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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-17 00:20:36 +0200 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-17 00:20:36 +0200 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/ppc64/kernel/nvram.c | |
download | linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/ppc64/kernel/nvram.c')
-rw-r--r-- | arch/ppc64/kernel/nvram.c | 746 |
1 files changed, 746 insertions, 0 deletions
diff --git a/arch/ppc64/kernel/nvram.c b/arch/ppc64/kernel/nvram.c new file mode 100644 index 000000000000..b9069c2d1933 --- /dev/null +++ b/arch/ppc64/kernel/nvram.c @@ -0,0 +1,746 @@ +/* + * 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 <linux/module.h> + +#include <linux/types.h> +#include <linux/errno.h> +#include <linux/fs.h> +#include <linux/miscdevice.h> +#include <linux/fcntl.h> +#include <linux/nvram.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <asm/uaccess.h> +#include <asm/nvram.h> +#include <asm/rtas.h> +#include <asm/prom.h> +#include <asm/machdep.h> +#include <asm/systemcfg.h> + +#undef DEBUG_NVRAM + +static int nvram_scan_partitions(void); +static int nvram_setup_partition(void); +static int nvram_create_os_partition(void); +static int nvram_remove_os_partition(void); + +static struct nvram_partition * nvram_part; +static long nvram_error_log_index = -1; +static long nvram_error_log_size = 0; + +int no_logging = 1; /* Until we initialize everything, + * make sure we don't try logging + * anything */ + +extern volatile int error_log_cnt; + +struct err_log_info { + int error_type; + unsigned int seq_num; +}; + +static loff_t dev_nvram_llseek(struct file *file, loff_t offset, int origin) +{ + int size; + + if (ppc_md.nvram_size == NULL) + return -ENODEV; + size = ppc_md.nvram_size(); + + switch (origin) { + case 1: + offset += file->f_pos; + break; + case 2: + offset += size; + break; + } + if (offset < 0) + return -EINVAL; + file->f_pos = offset; + return file->f_pos; +} + + +static ssize_t dev_nvram_read(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ + ssize_t len; + char *tmp_buffer; + int size; + + if (ppc_md.nvram_size == NULL) + return -ENODEV; + size = ppc_md.nvram_size(); + + if (!access_ok(VERIFY_WRITE, buf, count)) + return -EFAULT; + if (*ppos >= size) + return 0; + if (count > size) + count = size; + + tmp_buffer = (char *) kmalloc(count, GFP_KERNEL); + if (!tmp_buffer) { + printk(KERN_ERR "dev_read_nvram: kmalloc failed\n"); + return -ENOMEM; + } + + len = ppc_md.nvram_read(tmp_buffer, count, ppos); + if ((long)len <= 0) { + kfree(tmp_buffer); + return len; + } + + if (copy_to_user(buf, tmp_buffer, len)) { + kfree(tmp_buffer); + return -EFAULT; + } + + kfree(tmp_buffer); + return len; + +} + +static ssize_t dev_nvram_write(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + ssize_t len; + char * tmp_buffer; + int size; + + if (ppc_md.nvram_size == NULL) + return -ENODEV; + size = ppc_md.nvram_size(); + + if (!access_ok(VERIFY_READ, buf, count)) + return -EFAULT; + if (*ppos >= size) + return 0; + if (count > size) + count = size; + + tmp_buffer = (char *) kmalloc(count, GFP_KERNEL); + if (!tmp_buffer) { + printk(KERN_ERR "dev_nvram_write: kmalloc failed\n"); + return -ENOMEM; + } + + if (copy_from_user(tmp_buffer, buf, count)) { + kfree(tmp_buffer); + return -EFAULT; + } + + len = ppc_md.nvram_write(tmp_buffer, count, ppos); + if ((long)len <= 0) { + kfree(tmp_buffer); + return len; + } + + kfree(tmp_buffer); + return len; +} + +static int dev_nvram_ioctl(struct inode *inode, 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 (systemcfg->platform != PLATFORM_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 */ + } + return -EINVAL; +} + +struct file_operations nvram_fops = { + .owner = THIS_MODULE, + .llseek = dev_nvram_llseek, + .read = dev_nvram_read, + .write = dev_nvram_write, + .ioctl = dev_nvram_ioctl, +}; + +static struct miscdevice nvram_dev = { + NVRAM_MINOR, + "nvram", + &nvram_fops +}; + + +#ifdef DEBUG_NVRAM +static void nvram_print_partitions(char * label) +{ + struct list_head * p; + struct nvram_partition * tmp_part; + + printk(KERN_WARNING "--------%s---------\n", label); + printk(KERN_WARNING "indx\t\tsig\tchks\tlen\tname\n"); + list_for_each(p, &nvram_part->partition) { + tmp_part = list_entry(p, struct nvram_partition, partition); + printk(KERN_WARNING "%d \t%02x\t%02x\t%d\t%s\n", + tmp_part->index, tmp_part->header.signature, + tmp_part->header.checksum, tmp_part->header.length, + tmp_part->header.name); + } +} +#endif + + +static int nvram_write_header(struct nvram_partition * part) +{ + loff_t tmp_index; + int rc; + + tmp_index = part->index; + rc = ppc_md.nvram_write((char *)&part->header, NVRAM_HEADER_LEN, &tmp_index); + + return rc; +} + + +static unsigned char 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; +} + + +/* + * Find an nvram partition, sig can be 0 for any + * partition or name can be NULL for any name, else + * tries to match both + */ +struct nvram_partition *nvram_find_partition(int sig, const char *name) +{ + struct nvram_partition * part; + struct list_head * p; + + list_for_each(p, &nvram_part->partition) { + part = list_entry(p, struct nvram_partition, partition); + + if (sig && part->header.signature != sig) + continue; + if (name && 0 != strncmp(name, part->header.name, 12)) + continue; + return part; + } + return NULL; +} +EXPORT_SYMBOL(nvram_find_partition); + + +static int nvram_remove_os_partition(void) +{ + struct list_head *i; + struct list_head *j; + struct nvram_partition * part; + struct nvram_partition * cur_part; + int rc; + + list_for_each(i, &nvram_part->partition) { + part = list_entry(i, struct nvram_partition, partition); + if (part->header.signature != NVRAM_SIG_OS) + continue; + + /* Make os partition a free partition */ + part->header.signature = NVRAM_SIG_FREE; + sprintf(part->header.name, "wwwwwwwwwwww"); + part->header.checksum = nvram_checksum(&part->header); + + /* Merge contiguous free partitions backwards */ + list_for_each_prev(j, &part->partition) { + cur_part = list_entry(j, struct nvram_partition, partition); + if (cur_part == nvram_part || cur_part->header.signature != NVRAM_SIG_FREE) { + break; + } + + part->header.length += cur_part->header.length; + part->header.checksum = nvram_checksum(&part->header); + part->index = cur_part->index; + + list_del(&cur_part->partition); + kfree(cur_part); + j = &part->partition; /* fixup our loop */ + } + + /* Merge contiguous free partitions forwards */ + list_for_each(j, &part->partition) { + cur_part = list_entry(j, struct nvram_partition, partition); + if (cur_part == nvram_part || cur_part->header.signature != NVRAM_SIG_FREE) { + break; + } + + part->header.length += cur_part->header.length; + part->header.checksum = nvram_checksum(&part->header); + + list_del(&cur_part->partition); + kfree(cur_part); + j = &part->partition; /* fixup our loop */ + } + + rc = nvram_write_header(part); + if (rc <= 0) { + printk(KERN_ERR "nvram_remove_os_partition: nvram_write failed (%d)\n", rc); + return rc; + } + + } + + return 0; +} + +/* nvram_create_os_partition + * + * Create a OS linux partition to buffer error logs. + * Will create a partition starting at the first free + * space found if space has enough room. + */ +static int nvram_create_os_partition(void) +{ + struct list_head * p; + struct nvram_partition * part; + struct nvram_partition * new_part = NULL; + struct nvram_partition * free_part = NULL; + int seq_init[2] = { 0, 0 }; + loff_t tmp_index; + long size = 0; + int rc; + + /* 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(p, &nvram_part->partition) { + part = list_entry(p, struct nvram_partition, partition); + if (part->header.signature != NVRAM_SIG_FREE) + continue; + + if (part->header.length >= NVRAM_MAX_REQ) { + size = NVRAM_MAX_REQ; + free_part = part; + break; + } + if (!size && part->header.length >= NVRAM_MIN_REQ) { + size = NVRAM_MIN_REQ; + free_part = part; + } + } + if (!size) { + return -ENOSPC; + } + + /* Create our OS partition */ + new_part = (struct nvram_partition *) + kmalloc(sizeof(struct nvram_partition), GFP_KERNEL); + if (!new_part) { + printk(KERN_ERR "nvram_create_os_partition: kmalloc failed\n"); + return -ENOMEM; + } + + new_part->index = free_part->index; + new_part->header.signature = NVRAM_SIG_OS; + new_part->header.length = size; + sprintf(new_part->header.name, "ppc64,linux"); + new_part->header.checksum = nvram_checksum(&new_part->header); + + rc = nvram_write_header(new_part); + if (rc <= 0) { + printk(KERN_ERR "nvram_create_os_partition: nvram_write_header \ + failed (%d)\n", rc); + return rc; + } + + /* make sure and initialize to zero the sequence number and the error + type logged */ + tmp_index = new_part->index + NVRAM_HEADER_LEN; + rc = ppc_md.nvram_write((char *)&seq_init, sizeof(seq_init), &tmp_index); + if (rc <= 0) { + printk(KERN_ERR "nvram_create_os_partition: nvram_write failed (%d)\n", rc); + return rc; + } + + nvram_error_log_index = new_part->index + NVRAM_HEADER_LEN; + nvram_error_log_size = ((part->header.length - 1) * + NVRAM_BLOCK_LEN) - sizeof(struct err_log_info); + + list_add_tail(&new_part->partition, &free_part->partition); + + if (free_part->header.length <= size) { + list_del(&free_part->partition); + kfree(free_part); + return 0; + } + + /* Adjust the partition we stole the space from */ + 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) { + printk(KERN_ERR "nvram_create_os_partition: nvram_write_header " + "failed (%d)\n", rc); + return rc; + } + + return 0; +} + + +/* nvram_setup_partition + * + * This will setup the partition we need for buffering the + * error logs and cleanup partitions if needed. + * + * The general strategy is the following: + * 1.) If there is ppc64,linux partition large enough then use it. + * 2.) If there is not a ppc64,linux partition large enough, search + * for a free partition that is large enough. + * 3.) If there is not a free partition large enough remove + * _all_ OS partitions and consolidate the space. + * 4.) Will first try getting a chunk that will satisfy the maximum + * error log size (NVRAM_MAX_REQ). + * 5.) If the max chunk cannot be allocated then try finding a chunk + * that will satisfy the minum needed (NVRAM_MIN_REQ). + */ +static int nvram_setup_partition(void) +{ + struct list_head * p; + struct nvram_partition * part; + int rc; + + /* For now, we don't do any of this on pmac, until I + * have figured out if it's worth killing some unused stuffs + * in our nvram, as Apple defined partitions use pretty much + * all of the space + */ + if (systemcfg->platform == PLATFORM_POWERMAC) + return -ENOSPC; + + /* see if we have an OS partition that meets our needs. + will try getting the max we need. If not we'll delete + partitions and try again. */ + list_for_each(p, &nvram_part->partition) { + part = list_entry(p, struct nvram_partition, partition); + if (part->header.signature != NVRAM_SIG_OS) + continue; + + if (strcmp(part->header.name, "ppc64,linux")) + continue; + + if (part->header.length >= NVRAM_MIN_REQ) { + /* found our partition */ + nvram_error_log_index = part->index + NVRAM_HEADER_LEN; + nvram_error_log_size = ((part->header.length - 1) * + NVRAM_BLOCK_LEN) - sizeof(struct err_log_info); + return 0; + } + } + + /* try creating a partition with the free space we have */ + rc = nvram_create_os_partition(); + if (!rc) { + return 0; + } + + /* need to free up some space */ + rc = nvram_remove_os_partition(); + if (rc) { + return rc; + } + + /* create a partition in this new space */ + rc = nvram_create_os_partition(); + if (rc) { + printk(KERN_ERR "nvram_create_os_partition: Could not find a " + "NVRAM partition large enough\n"); + return rc; + } + + return 0; +} + + +static int 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) + return -ENODEV; + total_size = ppc_md.nvram_size(); + + header = (char *) 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); + + 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 = (struct nvram_partition *) + 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_part->partition); + + cur_index += phead.length * NVRAM_BLOCK_LEN; + } + err = 0; + + out: + kfree(header); + return err; +} + +static int __init nvram_init(void) +{ + int error; + int rc; + + 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; + } + + /* initialize our anchor for the nvram partition list */ + nvram_part = (struct nvram_partition *) kmalloc(sizeof(struct nvram_partition), GFP_KERNEL); + if (!nvram_part) { + printk(KERN_ERR "nvram_init: Failed kmalloc\n"); + return -ENOMEM; + } + INIT_LIST_HEAD(&nvram_part->partition); + + /* Get all the NVRAM partitions */ + error = nvram_scan_partitions(); + if (error) { + printk(KERN_ERR "nvram_init: Failed nvram_scan_partitions\n"); + return error; + } + + if(nvram_setup_partition()) + printk(KERN_WARNING "nvram_init: Could not find nvram partition" + " for nvram buffered error logging.\n"); + +#ifdef DEBUG_NVRAM + nvram_print_partitions("NVRAM Partitions"); +#endif + + return rc; +} + +void __exit nvram_cleanup(void) +{ + misc_deregister( &nvram_dev ); +} + + +#ifdef CONFIG_PPC_PSERIES + +/* 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 nvram_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_error_log(char * buff, int length, unsigned int err_type) +{ + int rc; + loff_t tmp_index; + struct err_log_info info; + + if (no_logging) { + return -EPERM; + } + + if (nvram_error_log_index == -1) { + return -ESPIPE; + } + + if (length > nvram_error_log_size) { + length = nvram_error_log_size; + } + + info.error_type = err_type; + info.seq_num = error_log_cnt; + + tmp_index = nvram_error_log_index; + + rc = ppc_md.nvram_write((char *)&info, sizeof(struct err_log_info), &tmp_index); + if (rc <= 0) { + printk(KERN_ERR "nvram_write_error_log: Failed nvram_write (%d)\n", rc); + return rc; + } + + rc = ppc_md.nvram_write(buff, length, &tmp_index); + if (rc <= 0) { + printk(KERN_ERR "nvram_write_error_log: Failed nvram_write (%d)\n", rc); + return rc; + } + + 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) +{ + int rc; + loff_t tmp_index; + struct err_log_info info; + + if (nvram_error_log_index == -1) + return -1; + + if (length > nvram_error_log_size) + length = nvram_error_log_size; + + tmp_index = nvram_error_log_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; + } + + 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); + return rc; + } + + error_log_cnt = info.seq_num; + *err_type = info.error_type; + + return 0; +} + +/* 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; + + tmp_index = nvram_error_log_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; + } + + return 0; +} + +#endif /* CONFIG_PPC_PSERIES */ + +module_init(nvram_init); +module_exit(nvram_cleanup); +MODULE_LICENSE("GPL"); |