1 files changed, 214 insertions, 93 deletions

diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c
index 453030f9c5bc..58b93fbd117e 100644
--- a/fs/pstore/ram.c
+++ b/fs/pstore/ram.c
@@ -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 count;
-	unsigned int max_count;
-	unsigned int read_count;
+	unsigned int max_dump_cnt;
+	unsigned int dump_write_cnt;
+	unsigned int dump_read_cnt;
+	unsigned int console_read_cnt;
 	struct pstore_info pstore;
 };
 
@@ -81,10 +88,38 @@ static int ramoops_pstore_open(struct pstore_info *psi)
 {
 	struct ramoops_context *cxt = psi->data;
 
-	cxt->read_count = 0;
+	cxt->dump_read_cnt = 0;
+	cxt->console_read_cnt = 0;
 	return 0;
 }
 
+static struct persistent_ram_zone *
+ramoops_get_next_prz(struct persistent_ram_zone *przs[], uint *c, uint max,
+		     u64 *id,
+		     enum pstore_type_id *typep, enum pstore_type_id type,
+		     bool update)
+{
+	struct persistent_ram_zone *prz;
+	int i = (*c)++;
+
+	if (i >= max)
+		return NULL;
+
+	prz = przs[i];
+
+	if (update) {
+		/* Update old/shadowed buffer. */
+		persistent_ram_save_old(prz);
+		if (!persistent_ram_old_size(prz))
+			return NULL;
+	}
+
+	*typep = type;
+	*id = i;
+
+	return prz;
+}
+
 static ssize_t ramoops_pstore_read(u64 *id, enum pstore_type_id *type,
 				   struct timespec *time,
 				   char **buf,
@@ -94,20 +129,19 @@ static ssize_t ramoops_pstore_read(u64 *id, enum pstore_type_id *type,
 	struct ramoops_context *cxt = psi->data;
 	struct persistent_ram_zone *prz;
 
-	if (cxt->read_count >= cxt->max_count)
-		return -EINVAL;
+	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;
 
-	*id = cxt->read_count++;
-	prz = cxt->przs[*id];
-
-	/* Only supports dmesg output so far. */
-	*type = PSTORE_TYPE_DMESG;
 	/* TODO(kees): Bogus time for the moment. */
 	time->tv_sec = 0;
 	time->tv_nsec = 0;
 
-	/* Update old/shadowed buffer. */
-	persistent_ram_save_old(prz);
 	size = persistent_ram_old_size(prz);
 	*buf = kmalloc(size, GFP_KERNEL);
 	if (*buf == NULL)
@@ -141,10 +175,16 @@ static int ramoops_pstore_write(enum pstore_type_id type,
 				size_t size, struct pstore_info *psi)
 {
 	struct ramoops_context *cxt = psi->data;
-	struct persistent_ram_zone *prz = cxt->przs[cxt->count];
+	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;
 
@@ -172,7 +212,7 @@ static int ramoops_pstore_write(enum pstore_type_id type,
 		size = prz->buffer_size - hlen;
 	persistent_ram_write(prz, cxt->pstore.buf, size);
 
-	cxt->count = (cxt->count + 1) % cxt->max_count;
+	cxt->dump_write_cnt = (cxt->dump_write_cnt + 1) % cxt->max_dump_cnt;
 
 	return 0;
 }
@@ -181,12 +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;
 
-	if (id >= cxt->max_count)
+	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;
 }
@@ -202,73 +253,142 @@ static struct ramoops_context oops_cxt = {
 	},
 };
 
