kernel-fxtec-pro1x/fs/orangefs/super.c
Martin Brandenburg cefdc26e86 orangefs: move features validation to fix filesystem hang
Without this fix (and another to the userspace component itself
described later), the kernel will be unable to process any OrangeFS
requests after the userspace component is restarted (due to a crash or
at the administrator's behest).

The bug here is that inside orangefs_remount, the orangefs_request_mutex
is locked.  When the userspace component restarts while the filesystem
is mounted, it sends a ORANGEFS_DEV_REMOUNT_ALL ioctl to the device,
which causes the kernel to send it a few requests aimed at synchronizing
the state between the two.  While this is happening the
orangefs_request_mutex is locked to prevent any other requests going
through.

This is only half of the bugfix.  The other half is in the userspace
component which outright ignores(!) requests made before it considers
the filesystem remounted, which is after the ioctl returns.  Of course
the ioctl doesn't return until after the userspace component responds to
the request it ignores.  The userspace component has been changed to
allow ORANGEFS_VFS_OP_FEATURES regardless of the mount status.

Mike Marshall says:
 "I've tested this patch against the fixed userspace part. This patch is
  real important, I hope it can make it into 4.11...

  Here's what happens when the userspace daemon is restarted, without
  the patch:

    =============================================
    [ INFO: possible recursive locking detected ]
    [   4.10.0-00007-ge98bdb3 #1 Not tainted    ]
    ---------------------------------------------
    pvfs2-client-co/29032 is trying to acquire lock:
     (orangefs_request_mutex){+.+.+.}, at: service_operation+0x3c7/0x7b0 [orangefs]
                  but task is already holding lock:
     (orangefs_request_mutex){+.+.+.}, at: dispatch_ioctl_command+0x1bf/0x330 [orangefs]

    CPU: 0 PID: 29032 Comm: pvfs2-client-co Not tainted 4.10.0-00007-ge98bdb3 #1
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.3-1.fc25 04/01/2014
    Call Trace:
     __lock_acquire+0x7eb/0x1290
     lock_acquire+0xe8/0x1d0
     mutex_lock_killable_nested+0x6f/0x6e0
     service_operation+0x3c7/0x7b0 [orangefs]
     orangefs_remount+0xea/0x150 [orangefs]
     dispatch_ioctl_command+0x227/0x330 [orangefs]
     orangefs_devreq_ioctl+0x29/0x70 [orangefs]
     do_vfs_ioctl+0xa3/0x6e0
     SyS_ioctl+0x79/0x90"

Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Acked-by: Mike Marshall <hubcap@omnibond.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-04-07 13:41:22 -07:00

