- 根目录:
- fs
- ceph
- dir.c
#include <linux/ceph/ceph_debug.h>
#include <linux/spinlock.h>
#include <linux/fs_struct.h>
#include <linux/namei.h>
#include <linux/slab.h>
#include <linux/sched.h>
#include "super.h"
#include "mds_client.h"
/*
* Directory operations: readdir, lookup, create, link, unlink,
* rename, etc.
*/
/*
* Ceph MDS operations are specified in terms of a base ino and
* relative path. Thus, the client can specify an operation on a
* specific inode (e.g., a getattr due to fstat(2)), or as a path
* relative to, say, the root directory.
*
* Normally, we limit ourselves to strict inode ops (no path component)
* or dentry operations (a single path component relative to an ino). The
* exception to this is open_root_dentry(), which will open the mount
* point by name.
*/
const struct inode_operations ceph_dir_iops;
const struct file_operations ceph_dir_fops;
const struct dentry_operations ceph_dentry_ops;
/*
* Initialize ceph dentry state.
*/
int ceph_init_dentry(struct dentry *dentry)
{
struct ceph_dentry_info *di;
if (dentry->d_fsdata)
return 0;
if (dentry->d_parent == NULL || /* nfs fh_to_dentry */
ceph_snap(dentry->d_parent->d_inode) == CEPH_NOSNAP)
d_set_d_op(dentry, &ceph_dentry_ops);
else if (ceph_snap(dentry->d_parent->d_inode) == CEPH_SNAPDIR)
d_set_d_op(dentry, &ceph_snapdir_dentry_ops);
else
d_set_d_op(dentry, &ceph_snap_dentry_ops);
di = kmem_cache_alloc(ceph_dentry_cachep, GFP_NOFS | __GFP_ZERO);
if (!di)
return -ENOMEM; /* oh well */
spin_lock(&dentry->d_lock);
if (dentry->d_fsdata) {
/* lost a race */
kmem_cache_free(ceph_dentry_cachep, di);
goto out_unlock;
}
di->dentry = dentry;
di->lease_session = NULL;
dentry->d_fsdata = di;
dentry->d_time = jiffies;
ceph_dentry_lru_add(dentry);
out_unlock:
spin_unlock(&dentry->d_lock);
return 0;
}
/*
* for readdir, we encode the directory frag and offset within that
* frag into f_pos.
*/
static unsigned fpos_frag(loff_t p)
{
return p >> 32;
}
static unsigned fpos_off(loff_t p)
{
return p & 0xffffffff;
}
/*
* When possible, we try to satisfy a readdir by peeking at the
* dcache. We make this work by carefully ordering dentries on
* d_u.d_child when we initially get results back from the MDS, and
* falling back to a "normal" sync readdir if any dentries in the dir
* are dropped.
*
* I_COMPLETE tells indicates we have all dentries in the dir. It is
* defined IFF we hold CEPH_CAP_FILE_SHARED (which will be revoked by
* the MDS if/when the directory is modified).
*/
static int __dcache_readdir(struct file *filp,
void *dirent, filldir_t filldir)
{
struct ceph_file_info *fi = filp->private_data;
struct dentry *parent = filp->f_dentry;
struct inode *dir = parent->d_inode;
struct list_head *p;
struct dentry *dentry, *last;
struct ceph_dentry_info *di;
int err = 0;
/* claim ref on last dentry we returned */
last = fi->dentry;
fi->dentry = NULL;
dout("__dcache_readdir %p at %llu (last %p)\n", dir, filp->f_pos,
last);
spin_lock(&parent->d_lock);
/* start at beginning? */
if (filp->f_pos == 2 || last == NULL ||
filp->f_pos < ceph_dentry(last)->offset) {
if (list_empty(&parent->d_subdirs))
goto out_unlock;
p = parent->d_subdirs.prev;
dout(" initial p %p/%p\n", p->prev, p->next);
} else {
p = last->d_u.d_child.prev;
}
more:
dentry = list_entry(p, struct dentry, d_u.d_child);
di = ceph_dentry(dentry);
while (1) {
dout(" p %p/%p %s d_subdirs %p/%p\n", p->prev, p->next,
d_unhashed(dentry) ? "!hashed" : "hashed",
parent->d_subdirs.prev, parent->d_subdirs.next);
if (p == &parent->d_subdirs) {
fi->at_end = 1;
goto out_unlock;
}
spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED);
if (!d_unhashed(dentry) && dentry->d_inode &&
ceph_snap(dentry->d_inode) != CEPH_SNAPDIR &&
ceph_ino(dentry->d_inode) != CEPH_INO_CEPH &&
filp->f_pos <= di->offset)
break;
dout(" skipping %p %.*s at %llu (%llu)%s%s\n", dentry,
