From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933415Ab3GOQ5V (ORCPT ); Mon, 15 Jul 2013 12:57:21 -0400 Received: from e28smtp05.in.ibm.com ([122.248.162.5]:46366 "EHLO e28smtp05.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932297Ab3GOQ5T (ORCPT ); Mon, 15 Jul 2013 12:57:19 -0400 Subject: [PATCH 11/11] pstore/ram: Read and write to the 'compressed' flag of pstore To: linuxppc-dev@ozlabs.org, paulus@samba.org, linux-kernel@vger.kernel.org, benh@kernel.crashing.org From: Aruna Balakrishnaiah Cc: jkenisto@linux.vnet.ibm.com, tony.luck@intel.com, ananth@in.ibm.com, mahesh@linux.vnet.ibm.com, ccross@android.com, anton@samba.org, cbouatmailru@gmail.com, keescook@chromium.org Date: Mon, 15 Jul 2013 22:27:00 +0530 Message-ID: <20130715165700.1520.61365.stgit@aruna-ThinkPad-T420> In-Reply-To: <20130715164844.1520.27771.stgit@aruna-ThinkPad-T420> References: <20130715164844.1520.27771.stgit@aruna-ThinkPad-T420> User-Agent: StGit/0.16-41-gd1dd MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-TM-AS-MML: No X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13071516-8256-0000-0000-000008597428 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In pstore write, add character 'C'(compressed) or 'D'(decompressed) in the header while writing to Ram persistent buffer. In pstore read, read the header and update the 'compressed' flag accordingly. Signed-off-by: Aruna Balakrishnaiah --- fs/pstore/ram.c | 36 ++++++++++++++++++++++++++++-------- 1 file changed, 28 insertions(+), 8 deletions(-) diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c index 2927223..4027c20 100644 --- a/fs/pstore/ram.c +++ b/fs/pstore/ram.c @@ -131,6 +131,27 @@ ramoops_get_next_prz(struct persistent_ram_zone *przs[], uint *c, uint max, return prz; } +static void ramoops_read_kmsg_hdr(char *buffer, struct timespec *time, + bool *compressed) +{ + char data_type; + + if (sscanf(buffer, RAMOOPS_KERNMSG_HDR "%lu.%lu-%c\n", + &time->tv_sec, &time->tv_nsec, &data_type) == 3) { + if (data_type == 'C') + *compressed = true; + else + *compressed = false; + } else if (sscanf(buffer, RAMOOPS_KERNMSG_HDR "%lu.%lu\n", + &time->tv_sec, &time->tv_nsec) == 2) { + *compressed = false; + } else { + time->tv_sec = 0; + time->tv_nsec = 0; + *compressed = false; + } +} + static ssize_t ramoops_pstore_read(u64 *id, enum pstore_type_id *type, int *count, struct timespec *time, char **buf, bool *compressed, @@ -153,10 +174,6 @@ static ssize_t ramoops_pstore_read(u64 *id, enum pstore_type_id *type, if (!prz) return 0; - /* TODO(kees): Bogus time for the moment. */ - time->tv_sec = 0; - time->tv_nsec = 0; - size = persistent_ram_old_size(prz); /* ECC correction notice */ @@ -167,12 +184,14 @@ static ssize_t ramoops_pstore_read(u64 *id, enum pstore_type_id *type, return -ENOMEM; memcpy(*buf, persistent_ram_old(prz), size); + ramoops_read_kmsg_hdr(*buf, time, compressed); persistent_ram_ecc_string(prz, *buf + size, ecc_notice_size + 1); return size + ecc_notice_size; } -static size_t ramoops_write_kmsg_hdr(struct persistent_ram_zone *prz) +static size_t ramoops_write_kmsg_hdr(struct persistent_ram_zone *prz, + bool compressed) { char *hdr; struct timespec timestamp; @@ -183,8 +202,9 @@ static size_t ramoops_write_kmsg_hdr(struct persistent_ram_zone *prz) timestamp.tv_sec = 0; timestamp.tv_nsec = 0; } - hdr = kasprintf(GFP_ATOMIC, RAMOOPS_KERNMSG_HDR "%lu.%lu\n", - (long)timestamp.tv_sec, (long)(timestamp.tv_nsec / 1000)); + hdr = kasprintf(GFP_ATOMIC, RAMOOPS_KERNMSG_HDR "%lu.%lu-%c\n", + (long)timestamp.tv_sec, (long)(timestamp.tv_nsec / 1000), + compressed ? 'C' : 'D'); WARN_ON_ONCE(!hdr); len = hdr ? strlen(hdr) : 0; persistent_ram_write(prz, hdr, len); @@ -243,7 +263,7 @@ static int notrace ramoops_pstore_write_buf(enum pstore_type_id type, prz = cxt->przs[cxt->dump_write_cnt]; - hlen = ramoops_write_kmsg_hdr(prz); + hlen = ramoops_write_kmsg_hdr(prz, compressed); if (size + hlen > prz->buffer_size) size = prz->buffer_size - hlen; persistent_ram_write(prz, buf, size);