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-rw-r--r--fs/pstore/ram.c648
1 files changed, 648 insertions, 0 deletions
diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c
new file mode 100644
index 000000000..44a549bee
--- /dev/null
+++ b/fs/pstore/ram.c
@@ -0,0 +1,648 @@
+/*
+ * 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/version.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/compiler.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 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 ramoops_ftrace_size = MIN_MEM_SIZE;
+module_param_named(ftrace_size, ramoops_ftrace_size, ulong, 0400);
+MODULE_PARM_DESC(ftrace_size, "size of ftrace log");
+
+static ulong ramoops_pmsg_size = MIN_MEM_SIZE;
+module_param_named(pmsg_size, ramoops_pmsg_size, ulong, 0400);
+MODULE_PARM_DESC(pmsg_size, "size of user space message log");
+
+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 unsigned int mem_type;
+module_param(mem_type, uint, 0600);
+MODULE_PARM_DESC(mem_type,
+ "set to 1 to try to use unbuffered memory (default 0)");
+
+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,
+ "if non-zero, the option enables ECC support and specifies "
+ "ECC buffer size in bytes (1 is a special value, means 16 "
+ "bytes ECC)");
+
+struct ramoops_context {
+ struct persistent_ram_zone **przs;
+ struct persistent_ram_zone *cprz;
+ struct persistent_ram_zone *fprz;
+ struct persistent_ram_zone *mprz;
+ phys_addr_t phys_addr;
+ unsigned long size;
+ unsigned int memtype;
+ size_t record_size;
+ size_t console_size;
+ size_t ftrace_size;
+ size_t pmsg_size;
+ int dump_oops;
+ struct persistent_ram_ecc_info ecc_info;
+ unsigned int max_dump_cnt;
+ unsigned int dump_write_cnt;
+ /* _read_cnt need clear on ramoops_pstore_open */
+ unsigned int dump_read_cnt;
+ unsigned int console_read_cnt;
+ unsigned int ftrace_read_cnt;
+ unsigned int pmsg_read_cnt;
+ 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->dump_read_cnt = 0;
+ cxt->console_read_cnt = 0;
+ cxt->ftrace_read_cnt = 0;
+ cxt->pmsg_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 (!prz)
+ return NULL;
+
+ /* Update old/shadowed buffer. */
+ if (update)
+ persistent_ram_save_old(prz);
+
+ if (!persistent_ram_old_size(prz))
+ return NULL;
+
+ *typep = type;
+ *id = i;
+
+ return prz;
+}
+
+static int ramoops_read_kmsg_hdr(char *buffer, struct timespec *time,
+ bool *compressed)
+{
+ char data_type;
+ int header_length = 0;
+
+ if (sscanf(buffer, RAMOOPS_KERNMSG_HDR "%lu.%lu-%c\n%n", &time->tv_sec,
+ &time->tv_nsec, &data_type, &header_length) == 3) {
+ if (data_type == 'C')
+ *compressed = true;
+ else
+ *compressed = false;
+ } else if (sscanf(buffer, RAMOOPS_KERNMSG_HDR "%lu.%lu\n%n",
+ &time->tv_sec, &time->tv_nsec, &header_length) == 2) {
+ *compressed = false;
+ } else {
+ time->tv_sec = 0;
+ time->tv_nsec = 0;
+ *compressed = false;
+ }
+ return header_length;
+}
+
+static bool prz_ok(struct persistent_ram_zone *prz)
+{
+ return !!prz && !!(persistent_ram_old_size(prz) +
+ persistent_ram_ecc_string(prz, NULL, 0));
+}
+
+static ssize_t ramoops_pstore_read(u64 *id, enum pstore_type_id *type,
+ int *count, struct timespec *time,
+ char **buf, bool *compressed,
+ struct pstore_info *psi)
+{
+ ssize_t size;
+ ssize_t ecc_notice_size;
+ struct ramoops_context *cxt = psi->data;
+ struct persistent_ram_zone *prz;
+ int header_length;
+
+ prz = ramoops_get_next_prz(cxt->przs, &cxt->dump_read_cnt,
+ cxt->max_dump_cnt, id, type,
+ PSTORE_TYPE_DMESG, 1);
+ if (!prz_ok(prz))
+ prz = ramoops_get_next_prz(&cxt->cprz, &cxt->console_read_cnt,
+ 1, id, type, PSTORE_TYPE_CONSOLE, 0);
+ if (!prz_ok(prz))
+ prz = ramoops_get_next_prz(&cxt->fprz, &cxt->ftrace_read_cnt,
+ 1, id, type, PSTORE_TYPE_FTRACE, 0);
+ if (!prz_ok(prz))
+ prz = ramoops_get_next_prz(&cxt->mprz, &cxt->pmsg_read_cnt,
+ 1, id, type, PSTORE_TYPE_PMSG, 0);
+ if (!prz_ok(prz))
+ return 0;
+
+ if (!persistent_ram_old(prz))
+ return 0;
+
+ size = persistent_ram_old_size(prz);
