pstore: fix one type of return value in pstore

the return type of function _read_ in pstore is size_t,
but in the callback function of _read_, the logic doesn't
consider it too much, which means if negative value (assuming
error here) is returned, it will be converted to positive because
of type casting. ssize_t is enough for this function.

Signed-off-by: Chen Gong <gong.chen@linux.intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

diff --git a/drivers/acpi/apei/erst.c b/drivers/acpi/apei/erst.c
index d6cb0ff6988e2797455e15e98426d021dd4fc005..d5a89d067f9882a80c50b2783f03e69b2f778f0a 100644 (file)
--- a/drivers/acpi/apei/erst.c
+++ b/drivers/acpi/apei/erst.c
@@ -929,7 +929,7 @@ static int erst_check_table(struct acpi_table_erst *erst_tab)
        return 0;
 }
 
-static size_t erst_reader(u64 *id, enum pstore_type_id *type,
+static ssize_t erst_reader(u64 *id, enum pstore_type_id *type,
                       struct timespec *time);
 static u64 erst_writer(enum pstore_type_id type, size_t size);
 
@@ -957,7 +957,7 @@ struct cper_pstore_record {
        char data[];
 } __packed;
 
-static size_t erst_reader(u64 *id, enum pstore_type_id *type,
+static ssize_t erst_reader(u64 *id, enum pstore_type_id *type,
                       struct timespec *time)
 {
        int rc;

diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c
index f835a25625ff5c7e74e5834cc9e6057697d02941..912403c2a93d65b028487fe2a2e04609b1aa5cfa 100644 (file)
--- a/fs/pstore/platform.c
+++ b/fs/pstore/platform.c
@@ -152,7 +152,7 @@ EXPORT_SYMBOL_GPL(pstore_register);
 void pstore_get_records(void)
 {
        struct pstore_info *psi = psinfo;
-       size_t                  size;
+       ssize_t                 size;
        u64                     id;
        enum pstore_type_id     type;
        struct timespec         time;
@@ -163,7 +163,7 @@ void pstore_get_records(void)
 
        mutex_lock(&psinfo->buf_mutex);
        while ((size = psi->read(&id, &type, &time)) > 0) {
-               if (pstore_mkfile(type, psi->name, id, psi->buf, size,
+               if (pstore_mkfile(type, psi->name, id, psi->buf, (size_t)size,
                                  time, psi->erase))
                        failed++;
        }

diff --git a/include/linux/pstore.h b/include/linux/pstore.h
index 41977737bb7d3bdf7b7d7be5d2ccf6dd4401ebd8..14ce2f5d08afa061a3cbcefec042acdf17d22f67 100644 (file)
--- a/include/linux/pstore.h
+++ b/include/linux/pstore.h
@@ -35,7 +35,7 @@ struct pstore_info {
        struct mutex    buf_mutex;      /* serialize access to 'buf' */
        char            *buf;
        size_t          bufsize;
-       size_t          (*read)(u64 *id, enum pstore_type_id *type,
+       ssize_t         (*read)(u64 *id, enum pstore_type_id *type,
                        struct timespec *time);
        u64             (*write)(enum pstore_type_id type, size_t size);
        int             (*erase)(u64 id);