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-rw-r--r--fs/pstore/ram.c383
1 files changed, 383 insertions, 0 deletions
diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c
new file mode 100644
index 00000000000..9123cce28c1
--- /dev/null
+++ b/fs/pstore/ram.c
@@ -0,0 +1,383 @@
+/*
+ * RAM Oops/Panic logger
+ *
+ * Copyright (C) 2010 Marco Stornelli <marco.stornelli@gmail.com>
+ * Copyright (C) 2011 Kees Cook <keescook@chromium.org>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/pstore.h>
+#include <linux/time.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/pstore_ram.h>
+
+#define RAMOOPS_KERNMSG_HDR "===="
+#define MIN_MEM_SIZE 4096UL
+
+static ulong record_size = MIN_MEM_SIZE;
+module_param(record_size, ulong, 0400);
+MODULE_PARM_DESC(record_size,
+ "size of each dump done on oops/panic");
+
+static ulong mem_address;
+module_param(mem_address, ulong, 0400);
+MODULE_PARM_DESC(mem_address,
+ "start of reserved RAM used to store oops/panic logs");
+
+static ulong mem_size;
+module_param(mem_size, ulong, 0400);
+MODULE_PARM_DESC(mem_size,
+ "size of reserved RAM used to store oops/panic logs");
+
+static int dump_oops = 1;
+module_param(dump_oops, int, 0600);
+MODULE_PARM_DESC(dump_oops,
+ "set to 1 to dump oopses, 0 to only dump panics (default 1)");
+
+static int ramoops_ecc;
+module_param_named(ecc, ramoops_ecc, int, 0600);
+MODULE_PARM_DESC(ramoops_ecc,
+ "set to 1 to enable ECC support");
+
+struct ramoops_context {
+ struct persistent_ram_zone **przs;
+ phys_addr_t phys_addr;
+ unsigned long size;
+ size_t record_size;
+ int dump_oops;
+ bool ecc;
+ unsigned int count;
+ unsigned int max_count;
+ unsigned int read_count;
+ struct pstore_info pstore;
+};
+
+static struct platform_device *dummy;
+static struct ramoops_platform_data *dummy_data;
+
+static int ramoops_pstore_open(struct pstore_info *psi)
+{
+ struct ramoops_context *cxt = psi->data;
+
+ cxt->read_count = 0;
+ return 0;
+}
+
+static ssize_t ramoops_pstore_read(u64 *id, enum pstore_type_id *type,
+ struct timespec *time,
+ char **buf,
+ struct pstore_info *psi)
+{
+ ssize_t size;
+ struct ramoops_context *cxt = psi->data;
+ struct persistent_ram_zone *prz;
+
+ if (cxt->read_count >= cxt->max_count)
+ return -EINVAL;
+
+ *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;
+
+ size = persistent_ram_old_size(prz);
+ *buf = kmalloc(size, GFP_KERNEL);
+ if (*buf == NULL)
+ return -ENOMEM;
+ memcpy(*buf, persistent_ram_old(prz), size);
+
+ return size;
+}
+
+static size_t ramoops_write_kmsg_hdr(struct persistent_ram_zone *prz)
+{
+ char *hdr;
+ struct timeval timestamp;
+ size_t len;
+
+ do_gettimeofday(&timestamp);
+ hdr = kasprintf(GFP_ATOMIC, RAMOOPS_KERNMSG_HDR "%lu.%lu\n",
+ (long)timestamp.tv_sec, (long)timestamp.tv_usec);
+ WARN_ON_ONCE(!hdr);
+ len = hdr ? strlen(hdr) : 0;
+ persistent_ram_write(prz, hdr, len);
+ kfree(hdr);
+
+ return len;
+}
+
+static int ramoops_pstore_write(enum pstore_type_id type,
+ enum kmsg_dump_reason reason,
+ u64 *id,
+ unsigned int part,
+ size_t size, struct pstore_info *psi)
+{
+ struct ramoops_context *cxt = psi->data;
+ struct persistent_ram_zone *prz = cxt->przs[cxt->count];
+ size_t hlen;
+
+ /* Currently ramoops is designed to only store dmesg dumps. */
+ if (type != PSTORE_TYPE_DMESG)
+ return -EINVAL;
+
+ /* Out of the various dmesg dump types, ramoops is currently designed
+ * to only store crash logs, rather than storing general kernel logs.
