/* * c 2001 PPC 64 Team, IBM Corp * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. * * /dev/nvram driver for PPC64 * * This perhaps should live in drivers/char */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* Max bytes to read/write in one go */ #define NVRW_CNT 0x20 /* * Set oops header version to distinguish between old and new format header. * lnx,oops-log partition max size is 4000, header version > 4000 will * help in identifying new header. */ #define OOPS_HDR_VERSION 5000 static unsigned int nvram_size; static int nvram_fetch, nvram_store; static char nvram_buf[NVRW_CNT]; /* assume this is in the first 4GB */ static DEFINE_SPINLOCK(nvram_lock); struct err_log_info { __be32 error_type; __be32 seq_num; }; struct nvram_os_partition { const char *name; int req_size; /* desired size, in bytes */ int min_size; /* minimum acceptable size (0 means req_size) */ long size; /* size of data portion (excluding err_log_info) */ long index; /* offset of data portion of partition */ bool os_partition; /* partition initialized by OS, not FW */ }; static struct nvram_os_partition rtas_log_partition = { .name = "ibm,rtas-log", .req_size = 2079, .min_size = 1055, .index = -1, .os_partition = true }; static struct nvram_os_partition oops_log_partition = { .name = "lnx,oops-log", .req_size = 4000, .min_size = 2000, .index = -1, .os_partition = true }; static const char *pseries_nvram_os_partitions[] = { "ibm,rtas-log", "lnx,oops-log", NULL }; struct oops_log_info { __be16 version; __be16 report_length; __be64 timestamp; } __attribute__((packed)); static void oops_to_nvram(struct kmsg_dumper *dumper, enum kmsg_dump_reason reason); static struct kmsg_dumper nvram_kmsg_dumper = { .dump = oops_to_nvram }; /* See clobbering_unread_rtas_event() */ #define NVRAM_RTAS_READ_TIMEOUT 5 /* seconds */ static unsigned long last_unread_rtas_event; /* timestamp */ /* * For capturing and compressing an oops or panic report... * big_oops_buf[] holds the uncompressed text we're capturing. * * oops_buf[] holds the compressed text, preceded by a oops header. * oops header has u16 holding the version of oops header (to differentiate * between old and new format header) followed by u16 holding the length of * the compressed* text (*Or uncompressed, if compression fails.) and u64 * holding the timestamp. oops_buf[] gets written to NVRAM. * * oops_log_info points to the header. oops_data points to the compressed text. * * +- oops_buf * | +- oops_data * v v * +-----------+-----------+-----------+------------------------+ * | version | length | timestamp | text | * | (2 bytes) | (2 bytes) | (8 bytes) | (oops_data_sz bytes) | * +-----------+-----------+-----------+------------------------+ * ^ * +- oops_log_info * * We preallocate these buffers during init to avoid kmalloc during oops/panic. */ static size_t big_oops_buf_sz; static char *big_oops_buf, *oops_buf; static char *oops_data; static size_t oops_data_sz; /* Compression parameters */ #define COMPR_LEVEL 6 #define WINDOW_BITS 12 #define MEM_LEVEL 4 static struct z_stream_s stream; #ifdef CONFIG_PSTORE static struct nvram_os_partition of_config_partition = { .name = "of-config", .index = -1, .os_partition = false }; static struct nvram_os_partition common_partition = { .name = "common", .index = -1, .os_partition = false }; static enum pstore_type_id nvram_type_ids[] = { PSTORE_TYPE_DMESG, PSTORE_TYPE_PPC_RTAS, PSTORE_TYPE_PPC_OF, PSTORE_TYPE_PPC_COMMON, -1 }; static int read_type; static unsigned long last_rtas_event; #endif static ssize_t pSeries_nvram_read(char *buf, size_t count, loff_t *index) { unsigned int i; unsigned long len; int done; unsigned long flags; char *p = buf; if (nvram_size == 0 || nvram_fetch == RTAS_UNKNOWN_SERVICE) return -ENODEV; if (*index >= nvram_size) return 0; i = *index; if (i + count > nvram_size) count = nvram_size - i; spin_lock_irqsave(&nvram_lock, flags); for (; count != 0; count -= len) { len = count; if (len > NVRW_CNT) len = NVRW_CNT; if ((rtas_call(nvram_fetch, 3, 2, &done, i, __pa(nvram_buf), len) != 0) || len != done) { spin_unlock_irqrestore(&nvram_lock, flags); return -EIO; } memcpy(p, nvram_buf, len); p += len; i += len; } spin_unlock_irqrestore(&nvram_lock, flags); *index = i; return p - buf; } static ssize_t pSeries_nvram_write(char *buf, size_t count, loff_t *index) { unsigned int i; unsigned long len; int done; unsigned long flags; const char *p = buf; if (nvram_size == 0 || nvram_store == RTAS_UNKNOWN_SERVICE) return -ENODEV; if (*index >= nvram_size) return 0; i = *index; if (i + count > nvram_size) count = nvram_size - i; spin_lock_irqsave(&nvram_lock, flags); for (; count != 0; count -= len) { len = count; if (len > NVRW_CNT) len = NVRW_CNT; memcpy(nvram_buf, p, len); if ((rtas_call(nvram_store, 3, 2, &done, i, __pa(nvram_buf), len) != 0) || len != done) { spin_unlock_irqrestore(&nvram_lock, flags); return -EIO; } p += len; i += len; } spin_unlock_irqrestore(&nvram_lock, flags); *index = i; return p - buf; } static ssize_t pSeries_nvram_get_size(void) { return nvram_size ? nvram_size : -ENODEV; } /* nvram_write_os_partition, nvram_write_error_log * * We need to buffer the error logs into nvram to ensure that we have * the failure information to decode. If we have a severe error there * is no way to guarantee that the OS or the machine is in a state to * get back to user land and write the error to disk. For example if * the SCSI device driver causes a Machine Check by writing to a bad * IO address, there is no way of guaranteeing that the device driver * is in any state that is would also be able to write the error data * captured to disk, thus we buffer it in NVRAM for analysis on the * next boot. * * In NVRAM the partition containing the error log buffer will looks like: * Header (in bytes): * +-----------+----------+--------+------------+------------------+ * | signature | checksum | length | name | data | * |0 |1 |2 3|4 15|16 length-1| * +-----------+----------+--------+------------+------------------+ * * The 'data' section would look like (in bytes): * +--------------+------------+-----------------------------------+ * | event_logged | sequence # | error log | * |0 3|4 7|8 error_log_size-1| * +--------------+------------+-----------------------------------+ * * event_logged: 0 if event has not been logged to syslog, 1 if it has * sequence #: The unique sequence # for each event. (until it wraps) * error log: The error log from event_scan */ int nvram_write_os_partition(struct nvram_os_partition *part, char * buff, int length, unsigned int err_type, unsigned int error_log_cnt) { int rc; loff_t tmp_index; struct err_log_info info; if (part->index == -1) { return -ESPIPE; } if (length > part->size) { length = part->size; } info.error_type = cpu_to_be32(err_type); info.seq_num = cpu_to_be32(error_log_cnt); tmp_index = part->index; rc = ppc_md.nvram_write((char *)&info, sizeof(struct err_log_info), &tmp_index); if (rc <= 0) { pr_err("%s: Failed nvram_write (%d)\n", __FUNCTION__, rc); return rc; } rc = ppc_md.nvram_write(buff, length, &tmp_index); if (rc <= 0) { pr_err("%s: Failed nvram_write (%d)\n", __FUNCTION__, rc); return