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-rw-r--r--arch/powerpc/kernel/nvram_64.c677
1 files changed, 677 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/nvram_64.c b/arch/powerpc/kernel/nvram_64.c
index 34f7c9b7cd96..1e703f8ebad4 100644
--- a/arch/powerpc/kernel/nvram_64.c
+++ b/arch/powerpc/kernel/nvram_64.c
@@ -26,6 +26,9 @@
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
+#include <linux/kmsg_dump.h>
+#include <linux/pstore.h>
+#include <linux/zlib.h>
#include <asm/uaccess.h>
#include <asm/nvram.h>
#include <asm/rtas.h>
@@ -54,6 +57,680 @@ struct nvram_partition {
static LIST_HEAD(nvram_partitions);
+#ifdef CONFIG_PPC_PSERIES
+struct nvram_os_partition rtas_log_partition = {
+ .name = "ibm,rtas-log",
+ .req_size = 2079,
+ .min_size = 1055,
+ .index = -1,
+ .os_partition = true
+};
+#endif
+
+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 *nvram_os_partitions[] = {
+#ifdef CONFIG_PPC_PSERIES
+ "ibm,rtas-log",
+#endif
+ "lnx,oops-log",
+ NULL
+};
+
+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
+};
+
+/*
+ * 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
+#ifdef CONFIG_PPC_POWERNV
+static struct nvram_os_partition skiboot_partition = {
+ .name = "ibm,skiboot",
+ .index = -1,
+ .os_partition = false
+};
+#endif
+
+#ifdef CONFIG_PPC_PSERIES
+static struct nvram_os_partition of_config_partition = {
+ .name = "of-config",
+ .index = -1,
+ .os_partition = false
+};
+#endif
+
+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_COMMON,
+ -1,
+ -1,
+ -1
+};
+static int read_type;
+#endif
+
+/* nvram_write_os_partition
+ *
+ * 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", __func__, rc);
+ return rc;
+ }
+
+ rc = ppc_md.nvram_write(buff, length, &tmp_index);
+ if (rc <= 0) {
+ pr_err("%s: Failed nvram_write (%d)\n", __func__, rc);
+ return rc;
+ }
+
+ return 0;
+}
+
+/* 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", __func__, rc);
+ return rc;
+ }
+ }
+
+ rc = ppc_md.nvram_read(buff, length, &tmp_index);
+ if (rc <= 0) {
+ pr_err("%s: Failed nvram_read (%d)\n", __func__, 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_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.
+ */
+int __init 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,
+ 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;
+}
+
+/* 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(ktime_get_real_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))
+ return -1;
+
+ if (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(ktime_get_real_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_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;
+#ifdef CONFIG_PPC_PSERIES
+ 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;
+#endif
+#ifdef CONFIG_PPC_POWERNV
+ case PSTORE_TYPE_PPC_OPAL:
+ sig = NVRAM_SIG_FW;
+ part = &skiboot_partition;
+ *type = PSTORE_TYPE_PPC_OPAL;
+ *id = PSTORE_TYPE_PPC_OPAL;
+ time->tv_sec = 0;
+ time->tv_nsec = 0;
+ break;
+#endif
+ 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;
+
+ if (machine_is(pseries)) {
+ nvram_type_ids[2] = PSTORE_TYPE_PPC_RTAS;
+ nvram_type_ids[3] = PSTORE_TYPE_PPC_OF;
+ } else
+ nvram_type_ids[2] = PSTORE_TYPE_PPC_OPAL;
+
+ nvram_pstore_info.buf = oops_data;
+ nvram_pstore_info.bufsize = oops_data_sz;
+
+ spin_lock_init(&nvram_pstore_info.buf_lock);
+
+ 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
+
+void __init nvram_init_oops_partition(int rtas_partition_exists)
+{
+ int rc;
+
+ rc = nvram_init_os_partition(&oops_log_partition);
+ if (rc != 0) {
+#ifdef CONFIG_PPC_PSERIES
+ if (!rtas_partition_exists) {
+ pr_err("nvram: Failed to initialize oops partition!");
+ 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));
+#else
+ pr_err("nvram: Failed to initialize oops partition!");
+ return;
+#endif
+ }
+ 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);
+ kfree(big_oops_buf);
+ kfree(stream.workspace);
+ }
+}
+
+/*
+ * 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",
+ __func__, (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(ktime_get_real_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);
+}
+
static loff_t dev_nvram_llseek(struct file *file, loff_t offset, int origin)
{
int size;
generated by cgit v1.2.3-58-ga151 (git 2.39.0) at 2024-12-24 16:16:14 +0000