+ header_length = ramoops_read_kmsg_hdr(persistent_ram_old(prz), time,
+ compressed);
+ size -= header_length;
+
+ /* ECC correction notice */
+ ecc_notice_size = persistent_ram_ecc_string(prz, NULL, 0);
+
+ *buf = kmalloc(size + ecc_notice_size + 1, GFP_KERNEL);
+ if (*buf == NULL)
+ return -ENOMEM;
+
+ memcpy(*buf, (char *)persistent_ram_old(prz) + header_length, size);
+ persistent_ram_ecc_string(prz, *buf + size, ecc_notice_size + 1);
+
+ return size + ecc_notice_size;
+}
+
+static size_t ramoops_write_kmsg_hdr(struct persistent_ram_zone *prz,
+ bool compressed)
+{
+ char *hdr;
+ struct timespec timestamp;
+ size_t len;
+
+ /* Report zeroed timestamp if called before timekeeping has resumed. */
+ if (__getnstimeofday(&timestamp)) {
+ timestamp.tv_sec = 0;
+ timestamp.tv_nsec = 0;
+ }
+ hdr = kasprintf(GFP_ATOMIC, RAMOOPS_KERNMSG_HDR "%lu.%lu-%c\n",
+ (long)timestamp.tv_sec, (long)(timestamp.tv_nsec / 1000),
+ compressed ? 'C' : 'D');
+ WARN_ON_ONCE(!hdr);
+ len = hdr ? strlen(hdr) : 0;
+ persistent_ram_write(prz, hdr, len);
+ kfree(hdr);
+
+ return len;
+}
+
+static int notrace ramoops_pstore_write_buf(enum pstore_type_id type,
+ enum kmsg_dump_reason reason,
+ u64 *id, unsigned int part,
+ const char *buf,
+ bool compressed, size_t size,
+ struct pstore_info *psi)
+{
+ struct ramoops_context *cxt = psi->data;
+ struct persistent_ram_zone *prz;
+ size_t hlen;
+
+ if (type == PSTORE_TYPE_CONSOLE) {
+ if (!cxt->cprz)
+ return -ENOMEM;
+ persistent_ram_write(cxt->cprz, buf, size);
+ return 0;
+ } else if (type == PSTORE_TYPE_FTRACE) {
+ if (!cxt->fprz)
+ return -ENOMEM;
+ persistent_ram_write(cxt->fprz, buf, size);
+ return 0;
+ } else if (type == PSTORE_TYPE_PMSG) {
+ if (!cxt->mprz)
+ return -ENOMEM;
+ persistent_ram_write(cxt->mprz, buf, size);
+ return 0;
+ }
+
+ 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;
+
+ if (!cxt->przs)
+ return -ENOSPC;
+
+ prz = cxt->przs[cxt->dump_write_cnt];
+
+ hlen = ramoops_write_kmsg_hdr(prz, compressed);
+ if (size + hlen > prz->buffer_size)
+ size = prz->buffer_size - hlen;
+ persistent_ram_write(prz, buf, size);
+
+ cxt->dump_write_cnt = (cxt->dump_write_cnt + 1) % cxt->max_dump_cnt;
+
+ return 0;
+}
+
+static int ramoops_pstore_erase(enum pstore_type_id type, u64 id, int count,
+ struct timespec time, 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;
+ case PSTORE_TYPE_FTRACE:
+ prz = cxt->fprz;
+ break;
+ case PSTORE_TYPE_PMSG:
+ prz = cxt->mprz;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ persistent_ram_free_old(prz);
+ persistent_ram_zap(prz);
+
+ return 0;
+}
+
+static struct ramoops_context oops_cxt = {
+ .pstore = {
+ .owner = THIS_MODULE,
+ .name = "ramoops",
+ .open = ramoops_pstore_open,
+ .read = ramoops_pstore_read,
+ .write_buf = ramoops_pstore_write_buf,
+ .erase = ramoops_pstore_erase,
+ },
+};
+
+static void ramoops_free_przs(struct ramoops_context *cxt)
+{
+ int i;
+
+ cxt->max_dump_cnt = 0;
+ 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;
+
+ if (*paddr + dump_mem_sz - cxt->phys_addr > cxt->size) {
+ dev_err(dev, "no room for dumps\n");
+ return -ENOMEM;
+ }
+
+ 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");
+ goto fail_prz;
+ }
+
+ for (i = 0; i < cxt->max_dump_cnt; i++) {
+ size_t sz = cxt->record_size;
+
+ cxt->przs[i] = persistent_ram_new(*paddr, sz, 0,
+ &cxt->ecc_info,
+ cxt->memtype);
+ 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, u32 sig)
+{
+ if (!sz)
+ return 0;
+
+ if (*paddr + sz - cxt->phys_addr > cxt->size) {
+ dev_err(dev, "no room for mem region (0x%zx@0x%llx) in (0x%lx@0x%llx)\n",
+ sz, (unsigned long long)*paddr,
+ cxt->size, (unsigned long long)cxt->phys_addr);
+ return -ENOMEM;
+ }
+
+ *prz = persistent_ram_new(*paddr, sz, sig, &cxt->ecc_info, cxt->memtype);
+ 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 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;
+
+ /* Only a single ramoops area allowed at a time, so fail extra
+ * probes.