dentry->d_name.len, dentry->d_name.name, di->offset,
filp->f_pos, d_unhashed(dentry) ? " unhashed" : "",
!dentry->d_inode ? " null" : "");
spin_unlock(&dentry->d_lock);
p = p->prev;
dentry = list_entry(p, struct dentry, d_u.d_child);
di = ceph_dentry(dentry);
}
dget_dlock(dentry);
spin_unlock(&dentry->d_lock);
spin_unlock(&parent->d_lock);
dout(" %llu (%llu) dentry %p %.*s %p\n", di->offset, filp->f_pos,
dentry, dentry->d_name.len, dentry->d_name.name, dentry->d_inode);
filp->f_pos = di->offset;
err = filldir(dirent, dentry->d_name.name,
dentry->d_name.len, di->offset,
ceph_translate_ino(dentry->d_sb, dentry->d_inode->i_ino),
dentry->d_inode->i_mode >> 12);
if (last) {
if (err < 0) {
/* remember our position */
fi->dentry = last;
fi->next_offset = di->offset;
} else {
dput(last);
}
}
last = dentry;
if (err < 0)
goto out;
filp->f_pos++;
/* make sure a dentry wasn't dropped while we didn't have parent lock */
if (!ceph_i_test(dir, CEPH_I_COMPLETE)) {
dout(" lost I_COMPLETE on %p; falling back to mds\n", dir);
err = -EAGAIN;
goto out;
}
spin_lock(&parent->d_lock);
p = p->prev; /* advance to next dentry */
goto more;
out_unlock:
spin_unlock(&parent->d_lock);
out:
if (last)
dput(last);
return err;
}
/*
* make note of the last dentry we read, so we can
* continue at the same lexicographical point,
* regardless of what dir changes take place on the
* server.
*/
static int note_last_dentry(struct ceph_file_info *fi, const char *name,
int len)
{
kfree(fi->last_name);
fi->last_name = kmalloc(len+1, GFP_NOFS);
if (!fi->last_name)
return -ENOMEM;
memcpy(fi->last_name, name, len);
fi->last_name[len] = 0;
dout("note_last_dentry '%s'\n", fi->last_name);
return 0;
}
static int ceph_readdir(struct file *filp, void *dirent, filldir_t filldir)
{
struct ceph_file_info *fi = filp->private_data;
struct inode *inode = filp->f_dentry->d_inode;
struct ceph_inode_info *ci = ceph_inode(inode);
struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
struct ceph_mds_client *mdsc = fsc->mdsc;
unsigned frag = fpos_frag(filp->f_pos);
int off = fpos_off(filp->f_pos);
int err;
u32 ftype;
struct ceph_mds_reply_info_parsed *rinfo;
const int max_entries = fsc->mount_options->max_readdir;
const int max_bytes = fsc->mount_options->max_readdir_bytes;
dout("readdir %p filp %p frag %u off %u\n", inode, filp, frag, off);
if (fi->at_end)
return 0;
/* always start with . and .. */
if (filp->f_pos == 0) {
/* note dir version at start of readdir so we can tell
* if any dentries get dropped */
fi->dir_release_count = ci->i_release_count;
dout("readdir off 0 -> '.'\n");
if (filldir(dirent, ".", 1, ceph_make_fpos(0, 0),
ceph_translate_ino(inode->i_sb, inode->i_ino),
inode->i_mode >> 12) < 0)
return 0;
filp->f_pos = 1;
off = 1;
}
if (filp->f_pos == 1) {
ino_t ino = filp->f_dentry->d_parent->d_inode->i_ino;
dout("readdir off 1 -> '..'\n");
if (filldir(dirent, "..", 2, ceph_make_fpos(0, 1),
ceph_translate_ino(inode->i_sb, ino),
inode->i_mode >> 12) < 0)
return 0;
filp->f_pos = 2;
off = 2;
}
/* can we use the dcache? */
spin_lock(&inode->i_lock);
if ((filp->f_pos == 2 || fi->dentry) &&
!ceph_test_mount_opt(fsc, NOASYNCREADDIR) &&
ceph_snap(inode) != CEPH_SNAPDIR &&
(ci->i_ceph_flags & CEPH_I_COMPLETE) &&
__ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1)) {
spin_unlock(&inode->i_lock);
err = __dcache_readdir(filp, dirent, filldir);
if (err != -EAGAIN)
return err;
} else {
spin_unlock(&inode->i_lock);
}
if (fi->dentry) {
err = note_last_dentry(fi, fi->dentry->d_name.name,
fi->dentry->d_name.len);
if (err)
return err;
dput(fi->dentry);
fi->dentry = NULL;
}
/* proceed with a normal readdir */
more:
/* do we have the correct frag content buffered? */
if (fi->frag != frag || fi->last_readdir == NULL) {
struct ceph_mds_request *req;
int op = ceph_snap(inode) == CEPH_SNAPDIR ?
