATTR(last_seg_checkpoint); +NILFS_CHECKPOINTS_RO_ATTR(next_checkpoint); +NILFS_CHECKPOINTS_RO_ATTR(README); + +static struct attribute *nilfs_checkpoints_attrs[] = { + NILFS_CHECKPOINTS_ATTR_LIST(checkpoints_number), + NILFS_CHECKPOINTS_ATTR_LIST(snapshots_number), + NILFS_CHECKPOINTS_ATTR_LIST(last_seg_checkpoint), + NILFS_CHECKPOINTS_ATTR_LIST(next_checkpoint), + NILFS_CHECKPOINTS_ATTR_LIST(README), + NULL, +}; +ATTRIBUTE_GROUPS(nilfs_checkpoints); + +NILFS_DEV_INT_GROUP_OPS(checkpoints, dev); +NILFS_DEV_INT_GROUP_TYPE(checkpoints, dev); +NILFS_DEV_INT_GROUP_FNS(checkpoints, dev); + +/************************************************************************ + * NILFS segments attrs * + ************************************************************************/ + +static ssize_t +nilfs_segments_segments_number_show(struct nilfs_segments_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + return sysfs_emit(buf, "%lu\n", nilfs->ns_nsegments); +} + +static ssize_t +nilfs_segments_blocks_per_segment_show(struct nilfs_segments_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + return sysfs_emit(buf, "%lu\n", nilfs->ns_blocks_per_segment); +} + +static ssize_t +nilfs_segments_clean_segments_show(struct nilfs_segments_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + unsigned long ncleansegs; + + down_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem); + ncleansegs = nilfs_sufile_get_ncleansegs(nilfs->ns_sufile); + up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem); + + return sysfs_emit(buf, "%lu\n", ncleansegs); +} + +static ssize_t +nilfs_segments_dirty_segments_show(struct nilfs_segments_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + struct nilfs_sustat sustat; + int err; + + down_read(&nilfs->ns_segctor_sem); + err = nilfs_sufile_get_stat(nilfs->ns_sufile, &sustat); + up_read(&nilfs->ns_segctor_sem); + if (err < 0) { + nilfs_err(nilfs->ns_sb, "unable to get segment stat: err=%d", + err); + return err; + } + + return sysfs_emit(buf, "%llu\n", sustat.ss_ndirtysegs); +} + +static const char segments_readme_str[] = + "The segments group contains attributes that describe\n" + "details about volume's segments.\n\n" + "(1) segments_number\n\tshow number of segments on volume.\n\n" + "(2) blocks_per_segment\n\tshow number of blocks in segment.\n\n" + "(3) clean_segments\n\tshow count of clean segments.\n\n" + "(4) dirty_segments\n\tshow count of dirty segments.\n\n"; + +static ssize_t +nilfs_segments_README_show(struct nilfs_segments_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + return sysfs_emit(buf, segments_readme_str); +} + +NILFS_SEGMENTS_RO_ATTR(segments_number); +NILFS_SEGMENTS_RO_ATTR(blocks_per_segment); +NILFS_SEGMENTS_RO_ATTR(clean_segments); +NILFS_SEGMENTS_RO_ATTR(dirty_segments); +NILFS_SEGMENTS_RO_ATTR(README); + +static struct attribute *nilfs_segments_attrs[] = { + NILFS_SEGMENTS_ATTR_LIST(segments_number), + NILFS_SEGMENTS_ATTR_LIST(blocks_per_segment), + NILFS_SEGMENTS_ATTR_LIST(clean_segments), + NILFS_SEGMENTS_ATTR_LIST(dirty_segments), + NILFS_SEGMENTS_ATTR_LIST(README), + NULL, +}; +ATTRIBUTE_GROUPS(nilfs_segments); + +NILFS_DEV_INT_GROUP_OPS(segments, dev); +NILFS_DEV_INT_GROUP_TYPE(segments, dev); +NILFS_DEV_INT_GROUP_FNS(segments, dev); + +/************************************************************************ + * NILFS segctor attrs * + ************************************************************************/ + +static ssize_t +nilfs_segctor_last_pseg_block_show(struct nilfs_segctor_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + sector_t last_pseg; + + spin_lock(&nilfs->ns_last_segment_lock); + last_pseg = nilfs->ns_last_pseg; + spin_unlock(&nilfs->ns_last_segment_lock); + + return sysfs_emit(buf, "%llu\n", + (unsigned long long)last_pseg); +} + +static ssize_t +nilfs_segctor_last_seg_sequence_show(struct nilfs_segctor_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + u64 last_seq; + + spin_lock(&nilfs->ns_last_segment_lock); + last_seq = nilfs->ns_last_seq; + spin_unlock(&nilfs->ns_last_segment_lock); + + return sysfs_emit(buf, "%llu\n", last_seq); +} + +static ssize_t +nilfs_segctor_last_seg_checkpoint_show(struct nilfs_segctor_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + __u64 last_cno; + + spin_lock(&nilfs->ns_last_segment_lock); + last_cno = nilfs->ns_last_cno; + spin_unlock(&nilfs->ns_last_segment_lock); + + return sysfs_emit(buf, "%llu\n", last_cno); +} + +static ssize_t +nilfs_segctor_current_seg_sequence_show(struct nilfs_segctor_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + u64 seg_seq; + + down_read(&nilfs->ns_segctor_sem); + seg_seq = nilfs->ns_seg_seq; + up_read(&nilfs->ns_segctor_sem); + + return sysfs_emit(buf, "%llu\n", seg_seq); +} + +static ssize_t +nilfs_segctor_current_last_full_seg_show(struct nilfs_segctor_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + __u64 segnum; + + down_read(&nilfs->ns_segctor_sem); + segnum = nilfs->ns_segnum; + up_read(&nilfs->ns_segctor_sem); + + return sysfs_emit(buf, "%llu\n", segnum); +} + +static ssize_t +nilfs_segctor_next_full_seg_show(struct nilfs_segctor_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + __u64 nextnum; + + down_read(&nilfs->ns_segctor_sem); + nextnum = nilfs->ns_nextnum; + up_read(&nilfs->ns_segctor_sem); + + return sysfs_emit(buf, "%llu\n", nextnum); +} + +static ssize_t +nilfs_segctor_next_pseg_offset_show(struct nilfs_segctor_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + unsigned long pseg_offset; + + down_read(&nilfs->ns_segctor_sem); + pseg_offset = nilfs->ns_pseg_offset; + up_read(&nilfs->ns_segctor_sem); + + return sysfs_emit(buf, "%lu\n", pseg_offset); +} + +static ssize_t +nilfs_segctor_next_checkpoint_show(struct nilfs_segctor_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + __u64 cno; + + down_read(&nilfs->ns_segctor_sem); + cno = nilfs->ns_cno; + up_read(&nilfs->ns_segctor_sem); + + return sysfs_emit(buf, "%llu\n", cno); +} + +static ssize_t +nilfs_segctor_last_seg_write_time_show(struct nilfs_segctor_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + time64_t ctime; + + down_read(&nilfs->ns_segctor_sem); + ctime = nilfs->ns_ctime; + up_read(&nilfs->ns_segctor_sem); + + return sysfs_emit(buf, "%ptTs\n", &ctime); +} + +static ssize_t +nilfs_segctor_last_seg_write_time_secs_show(struct