/* * 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 * * TODO: Split the /dev/nvram part (that one can use * drivers/char/generic_nvram.c) from the arch & partition * parsing code. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #undef DEBUG_NVRAM #define NVRAM_HEADER_LEN sizeof(struct nvram_header) #define NVRAM_BLOCK_LEN NVRAM_HEADER_LEN /* If change this size, then change the size of NVNAME_LEN */ struct nvram_header { unsigned char signature; unsigned char checksum; unsigned short length; /* Terminating null required only for names < 12 chars. */ char name[12]; }; struct nvram_partition { struct list_head partition; struct nvram_header header; unsigned int index; }; 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, ssize_t *ecc_notice_size, 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 = kmemdup(buff + hdr_size, length, GFP_KERNEL); kfree(buff); if (*buf == NULL) return -ENOMEM; *ecc_notice_size = 0; 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 && (rc != -EPERM)) /* Print error only when pstore.backend == nvram */ pr_err("nvram: pstore_register() failed, returned %d. " "Defaults to kmsg_dump\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 * 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) { if (ppc_md.nvram_size == NULL) return -ENODEV; return generic_file_llseek_size(file, offset, origin, MAX_LFS_FILESIZE, ppc_md.nvram_size()); } static ssize_t dev_nvram_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) { ssize_t ret; char *tmp = NULL; ssize_t size; if (!ppc_md.nvram_size) { ret = -ENODEV; goto out; } size = ppc_md.nvram_size(); if (size < 0) { ret = size; goto out; } if (*ppos >= size) { ret = 0; goto out; } count = min_t(size_t, count, size - *ppos); count = min(count, PAGE_SIZE); tmp = kmalloc(count, GFP_KERNEL); if (!tmp) { ret = -ENOMEM; goto out; } ret = ppc_md.nvram_read(tmp, count, ppos); if (ret <= 0) goto out; if (copy_to_user(buf, tmp, ret)) ret = -EFAULT; out: kfree(tmp); return ret; } static ssize_t dev_nvram_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) { ssize_t ret; char *tmp = NULL; ssize_t size; ret = -ENODEV; if (!ppc_md.nvram_size) goto out; ret = 0; size = ppc_md.nvram_size(); if (*ppos >= size || size < 0) goto out; count = min_t(size_t, count, size - *ppos); count = min(count, PAGE_SIZE); ret = -ENOMEM; tmp = kmalloc(count, GFP_KERNEL); if (!tmp) goto out; ret = -EFAULT; if (copy_from_user(tmp, buf, count)) goto out; ret = ppc_md.nvram_write(tmp, count, ppos); out: kfree(tmp); return ret; } static long dev_nvram_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { switch(cmd) { #ifdef CONFIG_PPC_PMAC case OBSOLETE_PMAC_NVRAM_GET_OFFSET: printk(KERN_WARNING "nvram: Using obsolete PMAC_NVRAM_GET_OFFSET ioctl\n"); case IOC_NVRAM_GET_OFFSET: { int part, offset; if (!machine_is(powermac)) return -EINVAL; if (copy_from_user(&part, (void __user*)arg, sizeof(part)) != 0) return -EFAULT; if (part < pmac_nvram_OF || part > pmac_nvram_NR) return -EINVAL; offset = pmac_get_partition(part); if (offset < 0) return offset; if (copy_to_user((void __user*)arg, &offset, sizeof(offset)) != 0) return -EFAULT; return 0; } #endif /* CONFIG_PPC_PMAC */ default: return -EINVAL; } } static const struct file_operations nvram_fops = { .owner = THIS_MODULE, .llseek = dev_nvram_llseek, .read = dev_nvram_read, .write = dev_nvram_write, .unlocked_ioctl = dev_nvram_ioctl, }; static struct miscdevice nvram_dev = { NVRAM_MINOR, "nvram", &nvram_fops }; #ifdef DEBUG_NVRAM static void __init nvram_print_partitions(char * label) { struct nvram_partition * tmp_part; printk(KERN_WARNING "--------%s---------\n", label); printk(KERN_WARNING "indx\t\tsig\tchks\tlen\tname\n"); list_for_each_entry(tmp_part, &nvram_partitions, partition) { printk(KERN_WARNING "%4d \t%02x\t%02x\t%d\t%12.12s\n", tmp_part->index, tmp_part->header.signature, tmp_part->header.checksum, tmp_part->header.length, tmp_part->header.name); } } #endif static int __init nvram_write_header(struct nvram_partition * part) { loff_t tmp_index; int rc; struct nvram_header phead; memcpy(&phead, &part->header, NVRAM_HEADER_LEN); phead.length = cpu_to_be16(phead.length); tmp_index = part->index; rc = ppc_md.nvram_write((char *)&phead, NVRAM_HEADER_LEN, &tmp_index); return rc; } static unsigned char __init nvram_checksum(struct nvram_header *p) { unsigned int c_sum, c_sum2; unsigned short *sp = (unsigned short *)p->name; /* assume 6 shorts */ c_sum = p->signature + p->length + sp[0] + sp[1] + sp[2] + sp[3] + sp[4] + sp[5]; /* The sum may have spilled into the 3rd byte. Fold it back. */ c_sum = ((c_sum & 0xffff) + (c_sum >> 16)) & 0xffff; /* The sum cannot exceed 2 bytes. Fold it into a checksum */ c_sum2 = (c_sum >> 8) + (c_sum << 8); c_sum = ((c_sum + c_sum2) >> 8) & 0xff; return c_sum; } /* * Per the criteria passed via nvram_remove_partition(), should this * partition be removed? 