CEPH_MDS_OP_LSSNAP : CEPH_MDS_OP_READDIR;
/* discard old result, if any */
if (fi->last_readdir) {
ceph_mdsc_put_request(fi->last_readdir);
fi->last_readdir = NULL;
}
/* requery frag tree, as the frag topology may have changed */
frag = ceph_choose_frag(ceph_inode(inode), frag, NULL, NULL);
dout("readdir fetching %llx.%llx frag %x offset '%s'\n",
ceph_vinop(inode), frag, fi->last_name);
req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
if (IS_ERR(req))
return PTR_ERR(req);
req->r_inode = igrab(inode);
req->r_dentry = dget(filp->f_dentry);
/* hints to request -> mds selection code */
req->r_direct_mode = USE_AUTH_MDS;
req->r_direct_hash = ceph_frag_value(frag);
req->r_direct_is_hash = true;
req->r_path2 = kstrdup(fi->last_name, GFP_NOFS);
req->r_readdir_offset = fi->next_offset;
req->r_args.readdir.frag = cpu_to_le32(frag);
req->r_args.readdir.max_entries = cpu_to_le32(max_entries);
req->r_args.readdir.max_bytes = cpu_to_le32(max_bytes);
req->r_num_caps = max_entries + 1;
err = ceph_mdsc_do_request(mdsc, NULL, req);
if (err < 0) {
ceph_mdsc_put_request(req);
return err;
}
dout("readdir got and parsed readdir result=%d"
" on frag %x, end=%d, complete=%d\n", err, frag,
(int)req->r_reply_info.dir_end,
(int)req->r_reply_info.dir_complete);
if (!req->r_did_prepopulate) {
dout("readdir !did_prepopulate");
fi->dir_release_count--; /* preclude I_COMPLETE */
}
/* note next offset and last dentry name */
fi->offset = fi->next_offset;
fi->last_readdir = req;
if (req->r_reply_info.dir_end) {
kfree(fi->last_name);
fi->last_name = NULL;
if (ceph_frag_is_rightmost(frag))
fi->next_offset = 2;
else
fi->next_offset = 0;
} else {
rinfo = &req->r_reply_info;
err = note_last_dentry(fi,
rinfo->dir_dname[rinfo->dir_nr-1],
rinfo->dir_dname_len[rinfo->dir_nr-1]);
if (err)
return err;
fi->next_offset += rinfo->dir_nr;
}
}
rinfo = &fi->last_readdir->r_reply_info;
dout("readdir frag %x num %d off %d chunkoff %d\n", frag,
rinfo->dir_nr, off, fi->offset);
while (off - fi->offset >= 0 && off - fi->offset < rinfo->dir_nr) {
u64 pos = ceph_make_fpos(frag, off);
struct ceph_mds_reply_inode *in =
rinfo->dir_in[off - fi->offset].in;
struct ceph_vino vino;
ino_t ino;
dout("readdir off %d (%d/%d) -> %lld '%.*s' %p\n",
off, off - fi->offset, rinfo->dir_nr, pos,
rinfo->dir_dname_len[off - fi->offset],
rinfo->dir_dname[off - fi->offset], in);
BUG_ON(!in);
ftype = le32_to_cpu(in->mode) >> 12;
vino.ino = le64_to_cpu(in->ino);
vino.snap = le64_to_cpu(in->snapid);
ino = ceph_vino_to_ino(vino);
if (filldir(dirent,
rinfo->dir_dname[off - fi->offset],
rinfo->dir_dname_len[off - fi->offset],
pos,
ceph_translate_ino(inode->i_sb, ino), ftype) < 0) {
dout("filldir stopping us...\n");
return 0;
}
off++;
filp->f_pos = pos + 1;
}
if (fi->last_name) {
ceph_mdsc_put_request(fi->last_readdir);
fi->last_readdir = NULL;
goto more;
}
/* more frags? */
if (!ceph_frag_is_rightmost(frag)) {
frag = ceph_frag_next(frag);
off = 0;
filp->f_pos = ceph_make_fpos(frag, off);
dout("readdir next frag is %x\n", frag);
goto more;
}
fi->at_end = 1;
/*
* if dir_release_count still matches the dir, no dentries
* were released during the whole readdir, and we should have
* the complete dir contents in our cache.
