/*
* 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.
*
* /proc/powerpc/rtas/firmware_flash interface
*
* This file implements a firmware_flash interface to pump a firmware
* image into the kernel. At reboot time rtas_restart() will see the
* firmware image and flash it as it reboots (see rtas.c).
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/proc_fs.h>
#include <linux/reboot.h>
#include <asm/delay.h>
#include <asm/uaccess.h>
#include <asm/rtas.h>
#include <asm/abs_addr.h>
#define MODULE_VERS "1.0"
#define MODULE_NAME "rtas_flash"
#define FIRMWARE_FLASH_NAME "firmware_flash"
#define FIRMWARE_UPDATE_NAME "firmware_update"
#define MANAGE_FLASH_NAME "manage_flash"
#define VALIDATE_FLASH_NAME "validate_flash"
/* General RTAS Status Codes */
#define RTAS_RC_SUCCESS 0
#define RTAS_RC_HW_ERR -1
#define RTAS_RC_BUSY -2
/* Flash image status values */
#define FLASH_AUTH -9002 /* RTAS Not Service Authority Partition */
#define FLASH_NO_OP -1099 /* No operation initiated by user */
#define FLASH_IMG_SHORT -1005 /* Flash image shorter than expected */
#define FLASH_IMG_BAD_LEN -1004 /* Bad length value in flash list block */
#define FLASH_IMG_NULL_DATA -1003 /* Bad data value in flash list block */
#define FLASH_IMG_READY 0 /* Firmware img ready for flash on reboot */
/* Manage image status values */
#define MANAGE_AUTH -9002 /* RTAS Not Service Authority Partition */
#define MANAGE_ACTIVE_ERR -9001 /* RTAS Cannot Overwrite Active Img */
#define MANAGE_NO_OP -1099 /* No operation initiated by user */
#define MANAGE_PARAM_ERR -3 /* RTAS Parameter Error */
#define MANAGE_HW_ERR -1 /* RTAS Hardware Error */
/* Validate image status values */
#define VALIDATE_AUTH -9002 /* RTAS Not Service Authority Partition */
#define VALIDATE_NO_OP -1099 /* No operation initiated by the user */
#define VALIDATE_INCOMPLETE -1002 /* User copied < VALIDATE_BUF_SIZE */
#define VALIDATE_READY -1001 /* Firmware image ready for validation */
#define VALIDATE_PARAM_ERR -3 /* RTAS Parameter Error */
#define VALIDATE_HW_ERR -1 /* RTAS Hardware Error */
#define VALIDATE_TMP_UPDATE 0 /* Validate Return Status */
#define VALIDATE_FLASH_AUTH 1 /* Validate Return Status */
#define VALIDATE_INVALID_IMG 2 /* Validate Return Status */
#define VALIDATE_CUR_UNKNOWN 3 /* Validate Return Status */
#define VALIDATE_TMP_COMMIT_DL 4 /* Validate Return Status */
#define VALIDATE_TMP_COMMIT 5 /* Validate Return Status */
#define VALIDATE_TMP_UPDATE_DL 6 /* Validate Return Status */
/* ibm,manage-flash-image operation tokens */
#define RTAS_REJECT_TMP_IMG 0
#define RTAS_COMMIT_TMP_IMG 1
/* Array sizes */
#define VALIDATE_BUF_SIZE 4096
#define RTAS_MSG_MAXLEN 64
/* Quirk - RTAS requires 4k list length and block size */
#define RTAS_BLKLIST_LENGTH 4096
#define RTAS_BLK_SIZE 4096
struct flash_block {
char *data;
unsigned long length;
};
/* This struct is very similar but not identical to
* that needed by the rtas flash update.
* All we need to do for rtas is rewrite num_blocks
* into a version/length and translate the pointers
* to absolute.
*/
#define FLASH_BLOCKS_PER_NODE ((RTAS_BLKLIST_LENGTH - 16) / sizeof(struct flash_block))
struct flash_block_list {
unsigned long num_blocks;
struct flash_block_list *next;
struct flash_block blocks[FLASH_BLOCKS_PER_NODE];
};
static struct flash_block_list *rtas_firmware_flash_list;
/* Use slab cache to guarantee 4k alignment */
static struct kmem_cache *flash_block_cache = NULL;
#define FLASH_BLOCK_LIST_VERSION (1UL)
/* Local copy of the flash block list.