rc; } return 0; } int nvram_write_error_log(char * buff, int length, unsigned int err_type, unsigned int error_log_cnt) { int rc = nvram_write_os_partition(&rtas_log_partition, buff, length, err_type, error_log_cnt); if (!rc) { last_unread_rtas_event = get_seconds(); #ifdef CONFIG_PSTORE last_rtas_event = get_seconds(); #endif } return rc; } /* nvram_read_partition * * Reads nvram partition for at most 'length' */ int nvram_read_partition(struct nvram_os_partition *part, char *buff, int length, unsigned int *err_type, unsigned int *error_log_cnt) { int rc; loff_t tmp_index; struct err_log_info info; if (part->index == -1) return -1; if (length > part->size) length = part->size; tmp_index = part->index; if (part->os_partition) { rc = ppc_md.nvram_read((char *)&info, sizeof(struct err_log_info), &tmp_index); if (rc <= 0) { pr_err("%s: Failed nvram_read (%d)\n", __FUNCTION__, rc); return rc; } } rc = ppc_md.nvram_read(buff, length, &tmp_index); if (rc <= 0) { pr_err("%s: Failed nvram_read (%d)\n", __FUNCTION__, rc); return rc; } if (part->os_partition) { *error_log_cnt = be32_to_cpu(info.seq_num); *err_type = be32_to_cpu(info.error_type); } return 0; } /* nvram_read_error_log * * Reads nvram for error log for at most 'length' */ int nvram_read_error_log(char *buff, int length, unsigned int *err_type, unsigned int *error_log_cnt) { return nvram_read_partition(&rtas_log_partition, buff, length, err_type, error_log_cnt); } /* This doesn't actually zero anything, but it sets the event_logged * word to tell that this event is safely in syslog. */ int nvram_clear_error_log(void) { loff_t tmp_index; int clear_word = ERR_FLAG_ALREADY_LOGGED; int rc; if (rtas_log_partition.index == -1) return -1; tmp_index = rtas_log_partition.index; rc = ppc_md.nvram_write((char *)&clear_word, sizeof(int), &tmp_index); if (rc <= 0) { printk(KERN_ERR "nvram_clear_error_log: Failed nvram_write (%d)\n", rc); return rc; } last_unread_rtas_event = 0; return 0; } /* pseries_nvram_init_os_partition * * This sets up a partition with an "OS" signature. * * The general strategy is the following: * 1.) If a partition with the indicated name already exists... * - If it's large enough, use it. * - Otherwise, recycle it and keep going. * 2.) Search for a free partition that is large enough. * 3.) If there's not a free partition large enough, recycle any obsolete * OS partitions and try again. * 4.) Will first try getting a chunk that will satisfy the requested size. * 5.) If a chunk of the requested size cannot be allocated, then try finding * a chunk that will satisfy the minum needed. * * Returns 0 on success, else -1. */ static int __init pseries_nvram_init_os_partition(struct nvram_os_partition *part) { loff_t p; int size; /* Look for ours */ p = nvram_find_partition(part->name, NVRAM_SIG_OS, &size); /* Found one but too small, remove it */ if (p && size < part->min_size) { pr_info("nvram: Found too small %s partition," " removing it...\n", part->name); nvram_remove_partition(part->name, NVRAM_SIG_OS, NULL); p = 0; } /* Create one if we didn't find */ if (!p) { p = nvram_create_partition(part->name, NVRAM_SIG_OS, part->req_size, part->min_size); if (p == -ENOSPC) { pr_info("nvram: No room to create %s partition, " "deleting any obsolete OS partitions...