From 8d38d74b648513dd8ed8bd2b67d899208ef4e09e Mon Sep 17 00:00:00 2001 From: Chen Gong Date: Mon, 16 May 2011 10:58:57 -0700 Subject: 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 Signed-off-by: Tony Luck --- drivers/acpi/apei/erst.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers') diff --git a/drivers/acpi/apei/erst.c b/drivers/acpi/apei/erst.c index d6cb0ff6988e..d5a89d067f98 100644 --- 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; -- cgit v1.2.3 From 06cf91b4b4aafa50ee0a94c81d2c6922a18af242 Mon Sep 17 00:00:00 2001 From: Chen Gong Date: Mon, 16 May 2011 11:00:27 -0700 Subject: pstore: fix pstore filesystem mount/remount issue 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 Signed-off-by: Tony Luck --- drivers/acpi/apei/erst.c | 48 +++++++++++++++++++++++++++++++++++------------- fs/pstore/platform.c | 8 +++++++- include/linux/pstore.h | 2 ++ 3 files changed, 44 insertions(+), 14 deletions(-) (limited to 'drivers') diff --git a/drivers/acpi/apei/erst.c b/drivers/acpi/apei/erst.c index d5a89d067f98..ddb68c4f8d3e 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 912403c2a93d..f2c3ff20ea68 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 14ce2f5d08af..2455ef2683f0 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); -- cgit v1.2.3 From f5ec25deb2471bd49e907ab2f9ef6f860eb7cf95 Mon Sep 17 00:00:00 2001 From: Chen Gong Date: Mon, 16 May 2011 11:01:39 -0700 Subject: pstore: fix potential logic issue in pstore read interface 1) in the calling of erst_read, the parameter of buffer size maybe overflows and cause crash 2) the return value of erst_read should be checked more strictly Signed-off-by: Chen Gong Signed-off-by: Tony Luck --- drivers/acpi/apei/erst.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'drivers') diff --git a/drivers/acpi/apei/erst.c b/drivers/acpi/apei/erst.c index ddb68c4f8d3e..e6cef8e1b534 100644 --- a/drivers/acpi/apei/erst.c +++ b/drivers/acpi/apei/erst.c @@ -1006,7 +1006,14 @@ skip: } len = erst_read(record_id, &rcd->hdr, sizeof(*rcd) + - erst_erange.size); + erst_info.bufsize); + /* The record may be cleared by others, try read next record */ + if (len == -ENOENT) + goto skip; + else if (len < 0) { + rc = -1; + goto out; + } if (uuid_le_cmp(rcd->hdr.creator_id, CPER_CREATOR_PSTORE) != 0) goto skip; -- cgit v1.2.3 From 5d2a8342f64e93c217fcbf3206ec9ae770b1413d Mon Sep 17 00:00:00 2001 From: "Luck, Tony" Date: Wed, 13 Apr 2011 10:48:12 -0700 Subject: pstore: Fix Kconfig dependencies for apei->pstore Geert Uytterhoeven ran a dependency checker which kicked out this warning: + warning: (ACPI_APEI) selects PSTORE which has unmet direct dependencies (MISC_FILESYSTEMS): => N/A Randy confirmed that the fix was to "select MISC_FILESYSTEMS" too. Tested-by: Randy Dunlap Signed-off-by: Tony Luck --- drivers/acpi/apei/Kconfig | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers') diff --git a/drivers/acpi/apei/Kconfig b/drivers/acpi/apei/Kconfig index 66a03caa2ad9..f739a70b1c70 100644 --- a/drivers/acpi/apei/Kconfig +++ b/drivers/acpi/apei/Kconfig @@ -1,5 +1,6 @@ config ACPI_APEI bool "ACPI Platform Error Interface (APEI)" + select MISC_FILESYSTEMS select PSTORE depends on X86 help -- cgit v1.2.3