*/
spin_lock(&inode->i_lock);
if (ci->i_release_count == fi->dir_release_count) {
dout(" marking %p complete\n", inode);
/* ci->i_ceph_flags |= CEPH_I_COMPLETE; */
ci->i_max_offset = filp->f_pos;
}
spin_unlock(&inode->i_lock);
dout("readdir %p filp %p done.\n", inode, filp);
return 0;
}
static void reset_readdir(struct ceph_file_info *fi)
{
if (fi->last_readdir) {
ceph_mdsc_put_request(fi->last_readdir);
fi->last_readdir = NULL;
}
kfree(fi->last_name);
fi->last_name = NULL;
fi->next_offset = 2; /* compensate for . and .. */
if (fi->dentry) {
dput(fi->dentry);
fi->dentry = NULL;
}
fi->at_end = 0;
}
static loff_t ceph_dir_llseek(struct file *file, loff_t offset, int origin)
{
struct ceph_file_info *fi = file->private_data;
struct inode *inode = file->f_mapping->host;
loff_t old_offset = offset;
loff_t retval;
mutex_lock(&inode->i_mutex);
switch (origin) {
case SEEK_END:
offset += inode->i_size + 2; /* FIXME */
break;
case SEEK_CUR:
offset += file->f_pos;
}
retval = -EINVAL;
if (offset >= 0 && offset <= inode->i_sb->s_maxbytes) {
if (offset != file->f_pos) {
file->f_pos = offset;
file->f_version = 0;
fi->at_end = 0;
}
retval = offset;
/*
* discard buffered readdir content on seekdir(0), or
* seek to new frag, or seek prior to current chunk.
*/
if (offset == 0 ||
fpos_frag(offset) != fpos_frag(old_offset) ||
fpos_off(offset) < fi->offset) {
dout("dir_llseek dropping %p content\n", file);
reset_readdir(fi);
}
/* bump dir_release_count if we did a forward seek */
if (offset > old_offset)
fi->dir_release_count--;
}
mutex_unlock(&inode->i_mutex);
return retval;
}
/*
* Process result of a lookup/open request.
*
* Mainly, make sure we return the final req->r_dentry (if it already
* existed) in place of the original VFS-provided dentry when they
* differ.
*
* Gracefully handle the case where the MDS replies with -ENOENT and
* no trace (which it may do, at its discretion, e.g., if it doesn't
* care to issue a lease on the negative dentry).
