With compression initialization now separated from pstore_register(),
there is no longer a good reason to do compression method selection
during fs init. Instead, merge everything together into the late init.
Additionally cleans up the reporting to be more clear.
Signed-off-by: Kees Cook <keesc...@chromium.org>
---
This patch goes on top of Joel's. I'll have both in linux-next shortly...
---
fs/pstore/inode.c | 2 --
fs/pstore/internal.h | 3 --
fs/pstore/platform.c | 65 ++++++++++++++++++++++++++++----------------
3 files changed, 41 insertions(+), 29 deletions(-)
diff --git a/fs/pstore/inode.c b/fs/pstore/inode.c
index 5fcb845b9fec..d814723fb27d 100644
--- a/fs/pstore/inode.c
+++ b/fs/pstore/inode.c
@@ -486,8 +486,6 @@ static int __init init_pstore_fs(void)
{
int err;
- pstore_choose_compression();
-
/* Create a convenient mount point for people to access pstore */
err = sysfs_create_mount_point(fs_kobj, "pstore");
if (err)
diff --git a/fs/pstore/internal.h b/fs/pstore/internal.h
index fb767e28aeb2..c029314478fa 100644
--- a/fs/pstore/internal.h
+++ b/fs/pstore/internal.h
@@ -37,7 +37,4 @@ extern bool pstore_is_mounted(void);
extern void pstore_record_init(struct pstore_record *record,
struct pstore_info *psi);
-/* Called during module_init() */
-extern void __init pstore_choose_compression(void);
-
#endif
diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c
index f09066db2d4d..e4737a5fa68c 100644
--- a/fs/pstore/platform.c
+++ b/fs/pstore/platform.c
@@ -274,36 +274,56 @@ static int pstore_decompress(void *in, void *out,
static void allocate_buf_for_compression(void)
{
+ struct crypto_comp *ctx;
+ int size;
+ char *buf;
+
+ /* Skip if not built-in or compression backend not selected yet. */
if (!IS_ENABLED(CONFIG_PSTORE_COMPRESS) || !zbackend)
return;
+ /* Skip if no pstore backend yet or compression init already done. */
+ if (!psinfo || tfm)
+ return;
+
if (!crypto_has_comp(zbackend->name, 0, 0)) {
- pr_err("No %s compression\n", zbackend->name);
+ pr_err("Unknown compression: %s\n", zbackend->name);
return;
}
- big_oops_buf_sz = zbackend->zbufsize(psinfo->bufsize);
- if (big_oops_buf_sz <= 0)
+ size = zbackend->zbufsize(psinfo->bufsize);
+ if (size <= 0) {
+ pr_err("Invalid compression size for %s: %d\n",
+ zbackend->name, size);
return;
+ }
- big_oops_buf = kmalloc(big_oops_buf_sz, GFP_KERNEL);
- if (!big_oops_buf) {
- pr_err("allocate compression buffer error!\n");
+ buf = kmalloc(size, GFP_KERNEL);
+ if (!buf) {
+ pr_err("Failed %d byte compression buffer allocation for: %s\n",
+ size, zbackend->name);
return;
}
- tfm = crypto_alloc_comp(zbackend->name, 0, 0);
- if (IS_ERR_OR_NULL(tfm)) {
- kfree(big_oops_buf);
- big_oops_buf = NULL;
- pr_err("crypto_alloc_comp() failed!\n");
+ ctx = crypto_alloc_comp(zbackend->name, 0, 0);
+ if (IS_ERR_OR_NULL(ctx)) {
+ kfree(buf);
+ pr_err("crypto_alloc_comp('%s') failed: %ld\n", zbackend->name,
+ PTR_ERR(ctx));
return;
}
+
+ /* A non-NULL big_oops_buf indicates compression is available. */
+ tfm = ctx;
+ big_oops_buf_sz = size;
+ big_oops_buf = buf;
+
+ pr_info("Using compression: %s\n", zbackend->name);
}
static void free_buf_for_compression(void)
{
- if (IS_ENABLED(CONFIG_PSTORE_COMPRESS) && !IS_ERR_OR_NULL(tfm))
+ if (IS_ENABLED(CONFIG_PSTORE_COMPRESS) && tfm)
crypto_free_comp(tfm);
kfree(big_oops_buf);
big_oops_buf = NULL;
@@ -764,31 +784,28 @@ static void pstore_timefunc(struct timer_list *unused)
jiffies + msecs_to_jiffies(pstore_update_ms));
}
-void __init pstore_choose_compression(void)
+static int __init pstore_compression_late_init(void)
{
const struct pstore_zbackend *step;
if (!compress)
- return;
+ return 0;
+ /* Locate desired compression method. */
for (step = zbackends; step->name; step++) {
if (!strcmp(compress, step->name)) {
zbackend = step;
- pr_info("using %s compression\n", zbackend->name);
- return;
+ break;
}
}
-}
-static int __init pstore_compression_late_init(void)
-{
/*
- * Check if any pstore backends registered earlier but did not allocate
- * for compression because crypto was not ready, if so then initialize
- * compression.
+ * Check if any pstore backends registered earlier but did not
+ * initialize compression because crypto was not ready. If so,
+ * then initialize compression now.
*/
- if (psinfo && !tfm)
- allocate_buf_for_compression();
+ allocate_buf_for_compression();
+
return 0;
}
late_initcall(pstore_compression_late_init);
--
2.17.1
--
Kees Cook
Pixel Security
