From 034dd340b08be1f2f0477ad16131d609f9dbd53c Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 30 Aug 2026 09:22:00 -0700 Subject: Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Fix error output of boot instance creation failure Currently if a boot instance creation fails, instead of printing out the name of the instance that failed, it prints "(null)". That is because it prints "cur_str" that had already been processed by strsep(). Print the saved name instead. While at it, print the error code of the failure. - Fix use-after-free for same named historgrams Histograms can be named so that they can be used in multiple events. But if the named histogram has a variable attached, the second event that uses the named histogram which duplicates it and needs to free the original after duplication leaves the old variable in place and still visible. If another histogram uses than variable, it will use the stale one which will try to reference the freed duplicate histogram and crash the kernel. Free the duplicate variables along with the duplicated histogram data. - Check return value of kthread_run() in event self test The events self tests uses a kthread for testing but does not check if it succeeded in creating a kthread. If the kthread creation were to fail, the code will still try to call kthread_stop() on the error returned. - Fix race between reading trace_pipe and updating subbuffer size If a user is reading the trace_pipe file at the same time they update the ring buffer sub-buffer size, can cause the trace_pipe read to read stale data. Add trace_access_lock() around updating the ring buffer sub-buffer size. - Fix eventfs_inode on failure path in creation of the events directory In the creation of the "events" directory, if after allocating the eventfs_inode a failure is detected, it calls cleanup_ei() which calls free_ei(). The free_ei() will test if eventfs_inode being freed has no children. It is a bug if it does. But on the failure case of the creation of the "events" directory, the children lists have not yet been initialized and the free will trigger a warning because list_empty() on an uninitialized list returns false. Move the initialization into init_ei() where it makes more sense and makes sure that a created eventfs_inode has its lists initialized upon creation. - Check return value of kthread_run() in ftrace direct sample code The sample code that shows how to use the ftrace direct calls does not test the return of kthread_run() to see if it succeeds. Return a failure if the kthread_run() doesn't succeed. - Clear user events state on fork in case of alloc failure On fork, the child gets a pointer to the parent's user events state. It makes a copy of it then updates the child's pointer to it. But if the allocation fails, the duplication function leaves the child with a pointer to its parent's descriptor. When the child cleans up its data, it will free the parent's descriptor while the parent is still using it. In the duplication function, set the child's user_event_mm to NULL before testing if the allocation succeeded, and when it exits it will not free the parent's descriptor. - Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. But the check for success expects the retry value to be non-zero and exits with an error on zero. This is the opposite result. Fix it. - Fail nicely when the remote swap_reader_page() returns an error Currently, if the swap_reader_page() of a remote buffer fails, it triggers a WARN_ON_ONCE() and continues normally. Instead, have it exit with an error and a pr_warn() print instead of a full WARNING. * tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Stop remote reader update when page swap fails tracing: Fix retry exhaustion in simple ring buffer reader swap tracing/user_events: Clear copied tracing state before fork duplication samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify eventfs: Initialize ei->children and ei->list in init_ei() tracing: Fix use-after-free in trace_pipe read on sub-buffer order change tracing: Fix crash passing ERR_PTR to kthread_stop() tracing: Fix use-after-free with same-name named triggers tracing: Fix logged instance name on creation failure --- drivers/md/md-bitmap.h | 208 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 208 insertions(+) create mode 100644 drivers/md/md-bitmap.h (limited to 'drivers/md/md-bitmap.h') diff --git a/drivers/md/md-bitmap.h b/drivers/md/md-bitmap.h new file mode 100644 index 000000000..b69c78174 --- /dev/null +++ b/drivers/md/md-bitmap.h @@ -0,0 +1,208 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * bitmap.h: Copyright (C) Peter T. Breuer (ptb@ot.uc3m.es) 2003 + * + * additions: Copyright (C) 2003-2004, Paul Clements, SteelEye Technology, Inc. + */ +#ifndef BITMAP_H +#define BITMAP_H 1 + +#define BITMAP_MAGIC 0x6d746962 + +/* + * version 3 is host-endian order, this is deprecated and not used for new + * array + */ +#define BITMAP_MAJOR_LO 3 +#define BITMAP_MAJOR_HOSTENDIAN 3 +/* version 4 is little-endian order, the default value */ +#define BITMAP_MAJOR_HI 4 +/* version 5 is only used for cluster */ +#define BITMAP_MAJOR_CLUSTERED 5 +/* version 6 is only used for lockless bitmap */ +#define BITMAP_MAJOR_LOCKLESS 6 + +/* use these for bitmap->flags and bitmap->sb->state bit-fields */ +enum bitmap_state { + BITMAP_STALE = 1, /* the bitmap file is out of date or had -EIO */ + BITMAP_WRITE_ERROR = 2, /* A write error has occurred */ + BITMAP_FIRST_USE = 3, /* llbitmap is just created */ + BITMAP_CLEAN = 4, /* llbitmap is created with assume_clean */ + BITMAP_DAEMON_BUSY = 5, /* llbitmap daemon is not finished after daemon_sleep */ + BITMAP_SHUTDOWN = 6, /* llbitmap is