*/
struct dentry *ceph_finish_lookup(struct ceph_mds_request *req,
struct dentry *dentry, int err)
{
struct ceph_fs_client *fsc = ceph_sb_to_client(dentry->d_sb);
struct inode *parent = dentry->d_parent->d_inode;
/* .snap dir? */
if (err == -ENOENT &&
ceph_snap(parent) == CEPH_NOSNAP &&
strcmp(dentry->d_name.name,
fsc->mount_options->snapdir_name) == 0) {
struct inode *inode = ceph_get_snapdir(parent);
dout("ENOENT on snapdir %p '%.*s', linking to snapdir %p\n",
dentry, dentry->d_name.len, dentry->d_name.name, inode);
BUG_ON(!d_unhashed(dentry));
d_add(dentry, inode);
err = 0;
}
if (err == -ENOENT) {
/* no trace? */
err = 0;
if (!req->r_reply_info.head->is_dentry) {
dout("ENOENT and no trace, dentry %p inode %p\n",
dentry, dentry->d_inode);
if (dentry->d_inode) {
d_drop(dentry);
err = -ENOENT;
} else {
d_add(dentry, NULL);
}
}
}
if (err)
dentry = ERR_PTR(err);
else if (dentry != req->r_dentry)
dentry = dget(req->r_dentry); /* we got spliced */
else
dentry = NULL;
return dentry;
}
static int is_root_ceph_dentry(struct inode *inode, struct dentry *dentry)
{
return ceph_ino(inode) == CEPH_INO_ROOT &&
strncmp(dentry->d_name.name, ".ceph", 5) == 0;
}
/*
* Look up a single dir entry. If there is a lookup intent, inform
* the MDS so that it gets our 'caps wanted' value in a single op.
*/
static struct dentry *ceph_lookup(struct inode *dir, struct dentry *dentry,
struct nameidata *nd)
{
struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
struct ceph_mds_client *mdsc = fsc->mdsc;
struct ceph_mds_request *req;
int op;
int err;
dout("lookup %p dentry %p '%.*s'\n",
dir, dentry, dentry->d_name.len, dentry->d_name.name);
if (dentry->d_name.len > NAME_MAX)
return ERR_PTR(-ENAMETOOLONG);
err = ceph_init_dentry(dentry);
if (err < 0)
return ERR_PTR(err);
/* open (but not create!) intent? */
if (nd &&
(nd->flags & LOOKUP_OPEN) &&
(nd->flags & LOOKUP_CONTINUE) == 0 && /* only open last component */
!(nd->intent.open.flags & O_CREAT)) {
int mode = nd->intent.open.create_mode & ~current->fs->umask;
return ceph_lookup_open(dir, dentry, nd, mode, 1);
}
/* can we conclude ENOENT locally? */
if (dentry->d_inode == NULL) {
struct ceph_inode_info *ci = ceph_inode(dir);
struct ceph_dentry_info *di = ceph_dentry(dentry);
spin_lock(&dir->i_lock);
dout(" dir %p flags are %d\n", dir, ci->i_ceph_flags);
if (strncmp(dentry->d_name.name,
fsc->mount_options->snapdir_name,
dentry->d_name.len) &&
!is_root_ceph_dentry(dir, dentry) &&
(ci->i_ceph_flags & CEPH_I_COMPLETE) &&
(__ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1))) {
spin_unlock(&dir->i_lock);
dout(" dir %p complete, -ENOENT\n", dir);
d_add(dentry, NULL);
di->lease_shared_gen = ci->i_shared_gen;
return NULL;
}
spin_unlock(&dir->i_lock);
}
op = ceph_snap(dir) == CEPH_SNAPDIR ?
CEPH_MDS_OP_LOOKUPSNAP : CEPH_MDS_OP_LOOKUP;
req = ceph_mdsc_create_request(mdsc, op, USE_ANY_MDS);
if (IS_ERR(req))
return ERR_CAST(req);
req->r_dentry = dget(dentry);
req->r_num_caps = 2;
/* we only need inode linkage */
req->r_args.getattr.mask = cpu_to_le32(CEPH_STAT_CAP_INODE);
req->r_locked_dir = dir;
err = ceph_mdsc_do_request(mdsc, NULL, req);
dentry = ceph_finish_lookup(req, dentry, err);
ceph_mdsc_put_request(req); /* will dput(dentry) */
dout("lookup result=%p\n", dentry);
return dentry;
}
/*
* If we do a create but get no trace back from the MDS, follow up with
* a lookup (the VFS expects us to link up the provided dentry).
*/
int ceph_handle_notrace_create(struct inode *dir, struct dentry *dentry)
{
struct dentry *result = ceph_lookup(dir, dentry, NULL);
if (result && !IS_ERR(result)) {
/*
* We created the item, then did a lookup, and found
* it was already linked to another inode we already
* had in our cache (and thus got spliced). Link our
* dentry to that inode, but don't hash it, just in
* case the VFS wants to dereference it.
