From: Linus Torvalds Date: Tue, 1 Nov 2011 17:52:29 +0000 (-0700) Subject: Merge branch 'pstore' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux X-Git-Tag: v3.2-rc1~103 X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=commitdiff_plain;h=1c398651518c7e25a9fb3f08b456c73d5ca22469;hp=f470f8d4e702593ee1d0852871ad80373bce707b Merge branch 'pstore' of git://git./linux/kernel/git/aegl/linux * 'pstore' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux: pstore: make pstore write function return normal success/fail value pstore: change mutex locking to spin_locks pstore: defer inserting OOPS entries into pstore --- diff --git a/drivers/acpi/apei/erst.c b/drivers/acpi/apei/erst.c index 2ca59dc69f7f..127408069ca7 100644 --- a/drivers/acpi/apei/erst.c +++ b/drivers/acpi/apei/erst.c @@ -933,7 +933,7 @@ 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, struct pstore_info *psi); -static u64 erst_writer(enum pstore_type_id type, unsigned int part, +static int erst_writer(enum pstore_type_id type, u64 *id, unsigned int part, size_t size, struct pstore_info *psi); static int erst_clearer(enum pstore_type_id type, u64 id, struct pstore_info *psi); @@ -1040,11 +1040,12 @@ out: return (rc < 0) ? rc : (len - sizeof(*rcd)); } -static u64 erst_writer(enum pstore_type_id type, unsigned int part, +static int erst_writer(enum pstore_type_id type, u64 *id, unsigned int part, size_t size, struct pstore_info *psi) { struct cper_pstore_record *rcd = (struct cper_pstore_record *) (erst_info.buf - sizeof(*rcd)); + int ret; memset(rcd, 0, sizeof(*rcd)); memcpy(rcd->hdr.signature, CPER_SIG_RECORD, CPER_SIG_SIZE); @@ -1079,9 +1080,10 @@ static u64 erst_writer(enum pstore_type_id type, unsigned int part, } rcd->sec_hdr.section_severity = CPER_SEV_FATAL; - erst_write(&rcd->hdr); + ret = erst_write(&rcd->hdr); + *id = rcd->hdr.record_id; - return rcd->hdr.record_id; + return ret; } static int erst_clearer(enum pstore_type_id type, u64 id, @@ -1165,7 +1167,7 @@ static int __init erst_init(void) goto err_release_erange; buf = kmalloc(erst_erange.size, GFP_KERNEL); - mutex_init(&erst_info.buf_mutex); + spin_lock_init(&erst_info.buf_lock); if (buf) { erst_info.buf = buf + sizeof(struct cper_pstore_record); erst_info.bufsize = erst_erange.size - diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c index eb80b549ed8d..8370f72d87ff 100644 --- a/drivers/firmware/efivars.c +++ b/drivers/firmware/efivars.c @@ -490,8 +490,8 @@ static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type, return 0; } -static u64 efi_pstore_write(enum pstore_type_id type, unsigned int part, - size_t size, struct pstore_info *psi) +static int efi_pstore_write(enum pstore_type_id type, u64 *id, + unsigned int part, size_t size, struct pstore_info *psi) { char name[DUMP_NAME_LEN]; char stub_name[DUMP_NAME_LEN]; @@ -499,7 +499,7 @@ static u64 efi_pstore_write(enum pstore_type_id type, unsigned int part, efi_guid_t vendor = LINUX_EFI_CRASH_GUID; struct efivars *efivars = psi->data; struct efivar_entry *entry, *found = NULL; - int i; + int i, ret = 0; sprintf(stub_name, "dump-type%u-%u-", type, part); sprintf(name, "%s%lu", stub_name, get_seconds()); @@ -548,18 +548,19 @@ static u64 efi_pstore_write(enum pstore_type_id type, unsigned int part, efivar_unregister(found); if (size) - efivar_create_sysfs_entry(efivars, + ret = efivar_create_sysfs_entry(efivars, utf16_strsize(efi_name, DUMP_NAME_LEN * 2), efi_name, &vendor); - return part; + *id = part; + return ret; }; static int efi_pstore_erase(enum pstore_type_id type, u64 id, struct pstore_info *psi) { - efi_pstore_write(type, id, 0, psi); + efi_pstore_write(type, &id, (unsigned int)id, 0, psi); return 0; } @@ -580,8 +581,8 @@ static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type, return -1; } -static u64 efi_pstore_write(enum pstore_type_id type, unsigned int part, - size_t size, struct pstore_info *psi) +static int efi_pstore_write(enum pstore_type_id type, u64 *id, + unsigned int part, size_t size, struct pstore_info *psi) { return 0; } @@ -978,7 +979,7 @@ int register_efivars(struct efivars *efivars, if (efivars->efi_pstore_info.buf) { efivars->efi_pstore_info.bufsize = 1024; efivars->efi_pstore_info.data = efivars; - mutex_init(&efivars->efi_pstore_info.buf_mutex); + spin_lock_init(&efivars->efi_pstore_info.buf_lock); pstore_register(&efivars->efi_pstore_info); } diff --git a/fs/pstore/inode.c b/fs/pstore/inode.c index 893b961dcfd8..379a02dc1217 100644 --- a/fs/pstore/inode.c +++ b/fs/pstore/inode.c @@ -24,6 +24,7 @@ #include #include #include +#include #include #include #include @@ -32,13 +33,18 @@ #include #include #include +#include #include #include "internal.h" #define PSTORE_NAMELEN 64 +static DEFINE_SPINLOCK(allpstore_lock); +static LIST_HEAD(allpstore); + struct pstore_private { + struct list_head list; struct pstore_info *psi; enum pstore_type_id type; u64 id; @@ -81,8 +87,16 @@ static int pstore_unlink(struct inode *dir, struct dentry *dentry) static void pstore_evict_inode(struct inode *inode) { + struct pstore_private *p = inode->i_private; + unsigned long flags; + end_writeback(inode); - kfree(inode->i_private); + if (p) { + spin_lock_irqsave(&allpstore_lock, flags); + list_del(&p->list); + spin_unlock_irqrestore(&allpstore_lock, flags); + kfree(p); + } } static const struct inode_operations pstore_dir_inode_operations = { @@ -182,9 +196,23 @@ int pstore_mkfile(enum pstore_type_id type, char *psname, u64 id, struct dentry *root = pstore_sb->s_root; struct dentry *dentry; struct inode *inode; - int rc; + int rc = 0; char name[PSTORE_NAMELEN]; - struct pstore_private *private; + struct pstore_private *private, *pos; + unsigned long flags; + + spin_lock_irqsave(&allpstore_lock, flags); + list_for_each_entry(pos, &allpstore, list) { + if (pos->type == type && + pos->id == id && + pos->psi == psi) { + rc = -EEXIST; + break; + } + } + spin_unlock_irqrestore(&allpstore_lock, flags); + if (rc) + return rc; rc = -ENOMEM; inode = pstore_get_inode(pstore_sb, root->d_inode, S_IFREG | 0444, 0); @@ -229,6 +257,10 @@ int pstore_mkfile(enum pstore_type_id type, char *psname, u64 id, d_add(dentry, inode); + spin_lock_irqsave(&allpstore_lock, flags); + list_add(&private->list, &allpstore); + spin_unlock_irqrestore(&allpstore_lock, flags); + mutex_unlock(&root->d_inode->i_mutex); return 0; @@ -277,7 +309,7 @@ int pstore_fill_super(struct super_block *sb, void *data, int silent) goto fail; } - pstore_get_records(); + pstore_get_records(0); return 0; fail: diff --git a/fs/pstore/internal.h b/fs/pstore/internal.h index 611c1b3c46fa..3bde461c3f34 100644 --- a/fs/pstore/internal.h +++ b/fs/pstore/internal.h @@ -1,5 +1,5 @@ extern void pstore_set_kmsg_bytes(int); -extern void pstore_get_records(void); +extern void pstore_get_records(int); extern int pstore_mkfile(enum pstore_type_id, char *psname, u64 id, char *data, size_t size, struct timespec time, struct pstore_info *psi); diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c index c5300ec31696..2bd620f0d796 100644 --- a/fs/pstore/platform.c +++ b/fs/pstore/platform.c @@ -25,11 +25,29 @@ #include #include #include +#include #include #include +#include +#include #include "internal.h" +/* + * We defer making "oops" entries appear in pstore - see + * whether the system is actually still running well enough + * to let someone see the entry + */ +#define PSTORE_INTERVAL (60 * HZ) + +static int pstore_new_entry; + +static void pstore_timefunc(unsigned long); +static DEFINE_TIMER(pstore_timer, pstore_timefunc, 0, 0); + +static void pstore_dowork(struct work_struct *); +static DECLARE_WORK(pstore_work, pstore_dowork); + /* * pstore_lock just protects "psinfo" during * calls to pstore_register() @@ -69,15 +87,22 @@ static void pstore_dump(struct kmsg_dumper *dumper, unsigned long size, total = 0; char *dst, *why; u64 id; - int hsize; + int hsize, ret; unsigned int part = 1; + unsigned long flags = 0; + int is_locked = 0; if (reason < ARRAY_SIZE(reason_str)) why = reason_str[reason]; else why = "Unknown"; - mutex_lock(&psinfo->buf_mutex); + if (in_nmi()) { + is_locked = spin_trylock(&psinfo->buf_lock); + if (!is_locked) + pr_err("pstore dump routine blocked in NMI, may corrupt error record\n"); + } else + spin_lock_irqsave(&psinfo->buf_lock, flags); oopscount++; while (total < kmsg_bytes) { dst = psinfo->buf; @@ -97,18 +122,20 @@ static void pstore_dump(struct kmsg_dumper *dumper, memcpy(dst, s1 + s1_start, l1_cpy); memcpy(dst + l1_cpy, s2 + s2_start, l2_cpy); - id = psinfo->write(PSTORE_TYPE_DMESG, part, + ret = psinfo->write(PSTORE_TYPE_DMESG, &id, part, hsize + l1_cpy + l2_cpy, psinfo); - if (reason == KMSG_DUMP_OOPS && pstore_is_mounted()) - pstore_mkfile(PSTORE_TYPE_DMESG, psinfo->name, id, - psinfo->buf, hsize + l1_cpy + l2_cpy, - CURRENT_TIME, psinfo); + if (ret == 0 && reason == KMSG_DUMP_OOPS && pstore_is_mounted()) + pstore_new_entry = 1; l1 -= l1_cpy; l2 -= l2_cpy; total += l1_cpy + l2_cpy; part++; } - mutex_unlock(&psinfo->buf_mutex); + if (in_nmi()) { + if (is_locked) + spin_unlock(&psinfo->buf_lock); + } else + spin_unlock_irqrestore(&psinfo->buf_lock, flags); } static struct kmsg_dumper pstore_dumper = { @@ -148,19 +175,24 @@ int pstore_register(struct pstore_info *psi) } if (pstore_is_mounted()) - pstore_get_records(); + pstore_get_records(0); kmsg_dump_register(&pstore_dumper); + pstore_timer.expires = jiffies + PSTORE_INTERVAL; + add_timer(&pstore_timer); + return 0; } EXPORT_SYMBOL_GPL(pstore_register); /* - * Read all the records from the persistent store. Create and - * file files in our filesystem. + * Read all the records from the persistent store. Create + * files in our filesystem. Don't warn about -EEXIST errors + * when we are re-scanning the backing store looking to add new + * error records. */ -void pstore_get_records(void) +void pstore_get_records(int quiet) { struct pstore_info *psi = psinfo; ssize_t size; @@ -168,36 +200,55 @@ void pstore_get_records(void) enum pstore_type_id type; struct timespec time; int failed = 0, rc; + unsigned long flags; if (!psi) return; - mutex_lock(&psinfo->buf_mutex); + spin_lock_irqsave(&psinfo->buf_lock, flags); rc = psi->open(psi); if (rc) goto out; while ((size = psi->read(&id, &type, &time, psi)) > 0) { - if (pstore_mkfile(type, psi->name, id, psi->buf, (size_t)size, - time, psi)) + rc = pstore_mkfile(type, psi->name, id, psi->buf, (size_t)size, + time, psi); + if (rc && (rc != -EEXIST || !quiet)) failed++; } psi->close(psi); out: - mutex_unlock(&psinfo->buf_mutex); + spin_unlock_irqrestore(&psinfo->buf_lock, flags); if (failed) printk(KERN_WARNING "pstore: failed to load %d record(s) from '%s'\n", failed, psi->name); } +static void pstore_dowork(struct work_struct *work) +{ + pstore_get_records(1); +} + +static void pstore_timefunc(unsigned long dummy) +{ + if (pstore_new_entry) { + pstore_new_entry = 0; + schedule_work(&pstore_work); + } + + mod_timer(&pstore_timer, jiffies + PSTORE_INTERVAL); +} + /* * Call platform driver to write a record to the * persistent store. */ int pstore_write(enum pstore_type_id type, char *buf, size_t size) { - u64 id; + u64 id; + int ret; + unsigned long flags; if (!psinfo) return -ENODEV; @@ -205,13 +256,13 @@ int pstore_write(enum pstore_type_id type, char *buf, size_t size) if (size > psinfo->bufsize) return -EFBIG; - mutex_lock(&psinfo->buf_mutex); + spin_lock_irqsave(&psinfo->buf_lock, flags); memcpy(psinfo->buf, buf, size); - id = psinfo->write(type, 0, size, psinfo); - if (pstore_is_mounted()) + ret = psinfo->write(type, &id, 0, size, psinfo); + if (ret == 0 && pstore_is_mounted()) pstore_mkfile(PSTORE_TYPE_DMESG, psinfo->name, id, psinfo->buf, size, CURRENT_TIME, psinfo); - mutex_unlock(&psinfo->buf_mutex); + spin_unlock_irqrestore(&psinfo->buf_lock, flags); return 0; } diff --git a/include/linux/pstore.h b/include/linux/pstore.h index cc03bbf5c4b8..ea567321ae3c 100644 --- a/include/linux/pstore.h +++ b/include/linux/pstore.h @@ -32,15 +32,15 @@ enum pstore_type_id { struct pstore_info { struct module *owner; char *name; - struct mutex buf_mutex; /* serialize access to 'buf' */ + spinlock_t buf_lock; /* 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, struct pstore_info *psi); - u64 (*write)(enum pstore_type_id type, unsigned int part, - size_t size, struct pstore_info *psi); + int (*write)(enum pstore_type_id type, u64 *id, + unsigned int part, size_t size, struct pstore_info *psi); int (*erase)(enum pstore_type_id type, u64 id, struct pstore_info *psi); void *data;