nilfs_segctor_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + time64_t ctime; + + down_read(&nilfs->ns_segctor_sem); + ctime = nilfs->ns_ctime; + up_read(&nilfs->ns_segctor_sem); + + return sysfs_emit(buf, "%llu\n", ctime); +} + +static ssize_t +nilfs_segctor_last_nongc_write_time_show(struct nilfs_segctor_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + time64_t nongc_ctime; + + down_read(&nilfs->ns_segctor_sem); + nongc_ctime = nilfs->ns_nongc_ctime; + up_read(&nilfs->ns_segctor_sem); + + return sysfs_emit(buf, "%ptTs\n", &nongc_ctime); +} + +static ssize_t +nilfs_segctor_last_nongc_write_time_secs_show(struct nilfs_segctor_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + time64_t nongc_ctime; + + down_read(&nilfs->ns_segctor_sem); + nongc_ctime = nilfs->ns_nongc_ctime; + up_read(&nilfs->ns_segctor_sem); + + return sysfs_emit(buf, "%llu\n", nongc_ctime); +} + +static ssize_t +nilfs_segctor_dirty_data_blocks_count_show(struct nilfs_segctor_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + u32 ndirtyblks; + + down_read(&nilfs->ns_segctor_sem); + ndirtyblks = atomic_read(&nilfs->ns_ndirtyblks); + up_read(&nilfs->ns_segctor_sem); + + return sysfs_emit(buf, "%u\n", ndirtyblks); +} + +static const char segctor_readme_str[] = + "The segctor group contains attributes that describe\n" + "segctor thread activity details.\n\n" + "(1) last_pseg_block\n" + "\tshow start block number of the latest segment.\n\n" + "(2) last_seg_sequence\n" + "\tshow sequence value of the latest segment.\n\n" + "(3) last_seg_checkpoint\n" + "\tshow checkpoint number of the latest segment.\n\n" + "(4) current_seg_sequence\n\tshow segment sequence counter.\n\n" + "(5) current_last_full_seg\n" + "\tshow index number of the latest full segment.\n\n" + "(6) next_full_seg\n" + "\tshow index number of the full segment index to be used next.\n\n" + "(7) next_pseg_offset\n" + "\tshow offset of next partial segment in the current full segment.\n\n" + "(8) next_checkpoint\n\tshow next checkpoint number.\n\n" + "(9) last_seg_write_time\n" + "\tshow write time of the last segment in human-readable format.\n\n" + "(10) last_seg_write_time_secs\n" + "\tshow write time of the last segment in seconds.\n\n" + "(11) last_nongc_write_time\n" + "\tshow write time of the last segment not for cleaner operation " + "in human-readable format.\n\n" + "(12) last_nongc_write_time_secs\n" + "\tshow write time of the last segment not for cleaner operation " + "in seconds.\n\n" + "(13) dirty_data_blocks_count\n" + "\tshow number of dirty data blocks.\n\n"; + +static ssize_t +nilfs_segctor_README_show(struct nilfs_segctor_attr *attr, + struct the_nilfs *nilfs, char *buf) +{ + return sysfs_emit(buf, segctor_readme_str); +} + +NILFS_SEGCTOR_RO_ATTR(last_pseg_block); +NILFS_SEGCTOR_RO_ATTR(last_seg_sequence); +NILFS_SEGCTOR_RO_ATTR(last_seg_checkpoint); +NILFS_SEGCTOR_RO_ATTR(current_seg_sequence); +NILFS_SEGCTOR_RO_ATTR(current_last_full_seg); +NILFS_SEGCTOR_RO_ATTR(next_full_seg); +NILFS_SEGCTOR_RO_ATTR(next_pseg_offset); +NILFS_SEGCTOR_RO_ATTR(next_checkpoint); +NILFS_SEGCTOR_RO_ATTR(last_seg_write_time); +NILFS_SEGCTOR_RO_ATTR(last_seg_write_time_secs); +NILFS_SEGCTOR_RO_ATTR(last_nongc_write_time); +NILFS_SEGCTOR_RO_ATTR(last_nongc_write_time_secs); +NILFS_SEGCTOR_RO_ATTR(dirty_data_blocks_count); +NILFS_SEGCTOR_RO_ATTR(README); + +static