Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755095Ab1EDDGc (ORCPT ); Tue, 3 May 2011 23:06:32 -0400 Received: from mga09.intel.com ([134.134.136.24]:13263 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752819Ab1EDDGb (ORCPT ); Tue, 3 May 2011 23:06:31 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.64,312,1301900400"; d="scan'208";a="637536891" From: Chen Gong To: tony.luck@intel.com, ying.huang@intel.com Cc: linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, Chen Gong Subject: [PATCH 2/3] fix pstore filesystem mount/remount issue Date: Wed, 4 May 2011 11:06:51 +0800 Message-Id: <1304478412-11843-3-git-send-email-gong.chen@linux.intel.com> X-Mailer: git-send-email 1.7.5.185.g0b9dee In-Reply-To: <1304478412-11843-1-git-send-email-gong.chen@linux.intel.com> References: <1304478412-11843-1-git-send-email-gong.chen@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4574 Lines: 162 Currently after mount/remount operation on pstore filesystem, the content on pstore will be lost. It is because current ERST implementation doesn't support multi-user usage, which moves internal pointer to the end after accessing it. Adding multi-user support for pstore usage. Signed-off-by: Chen Gong --- drivers/acpi/apei/erst.c | 48 +++++++++++++++++++++++++++++++++------------ fs/pstore/platform.c | 8 ++++++- include/linux/pstore.h | 2 + 3 files changed, 44 insertions(+), 14 deletions(-) diff --git a/drivers/acpi/apei/erst.c b/drivers/acpi/apei/erst.c index d5a89d0..ddb68c4 100644 --- a/drivers/acpi/apei/erst.c +++ b/drivers/acpi/apei/erst.c @@ -929,6 +929,8 @@ static int erst_check_table(struct acpi_table_erst *erst_tab) return 0; } +static int erst_open_pstore(struct pstore_info *psi); +static int erst_close_pstore(struct pstore_info *psi); 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); @@ -936,6 +938,8 @@ static u64 erst_writer(enum pstore_type_id type, size_t size); static struct pstore_info erst_info = { .owner = THIS_MODULE, .name = "erst", + .open = erst_open_pstore, + .close = erst_close_pstore, .read = erst_reader, .write = erst_writer, .erase = erst_clear @@ -957,12 +961,32 @@ struct cper_pstore_record { char data[]; } __packed; +static int reader_pos; + +static int erst_open_pstore(struct pstore_info *psi) +{ + int rc; + + if (erst_disable) + return -ENODEV; + + rc = erst_get_record_id_begin(&reader_pos); + + return rc; +} + +static int erst_close_pstore(struct pstore_info *psi) +{ + erst_get_record_id_end(); + + return 0; +} + static ssize_t erst_reader(u64 *id, enum pstore_type_id *type, struct timespec *time) { int rc; - ssize_t len; - unsigned long flags; + ssize_t len = 0; u64 record_id; struct cper_pstore_record *rcd = (struct cper_pstore_record *) (erst_info.buf - sizeof(*rcd)); @@ -970,24 +994,21 @@ static ssize_t erst_reader(u64 *id, enum pstore_type_id *type, if (erst_disable) return -ENODEV; - raw_spin_lock_irqsave(&erst_lock, flags); skip: - rc = __erst_get_next_record_id(&record_id); - if (rc) { - raw_spin_unlock_irqrestore(&erst_lock, flags); - return rc; - } + rc = erst_get_record_id_next(&reader_pos, &record_id); + if (rc) + goto out; + /* no more record */ if (record_id == APEI_ERST_INVALID_RECORD_ID) { - raw_spin_unlock_irqrestore(&erst_lock, flags); - return 0; + rc = -1; + goto out; } - len = __erst_read(record_id, &rcd->hdr, sizeof(*rcd) + + len = erst_read(record_id, &rcd->hdr, sizeof(*rcd) + erst_erange.size); if (uuid_le_cmp(rcd->hdr.creator_id, CPER_CREATOR_PSTORE) != 0) goto skip; - raw_spin_unlock_irqrestore(&erst_lock, flags); *id = record_id; if (uuid_le_cmp(rcd->sec_hdr.section_type, @@ -1005,7 +1026,8 @@ skip: time->tv_sec = 0; time->tv_nsec = 0; - return len - sizeof(*rcd); +out: + return (rc < 0) ? rc : (len - sizeof(*rcd)); } static u64 erst_writer(enum pstore_type_id type, size_t size) diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c index 912403c..f2c3ff2 100644 --- a/fs/pstore/platform.c +++ b/fs/pstore/platform.c @@ -156,17 +156,23 @@ void pstore_get_records(void) u64 id; enum pstore_type_id type; struct timespec time; - int failed = 0; + int failed = 0, rc; if (!psi) return; mutex_lock(&psinfo->buf_mutex); + rc = psi->open(psi); + if (rc) + goto out; + while ((size = psi->read(&id, &type, &time)) > 0) { if (pstore_mkfile(type, psi->name, id, psi->buf, (size_t)size, time, psi->erase)) failed++; } + psi->close(psi); +out: mutex_unlock(&psinfo->buf_mutex); if (failed) diff --git a/include/linux/pstore.h b/include/linux/pstore.h index 14ce2f5..2455ef2 100644 --- a/include/linux/pstore.h +++ b/include/linux/pstore.h @@ -35,6 +35,8 @@ struct pstore_info { struct mutex buf_mutex; /* serialize access to 'buf' */ char *buf; size_t bufsize; + int (*open)(struct pstore_info *psi); + int (*close)(struct pstore_info *psi); ssize_t (*read)(u64 *id, enum pstore_type_id *type, struct timespec *time); u64 (*write)(enum pstore_type_id type, size_t size); -- 1.7.5.185.g0b9dee -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/