\n", part->name); nvram_remove_partition(NULL, NVRAM_SIG_OS, pseries_nvram_os_partitions); p = nvram_create_partition(part->name, NVRAM_SIG_OS, part->req_size, part->min_size); } } if (p <= 0) { pr_err("nvram: Failed to find or create %s" " partition, err %d\n", part->name, (int)p); return -1; } part->index = p; part->size = nvram_get_partition_size(p) - sizeof(struct err_log_info); return 0; } /* * Are we using the ibm,rtas-log for oops/panic reports? And if so, * would logging this oops/panic overwrite an RTAS event that rtas_errd * hasn't had a chance to read and process? Return 1 if so, else 0. * * We assume that if rtas_errd hasn't read the RTAS event in * NVRAM_RTAS_READ_TIMEOUT seconds, it's probably not going to. */ static int clobbering_unread_rtas_event(void) { return (oops_log_partition.index == rtas_log_partition.index && last_unread_rtas_event && get_seconds() - last_unread_rtas_event <= NVRAM_RTAS_READ_TIMEOUT); } /* Derived from logfs_compress() */ static int nvram_compress(const void *in, void *out, size_t inlen, size_t outlen) { int err, ret; ret = -EIO; err = zlib_deflateInit2(&stream, COMPR_LEVEL, Z_DEFLATED, WINDOW_BITS, MEM_LEVEL, Z_DEFAULT_STRATEGY); if (err != Z_OK) goto error; stream.next_in = in; stream.avail_in = inlen; stream.total_in = 0; stream.next_out = out; stream.avail_out = outlen; stream.total_out = 0; err = zlib_deflate(&stream, Z_FINISH); if (err != Z_STREAM_END) goto error; err = zlib_deflateEnd(&stream); if (err != Z_OK) goto error; if (stream.total_out >= stream.total_in) goto error; ret = stream.total_out; error: return ret; } /* Compress the text from big_oops_buf into oops_buf. */ static int zip_oops(size_t text_len) { struct oops_log_info *oops_hdr = (struct oops_log_info *)oops_buf; int zipped_len = nvram_compress(big_oops_buf, oops_data, text_len, oops_data_sz); if (zipped_len < 0) { pr_err("nvram: compression failed; returned %d\n", zipped_len); pr_err("nvram: logging uncompressed oops/panic report\n"); return -1; } oops_hdr->version = cpu_to_be16(OOPS_HDR_VERSION); oops_hdr->report_length = cpu_to_be16(zipped_len); oops_hdr->timestamp = cpu_to_be64(get_seconds()); return 0; } #ifdef CONFIG_PSTORE static int nvram_pstore_open(struct pstore_info *psi) { /* Reset the iterator to start reading partitions again */ read_type = -1; return 0; } /** * nvram_pstore_write - pstore write callback for nvram * @type: Type of message logged * @reason: reason behind dump (oops/panic) * @id: identifier to indicate the write performed * @part: pstore writes data to registered buffer in parts, * part number will indicate the same. * @count: Indicates oops count * @compressed: Flag to indicate the log is compressed * @size: number of bytes written to the registered buffer * @psi: registered pstore_info structure * * Called by pstore_dump() when an oops or panic report is logged in the * printk buffer. * Returns 0 on successful write. */ static int nvram_pstore_write(enum pstore_type_id type, enum kmsg_dump_reason reason, u64 *id, unsigned int part, int count, bool compressed, size_t size, struct pstore_info *psi) { int rc; unsigned int err_type = ERR_TYPE_KERNEL_PANIC; struct oops_log_info *oops_hdr = (struct oops_log_info *) oops_buf; /* part 1 has the recent messages from printk buffer */ if (part > 1 || type != PSTORE_TYPE_DMESG || clobbering_unread_rtas_event()) return -1; oops_hdr->version = cpu_to_be16(OOPS_HDR_VERSION); oops_hdr->report_length = cpu_to_be16(size); oops_hdr->timestamp = cpu_to_be64(get_seconds()); if (compressed) err_type = ERR_TYPE_KERNEL_PANIC_GZ; rc = nvram_write_os_partition(&oops_log_partition, oops_buf, (int) (sizeof(*oops_hdr) + size), err_type, count); if (rc != 0) return rc; *id = part; return 0; } /* * Reads the oops/panic report, rtas, of-config and common partition. * Returns the length of the data we read