*/
BUG_ON(!result->d_inode);
d_instantiate(dentry, result->d_inode);
return 0;
}
return PTR_ERR(result);
}
static int ceph_mknod(struct inode *dir, struct dentry *dentry,
int mode, dev_t rdev)
{
struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
struct ceph_mds_client *mdsc = fsc->mdsc;
struct ceph_mds_request *req;
int err;
if (ceph_snap(dir) != CEPH_NOSNAP)
return -EROFS;
dout("mknod in dir %p dentry %p mode 0%o rdev %d\n",
dir, dentry, mode, rdev);
req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_MKNOD, USE_AUTH_MDS);
if (IS_ERR(req)) {
d_drop(dentry);
return PTR_ERR(req);
}
req->r_dentry = dget(dentry);
req->r_num_caps = 2;
req->r_locked_dir = dir;
req->r_args.mknod.mode = cpu_to_le32(mode);
req->r_args.mknod.rdev = cpu_to_le32(rdev);
req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
err = ceph_mdsc_do_request(mdsc, dir, req);
if (!err && !req->r_reply_info.head->is_dentry)
err = ceph_handle_notrace_create(dir, dentry);
ceph_mdsc_put_request(req);
if (err)
d_drop(dentry);
return err;
}
static int ceph_create(struct inode *dir, struct dentry *dentry, int mode,
struct nameidata *nd)
{
dout("create in dir %p dentry %p name '%.*s'\n",
dir, dentry, dentry->d_name.len, dentry->d_name.name);
if (ceph_snap(dir) != CEPH_NOSNAP)
return -EROFS;
if (nd) {
BUG_ON((nd->flags & LOOKUP_OPEN) == 0);
dentry = ceph_lookup_open(dir, dentry, nd, mode, 0);
/* hrm, what should i do here if we get aliased? */
if (IS_ERR(dentry))
return PTR_ERR(dentry);
return 0;
}
/* fall back to mknod */
return ceph_mknod(dir, dentry, (mode & ~S_IFMT) | S_IFREG, 0);
}
static int ceph_symlink(struct inode *dir, struct dentry *dentry,
const char *dest)
{
struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
struct ceph_mds_client *mdsc = fsc->mdsc;
struct ceph_mds_request *req;
int err;
if (ceph_snap(dir) != CEPH_NOSNAP)
return -EROFS;
dout("symlink in dir %p dentry %p to '%s'\n", dir, dentry, dest);
req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SYMLINK, USE_AUTH_MDS);
if (IS_ERR(req)) {
d_drop(dentry);
return PTR_ERR(req);
}
req->r_dentry = dget(dentry);
req->r_num_caps = 2;
req->r_path2 = kstrdup(dest, GFP_NOFS);
req->r_locked_dir = dir;
req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
err = ceph_mdsc_do_request(mdsc, dir, req);
if (!err && !req->r_reply_info.head->is_dentry)
err = ceph_handle_notrace_create(dir, dentry);
ceph_mdsc_put_request(req);
if (err)
d_drop(dentry);
return err;
}
static int ceph_mkdir(struct inode *dir, struct dentry *dentry, int mode)
{
struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
struct ceph_mds_client *mdsc = fsc->mdsc;
struct ceph_mds_request *req;
int err = -EROFS;
int op;
if (ceph_snap(dir) == CEPH_SNAPDIR) {
/* mkdir .snap/foo is a MKSNAP */
op = CEPH_MDS_OP_MKSNAP;
dout("mksnap dir %p snap '%.*s' dn %p\n", dir,
dentry->d_name.len, dentry->d_name.name, dentry);
} else if (ceph_snap(dir) == CEPH_NOSNAP) {
dout("mkdir dir %p dn %p mode 0%o\n", dir, dentry, mode);
op = CEPH_MDS_OP_MKDIR;
} else {
goto out;
}
req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
if (IS_ERR(req)) {
err = PTR_ERR(req);
goto out;
}
req->r_dentry = dget(dentry);
req->r_num_caps = 2;
req->r_locked_dir = dir;
req->r_args.mkdir.mode = cpu_to_le32(mode);
req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
err = ceph_mdsc_do_request(mdsc, dir, req);
if (!err && !req->r_reply_info.head->is_dentry)
err = ceph_handle_notrace_create(dir, dentry);
ceph_mdsc_put_request(req);
out:
if (err < 0)
d_drop(dentry);
return err;
}
static int ceph_link(struct dentry *old_dentry, struct inode *dir,
struct dentry *dentry)
{
struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
struct ceph_mds_client *mdsc = fsc->mdsc;
struct ceph_mds_request *req;
int err;