being destroyed */ + BITMAP_HOSTENDIAN =15, +}; + +/* the superblock at the front of the bitmap file -- little endian */ +typedef struct bitmap_super_s { + __le32 magic; /* 0 BITMAP_MAGIC */ + __le32 version; /* 4 the bitmap major for now, could change... */ + __u8 uuid[16]; /* 8 128 bit uuid - must match md device uuid */ + __le64 events; /* 24 event counter for the bitmap (1)*/ + __le64 events_cleared;/*32 event counter when last bit cleared (2) */ + __le64 sync_size; /* 40 the size of the md device's sync range(3) */ + __le32 state; /* 48 bitmap state information */ + __le32 chunksize; /* 52 the bitmap chunk size in bytes */ + __le32 daemon_sleep; /* 56 seconds between disk flushes */ + __le32 write_behind; /* 60 number of outstanding write-behind writes */ + __le32 sectors_reserved; /* 64 number of 512-byte sectors that are + * reserved for the bitmap. */ + __le32 nodes; /* 68 the maximum number of nodes in cluster. */ + __u8 cluster_name[64]; /* 72 cluster name to which this md belongs */ + __u8 pad[256 - 136]; /* set to zero */ +} bitmap_super_t; + +/* notes: + * (1) This event counter is updated before the eventcounter in the md superblock + * When a bitmap is loaded, it is only accepted if this event counter is equal + * to, or one greater than, the event counter in the superblock. + * (2) This event counter is updated when the other one is *if*and*only*if* the + * array is not degraded. As bits are not cleared when the array is degraded, + * this represents the last time that any bits were cleared. + * If a device is being added that has an event count with this value or + * higher, it is accepted as conforming to the bitmap. + * (3)This is the number of sectors represented by the bitmap, and is the range that + * resync happens across. For raid1 and raid5/6 it is the size of individual + * devices. For raid10 it is the size of the array. + */ + +struct md_bitmap_stats { + u64 events_cleared; + int behind_writes; + bool behind_wait; + + unsigned long missing_pages; + unsigned long file_pages; + unsigned long sync_size; + unsigned long pages; + struct file *file; +}; + +typedef void (md_bitmap_fn)(struct mddev *mddev, sector_t offset, + unsigned long sectors); + +struct bitmap_operations { + struct md_submodule_head head; + + bool (*enabled)(void *data, bool flush); + int (*create)(struct mddev *mddev); + int (*resize)(struct mddev *mddev, sector_t blocks, int chunksize); + + int (*load)(struct mddev *mddev); + void (*destroy)(struct mddev *mddev); + void (*flush)(struct mddev *mddev); + void (*write_all)(struct mddev *mddev); + void (*dirty_bits)(struct mddev *mddev, unsigned long s, + unsigned long e); + /* Prepare a range for this bitmap implementation. */ + void (*prepare_range)(struct mddev *mddev, + sector_t *offset, + unsigned long *sectors, + bool discard); + void (*reshape_finish)(struct mddev *mddev); + int (*reshape_can_start)(struct mddev *mddev); + void (*reshape_mark)(struct mddev *mddev, sector_t old_pos, + sector_t new_pos); + void (*unplug)(struct mddev *mddev, bool sync); + void (*daemon_work)(struct mddev *mddev); + + void (*start_behind_write)(struct mddev *mddev); + void (*end_behind_write)(struct mddev *mddev); + void (*wait_behind_writes)(struct mddev *mddev); + + md_bitmap_fn *start_write; + md_bitmap_fn *end_write; + md_bitmap_fn *start_discard; + md_bitmap_fn *end_discard; + + sector_t (*skip_sync_blocks)(struct mddev *mddev, sector_t offset); + bool (*blocks_synced)(struct mddev *mddev, sector_t offset); + bool (*start_sync)(struct mddev *mddev, sector_t offset, + sector_t *blocks, bool degraded); + void (*end_sync)(struct mddev *mddev, sector_t offset, sector_t *blocks); + void (*cond_end_sync)(struct mddev *mddev, sector_t sector, bool force); + void (*close_sync)(struct mddev *mddev); + + void (*update_sb)(void *data); + int (*get_stats)(void *data, struct md_bitmap_stats *stats); + + void (*sync_with_cluster)(struct mddev *mddev, + sector_t old_lo, sector_t old_hi, + sector_t new_lo, sector_t new_hi); + void *(*get_from_slot)(struct mddev *mddev, int slot); + int (*copy_from_slot)(struct mddev *mddev, int slot, sector_t *lo, + sector_t *hi, bool clear_bits); + void (*set_pages)(void *data, unsigned long pages); + void (*free)(void *data); + + const struct attribute_group **groups; +}; + +/* the bitmap API */ +static inline bool md_bitmap_registered(struct mddev *mddev) +{ + return mddev->bitmap_ops != NULL; +} + +static inline bool md_bitmap_enabled(struct mddev *mddev, bool flush) +{ + /* bitmap_ops must be registered before creating bitmap. */ + if (!md_bitmap_registered(mddev)) + return false; + + if (!mddev->bitmap) + return false; + + return mddev->bitmap_ops->enabled(mddev->bitmap, flush); +} + +static inline bool md_bitmap_start_sync(struct mddev *mddev, sector_t offset, + sector_t *blocks, bool degraded) +{ + /* always resync if no bitmap */ + if (!md_bitmap_enabled(mddev, false)) { + *blocks = 1024; + return true; + } + + return mddev->bitmap_ops->start_sync(mddev, offset, blocks, degraded); +} + +static inline void md_bitmap_end_sync(struct mddev *mddev, sector_t offset, + sector_t *blocks) +{ + if (!md_bitmap_enabled(mddev, false)) { + *blocks = 1024; + return; + } + + mddev->bitmap_ops->end_sync(mddev, offset, blocks); +} + +#ifdef CONFIG_MD_BITMAP +int md_bitmap_init(void); +void md_bitmap_exit(void); +#else +static inline int md_bitmap_init(void) +{ + return 0; +} +static inline void md_bitmap_exit(void) +{ +} +#endif + +#ifdef CONFIG_MD_LLBITMAP +int md_llbitmap_init(void); +void md_llbitmap_exit(void); +#else +static inline int md_llbitmap_init(void) +{ + return 0; +} +static inline void md_llbitmap_exit(void) +{ +} +#endif + +#endif -- cgit v1.3.1