* We only allow one open of the flash proc file and create this
* list as we go. The rtas_firmware_flash_list varable will be
* set once the data is fully read.
*
* For convenience as we build the list we use virtual addrs,
* we do not fill in the version number, and the length field
* is treated as the number of entries currently in the block
* (i.e. not a byte count). This is all fixed when calling
* the flash routine.
*/
/* Status int must be first member of struct */
struct rtas_update_flash_t
{
int status; /* Flash update status */
struct flash_block_list *flist; /* Local copy of flash block list */
};
/* Status int must be first member of struct */
struct rtas_manage_flash_t
{
int status; /* Returned status */
unsigned int op; /* Reject or commit image */
};
/* Status int must be first member of struct */
struct rtas_validate_flash_t
{
int status; /* Returned status */
char buf[VALIDATE_BUF_SIZE]; /* Candidate image buffer */
unsigned int buf_size; /* Size of image buf */
unsigned int update_results; /* Update results token */
};
static DEFINE_SPINLOCK(flash_file_open_lock);
static struct proc_dir_entry *firmware_flash_pde;
static struct proc_dir_entry *firmware_update_pde;
static struct proc_dir_entry *validate_pde;
static struct proc_dir_entry *manage_pde;
/* Do simple sanity checks on the flash image. */
static int flash_list_valid(struct flash_block_list *flist)
{
struct flash_block_list *f;
int i;
unsigned long block_size, image_size;
/* Paranoid self test here. We also collect the image size. */
image_size = 0;
for (f = flist; f; f = f->next) {
for (i = 0; i < f->num_blocks; i++) {
if (f->blocks[i].data == NULL) {
return FLASH_IMG_NULL_DATA;
}
block_size = f->blocks[i].length;
if (block_size <= 0 || block_size > RTAS_BLK_SIZE) {
return FLASH_IMG_BAD_LEN;
}
image_size += block_size;
}
}
if (image_size < (256 << 10)) {
if (image_size < 2)
return FLASH_NO_OP;
}
printk(KERN_INFO "FLASH: flash image with %ld bytes stored for hardware flash on reboot\n", image_size);
return FLASH_IMG_READY;
}
static void free_flash_list(struct flash_block_list *f)
{
struct flash_block_list *next;
int i;
while (f) {
for (i = 0; i < f->num_blocks; i++)
kmem_cache_free(flash_block_cache, f->blocks[i].data);
next = f->next;
kmem_cache_free(flash_block_cache, f);
f = next;
}
}
static int rtas_flash_release(struct inode *inode, struct file *file)
{
struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
struct rtas_update_flash_t *uf;
uf = (struct rtas_update_flash_t *) dp->data;
if (uf->flist) {
/* File was opened in write mode for a new flash attempt */
/* Clear saved list */
if (rtas_firmware_flash_list) {
free_flash_list(rtas_firmware_flash_list);
rtas_firmware_flash_list = NULL;
}
if (uf->status != FLASH_AUTH)
uf->status = flash_list_valid(uf->flist);
if (uf->status == FLASH_IMG_READY)
rtas_firmware_flash_list = uf->flist;
else
free_flash_list(uf->flist);
uf->flist = NULL;
}
atomic_dec(&dp->count);
return 0;
}
static void get_flash_status_msg(int status, char *buf)
{
char *msg;
switch (status) {
case FLASH_AUTH:
msg = "error: this partition does not have service authority\n";
break;
case FLASH_NO_OP:
msg = "info: no firmware image for flash\n";
break;
case FLASH_IMG_SHORT:
msg = "error: flash image short\n";
break;
case FLASH_IMG_BAD_LEN:
msg = "error: internal error bad length\n";
break;
case FLASH_IMG_NULL_DATA:
msg = "error: internal error null data\n";
break;
case FLASH_IMG_READY:
msg = "ready: firmware image ready for flash on reboot\n";
break;
default:
sprintf(buf, "error: unexpected status value %d\n", status);
return;
}
strcpy(buf, msg);
}
/* Reading the proc file will show status (not the firmware contents) */
static ssize_t rtas_flash_read(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
struct rtas_update_flash_t *uf;
char msg[RTAS_MSG_MAXLEN];
uf = dp->data;
if (!strcmp(dp->name, FIRMWARE_FLASH_NAME)) {
get_flash_status_msg(uf->status, msg);
} else { /* FIRMWARE_UPDATE_NAME */
sprintf(msg, "%d\n", uf->status);
}
return simple_read_from_buffer(buf, count, ppos, msg, strlen(msg));
}
/* constructor for flash_block_cache */
void rtas_block_ctor(void *ptr)
{
memset(ptr, 0, RTAS_BLK_SIZE);
}
/* We could be much more efficient here. But to keep this function
* simple we allocate a page to the block list no matter how small the
* count is. If the system is low on memory it will be just as well
* that we fail....