1=remove, 0=keep */ static int nvram_can_remove_partition(struct nvram_partition *part, const char *name, int sig, const char *exceptions[]) { if (part->header.signature != sig) return 0; if (name) { if (strncmp(name, part->header.name, 12)) return 0; } else if (exceptions) { const char **except; for (except = exceptions; *except; except++) { if (!strncmp(*except, part->header.name, 12)) return 0; } } return 1; } /** * nvram_remove_partition - Remove one or more partitions in nvram * @name: name of the partition to remove, or NULL for a * signature only match * @sig: signature of the partition(s) to remove * @exceptions: When removing all partitions with a matching signature, * leave these alone. */ int __init nvram_remove_partition(const char *name, int sig, const char *exceptions[]) { struct nvram_partition *part, *prev, *tmp; int rc; list_for_each_entry(part, &nvram_partitions, partition) { if (!nvram_can_remove_partition(part, name, sig, exceptions)) continue; /* Make partition a free partition */ part->header.signature = NVRAM_SIG_FREE; memset(part->header.name, 'w', 12); part->header.checksum = nvram_checksum(&part->header); rc = nvram_write_header(part); if (rc <= 0) { printk(KERN_ERR "nvram_remove_partition: nvram_write failed (%d)\n", rc); return rc; } } /* Merge contiguous ones */ prev = NULL; list_for_each_entry_safe(part, tmp, &nvram_partitions, partition) { if (part->header.signature != NVRAM_SIG_FREE) { prev = NULL; continue; } if (prev) { prev->header.length += part->header.length; prev->header.checksum = nvram_checksum(&prev->header); rc = nvram_write_header(prev); if (rc <= 0) { printk(KERN_ERR "nvram_remove_partition: nvram_write failed (%d)\n", rc); return rc; } list_del(&part->partition); kfree(part); } else prev = part; } return 0; } /** * nvram_create_partition - Create a partition in nvram * @name: name of the partition to create * @sig: signature of the partition to create * @req_size: size of data to allocate in bytes * @min_size: minimum acceptable size (0 means req_size) * * Returns a negative error code or a positive nvram index * of the beginning of the data area of the newly created * partition. If you provided a min_size smaller than req_size * you need to query for the actual size yourself after the * call using nvram_partition_get_size(). */ loff_t __init nvram_create_partition(const char *name, int sig, int req_size, int min_size) { struct nvram_partition *part; struct nvram_partition *new_part; struct nvram_partition *free_part = NULL; static char nv_init_vals[16]; loff_t tmp_index; long size = 0; int rc; /* Convert sizes from bytes to blocks */ req_size = _ALIGN_UP(req_size, NVRAM_BLOCK_LEN) / NVRAM_BLOCK_LEN; min_size = _ALIGN_UP(min_size, NVRAM_BLOCK_LEN) / NVRAM_BLOCK_LEN; /* If no minimum size specified, make it the same as the * requested size */ if (min_size == 0) min_size = req_size; if (min_size > req_size) return -EINVAL; /* Now add one block to each for the header */ req_size += 1; min_size += 1; /* Find a free partition that will give us the maximum needed size If can't find one that will give us the minimum size needed */ list_for_each_entry(part, &nvram_partitions, partition) { if (part->header.signature != NVRAM_SIG_FREE) continue; if (part->header.length >= req_size) { size = req_size; free_part = part; break; } if (part->header.length > size && part->header.length >= min_size) { size = part->header.length; free_part = part; } } if (!size) return -ENOSPC; /* Create our OS partition */ new_part = kmalloc(sizeof(*new_part), GFP_KERNEL); if (!new_part) { pr_err("%s: kmalloc failed\n", __func__); return -ENOMEM; } new_part->index = free_part->index; new_part->header.signature = sig; new_part->header.length = size; strncpy(new_part->header.name, name, 12); new_part->header.checksum = nvram_checksum(&new_part->header); rc = nvram_write_header(new_part); if (rc <= 0) { pr_err("%s: nvram_write_header failed (%d)\n", __func__, rc); kfree(new_part); return rc; } list_add_tail(&new_part->partition, &free_part->partition); /* Adjust or remove the partition we stole the space from */ if (free_part->header.length > size) { free_part->index += size * NVRAM_BLOCK_LEN; free_part->header.length -= size; free_part->header.checksum = nvram_checksum(&free_part->header); rc = nvram_write_header(free_part); if (rc <= 0) { pr_err("%s: nvram_write_header failed (%d)\n", __func__, rc); return rc; } } else { list_del(&free_part->partition); kfree(free_part); } /* Clear the new partition */ for (tmp_index = new_part->index + NVRAM_HEADER_LEN; tmp_index < ((size - 1) * NVRAM_BLOCK_LEN); tmp_index += NVRAM_BLOCK_LEN) { rc = ppc_md.nvram_write(nv_init_vals, NVRAM_BLOCK_LEN, &tmp_index); if (rc <= 0) { pr_err("%s: nvram_write failed (%d)\n", __func__, rc); return rc; } } return new_part->index + NVRAM_HEADER_LEN; } /** * nvram_get_partition_size - Get the data size of an nvram partition * @data_index: This is the offset of the start of the data of * the partition. The same value that is returned by * nvram_create_partition(). */ int nvram_get_partition_size(loff_t data_index) { struct nvram_partition *part; list_for_each_entry(part, &nvram_partitions, partition) { if (part->index + NVRAM_HEADER_LEN == data_index) return (part->header.length - 1) * NVRAM_BLOCK_LEN; } return -1; } /** * nvram_find_partition - Find an nvram partition by signature and name * @name: Name of the partition or NULL for any name * @sig: Signature to test against * @out_size: if non-NULL, returns the size of the data part of the partition */ loff_t nvram_find_partition(const char *name, int sig, int *out_size) { struct nvram_partition *p; list_for_each_entry(p, &nvram_partitions, partition) { if (p->header.signature == sig && (!name || !strncmp(p->header.name, name, 12))) { if (out_size) *out_size = (p->header.length - 1) * NVRAM_BLOCK_LEN; return p->index + NVRAM_HEADER_LEN; } } return 0; } int __init nvram_scan_partitions(void) { loff_t cur_index = 0; struct nvram_header phead; struct nvram_partition * tmp_part; unsigned char c_sum; char * header; int total_size; int err; if (ppc_md.nvram_size == NULL || ppc_md.nvram_size() <= 0) return -ENODEV; total_size = ppc_md.nvram_size(); header = kmalloc(NVRAM_HEADER_LEN, GFP_KERNEL); if (!header) { printk(KERN_ERR "nvram_scan_partitions: Failed kmalloc\n"); return -ENOMEM; } while (cur_index < total_size) { err = ppc_md.nvram_read(header, NVRAM_HEADER_LEN, &cur_index); if (err != NVRAM_HEADER_LEN) { printk(KERN_ERR "nvram_scan_partitions: Error parsing " "nvram partitions\n"); goto out; } cur_index -= NVRAM_HEADER_LEN; /* nvram_read will advance us */ memcpy(&phead, header, NVRAM_HEADER_LEN); phead.length = be16_to_cpu(phead.length); err = 0; c_sum = nvram_checksum(&phead); if (c_sum != phead.checksum) { printk(KERN_WARNING "WARNING: nvram partition checksum" " was %02x, should be %02x!\n", phead.checksum, c_sum); printk(KERN_WARNING "Terminating nvram partition scan\n"); goto out; } if (!phead.length) { printk(KERN_WARNING "WARNING: nvram corruption " "detected: 0-length partition\n"); goto out; } tmp_part = kmalloc(sizeof(struct nvram_partition), GFP_KERNEL); err = -ENOMEM; if (!tmp_part) { printk(KERN_ERR "nvram_scan_partitions: kmalloc failed\n"); goto out; } memcpy(&tmp_part->header, &phead, NVRAM_HEADER_LEN); tmp_part->index = cur_index; list_add_tail(&tmp_part->partition, &nvram_partitions); cur_index += phead.length * NVRAM_BLOCK_LEN; } err = 0; #ifdef DEBUG_NVRAM nvram_print_partitions("NVRAM Partitions"); #endif out: kfree(header); return err; } static int __init nvram_init(void) { int rc; BUILD_BUG_ON(NVRAM_BLOCK_LEN != 16); if (ppc_md.nvram_size == NULL || ppc_md.nvram_size() <= 0) return -ENODEV; rc = misc_register(&nvram_dev); if (rc != 0) { printk(KERN_ERR "nvram_init: failed to register device\n"); return rc; } return rc; } device_initcall(nvram_init);