diff options
Diffstat (limited to 'arch/powerpc/platforms/pseries/nvram.c')
| -rw-r--r-- | arch/powerpc/platforms/pseries/nvram.c | 543 |
1 files changed, 464 insertions, 79 deletions
diff --git a/arch/powerpc/platforms/pseries/nvram.c b/arch/powerpc/platforms/pseries/nvram.c index 00cc3a09488..0cc240b7f69 100644 --- a/arch/powerpc/platforms/pseries/nvram.c +++ b/arch/powerpc/platforms/pseries/nvram.c @@ -18,6 +18,9 @@ #include <linux/spinlock.h> #include <linux/slab.h> #include <linux/kmsg_dump.h> +#include <linux/pstore.h> +#include <linux/ctype.h> +#include <linux/zlib.h> #include <asm/uaccess.h> #include <asm/nvram.h> #include <asm/rtas.h> @@ -27,14 +30,21 @@ /* 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 { - int error_type; - unsigned int seq_num; + __be32 error_type; + __be32 seq_num; }; struct nvram_os_partition { @@ -43,20 +53,23 @@ struct nvram_os_partition { 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 + .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 + .index = -1, + .os_partition = true }; static const char *pseries_nvram_os_partitions[] = { @@ -65,10 +78,14 @@ static const char *pseries_nvram_os_partitions[] = { 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, - const char *old_msgs, unsigned long old_len, - const char *new_msgs, unsigned long new_len); + enum kmsg_dump_reason reason); static struct kmsg_dumper nvram_kmsg_dumper = { .dump = oops_to_nvram @@ -78,8 +95,65 @@ static struct kmsg_dumper nvram_kmsg_dumper = { #define NVRAM_RTAS_READ_TIMEOUT 5 /* seconds */ static unsigned long last_unread_rtas_event; /* timestamp */ -/* We preallocate oops_buf during init to avoid kmalloc during oops/panic. */ -static char *oops_buf; +/* + * 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) { @@ -217,20 +291,20 @@ int nvram_write_os_partition(struct nvram_os_partition *part, char * buff, length = part->size; } - info.error_type = err_type; - info.seq_num = error_log_cnt; + 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); + pr_err("%s: Failed nvram_write (%d)\n", __func__, 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); + pr_err("%s: Failed nvram_write (%d)\n", __func__, rc); return rc; } @@ -242,48 +316,71 @@ int nvram_write_error_log(char * buff, int length, { int rc = nvram_write_os_partition(&rtas_log_partition, buff, length, err_type, error_log_cnt); - if (!rc) + if (!rc) { last_unread_rtas_event = get_seconds(); +#ifdef CONFIG_PSTORE + last_rtas_event = get_seconds(); +#endif + } + return rc; } -/* nvram_read_error_log +/* nvram_read_partition * - * Reads nvram for error log for at most 'length' + * Reads nvram partition for at most 'length' */ -int nvram_read_error_log(char * buff, int length, - unsigned int * err_type, unsigned int * error_log_cnt) +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 (rtas_log_partition.index == -1) + if (part->index == -1) return -1; - if (length > rtas_log_partition.size) - length = rtas_log_partition.size; + if (length > part->size) + length = part->size; - tmp_index = rtas_log_partition.index; + tmp_index = part->index; - rc = ppc_md.nvram_read((char *)&info, sizeof(struct err_log_info), &tmp_index); - if (rc <= 0) { - printk(KERN_ERR "nvram_read_error_log: Failed nvram_read (%d)\n", rc); - return rc; + 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", __func__, rc); + return rc; + } } rc = ppc_md.nvram_read(buff, length, &tmp_index); if (rc <= 0) { - printk(KERN_ERR "nvram_read_error_log: Failed nvram_read (%d)\n", rc); + pr_err("%s: Failed nvram_read (%d)\n", __func__, rc); return rc; } - *error_log_cnt = info.seq_num; - *err_type = info.error_type; + 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. */ @@ -331,9 +428,6 @@ static int __init pseries_nvram_init_os_partition(struct nvram_os_partition loff_t p; int size; - /* Scan nvram for partitions */ - nvram_scan_partitions(); - /* Look for ours */ p = nvram_find_partition(part->name, NVRAM_SIG_OS, &size); @@ -372,6 +466,267 @@ static int __init pseries_nvram_init_os_partition(struct nvram_os_partition 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; @@ -387,11 +742,48 @@ static void __init nvram_init_oops_partition(int rtas_partition_exists) 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 <n> + * 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); - return; + kfree(big_oops_buf); + kfree(stream.workspace); } } @@ -399,6 +791,9 @@ 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; @@ -408,7 +803,7 @@ machine_arch_initcall(pseries, pseries_nvram_init_log_partitions); int __init pSeries_nvram_init(void) { struct device_node *nvram; - const unsigned int *nbytes_p; + const __be32 *nbytes_p; unsigned int proplen; nvram = of_find_node_by_type(NULL, "nvram"); @@ -421,7 +816,7 @@ int __init pSeries_nvram_init(void) return -EIO; } - nvram_size = *nbytes_p; + nvram_size = be32_to_cpup(nbytes_p); nvram_fetch = rtas_token("nvram-fetch"); nvram_store = rtas_token("nvram-store"); @@ -435,53 +830,25 @@ int __init pSeries_nvram_init(void) return 0; } -/* - * Try to capture the last capture_len bytes of the printk buffer. Return - * the amount actually captured. - */ -static size_t capture_last_msgs(const char *old_msgs, size_t old_len, - const char *new_msgs, size_t new_len, - char *captured, size_t capture_len) -{ - if (new_len >= capture_len) { - memcpy(captured, new_msgs + (new_len - capture_len), - capture_len); - return capture_len; - } else { - /* Grab the end of old_msgs. */ - size_t old_tail_len = min(old_len, capture_len - new_len); - memcpy(captured, old_msgs + (old_len - old_tail_len), - old_tail_len); - memcpy(captured + old_tail_len, new_msgs, new_len); - return old_tail_len + new_len; - } -} /* - * 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. + * 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 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); -} - -/* our kmsg_dump callback */ static void oops_to_nvram(struct kmsg_dumper *dumper, - enum kmsg_dump_reason reason, - const char *old_msgs, unsigned long old_len, - const char *new_msgs, unsigned long new_len) + 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: @@ -490,7 +857,6 @@ static void oops_to_nvram(struct kmsg_dumper *dumper, /* These are almost always orderly shutdowns. */ return; case KMSG_DUMP_OOPS: - case KMSG_DUMP_KEXEC: break; case KMSG_DUMP_PANIC: panicking = true; @@ -502,15 +868,34 @@ static void oops_to_nvram(struct kmsg_dumper *dumper, break; default: pr_err("%s: ignoring unrecognized KMSG_DUMP_* reason %d\n", - __FUNCTION__, (int) reason); + __func__, (int) reason); return; } if (clobbering_unread_rtas_event()) return; - text_len = capture_last_msgs(old_msgs, old_len, new_msgs, new_len, - oops_buf, oops_log_partition.size); + 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) text_len, ERR_TYPE_KERNEL_PANIC, ++oops_count); + (int) (sizeof(*oops_hdr) + text_len), err_type, + ++oops_count); + + spin_unlock_irqrestore(&lock, flags); } |