598 lines
16 KiB
C

/*
* (C) 2001 Clemson University and The University of Chicago
*
* See COPYING in top-level directory.
*/
#include "protocol.h"
#include "orangefs-kernel.h"
#include "orangefs-bufmap.h"
#include <linux/parser.h>
/* a cache for orangefs-inode objects (i.e. orangefs inode private data) */
static struct kmem_cache *orangefs_inode_cache;
/* list for storing orangefs specific superblocks in use */
LIST_HEAD(orangefs_superblocks);
DEFINE_SPINLOCK(orangefs_superblocks_lock);
enum {
Opt_intr,
Opt_acl,
Opt_local_lock,
Opt_err
};
static const match_table_t tokens = {
{ Opt_acl, "acl" },
{ Opt_intr, "intr" },
{ Opt_local_lock, "local_lock" },
{ Opt_err, NULL }
};
uint64_t orangefs_features;
static int parse_mount_options(struct super_block *sb, char *options,
int silent)
{
struct orangefs_sb_info_s *orangefs_sb = ORANGEFS_SB(sb);
substring_t args[MAX_OPT_ARGS];
char *p;
/*
* Force any potential flags that might be set from the mount
* to zero, ie, initialize to unset.
*/
sb->s_flags &= ~MS_POSIXACL;
orangefs_sb->flags &= ~ORANGEFS_OPT_INTR;
orangefs_sb->flags &= ~ORANGEFS_OPT_LOCAL_LOCK;
while ((p = strsep(&options, ",")) != NULL) {
int token;
if (!*p)
continue;
token = match_token(p, tokens, args);
switch (token) {
case Opt_acl:
sb->s_flags |= MS_POSIXACL;
break;
case Opt_intr:
orangefs_sb->flags |= ORANGEFS_OPT_INTR;
break;
case Opt_local_lock:
orangefs_sb->flags |= ORANGEFS_OPT_LOCAL_LOCK;
break;
default:
goto fail;
}
}
return 0;
fail:
if (!silent)
gossip_err("Error: mount option [%s] is not supported.\n", p);
return -EINVAL;
}
static void orangefs_inode_cache_ctor(void *req)
{
struct orangefs_inode_s *orangefs_inode = req;
inode_init_once(&orangefs_inode->vfs_inode);
init_rwsem(&orangefs_inode->xattr_sem);
orangefs_inode->vfs_inode.i_version = 1;
}
static struct inode *orangefs_alloc_inode(struct super_block *sb)
{
struct orangefs_inode_s *orangefs_inode;
orangefs_inode = kmem_cache_alloc(orangefs_inode_cache, GFP_KERNEL);
if (orangefs_inode == NULL) {
gossip_err("Failed to allocate orangefs_inode\n");
return NULL;
}
/*
* We want to clear everything except for rw_semaphore and the
* vfs_inode.
*/
memset(&orangefs_inode->refn.khandle, 0, 16);
orangefs_inode->refn.fs_id = ORANGEFS_FS_ID_NULL;
orangefs_inode->last_failed_block_index_read = 0;
memset(orangefs_inode->link_target, 0, sizeof(orangefs_inode->link_target));
orangefs_inode->pinode_flags = 0;
gossip_debug(GOSSIP_SUPER_DEBUG,
"orangefs_alloc_inode: allocated %p\n",
&orangefs_inode->vfs_inode);
return &orangefs_inode->vfs_inode;
}
static void orangefs_i_callback(struct rcu_head *head)
{
struct inode *inode = container_of(head, struct inode, i_rcu);
struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
kmem_cache_free(orangefs_inode_cache, orangefs_inode);
}
static void orangefs_destroy_inode(struct inode *inode)
{
struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
gossip_debug(GOSSIP_SUPER_DEBUG,
"%s: deallocated %p destroying inode %pU\n",
__func__, orangefs_inode, get_khandle_from_ino(inode));
call_rcu(&inode->i_rcu, orangefs_i_callback);
}
/*
* NOTE: information filled in here is typically reflected in the
* output of the system command 'df'
*/
static int orangefs_statfs(struct dentry *dentry, struct kstatfs *buf)
{
int ret = -ENOMEM;
struct orangefs_kernel_op_s *new_op = NULL;
int flags = 0;
struct super_block *sb = NULL;
sb = dentry->d_sb;
gossip_debug(GOSSIP_SUPER_DEBUG,
"orangefs_statfs: called on sb %p (fs_id is %d)\n",
sb,
(int)(ORANGEFS_SB(sb)->fs_id));
new_op = op_alloc(ORANGEFS_VFS_OP_STATFS);
if (!new_op)
return ret;
new_op->upcall.req.statfs.fs_id = ORANGEFS_SB(sb)->fs_id;
if (ORANGEFS_SB(sb)->flags & ORANGEFS_OPT_INTR)
flags = ORANGEFS_OP_INTERRUPTIBLE;