from each partition. * Returns 0 if we've been called before. */ static ssize_t nvram_pstore_read(u64 *id, enum pstore_type_id *type, int *count, struct timespec *time, char **buf, bool *compressed, struct pstore_info *psi) { struct oops_log_info *oops_hdr; unsigned int err_type, id_no, size = 0; struct nvram_os_partition *part = NULL; char *buff = NULL; int sig = 0; loff_t p; read_type++; switch (nvram_type_ids[read_type]) { case PSTORE_TYPE_DMESG: part = &oops_log_partition; *type = PSTORE_TYPE_DMESG; break; case PSTORE_TYPE_PPC_RTAS: part = &rtas_log_partition; *type = PSTORE_TYPE_PPC_RTAS; time->tv_sec = last_rtas_event; time->tv_nsec = 0; break; case PSTORE_TYPE_PPC_OF: sig = NVRAM_SIG_OF; part = &of_config_partition; *type = PSTORE_TYPE_PPC_OF; *id = PSTORE_TYPE_PPC_OF; time->tv_sec = 0; time->tv_nsec = 0; break; case PSTORE_TYPE_PPC_COMMON: sig = NVRAM_SIG_SYS; part = &common_partition; *type = PSTORE_TYPE_PPC_COMMON; *id = PSTORE_TYPE_PPC_COMMON; time->tv_sec = 0; time->tv_nsec = 0; break; default: return 0; } if (!part->os_partition) { p = nvram_find_partition(part->name, sig, &size); if (p <= 0) { pr_err("nvram: Failed to find partition %s, " "err %d\n", part->name, (int)p); return 0; } part->index = p; part->size = size; } buff = kmalloc(part->size, GFP_KERNEL); if (!buff) return -ENOMEM; if (nvram_read_partition(part, buff, part->size, &err_type, &id_no)) { kfree(buff); return 0; } *count = 0; if (part->os_partition) *id = id_no; if (nvram_type_ids[read_type] == PSTORE_TYPE_DMESG) { size_t length, hdr_size; oops_hdr = (struct oops_log_info *)buff; if (be16_to_cpu(oops_hdr->version) < OOPS_HDR_VERSION) { /* Old format oops header had 2-byte record size */ hdr_size = sizeof(u16); length = be16_to_cpu(oops_hdr->version); time->tv_sec = 0; time->tv_nsec = 0; } else { hdr_size = sizeof(*oops_hdr); length = be16_to_cpu(oops_hdr->report_length); time->tv_sec = be64_to_cpu(oops_hdr->timestamp); time->tv_nsec = 0; } *buf = kmalloc(length, GFP_KERNEL); if (*buf == NULL) return -ENOMEM; memcpy(*buf, buff + hdr_size, length); kfree(buff); if (err_type == ERR_TYPE_KERNEL_PANIC_GZ) *compressed = true; else *compressed = false; return length; } *buf = buff; return part->size; } static struct pstore_info nvram_pstore_info = { .owner = THIS_MODULE, .name = "nvram", .open = nvram_pstore_open, .read = nvram_pstore_read, .write = nvram_pstore_write, }; static int nvram_pstore_init(void) { int rc = 0; nvram_pstore_info.buf = oops_data; nvram_pstore_info.bufsize = oops_data_sz; rc = pstore_register(&nvram_pstore_info); if (rc != 0) pr_err("nvram: pstore_register() failed, defaults to " "kmsg_dump; returned %d\n", rc); return rc; } #else static int nvram_pstore_init(void) { return -1; } #endif static void __init nvram_init_oops_partition(int rtas_partition_exists) { int rc; rc = pseries_nvram_init_os_partition(&oops_log_partition); if (rc != 0) { if (!rtas_partition_exists) return; pr_notice("nvram: Using %s partition to log both" " RTAS errors and oops/panic reports\n", rtas_log_partition.name); memcpy(&oops_log_partition, &rtas_log_partition, sizeof(rtas_log_partition)); } oops_buf = kmalloc(oops_log_partition.size, GFP_KERNEL); if (!oops_buf) { pr_err("nvram: No memory for %s partition\n", oops_log_partition.name); return; } oops_data = oops_buf + sizeof(struct oops_log_info); oops_data_sz = oops_log_partition.size - sizeof(struct oops_log_info); rc = nvram_pstore_init(); if (!rc) return; /* * Figure compression (preceded by elimination of each line's * severity prefix) will reduce the oops/panic report