+ */
+ if (reason != KMSG_DUMP_OOPS &&
+ reason != KMSG_DUMP_PANIC)
+ return -EINVAL;
+
+ /* Skip Oopes when configured to do so. */
+ if (reason == KMSG_DUMP_OOPS && !cxt->dump_oops)
+ return -EINVAL;
+
+ /* Explicitly only take the first part of any new crash.
+ * If our buffer is larger than kmsg_bytes, this can never happen,
+ * and if our buffer is smaller than kmsg_bytes, we don't want the
+ * report split across multiple records.
+ */
+ if (part != 1)
+ return -ENOSPC;
+
+ hlen = ramoops_write_kmsg_hdr(prz);
+ if (size + hlen > prz->buffer_size)
+ size = prz->buffer_size - hlen;
+ persistent_ram_write(prz, cxt->pstore.buf, size);
+
+ cxt->count = (cxt->count + 1) % cxt->max_count;
+
+ return 0;
+}
+
+static int ramoops_pstore_erase(enum pstore_type_id type, u64 id,
+ struct pstore_info *psi)
+{
+ struct ramoops_context *cxt = psi->data;
+
+ if (id >= cxt->max_count)
+ return -EINVAL;
+
+ persistent_ram_free_old(cxt->przs[id]);
+
+ return 0;
+}
+
+static struct ramoops_context oops_cxt = {
+ .pstore = {
+ .owner = THIS_MODULE,
+ .name = "ramoops",
+ .open = ramoops_pstore_open,
+ .read = ramoops_pstore_read,
+ .write = ramoops_pstore_write,
+ .erase = ramoops_pstore_erase,
+ },
+};
+
+static int __init 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;
+ int err = -EINVAL;
+ int i;
+
+ /* Only a single ramoops area allowed at a time, so fail extra
+ * probes.
+ */
+ if (cxt->max_count)
+ goto fail_out;
+
+ if (!pdata->mem_size || !pdata->record_size) {
+ pr_err("The memory size and the record 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);
+
+ /* 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->size = pdata->mem_size;
+ cxt->phys_addr = pdata->mem_address;
+ cxt->record_size = pdata->record_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");
+ 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;
+
+ 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;
+ }
+ }
+
+ cxt->pstore.data = cxt;
+ cxt->pstore.bufsize = cxt->przs[0]->buffer_size;
+ cxt->pstore.buf = kmalloc(cxt->pstore.bufsize, GFP_KERNEL);
+ spin_lock_init(&cxt->pstore.buf_lock);
+ if (!cxt->pstore.buf) {
+ pr_err("cannot allocate pstore buffer\n");
+ goto fail_clear;
+ }
+
+ err = pstore_register(&cxt->pstore);
+ if (err) {
+ pr_err("registering with pstore failed\n");
+ goto fail_buf;
+ }
+
+ /*
+ * Update the module parameter variables as well so they are visible
+ * through /sys/module/ramoops/parameters/
+ */
+ mem_size = pdata->mem_size;
+ mem_address = pdata->mem_address;
+ record_size = pdata->record_size;
+ dump_oops = pdata->dump_oops;
+
+ pr_info("attached 0x%lx@0x%llx (%ux0x%zx), ecc: %s\n",
+ cxt->size, (unsigned long long)cxt->phys_addr,
+ cxt->max_count, cxt->record_size,
+ ramoops_ecc ? "on" : "off");
+
+ return 0;
+
+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);
+fail_out:
+ return err;
+}
+
+static int __exit ramoops_remove(struct platform_device *pdev)
+{
+#if 0
+ /* TODO(kees): We cannot unload ramoops since pstore doesn't support
+ * unregistering yet.
+ */
+ struct ramoops_context *cxt = &oops_cxt;
+
+ iounmap(cxt->virt_addr);
+ release_mem_region(cxt->phys_addr, cxt->size);
+ cxt->max_count = 0;
+
+ /* TODO(kees): When pstore supports unregistering, call it here. */
+ kfree(cxt->pstore.buf);
+ cxt->pstore.bufsize = 0;
+
+ return 0;
+#endif
+ return -EBUSY;
+}
+
+static struct platform_driver ramoops_driver = {
+ .remove = __exit_p(ramoops_remove),
+ .driver = {
+ .name = "ramoops",
+ .owner = THIS_MODULE,
+ },
+};
+
+static int __init ramoops_init(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;
+ }
+
+ return ret;
+}
+
+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");
+MODULE_AUTHOR("Marco Stornelli <marco.stornelli@gmail.com>");
+MODULE_DESCRIPTION("RAM Oops/Panic logger/driver");
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-28 15:40:16 +0000