if (ceph_snap(dir) != CEPH_NOSNAP)
return -EROFS;
dout("link in dir %p old_dentry %p dentry %p\n", dir,
old_dentry, dentry);
req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LINK, USE_AUTH_MDS);
if (IS_ERR(req)) {
d_drop(dentry);
return PTR_ERR(req);
}
req->r_dentry = dget(dentry);
req->r_num_caps = 2;
req->r_old_dentry = dget(old_dentry); /* or inode? hrm. */
req->r_locked_dir = dir;
req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
err = ceph_mdsc_do_request(mdsc, dir, req);
if (err)
d_drop(dentry);
else if (!req->r_reply_info.head->is_dentry)
d_instantiate(dentry, igrab(old_dentry->d_inode));
ceph_mdsc_put_request(req);
return err;
}
/*
* For a soon-to-be unlinked file, drop the AUTH_RDCACHE caps. If it
* looks like the link count will hit 0, drop any other caps (other
* than PIN) we don't specifically want (due to the file still being
* open).
*/
static int drop_caps_for_unlink(struct inode *inode)
{
struct ceph_inode_info *ci = ceph_inode(inode);
int drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL;
spin_lock(&inode->i_lock);
if (inode->i_nlink == 1) {
drop |= ~(__ceph_caps_wanted(ci) | CEPH_CAP_PIN);
ci->i_ceph_flags |= CEPH_I_NODELAY;
}
spin_unlock(&inode->i_lock);
return drop;
}
/*
* rmdir and unlink are differ only by the metadata op code
*/
static int ceph_unlink(struct inode *dir, struct dentry *dentry)
{
struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
struct ceph_mds_client *mdsc = fsc->mdsc;
struct inode *inode = dentry->d_inode;
struct ceph_mds_request *req;
int err = -EROFS;
int op;
if (ceph_snap(dir) == CEPH_SNAPDIR) {
/* rmdir .snap/foo is RMSNAP */
dout("rmsnap dir %p '%.*s' dn %p\n", dir, dentry->d_name.len,
dentry->d_name.name, dentry);
op = CEPH_MDS_OP_RMSNAP;
} else if (ceph_snap(dir) == CEPH_NOSNAP) {
dout("unlink/rmdir dir %p dn %p inode %p\n",
dir, dentry, inode);
op = ((dentry->d_inode->i_mode & S_IFMT) == S_IFDIR) ?
CEPH_MDS_OP_RMDIR : CEPH_MDS_OP_UNLINK;
} else
goto out;
req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
if (IS_ERR(req)) {
err = PTR_ERR(req);
goto out;
}
req->r_dentry = dget(dentry);
req->r_num_caps = 2;
req->r_locked_dir = dir;
req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
req->r_inode_drop = drop_caps_for_unlink(inode);
err = ceph_mdsc_do_request(mdsc, dir, req);
if (!err && !req->r_reply_info.head->is_dentry)
d_delete(dentry);
ceph_mdsc_put_request(req);
out:
return err;
}
static int ceph_rename(struct inode *old_dir, struct dentry *old_dentry,
struct inode *new_dir, struct dentry *new_dentry)
{
struct ceph_fs_client *fsc = ceph_sb_to_client(old_dir->i_sb);
struct ceph_mds_client *mdsc = fsc->mdsc;
struct ceph_mds_request *req;
int err;
if (ceph_snap(old_dir) != ceph_snap(new_dir))
return -EXDEV;
if (ceph_snap(old_dir) != CEPH_NOSNAP ||
ceph_snap(new_dir) != CEPH_NOSNAP)
return -EROFS;
dout("rename dir %p dentry %p to dir %p dentry %p\n",
old_dir, old_dentry, new_dir, new_dentry);
req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_RENAME, USE_AUTH_MDS);
if (IS_ERR(req))
return PTR_ERR(req);
req->r_dentry = dget(new_dentry);
req->r_num_caps = 2;
req->r_old_dentry = dget(old_dentry);
req->r_locked_dir = new_dir;
req->r_old_dentry_drop = CEPH_CAP_FILE_SHARED;
req->r_old_dentry_unless = CEPH_CAP_FILE_EXCL;
req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
/* release LINK_RDCACHE on source inode (mds will lock it) */
req->r_old_inode_drop = CEPH_CAP_LINK_SHARED;
if (new_dentry->d_inode)
req->r_inode_drop = drop_caps_for_unlink(new_dentry->d_inode);
err = ceph_mdsc_do_request(mdsc, old_dir, req);
if (!err && !req->r_reply_info.head->is_dentry) {
/*
* Normally d_move() is done by fill_trace (called by
* do_request, above). If there is no trace, we need
* to do it here.
