/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright(c) 2015 Intel Deutschland GmbH
*/
#ifndef __DEVCOREDUMP_H
#define __DEVCOREDUMP_H
#include <linux/device.h>
#include <linux/module.h>
#include <linux/vmalloc.h>
#include <linux/scatterlist.h>
#include <linux/slab.h>
/* if data isn't read by userspace after 5 minutes then delete it */
#define DEVCD_TIMEOUT (HZ * 60 * 5)
/*
* _devcd_free_sgtable - free all the memory of the given scatterlist table
* (i.e. both pages and scatterlist instances)
* NOTE: if two tables allocated and chained using the sg_chain function then
* this function should be called only once on the first table
* @table: pointer to sg_table to free
*/
static inline void _devcd_free_sgtable(struct scatterlist *table)
{
int i;
struct page *page;
struct scatterlist *iter;
struct scatterlist *delete_iter;
/* free pages */
iter = table;
for_each_sg(table, iter, sg_nents(table), i) {
page = sg_page(iter);
if (page)
__free_page(page);
}
/* then free all chained tables */
iter = table;
delete_iter = table; /* always points on a head of a table */
while (!sg_is_last(iter)) {
iter++;
if (sg_is_chain(iter)) {
iter = sg_chain_ptr(iter);
kfree(delete_iter);
delete_iter = iter;
}
}
/* free the last table */
kfree(delete_iter);
}
#ifdef CONFIG_DEV_COREDUMP
void dev_coredumpv(struct device *dev, void *data, size_t datalen,
gfp_t gfp);
void dev_coredumpm_timeout(struct device *dev, struct module *owner,
void *data, size_t datalen, gfp_t gfp,
ssize_t (*read)(char *buffer, loff_t offset,
size_t count, void *data,
size_t datalen),
void (*free)(void *data),
unsigned long timeout);
void dev_coredumpsg(struct device *dev, struct scatterlist *table,
size_t datalen, gfp_t gfp);
void dev_coredump_put(struct device *dev);
#else
static inline void dev_coredumpv(struct device *dev, void *data,
size_t datalen, gfp_t gfp)
{
vfree(data);
}
static inline void
dev_coredumpm_timeout(struct device *dev, struct module *owner,
void *data, size_t datalen, gfp_t gfp,
ssize_t (*read)(char *buffer, loff_t offset,
size_t count, void *data,
size_t datalen),
void (*free)(void *data),
unsigned long timeout)
{
free(data);
}
static inline void dev_coredumpsg(struct device *dev, struct scatterlist *table,
size_t datalen, gfp_t gfp)
{
_devcd_free_sgtable(table);
}
static inline void dev_coredump_put(struct device *dev)
{
}
#endif /* CONFIG_DEV_COREDUMP */
/**
* dev_coredumpm - create device coredump with read/free methods
* @dev: the struct device for the crashed device
* @owner: the module that contains the read/free functions, use %THIS_MODULE
* @data: data cookie for the @read/@free functions
* @datalen: length of the data
* @gfp: allocation flags
* @read: function to read from the given buffer
* @free: function to free the given buffer
*
* Creates a new device coredump for the given device. If a previous one hasn't
* been read yet, the new coredump is discarded. The data lifetime is determined
* by the device coredump framework and when it is no longer needed the @free
* function will be called to free the data.
*/
static inline void dev_coredumpm(struct device *dev, struct module *owner,
void *data, size_t datalen, gfp_t gfp,
ssize_t (*read)(char *buffer, loff_t offset, size_t count,
void *data, size_t datalen),
void (*free)(void *data))
{
dev_coredumpm_timeout(dev, owner, data, datalen, gfp, read, free,
DEVCD_TIMEOUT);
}
#endif /* __DEVCOREDUMP_H */