*/
static ssize_t rtas_flash_write(struct file *file, const char __user *buffer,
size_t count, loff_t *off)
{
struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
struct rtas_update_flash_t *uf;
char *p;
int next_free;
struct flash_block_list *fl;
uf = (struct rtas_update_flash_t *) dp->data;
if (uf->status == FLASH_AUTH || count == 0)
return count; /* discard data */
/* In the case that the image is not ready for flashing, the memory
* allocated for the block list will be freed upon the release of the
* proc file
*/
if (uf->flist == NULL) {
uf->flist = kmem_cache_alloc(flash_block_cache, GFP_KERNEL);
if (!uf->flist)
return -ENOMEM;
}
fl = uf->flist;
while (fl->next)
fl = fl->next; /* seek to last block_list for append */
next_free = fl->num_blocks;
if (next_free == FLASH_BLOCKS_PER_NODE) {
/* Need to allocate another block_list */
fl->next = kmem_cache_alloc(flash_block_cache, GFP_KERNEL);
if (!fl->next)
return -ENOMEM;
fl = fl->next;
next_free = 0;
}
if (count > RTAS_BLK_SIZE)
count = RTAS_BLK_SIZE;
p = kmem_cache_alloc(flash_block_cache, GFP_KERNEL);
if (!p)
return -ENOMEM;
if(copy_from_user(p, buffer, count)) {
kmem_cache_free(flash_block_cache, p);
return -EFAULT;
}
fl->blocks[next_free].data = p;
fl->blocks[next_free].length = count;
fl->num_blocks++;
return count;
}
static int rtas_excl_open(struct inode *inode, struct file *file)
{
struct proc_dir_entry *dp = PDE(inode);
/* Enforce exclusive open with use count of PDE */
spin_lock(&flash_file_open_lock);
if (atomic_read(&dp->count) > 2) {
spin_unlock(&flash_file_open_lock);
return -EBUSY;
}
atomic_inc(&dp->count);
spin_unlock(&flash_file_open_lock);
return 0;
}
static int rtas_excl_release(struct inode *inode, struct file *file)
{
struct proc_dir_entry *dp = PDE(inode);
atomic_dec(&dp->count);
return 0;
}
static void manage_flash(struct rtas_manage_flash_t *args_buf)
{
s32 rc;
do {
rc = rtas_call(rtas_token("ibm,manage-flash-image"), 1,
1, NULL, args_buf->op);
} while (rtas_busy_delay(rc));
args_buf->status = rc;
}
static ssize_t manage_flash_read(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
struct rtas_manage_flash_t *args_buf;
char msg[RTAS_MSG_MAXLEN];
int msglen;
args_buf = dp->data;
if (args_buf == NULL)
return 0;
msglen = sprintf(msg, "%d\n", args_buf->status);
return simple_read_from_buffer(buf, count, ppos, msg, msglen);
}
static ssize_t manage_flash_write(struct file *file, const char __user *buf,
size_t count, loff_t *off)
{
struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
struct rtas_manage_flash_t *args_buf;
const char reject_str[] = "0";
const char commit_str[] = "1";
char stkbuf[10];
int op;
args_buf = (struct rtas_manage_flash_t *) dp->data;
if ((args_buf->status == MANAGE_AUTH) || (count == 0))
return count;
op = -1;
if (buf) {
if (count > 9) count = 9;
if (copy_from_user (stkbuf, buf, count)) {
return -EFAULT;
}
if (strncmp(stkbuf, reject_str, strlen(reject_str)) == 0)
op = RTAS_REJECT_TMP_IMG;
else if (strncmp(stkbuf, commit_str, strlen(commit_str)) == 0)
op = RTAS_COMMIT_TMP_IMG;
}
if (op == -1) /* buf is empty, or contains invalid string */
return -EINVAL;
args_buf->op = op;
manage_flash(args_buf);
return count;
}
static void validate_flash(struct rtas_validate_flash_t *args_buf)
{
int token = rtas_token("ibm,validate-flash-image");
int update_results;
s32 rc;
rc = 0;
do {