ret = service_operation(new_op, "orangefs_statfs", flags);
if (new_op->downcall.status < 0)
goto out_op_release;
gossip_debug(GOSSIP_SUPER_DEBUG,
"%s: got %ld blocks available | "
"%ld blocks total | %ld block size | "
"%ld files total | %ld files avail\n",
__func__,
(long)new_op->downcall.resp.statfs.blocks_avail,
(long)new_op->downcall.resp.statfs.blocks_total,
(long)new_op->downcall.resp.statfs.block_size,
(long)new_op->downcall.resp.statfs.files_total,
(long)new_op->downcall.resp.statfs.files_avail);
buf->f_type = sb->s_magic;
memcpy(&buf->f_fsid, &ORANGEFS_SB(sb)->fs_id, sizeof(buf->f_fsid));
buf->f_bsize = new_op->downcall.resp.statfs.block_size;
buf->f_namelen = ORANGEFS_NAME_MAX;
buf->f_blocks = (sector_t) new_op->downcall.resp.statfs.blocks_total;
buf->f_bfree = (sector_t) new_op->downcall.resp.statfs.blocks_avail;
buf->f_bavail = (sector_t) new_op->downcall.resp.statfs.blocks_avail;
buf->f_files = (sector_t) new_op->downcall.resp.statfs.files_total;
buf->f_ffree = (sector_t) new_op->downcall.resp.statfs.files_avail;
buf->f_frsize = sb->s_blocksize;
out_op_release:
op_release(new_op);
gossip_debug(GOSSIP_SUPER_DEBUG, "orangefs_statfs: returning %d\n", ret);
return ret;
}
/*
* Remount as initiated by VFS layer. We just need to reparse the mount
* options, no need to signal pvfs2-client-core about it.
*/
static int orangefs_remount_fs(struct super_block *sb, int *flags, char *data)
{
gossip_debug(GOSSIP_SUPER_DEBUG, "orangefs_remount_fs: called\n");
return parse_mount_options(sb, data, 1);
}
/*
* Remount as initiated by pvfs2-client-core on restart. This is used to
* repopulate mount information left from previous pvfs2-client-core.
*
* the idea here is that given a valid superblock, we're
* re-initializing the user space client with the initial mount
* information specified when the super block was first initialized.
* this is very different than the first initialization/creation of a
* superblock. we use the special service_priority_operation to make
* sure that the mount gets ahead of any other pending operation that
* is waiting for servicing. this means that the pvfs2-client won't
* fail to start several times for all other pending operations before
* the client regains all of the mount information from us.
* NOTE: this function assumes that the request_mutex is already acquired!
*/
int orangefs_remount(struct orangefs_sb_info_s *orangefs_sb)
{
struct orangefs_kernel_op_s *new_op;
int ret = -EINVAL;
gossip_debug(GOSSIP_SUPER_DEBUG, "orangefs_remount: called\n");
new_op = op_alloc(ORANGEFS_VFS_OP_FS_MOUNT);
if (!new_op)
return -ENOMEM;
strncpy(new_op->upcall.req.fs_mount.orangefs_config_server,
orangefs_sb->devname,
ORANGEFS_MAX_SERVER_ADDR_LEN);
gossip_debug(GOSSIP_SUPER_DEBUG,
"Attempting ORANGEFS Remount via host %s\n",
new_op->upcall.req.fs_mount.orangefs_config_server);
/*
* we assume that the calling function has already acquired the
* request_mutex to prevent other operations from bypassing
* this one
*/
ret = service_operation(new_op, "orangefs_remount",
ORANGEFS_OP_PRIORITY | ORANGEFS_OP_NO_MUTEX);
gossip_debug(GOSSIP_SUPER_DEBUG,
"orangefs_remount: mount got return value of %d\n",
ret);
if (ret == 0) {
/*
* store the id assigned to this sb -- it's just a
* short-lived mapping that the system interface uses
* to map this superblock to a particular mount entry
*/
orangefs_sb->id = new_op->downcall.resp.fs_mount.id;
orangefs_sb->mount_pending = 0;
}
op_release(new_op);
if (orangefs_userspace_version >= 20906) {
new_op = op_alloc(ORANGEFS_VFS_OP_FEATURES);
if (!new_op)
return -ENOMEM;
new_op->upcall.req.features.features = 0;
ret = service_operation(new_op, "orangefs_features",
ORANGEFS_OP_PRIORITY | ORANGEFS_OP_NO_MUTEX);
if (!ret)
orangefs_features =
