From c067da87815657779115b8eae01c514458e4dfd2 Mon Sep 17 00:00:00 2001 From: Sweet Tea Dorminy Date: Wed, 23 Feb 2022 14:38:06 -0500 Subject: btrfs: add filesystems state details to error messages When a filesystem goes read-only due to an error, multiple errors tend to be reported, some of which are knock-on failures. Logging fs_states, in btrfs_handle_fs_error() and btrfs_printk() helps distinguish the first error from subsequent messages which may only exist due to an error state. Under the new format, most initial errors will look like: `BTRFS: error (device loop0) in ...` while subsequent errors will begin with: `error (device loop0: state E) in ...` An initial transaction abort error will look like `error (device loop0: state A) in ...` and subsequent messages will contain `(device loop0: state EA) in ...` In addition to the error states we can also print other states that are temporary, like remounting, device replace, or indicate a global state that may affect functionality. Now implemented: E - filesystem error detected A - transaction aborted L - log tree errors M - remounting in progress R - device replace in progress C - data checksums not verified (mounted with ignoredatacsums) Signed-off-by: Sweet Tea Dorminy Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/ctree.h | 2 ++ fs/btrfs/super.c | 68 +++++++++++++++++++++++++++++++++++++++++++++++++------- 2 files changed, 62 insertions(+), 8 deletions(-) diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 5745b37a7e55..8e79e3ded882 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -149,6 +149,8 @@ enum { /* Indicates there was an error cleaning up a log tree. */ BTRFS_FS_STATE_LOG_CLEANUP_ERROR, + + BTRFS_FS_STATE_COUNT }; #define BTRFS_BACKREF_REV_MAX 256 diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 33cfc9e27451..b228efe8ab6e 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -66,6 +66,52 @@ static struct file_system_type btrfs_root_fs_type; static int btrfs_remount(struct super_block *sb, int *flags, char *data); +#ifdef CONFIG_PRINTK + +#define STATE_STRING_PREFACE ": state " +#define STATE_STRING_BUF_LEN (sizeof(STATE_STRING_PREFACE) + BTRFS_FS_STATE_COUNT) + +/* + * Characters to print to indicate error conditions or uncommon filesystem sate. + * RO is not an error. + */ +static const char fs_state_chars[] = { + [BTRFS_FS_STATE_ERROR] = 'E', + [BTRFS_FS_STATE_REMOUNTING] = 'M', + [BTRFS_FS_STATE_RO] = 0, + [BTRFS_FS_STATE_TRANS_ABORTED] = 'A', + [BTRFS_FS_STATE_DEV_REPLACING] = 'R', + [BTRFS_FS_STATE_DUMMY_FS_INFO] = 0, + [BTRFS_FS_STATE_NO_CSUMS] = 'C', + [BTRFS_FS_STATE_LOG_CLEANUP_ERROR] = 'L', +}; + +static void btrfs_state_to_string(const struct btrfs_fs_info *info, char *buf) +{ + unsigned int bit; + bool states_printed = false; + unsigned long fs_state = READ_ONCE(info->fs_state); + char *curr = buf; + + memcpy(curr, STATE_STRING_PREFACE, sizeof(STATE_STRING_PREFACE)); + curr += sizeof(STATE_STRING_PREFACE) - 1; + + for_each_set_bit(bit, &fs_state, sizeof(fs_state)) { + WARN_ON_ONCE(bit >= BTRFS_FS_STATE_COUNT); + if ((bit < BTRFS_FS_STATE_COUNT) && fs_state_chars[bit]) { + *curr++ = fs_state_chars[bit]; + states_printed = true; + } + } + + /* If no states were printed, reset the buffer */ + if (!states_printed) + curr = buf; + + *curr++ = 0; +} +#endif + /* * Generally the error codes correspond to their respective errors, but there * are a few special cases. @@ -128,6 +174,7 @@ void __btrfs_handle_fs_error(struct btrfs_fs_info *fs_info, const char *function { struct super_block *sb = fs_info->sb; #ifdef CONFIG_PRINTK + char statestr[STATE_STRING_BUF_LEN]; const char *errstr; #endif @@ -140,6 +187,7 @@ void __btrfs_handle_fs_error(struct btrfs_fs_info *fs_info, const char *function #ifdef CONFIG_PRINTK errstr = btrfs_decode_error(errno); + btrfs_state_to_string(fs_info, statestr); if (fmt) { struct va_format vaf; va_list args; @@ -148,12 +196,12 @@ void __btrfs_handle_fs_error(struct btrfs_fs_info *fs_info, const char *function vaf.fmt = fmt; vaf.va = &args; - pr_crit("BTRFS: error (device %s) in %s:%d: errno=%d %s (%pV)\n", - sb->s_id, function, line, errno, errstr, &vaf); + pr_crit("BTRFS: error (device %s%s) in %s:%d: errno=%d %s (%pV)\n", + sb->s_id, statestr, function, line, errno, errstr, &vaf); va_end(args); } else { - pr_crit("BTRFS: error (device %s) in %s:%d: errno=%d %s\n", - sb->s_id, function, line, errno, errstr); + pr_crit("BTRFS: error (device %s%s) in %s:%d: errno=%d %s\n", + sb->s_id, statestr, function, line, errno, errstr); } #endif @@ -240,11 +288,15 @@ void __cold btrfs_printk(const struct btrfs_fs_info *fs_info, const char *fmt, . vaf.va = &args; if (__ratelimit(ratelimit)) { - if (fs_info) - printk("%sBTRFS %s (device %s): %pV\n", lvl, type, - fs_info->sb->s_id, &vaf); - else + if (fs_info) { + char statestr[STATE_STRING_BUF_LEN]; + + btrfs_state_to_string(fs_info, statestr); + printk("%sBTRFS %s (device %s%s): %pV\n", lvl, type, + fs_info->sb->s_id, statestr, &vaf); + } else { printk("%sBTRFS %s: %pV\n", lvl, type, &vaf); + } } va_end(args); -- cgit v1.2.3