spin_lock(&rtas_data_buf_lock);
memcpy(rtas_data_buf, args_buf->buf, VALIDATE_BUF_SIZE);
rc = rtas_call(token, 2, 2, &update_results,
(u32) __pa(rtas_data_buf), args_buf->buf_size);
memcpy(args_buf->buf, rtas_data_buf, VALIDATE_BUF_SIZE);
spin_unlock(&rtas_data_buf_lock);
} while (rtas_busy_delay(rc));
args_buf->status = rc;
args_buf->update_results = update_results;
}
static int get_validate_flash_msg(struct rtas_validate_flash_t *args_buf,
char *msg)
{
int n;
if (args_buf->status >= VALIDATE_TMP_UPDATE) {
n = sprintf(msg, "%d\n", args_buf->update_results);
if ((args_buf->update_results >= VALIDATE_CUR_UNKNOWN) ||
(args_buf->update_results == VALIDATE_TMP_UPDATE))
n += sprintf(msg + n, "%s\n", args_buf->buf);
} else {
n = sprintf(msg, "%d\n", args_buf->status);
}
return n;
}
static ssize_t validate_flash_read(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
struct rtas_validate_flash_t *args_buf;
char msg[RTAS_MSG_MAXLEN];
int msglen;
args_buf = dp->data;
msglen = get_validate_flash_msg(args_buf, msg);
return simple_read_from_buffer(buf, count, ppos, msg, msglen);
}
static ssize_t validate_flash_write(struct file *file, const char __user *buf,
size_t count, loff_t *off)
{
struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
struct rtas_validate_flash_t *args_buf;
int rc;
args_buf = (struct rtas_validate_flash_t *) dp->data;
if (dp->data == NULL) {
dp->data = kmalloc(sizeof(struct rtas_validate_flash_t),
GFP_KERNEL);
if (dp->data == NULL)
return -ENOMEM;
}
/* We are only interested in the first 4K of the
* candidate image */
if ((*off >= VALIDATE_BUF_SIZE) ||
(args_buf->status == VALIDATE_AUTH)) {
*off += count;
return count;
}
if (*off + count >= VALIDATE_BUF_SIZE) {
count = VALIDATE_BUF_SIZE - *off;
args_buf->status = VALIDATE_READY;
} else {
args_buf->status = VALIDATE_INCOMPLETE;
}
if (!access_ok(VERIFY_READ, buf, count)) {
rc = -EFAULT;
goto done;
}
if (copy_from_user(args_buf->buf + *off, buf, count)) {
rc = -EFAULT;
goto done;
}
*off += count;
rc = count;
done:
if (rc < 0) {
kfree(dp->data);
dp->data = NULL;
}
return rc;
}
static int validate_flash_release(struct inode *inode, struct file *file)
{
struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
struct rtas_validate_flash_t *args_buf;
args_buf = (struct rtas_validate_flash_t *) dp->data;
if (args_buf->status == VALIDATE_READY) {
args_buf->buf_size = VALIDATE_BUF_SIZE;
validate_flash(args_buf);
}
/* The matching atomic_inc was in rtas_excl_open() */
atomic_dec(&dp->count);
return 0;
}
static void rtas_flash_firmware(int reboot_type)
{
unsigned long image_size;
struct flash_block_list *f, *next, *flist;
unsigned long rtas_block_list;
int i, status, update_token;
if (rtas_firmware_flash_list == NULL)
return; /* nothing to do */
if (reboot_type != SYS_RESTART) {
printk(KERN_ALERT "FLASH: firmware flash requires a reboot\n");
printk(KERN_ALERT "FLASH: the firmware image will NOT be flashed\n");
return;
}
update_token = rtas_token("ibm,update-flash-64-and-reboot");
if (update_token == RTAS_UNKNOWN_SERVICE) {
printk(KERN_ALERT "FLASH: ibm,update-flash-64-and-reboot "
"is not available -- not a service partition?\n");
printk(KERN_ALERT "FLASH: firmware will not be flashed\n");
return;
}
/*
* NOTE: the "first" block must be under 4GB, so we create
* an entry with no data blocks in the reserved buffer in
* the kernel data segment.