new_op->downcall.resp.features.features;
else
orangefs_features = 0;
op_release(new_op);
} else {
orangefs_features = 0;
}
return ret;
}
int fsid_key_table_initialize(void)
{
return 0;
}
void fsid_key_table_finalize(void)
{
}
/* Called whenever the VFS dirties the inode in response to atime updates */
static void orangefs_dirty_inode(struct inode *inode, int flags)
{
struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
gossip_debug(GOSSIP_SUPER_DEBUG,
"orangefs_dirty_inode: %pU\n",
get_khandle_from_ino(inode));
SetAtimeFlag(orangefs_inode);
}
static const struct super_operations orangefs_s_ops = {
.alloc_inode = orangefs_alloc_inode,
.destroy_inode = orangefs_destroy_inode,
.dirty_inode = orangefs_dirty_inode,
.drop_inode = generic_delete_inode,
.statfs = orangefs_statfs,
.remount_fs = orangefs_remount_fs,
.show_options = generic_show_options,
};
static struct dentry *orangefs_fh_to_dentry(struct super_block *sb,
struct fid *fid,
int fh_len,
int fh_type)
{
struct orangefs_object_kref refn;
if (fh_len < 5 || fh_type > 2)
return NULL;
ORANGEFS_khandle_from(&(refn.khandle), fid->raw, 16);
refn.fs_id = (u32) fid->raw[4];
gossip_debug(GOSSIP_SUPER_DEBUG,
"fh_to_dentry: handle %pU, fs_id %d\n",
&refn.khandle,
refn.fs_id);
return d_obtain_alias(orangefs_iget(sb, &refn));
}
static int orangefs_encode_fh(struct inode *inode,
__u32 *fh,
int *max_len,
struct inode *parent)
{
int len = parent ? 10 : 5;
int type = 1;
struct orangefs_object_kref refn;
if (*max_len < len) {
gossip_lerr("fh buffer is too small for encoding\n");
*max_len = len;
type = 255;
goto out;
}
refn = ORANGEFS_I(inode)->refn;
ORANGEFS_khandle_to(&refn.khandle, fh, 16);
fh[4] = refn.fs_id;
gossip_debug(GOSSIP_SUPER_DEBUG,
"Encoding fh: handle %pU, fsid %u\n",
&refn.khandle,
refn.fs_id);
if (parent) {
refn = ORANGEFS_I(parent)->refn;
ORANGEFS_khandle_to(&refn.khandle, (char *) fh + 20, 16);
fh[9] = refn.fs_id;
type = 2;
gossip_debug(GOSSIP_SUPER_DEBUG,
"Encoding parent: handle %pU, fsid %u\n",
&refn.khandle,
refn.fs_id);
}
*max_len = len;
out:
return type;
}
static const struct export_operations orangefs_export_ops = {
.encode_fh = orangefs_encode_fh,
.fh_to_dentry = orangefs_fh_to_dentry,
};
static int orangefs_fill_sb(struct super_block *sb,
struct orangefs_fs_mount_response *fs_mount,
void *data, int silent)
{
int ret = -EINVAL;
struct inode *root = NULL;
struct dentry *root_dentry = NULL;
struct orangefs_object_kref root_object;
/* alloc and init our private orangefs sb info */
sb->s_fs_info = kzalloc(sizeof(struct orangefs_sb_info_s), GFP_KERNEL);
if (!ORANGEFS_SB(sb))
return -ENOMEM;
ORANGEFS_SB(sb)->sb = sb;
ORANGEFS_SB(sb)->root_khandle = fs_mount->root_khandle;
ORANGEFS_SB(sb)->fs_id = fs_mount->fs_id;
ORANGEFS_SB(sb)->id = fs_mount->id;
if (data) {
ret = parse_mount_options(sb, data, silent);
if (ret)
return ret;
}
/* Hang the xattr handlers off the superblock */
sb->s_xattr = orangefs_xattr_handlers;
sb->s_magic = ORANGEFS_SUPER_MAGIC;
sb->s_op = &orangefs_s_ops;
sb->s_d_op = &orangefs_dentry_operations;
sb->s_blocksize = orangefs_bufmap_size_query();
sb->s_blocksize_bits = orangefs_bufmap_shift_query();
sb->s_maxbytes = MAX_LFS_FILESIZE;
root_object.khandle = ORANGEFS_SB(sb)->root_khandle;
root_object.fs_id = ORANGEFS_SB(sb)->fs_id;
gossip_debug(GOSSIP_SUPER_DEBUG,
"get inode %pU, fsid %d\n",
&root_object.khandle,
root_object.fs_id);
root = orangefs_iget(sb, &root_object);
if (IS_ERR(root))
return PTR_ERR(root);
gossip_debug(GOSSIP_SUPER_DEBUG,
"Allocated root inode [%p] with mode %x\n",
root,
root->i_mode);
/* allocates and places root dentry in dcache */
root_dentry = d_make_root(root);
if (!root_dentry)
return -ENOMEM;
sb->s_export_op = &orangefs_export_ops;
sb->s_root = root_dentry;