struct attribute *nilfs_segctor_attrs[] = { + NILFS_SEGCTOR_ATTR_LIST(last_pseg_block), + NILFS_SEGCTOR_ATTR_LIST(last_seg_sequence), + NILFS_SEGCTOR_ATTR_LIST(last_seg_checkpoint), + NILFS_SEGCTOR_ATTR_LIST(current_seg_sequence), + NILFS_SEGCTOR_ATTR_LIST(current_last_full_seg), + NILFS_SEGCTOR_ATTR_LIST(next_full_seg), + NILFS_SEGCTOR_ATTR_LIST(next_pseg_offset), + NILFS_SEGCTOR_ATTR_LIST(next_checkpoint), + NILFS_SEGCTOR_ATTR_LIST(last_seg_write_time), + NILFS_SEGCTOR_ATTR_LIST(last_seg_write_time_secs), + NILFS_SEGCTOR_ATTR_LIST(last_nongc_write_time), + NILFS_SEGCTOR_ATTR_LIST(last_nongc_write_time_secs), + NILFS_SEGCTOR_ATTR_LIST(dirty_data_blocks_count), + NILFS_SEGCTOR_ATTR_LIST(README), + NULL, +}; +ATTRIBUTE_GROUPS(nilfs_segctor); + +NILFS_DEV_INT_GROUP_OPS(segctor, dev); +NILFS_DEV_INT_GROUP_TYPE(segctor, dev); +NILFS_DEV_INT_GROUP_FNS(segctor, dev); + +/************************************************************************ + * NILFS superblock attrs * + ************************************************************************/ + +static ssize_t +nilfs_superblock_sb_write_time_show(struct nilfs_superblock_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + time64_t sbwtime; + + down_read(&nilfs->ns_sem); + sbwtime = nilfs->ns_sbwtime; + up_read(&nilfs->ns_sem); + + return sysfs_emit(buf, "%ptTs\n", &sbwtime); +} + +static ssize_t +nilfs_superblock_sb_write_time_secs_show(struct nilfs_superblock_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + time64_t sbwtime; + + down_read(&nilfs->ns_sem); + sbwtime = nilfs->ns_sbwtime; + up_read(&nilfs->ns_sem); + + return sysfs_emit(buf, "%llu\n", sbwtime); +} + +static ssize_t +nilfs_superblock_sb_write_count_show(struct nilfs_superblock_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + unsigned int sbwcount; + + down_read(&nilfs->ns_sem); + sbwcount = nilfs->ns_sbwcount; + up_read(&nilfs->ns_sem); + + return sysfs_emit(buf, "%u\n", sbwcount); +} + +static ssize_t +nilfs_superblock_sb_update_frequency_show(struct nilfs_superblock_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + unsigned int sb_update_freq; + + down_read(&nilfs->ns_sem); + sb_update_freq = nilfs->ns_sb_update_freq; + up_read(&nilfs->ns_sem); + + return sysfs_emit(buf, "%u\n", sb_update_freq); +} + +static ssize_t +nilfs_superblock_sb_update_frequency_store(struct nilfs_superblock_attr *attr, + struct the_nilfs *nilfs, + const char *buf, size_t count) +{ + unsigned int val; + int err; + + err = kstrtouint(skip_spaces(buf), 0, &val); + if (err) { + nilfs_err(nilfs->ns_sb, "unable to convert string: err=%d", + err); + return err; + } + + if (val < NILFS_SB_FREQ) { + val = NILFS_SB_FREQ; + nilfs_warn(nilfs->ns_sb, + "superblock update frequency cannot be lesser than 10 seconds"); + } + + down_write(&nilfs->ns_sem); + nilfs->ns_sb_update_freq = val; + up_write(&nilfs->ns_sem); + + return count; +} + +static const char sb_readme_str[] = + "The superblock group contains attributes that describe\n" + "superblock's details.