+ */
+ if (cxt->max_dump_cnt)
+ goto fail_out;
+
+ if (!pdata->mem_size || (!pdata->record_size && !pdata->console_size &&
+ !pdata->ftrace_size && !pdata->pmsg_size)) {
+ pr_err("The memory size and the record/console size must be "
+ "non-zero\n");
+ goto fail_out;
+ }
+
+ if (pdata->record_size && !is_power_of_2(pdata->record_size))
+ pdata->record_size = rounddown_pow_of_two(pdata->record_size);
+ if (pdata->console_size && !is_power_of_2(pdata->console_size))
+ pdata->console_size = rounddown_pow_of_two(pdata->console_size);
+ if (pdata->ftrace_size && !is_power_of_2(pdata->ftrace_size))
+ pdata->ftrace_size = rounddown_pow_of_two(pdata->ftrace_size);
+ if (pdata->pmsg_size && !is_power_of_2(pdata->pmsg_size))
+ pdata->pmsg_size = rounddown_pow_of_two(pdata->pmsg_size);
+
+ cxt->size = pdata->mem_size;
+ cxt->phys_addr = pdata->mem_address;
+ cxt->memtype = pdata->mem_type;
+ cxt->record_size = pdata->record_size;
+ cxt->console_size = pdata->console_size;
+ cxt->ftrace_size = pdata->ftrace_size;
+ cxt->pmsg_size = pdata->pmsg_size;
+ cxt->dump_oops = pdata->dump_oops;
+ cxt->ecc_info = pdata->ecc_info;
+
+ paddr = cxt->phys_addr;
+
+ dump_mem_sz = cxt->size - cxt->console_size - cxt->ftrace_size
+ - cxt->pmsg_size;
+ err = ramoops_init_przs(dev, cxt, &paddr, dump_mem_sz);
+ if (err)
+ goto fail_out;
+
+ err = ramoops_init_prz(dev, cxt, &cxt->cprz, &paddr,
+ cxt->console_size, 0);
+ if (err)
+ goto fail_init_cprz;
+
+ err = ramoops_init_prz(dev, cxt, &cxt->fprz, &paddr, cxt->ftrace_size,
+ LINUX_VERSION_CODE);
+ if (err)
+ goto fail_init_fprz;
+
+ err = ramoops_init_prz(dev, cxt, &cxt->mprz, &paddr, cxt->pmsg_size, 0);
+ if (err)
+ goto fail_init_mprz;
+
+ cxt->pstore.data = cxt;
+ /*
+ * Console can handle any buffer size, so prefer LOG_LINE_MAX. If we
+ * have to handle dumps, we must have at least record_size buffer. And
+ * for ftrace, bufsize is irrelevant (if bufsize is 0, buf will be
+ * ZERO_SIZE_PTR).
+ */
+ if (cxt->console_size)
+ cxt->pstore.bufsize = 1024; /* LOG_LINE_MAX */
+ cxt->pstore.bufsize = max(cxt->record_size, cxt->pstore.bufsize);
+ 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");
+ err = -ENOMEM;
+ 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;
+ ramoops_console_size = pdata->console_size;
+ ramoops_pmsg_size = pdata->pmsg_size;
+ ramoops_ftrace_size = pdata->ftrace_size;
+
+ pr_info("attached 0x%lx@0x%llx, ecc: %d/%d\n",
+ cxt->size, (unsigned long long)cxt->phys_addr,
+ cxt->ecc_info.ecc_size, cxt->ecc_info.block_size);
+
+ return 0;
+
+fail_buf:
+ kfree(cxt->pstore.buf);
+fail_clear:
+ cxt->pstore.bufsize = 0;
+ kfree(cxt->mprz);
+fail_init_mprz:
+ kfree(cxt->fprz);
+fail_init_fprz:
+ kfree(cxt->cprz);
+fail_init_cprz:
+ ramoops_free_przs(cxt);
+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_dump_cnt = 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 = {
+ .probe = ramoops_probe,
+ .remove = __exit_p(ramoops_remove),
+ .driver = {
+ .name = "ramoops",
+ },
+};
+
+static void ramoops_register_dummy(void)
+{
+ 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;
+ }
+
+ dummy_data->mem_size = mem_size;
+ dummy_data->mem_address = mem_address;
+ dummy_data->mem_type = 0;
+ dummy_data->record_size = record_size;
+ dummy_data->console_size = ramoops_console_size;
+ dummy_data->ftrace_size = ramoops_ftrace_size;
+ dummy_data->pmsg_size = ramoops_pmsg_size;
+ dummy_data->dump_oops = dump_oops;
+ /*
+ * For backwards compatibility ramoops.ecc=1 means 16 bytes ECC
+ * (using 1 byte for ECC isn't much of use anyway).
+ */
+ dummy_data->ecc_info.ecc_size = ramoops_ecc == 1 ? 16 : 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);
+ platform_device_unregister(dummy);
+ kfree(dummy_data);
+}
+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 v1.2.3-54-g00ecf (git 2.45.2) at 2024-11-17 20:15:59 +0000