return 0;
}
struct dentry *orangefs_mount(struct file_system_type *fst,
int flags,
const char *devname,
void *data)
{
int ret = -EINVAL;
struct super_block *sb = ERR_PTR(-EINVAL);
struct orangefs_kernel_op_s *new_op;
struct dentry *d = ERR_PTR(-EINVAL);
gossip_debug(GOSSIP_SUPER_DEBUG,
"orangefs_mount: called with devname %s\n",
devname);
if (!devname) {
gossip_err("ERROR: device name not specified.\n");
return ERR_PTR(-EINVAL);
}
new_op = op_alloc(ORANGEFS_VFS_OP_FS_MOUNT);
if (!new_op)
return ERR_PTR(-ENOMEM);
strncpy(new_op->upcall.req.fs_mount.orangefs_config_server,
devname,
ORANGEFS_MAX_SERVER_ADDR_LEN);
gossip_debug(GOSSIP_SUPER_DEBUG,
"Attempting ORANGEFS Mount via host %s\n",
new_op->upcall.req.fs_mount.orangefs_config_server);
ret = service_operation(new_op, "orangefs_mount", 0);
gossip_debug(GOSSIP_SUPER_DEBUG,
"orangefs_mount: mount got return value of %d\n", ret);
if (ret)
goto free_op;
if (new_op->downcall.resp.fs_mount.fs_id == ORANGEFS_FS_ID_NULL) {
gossip_err("ERROR: Retrieved null fs_id\n");
ret = -EINVAL;
goto free_op;
}
sb = sget(fst, NULL, set_anon_super, flags, NULL);
if (IS_ERR(sb)) {
d = ERR_CAST(sb);
goto free_op;
}
ret = orangefs_fill_sb(sb,
&new_op->downcall.resp.fs_mount, data,
flags & MS_SILENT ? 1 : 0);
if (ret) {
d = ERR_PTR(ret);
goto free_op;
}
/*
* on successful mount, store the devname and data
* used
*/
strncpy(ORANGEFS_SB(sb)->devname,
devname,
ORANGEFS_MAX_SERVER_ADDR_LEN);
/* mount_pending must be cleared */
ORANGEFS_SB(sb)->mount_pending = 0;
/*
* finally, add this sb to our list of known orangefs
* sb's
*/
gossip_debug(GOSSIP_SUPER_DEBUG,
"Adding SB %p to orangefs superblocks\n",
ORANGEFS_SB(sb));
spin_lock(&orangefs_superblocks_lock);
list_add_tail(&ORANGEFS_SB(sb)->list, &orangefs_superblocks);
spin_unlock(&orangefs_superblocks_lock);
op_release(new_op);
if (orangefs_userspace_version >= 20906) {
new_op = op_alloc(ORANGEFS_VFS_OP_FEATURES);
if (!new_op)
return ERR_PTR(-ENOMEM);
new_op->upcall.req.features.features = 0;
ret = service_operation(new_op, "orangefs_features", 0);
orangefs_features = new_op->downcall.resp.features.features;
op_release(new_op);
} else {
orangefs_features = 0;
}
return dget(sb->s_root);
free_op:
gossip_err("orangefs_mount: mount request failed with %d\n", ret);
if (ret == -EINVAL) {
gossip_err("Ensure that all orangefs-servers have the same FS configuration files\n");
gossip_err("Look at pvfs2-client-core log file (typically /tmp/pvfs2-client.log) for more details\n");
}
op_release(new_op);
return d;
}
void orangefs_kill_sb(struct super_block *sb)
{
gossip_debug(GOSSIP_SUPER_DEBUG, "orangefs_kill_sb: called\n");
/* provided sb cleanup */
kill_anon_super(sb);
/*
* issue the unmount to userspace to tell it to remove the
* dynamic mount info it has for this superblock
*/
orangefs_unmount_sb(sb);
/* remove the sb from our list of orangefs specific sb's */
spin_lock(&orangefs_superblocks_lock);
__list_del_entry(&ORANGEFS_SB(sb)->list); /* not list_del_init */
ORANGEFS_SB(sb)->list.prev = NULL;
spin_unlock(&orangefs_superblocks_lock);
/*
* make sure that ORANGEFS_DEV_REMOUNT_ALL loop that might've seen us
* gets completed before we free the dang thing.
*/
mutex_lock(&orangefs_request_mutex);
mutex_unlock(&orangefs_request_mutex);
/* free the orangefs superblock private data */
kfree(ORANGEFS_SB(sb));
}
int orangefs_inode_cache_initialize(void)
{
orangefs_inode_cache = kmem_cache_create("orangefs_inode_cache",
sizeof(struct orangefs_inode_s),
0,
ORANGEFS_CACHE_CREATE_FLAGS,
orangefs_inode_cache_ctor);
if (!orangefs_inode_cache) {
gossip_err("Cannot create orangefs_inode_cache\n");
return -ENOMEM;
}
return 0;
}
int orangefs_inode_cache_finalize(void)
{
kmem_cache_destroy(orangefs_inode_cache);
return 0;
}