pstore/ram: Switch to persistent_ram routines

The patch switches pstore RAM backend to use persistent_ram routines,
one step closer to the ECC support.

Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Acked-by: Marco Stornelli <marco.stornelli@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 59 insertions, 47 deletions

diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c
index e443c9c6914f..62b13eda4691 100644
--- a/fs/pstore/ram.c
+++ b/fs/pstore/ram.c
@@ -57,7 +57,7 @@ MODULE_PARM_DESC(dump_oops,
                 "set to 1 to dump oopses, 0 to only dump panics (default 1)");
 
 struct ramoops_context {
-        void *virt_addr;
+        struct persistent_ram_zone **przs;
         phys_addr_t phys_addr;
         unsigned long size;
         size_t record_size;
@@ -85,39 +85,56 @@ static ssize_t ramoops_pstore_read(u64 *id, enum pstore_type_id *type,
                                    struct pstore_info *psi)
 {
         ssize_t size;
-        char *rambuf;
         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;
 
-        rambuf = cxt->virt_addr + (*id * cxt->record_size);
-        size = strnlen(rambuf, cxt->record_size);
+        size = persistent_ram_old_size(prz);
         *buf = kmalloc(size, GFP_KERNEL);
         if (*buf == NULL)
                 return -ENOMEM;
-        memcpy(*buf, rambuf, size);
+        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)
 {
-        char *buf;
-        size_t res;
-        struct timeval timestamp;
         struct ramoops_context *cxt = psi->data;
-        size_t available = cxt->record_size;
+        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)
@@ -142,22 +159,10 @@ static int ramoops_pstore_write(enum pstore_type_id type,
         if (part != 1)
                 return -ENOSPC;
 
-        buf = cxt->virt_addr + (cxt->count * cxt->record_size);
-
-        res = sprintf(buf, "%s", RAMOOPS_KERNMSG_HDR);
-        buf += res;
-        available -= res;
-
-        do_gettimeofday(&timestamp);
-        res = sprintf(buf, "%lu.%lu\n", (long)timestamp.tv_sec, (long)timestamp.tv_usec);
-        buf += res;
-        available -= res;
-
-        if (size > available)
-                size = available;
-
-        memcpy(buf, cxt->pstore.buf, size);
-        memset(buf + size, '\0', available - size);
+        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;
 
@@ -167,14 +172,12 @@ static int ramoops_pstore_write(enum pstore_type_id type,
 static int ramoops_pstore_erase(enum pstore_type_id type, u64 id,
                                 struct pstore_info *psi)
 {
-        char *buf;
         struct ramoops_context *cxt = psi->data;
 
         if (id >= cxt->max_count)
                 return -EINVAL;
 
-        buf = cxt->virt_addr + (id * cxt->record_size);
-        memset(buf, '\0', cxt->record_size);
+        persistent_ram_free_old(cxt->przs[id]);
 
         return 0;
 }
@@ -192,9 +195,11 @@ static struct ramoops_context oops_cxt = {
 
 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.
@@ -232,8 +237,28 @@ static int __init ramoops_probe(struct platform_device *pdev)
         cxt->record_size = pdata->record_size;
         cxt->dump_oops = pdata->dump_oops;
 
+        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, 0);
+                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->record_size;
+        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) {
@@ -241,23 +266,10 @@ static int __init ramoops_probe(struct platform_device *pdev)
                 goto fail_clear;
         }
 
-        if (!request_mem_region(cxt->phys_addr, cxt->size, "ramoops")) {
-                pr_err("request mem region (0x%lx@0x%llx) failed\n",
-                        cxt->size, (unsigned long long)cxt->phys_addr);
-                err = -EINVAL;
-                goto fail_buf;
-        }
-
-        cxt->virt_addr = ioremap(cxt->phys_addr,  cxt->size);
-        if (!cxt->virt_addr) {
-                pr_err("ioremap failed\n");
-                goto fail_mem_region;
-        }
-
         err = pstore_register(&cxt->pstore);
         if (err) {
                 pr_err("registering with pstore failed\n");
-                goto fail_iounmap;
+                goto fail_buf;
         }
 
         /*
@@ -275,15 +287,15 @@ static int __init ramoops_probe(struct platform_device *pdev)
 
         return 0;
 
-fail_iounmap:
-        iounmap(cxt->virt_addr);
-fail_mem_region:
-        release_mem_region(cxt->phys_addr, cxt->size);
 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;
 }