Commit b5d38e9b authored by Anton Vorontsov's avatar Anton Vorontsov Committed by Greg Kroah-Hartman
Browse files

pstore/ram: Add console messages handling 



The console log size is configurable via ramoops.console_size
module option, and the log itself is available via
<pstore-mount>/console-ramoops file.

Signed-off-by: default avatarAnton Vorontsov <anton.vorontsov@linaro.org>
Acked-by: default avatarKees Cook <keescook@chromium.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 755d66b4

fs/pstore/ram.c

+86 −14
Original line number Diff line number Diff line
@@ -41,6 +41,10 @@ module_param(record_size, ulong, 0400); 
MODULE_PARM_DESC(record_size,

		"size of each dump done on oops/panic");



static ulong ramoops_console_size = MIN_MEM_SIZE;

module_param_named(console_size, ramoops_console_size, ulong, 0400);

MODULE_PARM_DESC(console_size, "size of kernel console log");



static ulong mem_address;

module_param(mem_address, ulong, 0400);

MODULE_PARM_DESC(mem_address,
@@ -63,14 +67,17 @@ MODULE_PARM_DESC(ramoops_ecc, 


struct ramoops_context {

	struct persistent_ram_zone **przs;

	struct persistent_ram_zone *cprz;

	phys_addr_t phys_addr;

	unsigned long size;

	size_t record_size;

	size_t console_size;

	int dump_oops;

	bool ecc;

	unsigned int max_dump_cnt;

	unsigned int dump_write_cnt;

	unsigned int dump_read_cnt;

	unsigned int console_read_cnt;

	struct pstore_info pstore;

};
@@ -82,6 +89,7 @@ static int ramoops_pstore_open(struct pstore_info *psi) 
	struct ramoops_context *cxt = psi->data;



	cxt->dump_read_cnt = 0;

	cxt->console_read_cnt = 0;

	return 0;

}
@@ -124,6 +132,9 @@ static ssize_t ramoops_pstore_read(u64 *id, enum pstore_type_id *type, 
	prz = ramoops_get_next_prz(cxt->przs, &cxt->dump_read_cnt,

				   cxt->max_dump_cnt, id, type,

				   PSTORE_TYPE_DMESG, 1);

	if (!prz)

		prz = ramoops_get_next_prz(&cxt->cprz, &cxt->console_read_cnt,

					   1, id, type, PSTORE_TYPE_CONSOLE, 0);

	if (!prz)

		return 0;
@@ -167,7 +178,13 @@ static int ramoops_pstore_write(enum pstore_type_id type, 
	struct persistent_ram_zone *prz = cxt->przs[cxt->dump_write_cnt];

	size_t hlen;



	/* Currently ramoops is designed to only store dmesg dumps. */

	if (type == PSTORE_TYPE_CONSOLE) {

		if (!cxt->cprz)

			return -ENOMEM;

		persistent_ram_write(cxt->cprz, cxt->pstore.buf, size);

		return 0;

	}



	if (type != PSTORE_TYPE_DMESG)

		return -EINVAL;
@@ -204,12 +221,23 @@ static int ramoops_pstore_erase(enum pstore_type_id type, u64 id, 
				struct pstore_info *psi)

{

	struct ramoops_context *cxt = psi->data;

	struct persistent_ram_zone *prz;



	switch (type) {

	case PSTORE_TYPE_DMESG:

		if (id >= cxt->max_dump_cnt)

			return -EINVAL;

		prz = cxt->przs[id];

		break;

	case PSTORE_TYPE_CONSOLE:

		prz = cxt->cprz;

		break;

	default:

		return -EINVAL;

	}



	persistent_ram_free_old(cxt->przs[id]);

	persistent_ram_zap(cxt->przs[id]);

	persistent_ram_free_old(prz);

	persistent_ram_zap(prz);



	return 0;

}
@@ -276,6 +304,32 @@ static int ramoops_init_przs(struct device *dev, struct ramoops_context *cxt, 
	return err;

}



static int ramoops_init_prz(struct device *dev, struct ramoops_context *cxt,

			    struct persistent_ram_zone **prz,

			    phys_addr_t *paddr, size_t sz)

{

	if (!sz)

		return 0;



	if (*paddr + sz > *paddr + cxt->size)

		return -ENOMEM;