-static int __init ramoops_probe(struct platform_device *pdev)
+static void ramoops_free_przs(struct ramoops_context *cxt)
+{
+	int i;
+
+	if (!cxt->przs)
+		return;
+
+	for (i = 0; !IS_ERR_OR_NULL(cxt->przs[i]); i++)
+		persistent_ram_free(cxt->przs[i]);
+	kfree(cxt->przs);
+}
+
+static int ramoops_init_przs(struct device *dev, struct ramoops_context *cxt,
+			      phys_addr_t *paddr, size_t dump_mem_sz)
+{
+	int err = -ENOMEM;
+	int i;
+
+	if (!cxt->record_size)
+		return 0;
+
+	cxt->max_dump_cnt = dump_mem_sz / cxt->record_size;
+	if (!cxt->max_dump_cnt)
+		return -ENOMEM;
+
+	cxt->przs = kzalloc(sizeof(*cxt->przs) * cxt->max_dump_cnt,
+			     GFP_KERNEL);
+	if (!cxt->przs) {
+		dev_err(dev, "failed to initialize a prz array for dumps\n");
+		return -ENOMEM;
+	}
+
+	for (i = 0; i < cxt->max_dump_cnt; i++) {
+		size_t sz = cxt->record_size;
+
+		cxt->przs[i] = persistent_ram_new(*paddr, sz, cxt->ecc);
+		if (IS_ERR(cxt->przs[i])) {
+			err = PTR_ERR(cxt->przs[i]);
+			dev_err(dev, "failed to request mem region (0x%zx@0x%llx): %d\n",
+				sz, (unsigned long long)*paddr, err);
+			goto fail_prz;
+		}
+		*paddr += sz;
+	}
+
+	return 0;
+fail_prz:
+	ramoops_free_przs(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 __devinit ramoops_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct ramoops_platform_data *pdata = pdev->dev.platform_data;
 	struct ramoops_context *cxt = &oops_cxt;
+	size_t dump_mem_sz;
+	phys_addr_t paddr;
 	int err = -EINVAL;
-	int i;
 
 	/* Only a single ramoops area allowed at a time, so fail extra
 	 * probes.
 	 */
-	if (cxt->max_count)
+	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);
 
-	/* Check for the minimum memory size */
-	if (pdata->mem_size < MIN_MEM_SIZE &&
-			pdata->record_size < MIN_MEM_SIZE) {
-		pr_err("memory size too small, minimum is %lu\n",
-			MIN_MEM_SIZE);
-		goto fail_out;
-	}
-
-	if (pdata->mem_size < pdata->record_size) {
-		pr_err("The memory size must be larger than the "
-			"records size\n");
-		goto fail_out;
-	}
-
-	cxt->max_count = pdata->mem_size / pdata->record_size;
-	cxt->count = 0;
+	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;
 
-	cxt->przs = kzalloc(sizeof(*cxt->przs) * cxt->max_count, GFP_KERNEL);
-	if (!cxt->przs) {
-		err = -ENOMEM;
-		dev_err(dev, "failed to initialize a prz array\n");
+	paddr = cxt->phys_addr;
+
+	dump_mem_sz = cxt->size - cxt->console_size;
+	err = ramoops_init_przs(dev, cxt, &paddr, dump_mem_sz);
+	if (err)
 		goto fail_out;
-	}
 
-	for (i = 0; i < cxt->max_count; i++) {
-		size_t sz = cxt->record_size;
-		phys_addr_t start = cxt->phys_addr + sz * i;
+	err = ramoops_init_prz(dev, cxt, &cxt->cprz, &paddr, cxt->console_size);
+	if (err)
+		goto fail_init_cprz;
 
-		cxt->przs[i] = persistent_ram_new(start, sz, cxt->ecc);
-		if (IS_ERR(cxt->przs[i])) {
-			err = PTR_ERR(cxt->przs[i]);
-			dev_err(dev, "failed to request mem region (0x%zx@0x%llx): %d\n",
-				sz, (unsigned long long)start, err);
-			goto fail_przs;
-		}
+	if (!cxt->przs && !cxt->cprz) {
+		pr_err("memory size too small, minimum is %lu\n",
+			cxt->console_size + cxt->record_size);
+		goto fail_cnt;
 	}
 