*/
spin_lock(&rtas_data_buf_lock);
flist = (struct flash_block_list *)&rtas_data_buf[0];
flist->num_blocks = 0;
flist->next = rtas_firmware_flash_list;
rtas_block_list = virt_to_abs(flist);
if (rtas_block_list >= 4UL*1024*1024*1024) {
printk(KERN_ALERT "FLASH: kernel bug...flash list header addr above 4GB\n");
spin_unlock(&rtas_data_buf_lock);
return;
}
printk(KERN_ALERT "FLASH: preparing saved firmware image for flash\n");
/* Update the block_list in place. */
rtas_firmware_flash_list = NULL; /* too hard to backout on error */
image_size = 0;
for (f = flist; f; f = next) {
/* Translate data addrs to absolute */
for (i = 0; i < f->num_blocks; i++) {
f->blocks[i].data = (char *)virt_to_abs(f->blocks[i].data);
image_size += f->blocks[i].length;
}
next = f->next;
/* Don't translate NULL pointer for last entry */
if (f->next)
f->next = (struct flash_block_list *)virt_to_abs(f->next);
else
f->next = NULL;
/* make num_blocks into the version/length field */
f->num_blocks = (FLASH_BLOCK_LIST_VERSION << 56) | ((f->num_blocks+1)*16);
}
printk(KERN_ALERT "FLASH: flash image is %ld bytes\n", image_size);
printk(KERN_ALERT "FLASH: performing flash and reboot\n");
rtas_progress("Flashing \n", 0x0);
rtas_progress("Please Wait... ", 0x0);
printk(KERN_ALERT "FLASH: this will take several minutes. Do not power off!\n");
status = rtas_call(update_token, 1, 1, NULL, rtas_block_list);
switch (status) { /* should only get "bad" status */
case 0:
printk(KERN_ALERT "FLASH: success\n");
break;
case -1:
printk(KERN_ALERT "FLASH: hardware error. Firmware may not be not flashed\n");
break;
case -3:
printk(KERN_ALERT "FLASH: image is corrupt or not correct for this platform. Firmware not flashed\n");
break;
case -4:
printk(KERN_ALERT "FLASH: flash failed when partially complete. System may not reboot\n");
break;
default:
printk(KERN_ALERT "FLASH: unknown flash return code %d\n", status);
break;
}
spin_unlock(&rtas_data_buf_lock);
}
static void remove_flash_pde(struct proc_dir_entry *dp)
{
if (dp) {
kfree(dp->data);
remove_proc_entry(dp->name, dp->parent);
}
}
static int initialize_flash_pde_data(const char *rtas_call_name,
size_t buf_size,
struct proc_dir_entry *dp)
{
int *status;
int token;
dp->data = kzalloc(buf_size, GFP_KERNEL);
if (dp->data == NULL) {
remove_flash_pde(dp);
return -ENOMEM;
}
/*
* This code assumes that the status int is the first member of the
* struct
*/
status = (int *) dp->data;
token = rtas_token(rtas_call_name);
if (token == RTAS_UNKNOWN_SERVICE)
*status = FLASH_AUTH;
else
*status = FLASH_NO_OP;
return 0;
}
static struct proc_dir_entry *create_flash_pde(const char *filename,
const struct file_operations *fops)
{
return proc_create(filename, S_IRUSR | S_IWUSR, NULL, fops);
}
static const struct file_operations rtas_flash_operations = {
.owner = THIS_MODULE,