	*prz = persistent_ram_new(*paddr, sz, cxt->ecc);

	if (IS_ERR(*prz)) {

		int err = PTR_ERR(*prz);



		dev_err(dev, "failed to request mem region (0x%zx@0x%llx): %d\n",

			sz, (unsigned long long)*paddr, err);

		return err;

	}



	persistent_ram_zap(*prz);



	*paddr += sz;



	return 0;

}



static int __init ramoops_probe(struct platform_device *pdev)

{

	struct device *dev = &pdev->dev;
@@ -291,34 +345,50 @@ static int __init ramoops_probe(struct platform_device *pdev) 
	if (cxt->max_dump_cnt)

		goto fail_out;



	if (!pdata->mem_size || !pdata->record_size) {

		pr_err("The memory size and the record size must be "

	if (!pdata->mem_size || (!pdata->record_size && !pdata->console_size)) {

		pr_err("The memory size and the record/console size must be "

			"non-zero\n");

		goto fail_out;

	}



	pdata->mem_size = rounddown_pow_of_two(pdata->mem_size);

	pdata->record_size = rounddown_pow_of_two(pdata->record_size);

	pdata->console_size = rounddown_pow_of_two(pdata->console_size);



	cxt->dump_read_cnt = 0;

	cxt->size = pdata->mem_size;

	cxt->phys_addr = pdata->mem_address;

	cxt->record_size = pdata->record_size;

	cxt->console_size = pdata->console_size;

	cxt->dump_oops = pdata->dump_oops;

	cxt->ecc = pdata->ecc;



	paddr = cxt->phys_addr;



	dump_mem_sz = cxt->size;

	dump_mem_sz = cxt->size - cxt->console_size;

	err = ramoops_init_przs(dev, cxt, &paddr, dump_mem_sz);

	if (err) {

	if (err)

		goto fail_out;



	err = ramoops_init_prz(dev, cxt, &cxt->cprz, &paddr, cxt->console_size);

	if (err)

		goto fail_init_cprz;



	if (!cxt->przs && !cxt->cprz) {

		pr_err("memory size too small, minimum is %lu\n",

			cxt->record_size);

		goto fail_count;

			cxt->console_size + cxt->record_size);

		goto fail_cnt;

	}



	cxt->pstore.data = cxt;

	/*

	 * Console can handle any buffer size, so prefer dumps buffer

	 * size since usually it is smaller.

	 */

	if (cxt->przs)

		cxt->pstore.bufsize = cxt->przs[0]->buffer_size;

	else

		cxt->pstore.bufsize = cxt->cprz->buffer_size;

	cxt->pstore.buf = kmalloc(cxt->pstore.bufsize, GFP_KERNEL);

	spin_lock_init(&cxt->pstore.buf_lock);

	if (!cxt->pstore.buf) {
@@ -341,9 +411,8 @@ static int __init ramoops_probe(struct platform_device *pdev) 
	record_size = pdata->record_size;

	dump_oops = pdata->dump_oops;



	pr_info("attached 0x%lx@0x%llx (%ux0x%zx), ecc: %s\n",

	pr_info("attached 0x%lx@0x%llx, ecc: %s\n",

		cxt->size, (unsigned long long)cxt->phys_addr,

		cxt->max_dump_cnt, cxt->record_size,

		ramoops_ecc ? "on" : "off");



	return 0;
@@ -353,7 +422,9 @@ static int __init ramoops_probe(struct platform_device *pdev) 
fail_clear:

	cxt->pstore.bufsize = 0;

	cxt->max_dump_cnt = 0;

fail_count:

fail_cnt:

	kfree(cxt->cprz);

fail_init_cprz:

	ramoops_free_przs(cxt);

fail_out:

	return err;
@@ -405,6 +476,7 @@ static int __init ramoops_init(void) 
		dummy_data->mem_size = mem_size;

		dummy_data->mem_address = mem_address;

		dummy_data->record_size = record_size;

		dummy_data->console_size = ramoops_console_size;

		dummy_data->dump_oops = dump_oops;

		dummy_data->ecc = ramoops_ecc;

		dummy = platform_create_bundle(&ramoops_driver, ramoops_probe,

include/linux/pstore_ram.h

+1 −0
Original line number Diff line number Diff line
@@ -93,6 +93,7 @@ struct ramoops_platform_data { 
	unsigned long	mem_size;

	unsigned long	mem_address;

	unsigned long	record_size;

	unsigned long	console_size;

	int		dump_oops;

	bool		ecc;

};