[PATCH 10/11] pstore/ram: Switch to persistent_ram routines

From: Anton Vorontsov
Date: Fri May 11 2012 - 20:20:17 EST

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@xxxxxxxxxx>
---
fs/pstore/ram.c | 109 ++++++++++++++++++++++++++++++-------------------------
1 file changed, 60 insertions(+), 49 deletions(-)

diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c
index b26b58e..cf0ad92 100644
--- a/fs/pstore/ram.c
+++ b/fs/pstore/ram.c
@@ -62,7 +62,7 @@ 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;
@@ -90,39 +90,56 @@ 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)
@@ -147,22 +164,10 @@ 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;

@@ -172,14 +177,12 @@ 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;
}
@@ -200,6 +203,7 @@ static int __init ramoops_probe(struct platform_device *pdev)
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.
@@ -237,32 +241,37 @@ 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) {
+ pr_err("failed to initialize a prz array\n");
+ goto fail_przs;
+ }
+
+ 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]);
+ pr_err("failed to initialize a prz\n");
+ goto fail_prz;
+ }
+ }
+
cxt->pstore.data = cxt;
- cxt->pstore.bufsize = cxt->record_size;
- cxt->pstore.buf = kmalloc(cxt->pstore.bufsize, GFP_KERNEL);
spin_lock_init(&cxt->pstore.buf_lock);
+ cxt->pstore.bufsize = cxt->przs[0]->buffer_size;
+ cxt->pstore.buf = kmalloc(cxt->pstore.bufsize, GFP_KERNEL);
if (!cxt->pstore.buf) {
pr_err("cannot allocate pstore buffer\n");
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_pstore;
}

/*
@@ -280,15 +289,17 @@ 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:
+fail_pstore:
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_prz:
+ kfree(cxt->pstore.buf);
fail_out:
return err;
}
--
1.7.9.2

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