summaryrefslogtreecommitdiff
path: root/drivers/block
diff options
context:
space:
mode:
authorSergey Senozhatsky <sergey.senozhatsky@gmail.com>2014-04-07 15:38:20 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2014-04-07 16:36:02 -0700
commitfcfa8d95cacf5cbbe6dee6b8d229fe86142266e0 (patch)
treeac63d65c9d0c9d8831eec5f07b4c491b18559d0c /drivers/block
parentd61f98c70e8b0d324e8e83be2ed546d6295e63f3 (diff)
zram: return error-valued pointer from zcomp_create()
Instead of returning just NULL, return ERR_PTR from zcomp_create() if compressing backend creation has failed. ERR_PTR(-EINVAL) for unsupported compression algorithm request, ERR_PTR(-ENOMEM) for allocation (zcomp or compression stream) error. Perform IS_ERR() check of returned from zcomp_create() value in disksize_store() and set return code to PTR_ERR(). Change suggested by Jerome Marchand. [akpm@linux-foundation.org: clean up error recovery flow] Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reported-by: Jerome Marchand <jmarchan@redhat.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/block')
-rw-r--r--drivers/block/zram/zcomp.c14
-rw-r--r--drivers/block/zram/zram_drv.c19
2 files changed, 18 insertions, 15 deletions
diff --git a/drivers/block/zram/zcomp.c b/drivers/block/zram/zcomp.c
index d5919031ca8b..5647d8fe1dc1 100644
--- a/drivers/block/zram/zcomp.c
+++ b/drivers/block/zram/zcomp.c
@@ -9,6 +9,7 @@
#include <linux/kernel.h>
#include <linux/string.h>
+#include <linux/err.h>
#include <linux/slab.h>
#include <linux/wait.h>
#include <linux/sched.h>
@@ -319,9 +320,10 @@ void zcomp_destroy(struct zcomp *comp)
/*
* search available compressors for requested algorithm.
- * allocate new zcomp and initialize it. return NULL
- * if requested algorithm is not supported or in case
- * of init error
+ * allocate new zcomp and initialize it. return compressing
+ * backend pointer or ERR_PTR if things went bad. ERR_PTR(-EINVAL)
+ * if requested algorithm is not supported, ERR_PTR(-ENOMEM) in
+ * case of allocation error.
*/
struct zcomp *zcomp_create(const char *compress, int max_strm)
{
@@ -330,11 +332,11 @@ struct zcomp *zcomp_create(const char *compress, int max_strm)
backend = find_backend(compress);
if (!backend)
- return NULL;
+ return ERR_PTR(-EINVAL);
comp = kzalloc(sizeof(struct zcomp), GFP_KERNEL);
if (!comp)
- return NULL;
+ return ERR_PTR(-ENOMEM);
comp->backend = backend;
if (max_strm > 1)
@@ -343,7 +345,7 @@ struct zcomp *zcomp_create(const char *compress, int max_strm)
zcomp_strm_single_create(comp);
if (!comp->stream) {
kfree(comp);
- return NULL;
+ return ERR_PTR(-ENOMEM);
}
return comp;
}
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index e4d536b485e6..6b462d27e7d7 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -31,6 +31,7 @@
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/vmalloc.h>
+#include <linux/err.h>
#include "zram_drv.h"
@@ -583,7 +584,7 @@ static ssize_t disksize_store(struct device *dev,
struct zcomp *comp;
struct zram_meta *meta;
struct zram *zram = dev_to_zram(dev);
- int err = -EINVAL;
+ int err;
disksize = memparse(buf, NULL);
if (!disksize)
@@ -595,18 +596,18 @@ static ssize_t disksize_store(struct device *dev,
return -ENOMEM;
comp = zcomp_create(zram->compressor, zram->max_comp_streams);
- if (!comp) {
+ if (IS_ERR(comp)) {
pr_info("Cannot initialise %s compressing backend\n",
zram->compressor);
- goto out_cleanup;
+ err = PTR_ERR(comp);
+ goto out_free_meta;
}
down_write(&zram->init_lock);
if (init_done(zram)) {
- up_write(&zram->init_lock);
pr_info("Cannot change disksize for initialized device\n");
err = -EBUSY;
- goto out_cleanup;
+ goto out_destroy_comp;
}
zram->meta = meta;
@@ -614,12 +615,12 @@ static ssize_t disksize_store(struct device *dev,
zram->disksize = disksize;
set_capacity(zram->disk, zram->disksize >> SECTOR_SHIFT);
up_write(&zram->init_lock);
-
return len;
-out_cleanup:
- if (comp)
- zcomp_destroy(comp);
+out_destroy_comp:
+ up_write(&zram->init_lock);
+ zcomp_destroy(comp);
+out_free_meta:
zram_meta_free(meta);
return err;
}