[Kernel] [PATCH OpenHarmony-4.19 32/49] pstore/ftrace: Provide ftrace log merging routine

From: Kees Cook &lt;keescook(a)chromium.org&gt; stable inclusion from stable-5.10 category: feature commit:16a583079e937f6f5e6274ef7fda6dbf7dcb669f issue: #I4919J -------------------------------- Move the ftrace log merging logic out of pstore/ram into pstore/ftrace so other backends can use it, like pstore/zone. Link: https://lore.kernel.org/lkml/20200510202436.63222-7-keescook@chromium.org/ Signed-off-by: Kees Cook &lt;keescook(a)chromium.org&gt; (cherry picked from commit 16a583079e937f6f5e6274ef7fda6dbf7dcb669f) Signed-off-by: roger &lt;kongzhengrong(a)huawei.com&gt; --- fs/pstore/ftrace.c | 54 +++++++++++++++++++++++++++++++++++++++++ fs/pstore/internal.h | 9 +++++++ fs/pstore/ram.c | 57 +++----------------------------------------- 3 files changed, 66 insertions(+), 54 deletions(-) diff --git a/fs/pstore/ftrace.c b/fs/pstore/ftrace.c index fd9468928bef..8a4f05c27205 100644 --- a/fs/pstore/ftrace.c +++ b/fs/pstore/ftrace.c @@ -24,6 +24,7 @@ #include <linux/debugfs.h> #include <linux/err.h> #include <linux/cache.h> +#include <linux/slab.h> #include <asm/barrier.h> #include "internal.h" @@ -140,3 +141,56 @@ void pstore_unregister_ftrace(void) debugfs_remove_recursive(pstore_ftrace_dir); } + +ssize_t pstore_ftrace_combine_log(char **dest_log, size_t *dest_log_size, + const char *src_log, size_t src_log_size) +{ + size_t dest_size, src_size, total, dest_off, src_off; + size_t dest_idx = 0, src_idx = 0, merged_idx = 0; + void *merged_buf; + struct pstore_ftrace_record *drec, *srec, *mrec; + size_t record_size = sizeof(struct pstore_ftrace_record); + + dest_off = *dest_log_size % record_size; + dest_size = *dest_log_size - dest_off; + + src_off = src_log_size % record_size; + src_size = src_log_size - src_off; + + total = dest_size + src_size; + merged_buf = kmalloc(total, GFP_KERNEL); + if (!merged_buf) + return -ENOMEM; + + drec = (struct pstore_ftrace_record *)(*dest_log + dest_off); + srec = (struct pstore_ftrace_record *)(src_log + src_off); + mrec = (struct pstore_ftrace_record *)(merged_buf); + + while (dest_size > 0 && src_size > 0) { + if (pstore_ftrace_read_timestamp(&drec[dest_idx]) < + pstore_ftrace_read_timestamp(&srec[src_idx])) { + mrec[merged_idx++] = drec[dest_idx++]; + dest_size -= record_size; + } else { + mrec[merged_idx++] = srec[src_idx++]; + src_size -= record_size; + } + } + + while (dest_size > 0) { + mrec[merged_idx++] = drec[dest_idx++]; + dest_size -= record_size; + } + + while (src_size > 0) { + mrec[merged_idx++] = srec[src_idx++]; + src_size -= record_size; + } + + kfree(*dest_log); + *dest_log = merged_buf; + *dest_log_size = total; + + return 0; +} +EXPORT_SYMBOL_GPL(pstore_ftrace_combine_log); diff --git a/fs/pstore/internal.h b/fs/pstore/internal.h index fe5f7ef7323f..7783db28ce4a 100644 --- a/fs/pstore/internal.h +++ b/fs/pstore/internal.h @@ -12,9 +12,18 @@ extern unsigned long kmsg_bytes; #ifdef CONFIG_PSTORE_FTRACE extern void pstore_register_ftrace(void); extern void pstore_unregister_ftrace(void); +ssize_t pstore_ftrace_combine_log(char **dest_log, size_t *dest_log_size, + const char *src_log, size_t src_log_size); #else static inline void pstore_register_ftrace(void) {} static inline void pstore_unregister_ftrace(void) {} +static inline ssize_t +pstore_ftrace_combine_log(char **dest_log, size_t *dest_log_size, + const char *src_log, size_t src_log_size) +{ + *dest_log_size = 0; + return 0; +} #endif #ifdef CONFIG_PSTORE_PMSG diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c index 89bd5d479b33..4c539f5bffa0 100644 --- a/fs/pstore/ram.c +++ b/fs/pstore/ram.c @@ -35,6 +35,7 @@ #include <linux/pstore_ram.h> #include <linux/of.h> #include <linux/of_address.h> +#include "internal.h" #define RAMOOPS_KERNMSG_HDR "====" #define MIN_MEM_SIZE 4096UL @@ -182,59 +183,6 @@ static bool prz_ok(struct persistent_ram_zone *prz) persistent_ram_ecc_string(prz, NULL, 0)); } -static -ssize_t ftrace_log_combine(char **dest_log, size_t *dest_log_size, - const char *src_log, size_t src_log_size) -{ - size_t dest_size, src_size, total, dest_off, src_off; - size_t dest_idx = 0, src_idx = 0, merged_idx = 0; - void *merged_buf; - struct pstore_ftrace_record *drec, *srec, *mrec; - size_t record_size = sizeof(struct pstore_ftrace_record); - - dest_off = *dest_log_size % record_size; - dest_size = *dest_log_size - dest_off; - - src_off = src_log_size % record_size; - src_size = src_log_size - src_off; - - total = dest_size + src_size; - merged_buf = kmalloc(total, GFP_KERNEL); - if (!merged_buf) - return -ENOMEM; - - drec = (struct pstore_ftrace_record *)(*dest_log + dest_off); - srec = (struct pstore_ftrace_record *)(src_log + src_off); - mrec = (struct pstore_ftrace_record *)(merged_buf); - - while (dest_size > 0 && src_size > 0) { - if (pstore_ftrace_read_timestamp(&drec[dest_idx]) < - pstore_ftrace_read_timestamp(&srec[src_idx])) { - mrec[merged_idx++] = drec[dest_idx++]; - dest_size -= record_size; - } else { - mrec[merged_idx++] = srec[src_idx++]; - src_size -= record_size; - } - } - - while (dest_size > 0) { - mrec[merged_idx++] = drec[dest_idx++]; - dest_size -= record_size; - } - - while (src_size > 0) { - mrec[merged_idx++] = srec[src_idx++]; - src_size -= record_size; - } - - kfree(*dest_log); - *dest_log = merged_buf; - *dest_log_size = total; - - return 0; -} - static ssize_t ramoops_pstore_read(struct pstore_record *record) { ssize_t size = 0; @@ -307,7 +255,8 @@ static ssize_t ramoops_pstore_read(struct pstore_record *record) prz_next->corrected_bytes; tmp_prz->bad_blocks += prz_next->bad_blocks; - size = ftrace_log_combine(&tmp_prz->old_log, + size = pstore_ftrace_combine_log( + &tmp_prz->old_log, &tmp_prz->old_log_size, prz_next->old_log, prz_next->old_log_size); -- 2.17.1