 	cxt->pstore.data = cxt;
-	cxt->pstore.bufsize = cxt->przs[0]->buffer_size;
+	/*
+	 * 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) {
@@ -291,9 +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_count, cxt->record_size,
 		ramoops_ecc ? "on" : "off");
 
 	return 0;
@@ -302,11 +421,11 @@ fail_buf:
 	kfree(cxt->pstore.buf);
 fail_clear:
 	cxt->pstore.bufsize = 0;
-	cxt->max_count = 0;
-fail_przs:
-	for (i = 0; cxt->przs[i]; i++)
-		persistent_ram_free(cxt->przs[i]);
-	kfree(cxt->przs);
+	cxt->max_dump_cnt = 0;
+fail_cnt:
+	kfree(cxt->cprz);
+fail_init_cprz:
+	ramoops_free_przs(cxt);
 fail_out:
 	return err;
 }
@@ -321,7 +440,7 @@ static int __exit ramoops_remove(struct platform_device *pdev)
 
 	iounmap(cxt->virt_addr);
 	release_mem_region(cxt->phys_addr, cxt->size);
-	cxt->max_count = 0;
+	cxt->max_dump_cnt = 0;
 
 	/* TODO(kees): When pstore supports unregistering, call it here. */
 	kfree(cxt->pstore.buf);
@@ -333,6 +452,7 @@ static int __exit ramoops_remove(struct platform_device *pdev)
 }
 
 static struct platform_driver ramoops_driver = {
+	.probe		= ramoops_probe,
 	.remove		= __exit_p(ramoops_remove),
 	.driver		= {
 		.name	= "ramoops",
@@ -340,45 +460,46 @@ static struct platform_driver ramoops_driver = {
 	},
 };
 
-static int __init ramoops_init(void)
+static void ramoops_register_dummy(void)
 {
-	int ret;
-	ret = platform_driver_probe(&ramoops_driver, ramoops_probe);
-	if (ret == -ENODEV) {
-		/*
-		 * If we didn't find a platform device, we use module parameters
-		 * building platform data on the fly.
-		 */
-		pr_info("platform device not found, using module parameters\n");
-		dummy_data = kzalloc(sizeof(struct ramoops_platform_data),
-				     GFP_KERNEL);
-		if (!dummy_data)
-			return -ENOMEM;
-		dummy_data->mem_size = mem_size;
-		dummy_data->mem_address = mem_address;
-		dummy_data->record_size = record_size;
-		dummy_data->dump_oops = dump_oops;
-		dummy_data->ecc = ramoops_ecc;
-		dummy = platform_create_bundle(&ramoops_driver, ramoops_probe,
-			NULL, 0, dummy_data,
-			sizeof(struct ramoops_platform_data));
-
-		if (IS_ERR(dummy))
-			ret = PTR_ERR(dummy);
-		else
-			ret = 0;
+	if (!mem_size)
+		return;
+
+	pr_info("using module parameters\n");
+
+	dummy_data = kzalloc(sizeof(*dummy_data), GFP_KERNEL);
+	if (!dummy_data) {
+		pr_info("could not allocate pdata\n");
+		return;
 	}
 
-	return ret;
+	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_device_register_data(NULL, "ramoops", -1,
+			dummy_data, sizeof(struct ramoops_platform_data));
+	if (IS_ERR(dummy)) {
+		pr_info("could not create platform device: %ld\n",
+			PTR_ERR(dummy));
+	}
 }
 
+static int __init ramoops_init(void)
+{
+	ramoops_register_dummy();
+	return platform_driver_register(&ramoops_driver);
+}
+postcore_initcall(ramoops_init);
+
 static void __exit ramoops_exit(void)
 {
 	platform_driver_unregister(&ramoops_driver);
 	kfree(dummy_data);
 }
-
-module_init(ramoops_init);
 module_exit(ramoops_exit);
 
 MODULE_LICENSE("GPL");