\n\n" + "(1) sb_write_time\n\tshow previous write time of super block " + "in human-readable format.\n\n" + "(2) sb_write_time_secs\n\tshow previous write time of super block " + "in seconds.\n\n" + "(3) sb_write_count\n\tshow write count of super block.\n\n" + "(4) sb_update_frequency\n" + "\tshow/set interval of periodical update of superblock (in seconds).\n\n" + "\tYou can set preferable frequency of superblock update by command:\n\n" + "\t'echo > /sys/fs///superblock/sb_update_frequency'\n"; + +static ssize_t +nilfs_superblock_README_show(struct nilfs_superblock_attr *attr, + struct the_nilfs *nilfs, char *buf) +{ + return sysfs_emit(buf, sb_readme_str); +} + +NILFS_SUPERBLOCK_RO_ATTR(sb_write_time); +NILFS_SUPERBLOCK_RO_ATTR(sb_write_time_secs); +NILFS_SUPERBLOCK_RO_ATTR(sb_write_count); +NILFS_SUPERBLOCK_RW_ATTR(sb_update_frequency); +NILFS_SUPERBLOCK_RO_ATTR(README); + +static struct attribute *nilfs_superblock_attrs[] = { + NILFS_SUPERBLOCK_ATTR_LIST(sb_write_time), + NILFS_SUPERBLOCK_ATTR_LIST(sb_write_time_secs), + NILFS_SUPERBLOCK_ATTR_LIST(sb_write_count), + NILFS_SUPERBLOCK_ATTR_LIST(sb_update_frequency), + NILFS_SUPERBLOCK_ATTR_LIST(README), + NULL, +}; +ATTRIBUTE_GROUPS(nilfs_superblock); + +NILFS_DEV_INT_GROUP_OPS(superblock, dev); +NILFS_DEV_INT_GROUP_TYPE(superblock, dev); +NILFS_DEV_INT_GROUP_FNS(superblock, dev); + +/************************************************************************ + * NILFS device attrs * + ************************************************************************/ + +static +ssize_t nilfs_dev_revision_show(struct nilfs_dev_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + struct nilfs_super_block *raw_sb; + u32 major; + u16 minor; + + down_read(&nilfs->ns_sem); + raw_sb = nilfs->ns_sbp[0]; + major = le32_to_cpu(raw_sb->s_rev_level); + minor = le16_to_cpu(raw_sb->s_minor_rev_level); + up_read(&nilfs->ns_sem); + + return sysfs_emit(buf, "%d.%d\n", major, minor); +} + +static +ssize_t nilfs_dev_blocksize_show(struct nilfs_dev_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + return sysfs_emit(buf, "%u\n", nilfs->ns_blocksize); +} + +static +ssize_t nilfs_dev_device_size_show(struct nilfs_dev_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + struct nilfs_super_block *raw_sb; + u64 dev_size; + + down_read(&nilfs->ns_sem); + raw_sb = nilfs->ns_sbp[0]; + dev_size = le64_to_cpu(raw_sb->s_dev_size); + up_read(&nilfs->ns_sem); + + return sysfs_emit(buf, "%llu\n", dev_size); +} + +static +ssize_t nilfs_dev_free_blocks_show(struct nilfs_dev_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + sector_t free_blocks = 0; + + nilfs_count_free_blocks(nilfs, &free_blocks); + return sysfs_emit(buf, "%llu\n", + (unsigned long long)free_blocks); +} + +static +ssize_t nilfs_dev_uuid_show(struct nilfs_dev_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + struct nilfs_super_block *raw_sb; + ssize_t len; + + down_read(&nilfs->ns_sem); + raw_sb = nilfs->ns_sbp[0]; + len = sysfs_emit(buf, "%pUb\n", raw_sb->s_uuid); + up_read(&nilfs->ns_sem); + + return len; +} + +static +ssize_t nilfs_dev_volume_name_show(struct nilfs_dev_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + struct nilfs_super_block *raw_sb; + ssize_t len; + + down_read(&nilfs->ns_sem); + raw_sb = nilfs->ns_sbp[0]; + len = scnprintf(buf, sizeof(raw_sb->s_volume_name), "%s\n", + raw_sb->s_volume_name); + up_read(&nilfs->ns_sem); + + return len; +} + +static const char dev_readme_str[] = + "The group contains attributes that describe file system\n" + "partition's details.