.read = rtas_flash_read,
.write = rtas_flash_write,
.open = rtas_excl_open,
.release = rtas_flash_release,
.llseek = default_llseek,
};
static const struct file_operations manage_flash_operations = {
.owner = THIS_MODULE,
.read = manage_flash_read,
.write = manage_flash_write,
.open = rtas_excl_open,
.release = rtas_excl_release,
.llseek = default_llseek,
};
static const struct file_operations validate_flash_operations = {
.owner = THIS_MODULE,
.read = validate_flash_read,
.write = validate_flash_write,
.open = rtas_excl_open,
.release = validate_flash_release,
.llseek = default_llseek,
};
static int __init rtas_flash_init(void)
{
int rc;
if (rtas_token("ibm,update-flash-64-and-reboot") ==
RTAS_UNKNOWN_SERVICE) {
printk(KERN_ERR "rtas_flash: no firmware flash support\n");
return 1;
}
firmware_flash_pde = create_flash_pde("powerpc/rtas/"
FIRMWARE_FLASH_NAME,
&rtas_flash_operations);
if (firmware_flash_pde == NULL) {
rc = -ENOMEM;
goto cleanup;
}
rc = initialize_flash_pde_data("ibm,update-flash-64-and-reboot",
sizeof(struct rtas_update_flash_t),
firmware_flash_pde);
if (rc != 0)
goto cleanup;
firmware_update_pde = create_flash_pde("powerpc/rtas/"
FIRMWARE_UPDATE_NAME,
&rtas_flash_operations);
if (firmware_update_pde == NULL) {
rc = -ENOMEM;
goto cleanup;
}
rc = initialize_flash_pde_data("ibm,update-flash-64-and-reboot",
sizeof(struct rtas_update_flash_t),
firmware_update_pde);
if (rc != 0)
goto cleanup;
validate_pde = create_flash_pde("powerpc/rtas/" VALIDATE_FLASH_NAME,
&validate_flash_operations);
if (validate_pde == NULL) {
rc = -ENOMEM;
goto cleanup;
}
rc = initialize_flash_pde_data("ibm,validate-flash-image",
sizeof(struct rtas_validate_flash_t),
validate_pde);
if (rc != 0)
goto cleanup;
manage_pde = create_flash_pde("powerpc/rtas/" MANAGE_FLASH_NAME,
&manage_flash_operations);
if (manage_pde == NULL) {
rc = -ENOMEM;
goto cleanup;
}
rc = initialize_flash_pde_data("ibm,manage-flash-image",
sizeof(struct rtas_manage_flash_t),
manage_pde);
if (rc != 0)
goto cleanup;
rtas_flash_term_hook = rtas_flash_firmware;
flash_block_cache = kmem_cache_create("rtas_flash_cache",
RTAS_BLK_SIZE, RTAS_BLK_SIZE, 0,
rtas_block_ctor);
if (!flash_block_cache) {
printk(KERN_ERR "%s: failed to create block cache\n",
__func__);
rc = -ENOMEM;
goto cleanup;
}
return 0;
cleanup:
remove_flash_pde(firmware_flash_pde);
remove_flash_pde(firmware_update_pde);
remove_flash_pde(validate_pde);
remove_flash_pde(manage_pde);
return rc;
}
static void __exit rtas_flash_cleanup(void)
{
rtas_flash_term_hook = NULL;
if (flash_block_cache)
kmem_cache_destroy(flash_block_cache);
remove_flash_pde(firmware_flash_pde);
remove_flash_pde(firmware_update_pde);
remove_flash_pde(validate_pde);
remove_flash_pde(manage_pde);
}
module_init(rtas_flash_init);
module_exit(rtas_flash_cleanup);
MODULE_LICENSE("GPL");