to at most * 45% of its original size. */ big_oops_buf_sz = (oops_data_sz * 100) / 45; big_oops_buf = kmalloc(big_oops_buf_sz, GFP_KERNEL); if (big_oops_buf) { stream.workspace = kmalloc(zlib_deflate_workspacesize( WINDOW_BITS, MEM_LEVEL), GFP_KERNEL); if (!stream.workspace) { pr_err("nvram: No memory for compression workspace; " "skipping compression of %s partition data\n", oops_log_partition.name); kfree(big_oops_buf); big_oops_buf = NULL; } } else { pr_err("No memory for uncompressed %s data; " "skipping compression\n", oops_log_partition.name); stream.workspace = NULL; } rc = kmsg_dump_register(&nvram_kmsg_dumper); if (rc != 0) { pr_err("nvram: kmsg_dump_register() failed; returned %d\n", rc); kfree(oops_buf); kfree(big_oops_buf); kfree(stream.workspace); } } static int __init pseries_nvram_init_log_partitions(void) { int rc; /* Scan nvram for partitions */ nvram_scan_partitions(); rc = pseries_nvram_init_os_partition(&rtas_log_partition); nvram_init_oops_partition(rc == 0); return 0; } machine_arch_initcall(pseries, pseries_nvram_init_log_partitions); int __init pSeries_nvram_init(void) { struct device_node *nvram; const __be32 *nbytes_p; unsigned int proplen; nvram = of_find_node_by_type(NULL, "nvram"); if (nvram == NULL) return -ENODEV; nbytes_p = of_get_property(nvram, "#bytes", &proplen); if (nbytes_p == NULL || proplen != sizeof(unsigned int)) { of_node_put(nvram); return -EIO; } nvram_size = be32_to_cpup(nbytes_p); nvram_fetch = rtas_token("nvram-fetch"); nvram_store = rtas_token("nvram-store"); printk(KERN_INFO "PPC64 nvram contains %d bytes\n", nvram_size); of_node_put(nvram); ppc_md.nvram_read = pSeries_nvram_read; ppc_md.nvram_write = pSeries_nvram_write; ppc_md.nvram_size = pSeries_nvram_get_size; return 0; } /* * This is our kmsg_dump callback, called after an oops or panic report * has been written to the printk buffer. We want to capture as much * of the printk buffer as possible. First, capture as much as we can * that we think will compress sufficiently to fit in the lnx,oops-log * partition. If that's too much, go back and capture uncompressed text. */ static void oops_to_nvram(struct kmsg_dumper *dumper, enum kmsg_dump_reason reason) { struct oops_log_info *oops_hdr = (struct oops_log_info *)oops_buf; static unsigned int oops_count = 0; static bool panicking = false; static DEFINE_SPINLOCK(lock); unsigned long flags; size_t text_len; unsigned int err_type = ERR_TYPE_KERNEL_PANIC_GZ; int rc = -1; switch (reason) { case KMSG_DUMP_RESTART: case KMSG_DUMP_HALT: case KMSG_DUMP_POWEROFF: /* These are almost always orderly shutdowns. */ return; case KMSG_DUMP_OOPS: break; case KMSG_DUMP_PANIC: panicking = true; break; case KMSG_DUMP_EMERG: if (panicking) /* Panic report already captured. */ return; break; default: pr_err("%s: ignoring unrecognized KMSG_DUMP_* reason %d\n", __FUNCTION__, (int) reason); return; } if (clobbering_unread_rtas_event()) return; if (!spin_trylock_irqsave(&lock, flags)) return; if (big_oops_buf) { kmsg_dump_get_buffer(dumper, false, big_oops_buf, big_oops_buf_sz, &text_len); rc = zip_oops(text_len); } if (rc != 0) { kmsg_dump_rewind(dumper); kmsg_dump_get_buffer(dumper, false, oops_data, oops_data_sz, &text_len); err_type = ERR_TYPE_KERNEL_PANIC; oops_hdr->version = cpu_to_be16(OOPS_HDR_VERSION); oops_hdr->report_length = cpu_to_be16(text_len); oops_hdr->timestamp = cpu_to_be64(get_seconds()); } (void) nvram_write_os_partition(&oops_log_partition, oops_buf, (int) (sizeof(*oops_hdr) + text_len), err_type, ++oops_count); spin_unlock_irqrestore(&lock, flags); }