\n\n" + "(1) revision\n\tshow NILFS file system revision.\n\n" + "(2) blocksize\n\tshow volume block size in bytes.\n\n" + "(3) device_size\n\tshow volume size in bytes.\n\n" + "(4) free_blocks\n\tshow count of free blocks on volume.\n\n" + "(5) uuid\n\tshow volume's UUID.\n\n" + "(6) volume_name\n\tshow volume's name.\n\n"; + +static ssize_t nilfs_dev_README_show(struct nilfs_dev_attr *attr, + struct the_nilfs *nilfs, + char *buf) +{ + return sysfs_emit(buf, dev_readme_str); +} + +NILFS_DEV_RO_ATTR(revision); +NILFS_DEV_RO_ATTR(blocksize); +NILFS_DEV_RO_ATTR(device_size); +NILFS_DEV_RO_ATTR(free_blocks); +NILFS_DEV_RO_ATTR(uuid); +NILFS_DEV_RO_ATTR(volume_name); +NILFS_DEV_RO_ATTR(README); + +static struct attribute *nilfs_dev_attrs[] = { + NILFS_DEV_ATTR_LIST(revision), + NILFS_DEV_ATTR_LIST(blocksize), + NILFS_DEV_ATTR_LIST(device_size), + NILFS_DEV_ATTR_LIST(free_blocks), + NILFS_DEV_ATTR_LIST(uuid), + NILFS_DEV_ATTR_LIST(volume_name), + NILFS_DEV_ATTR_LIST(README), + NULL, +}; +ATTRIBUTE_GROUPS(nilfs_dev); + +static ssize_t nilfs_dev_attr_show(struct kobject *kobj, + struct attribute *attr, char *buf) +{ + struct the_nilfs *nilfs = container_of(kobj, struct the_nilfs, + ns_dev_kobj); + struct nilfs_dev_attr *a = container_of(attr, struct nilfs_dev_attr, + attr); + + return a->show ? a->show(a, nilfs, buf) : 0; +} + +static ssize_t nilfs_dev_attr_store(struct kobject *kobj, + struct attribute *attr, + const char *buf, size_t len) +{ + struct the_nilfs *nilfs = container_of(kobj, struct the_nilfs, + ns_dev_kobj); + struct nilfs_dev_attr *a = container_of(attr, struct nilfs_dev_attr, + attr); + + return a->store ? a->store(a, nilfs, buf, len) : 0; +} + +static void nilfs_dev_attr_release(struct kobject *kobj) +{ + struct the_nilfs *nilfs = container_of(kobj, struct the_nilfs, + ns_dev_kobj); + complete(&nilfs->ns_dev_kobj_unregister); +} + +static const struct sysfs_ops nilfs_dev_attr_ops = { + .show = nilfs_dev_attr_show, + .store = nilfs_dev_attr_store, +}; + +static const struct kobj_type nilfs_dev_ktype = { + .default_groups = nilfs_dev_groups, + .sysfs_ops = &nilfs_dev_attr_ops, + .release = nilfs_dev_attr_release, +}; + +int nilfs_sysfs_create_device_group(struct super_block *sb) +{ + struct the_nilfs *nilfs = sb->s_fs_info; + size_t devgrp_size = sizeof(struct nilfs_sysfs_dev_subgroups); + int err; + + nilfs->ns_dev_subgroups = kzalloc(devgrp_size, GFP_KERNEL); + if (unlikely(!nilfs->ns_dev_subgroups)) { + err = -ENOMEM; + nilfs_err(sb, "unable to allocate memory for device group"); + goto failed_create_device_group; + } + + nilfs->ns_dev_kobj.kset = nilfs_kset; + init_completion(&nilfs->ns_dev_kobj_unregister); + err = kobject_init_and_add(&nilfs->ns_dev_kobj, &nilfs_dev_ktype, NULL, + "%s", sb->s_id); + if (err) + goto cleanup_dev_kobject; + + err = nilfs_sysfs_create_mounted_snapshots_group(nilfs); + if (err) + goto cleanup_dev_kobject; + + err = nilfs_sysfs_create_checkpoints_group(nilfs); + if (err) + goto delete_mounted_snapshots_group; + + err = nilfs_sysfs_create_segments_group(nilfs); + if (err) + goto delete_checkpoints_group; + + err = nilfs_sysfs_create_superblock_group(nilfs); + if (err) + goto delete_segments_group; + + err = nilfs_sysfs_create_segctor_group(nilfs); + if (err) + goto delete_superblock_group; + + return 0; + +delete_superblock_group: + nilfs_sysfs_delete_superblock_group(nilfs); + +delete_segments_group: + nilfs_sysfs_delete_segments_group(nilfs); + +delete_checkpoints_group: + nilfs_sysfs_delete_checkpoints_group(nilfs); + +delete_mounted_snapshots_group: + nilfs_sysfs_delete_mounted_snapshots_group(nilfs); + +cleanup_dev_kobject: + kobject_put(&nilfs->ns_dev_kobj); + kfree(nilfs->ns_dev_subgroups); + +failed_create_device_group: + return err; +} + +void nilfs_sysfs_delete_device_group(struct the_nilfs *nilfs) +{ + nilfs_sysfs_delete_mounted_snapshots_group(nilfs); + nilfs_sysfs_delete_checkpoints_group(nilfs); + nilfs_sysfs_delete_segments_group(nilfs); + nilfs_sysfs_delete_superblock_group(nilfs); + nilfs_sysfs_delete_segctor_group(nilfs); + kobject_del(&nilfs->ns_dev_kobj); + kobject_put(&nilfs->ns_dev_kobj); + kfree(nilfs->ns_dev_subgroups); +} + +/************************************************************************ + * NILFS feature attrs * + ************************************************************************/ + +static ssize_t nilfs_feature_revision_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + return sysfs_emit(buf, "%d.%d\n", + NILFS_CURRENT_REV, NILFS_MINOR_REV); +} + +static const char features_readme_str[] = + "The features group contains attributes that describe NILFS file\n" + "system driver features.\n\n" + "(1) revision\n\tshow current revision of NILFS file system driver.\n"; + +static ssize_t nilfs_feature_README_show(struct kobject *kobj, + struct kobj_attribute *attr, + char *buf) +{ + return sysfs_emit(buf, features_readme_str); +} + +NILFS_FEATURE_RO_ATTR(revision); +NILFS_FEATURE_RO_ATTR(README); + +static struct attribute *nilfs_feature_attrs[] = { + NILFS_FEATURE_ATTR_LIST(revision), + NILFS_FEATURE_ATTR_LIST(README), + NULL, +}; + +static const struct attribute_group nilfs_feature_attr_group = { + .name = "features", + .attrs = nilfs_feature_attrs, +}; + +int __init nilfs_sysfs_init(void) +{ + int err; + + nilfs_kset = kset_create_and_add(NILFS_ROOT_GROUP_NAME, NULL, fs_kobj); + if (!nilfs_kset) { + err = -ENOMEM; + nilfs_err(NULL, "unable to create sysfs entry: err=%d", err); + goto failed_sysfs_init; + } + + err = sysfs_create_group(&nilfs_kset->kobj, &nilfs_feature_attr_group); + if (unlikely(err)) { + nilfs_err(NULL, "unable to create feature group: err=%d", err); + goto cleanup_sysfs_init; + } + + return 0; + +cleanup_sysfs_init: + kset_unregister(nilfs_kset); + +failed_sysfs_init: + return err; +} + +void nilfs_sysfs_exit(void) +{ + sysfs_remove_group(&nilfs_kset->kobj, &nilfs_feature_attr_group); + kset_unregister(nilfs_kset); +} -- cgit v1.3.1