*/
/* d_move screws up d_subdirs order */
ceph_i_clear(new_dir, CEPH_I_COMPLETE);
d_move(old_dentry, new_dentry);
/* ensure target dentry is invalidated, despite
rehashing bug in vfs_rename_dir */
ceph_invalidate_dentry_lease(new_dentry);
}
ceph_mdsc_put_request(req);
return err;
}
/*
* Ensure a dentry lease will no longer revalidate.
*/
void ceph_invalidate_dentry_lease(struct dentry *dentry)
{
spin_lock(&dentry->d_lock);
dentry->d_time = jiffies;
ceph_dentry(dentry)->lease_shared_gen = 0;
spin_unlock(&dentry->d_lock);
}
/*
* Check if dentry lease is valid. If not, delete the lease. Try to
* renew if the least is more than half up.
*/
static int dentry_lease_is_valid(struct dentry *dentry)
{
struct ceph_dentry_info *di;
struct ceph_mds_session *s;
int valid = 0;
u32 gen;
unsigned long ttl;
struct ceph_mds_session *session = NULL;
struct inode *dir = NULL;
u32 seq = 0;
spin_lock(&dentry->d_lock);
di = ceph_dentry(dentry);
if (di && di->lease_session) {
s = di->lease_session;
spin_lock(&s->s_cap_lock);
gen = s->s_cap_gen;
ttl = s->s_cap_ttl;
spin_unlock(&s->s_cap_lock);
if (di->lease_gen == gen &&
time_before(jiffies, dentry->d_time) &&
time_before(jiffies, ttl)) {
valid = 1;
if (di->lease_renew_after &&
time_after(jiffies, di->lease_renew_after)) {
/* we should renew */
dir = dentry->d_parent->d_inode;
session = ceph_get_mds_session(s);
seq = di->lease_seq;
di->lease_renew_after = 0;
di->lease_renew_from = jiffies;
}
}
}
spin_unlock(&dentry->d_lock);
if (session) {
ceph_mdsc_lease_send_msg(session, dir, dentry,
CEPH_MDS_LEASE_RENEW, seq);
ceph_put_mds_session(session);
}
dout("dentry_lease_is_valid - dentry %p = %d\n", dentry, valid);
return valid;
}
/*
* Check if directory-wide content lease/cap is valid.
*/
static int dir_lease_is_valid(struct inode *dir, struct dentry *dentry)
{
struct ceph_inode_info *ci = ceph_inode(dir);
struct ceph_dentry_info *di = ceph_dentry(dentry);
int valid = 0;
spin_lock(&dir->i_lock);
if (ci->i_shared_gen == di->lease_shared_gen)
valid = __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1);
spin_unlock(&dir->i_lock);
dout("dir_lease_is_valid dir %p v%u dentry %p v%u = %d\n",
dir, (unsigned)ci->i_shared_gen, dentry,
(unsigned)di->lease_shared_gen, valid);
return valid;
}
/*
* Check if cached dentry can be trusted.
*/
static int ceph_d_revalidate(struct dentry *dentry, struct nameidata *nd)
{
struct inode *dir;
if (nd && nd->flags & LOOKUP_RCU)
return -ECHILD;
dir = dentry->d_parent->d_inode;
dout("d_revalidate %p '%.*s' inode %p offset %lld\n", dentry,
dentry->d_name.len, dentry->d_name.name, dentry->d_inode,
ceph_dentry(dentry)->offset);
/* always trust cached snapped dentries, snapdir dentry */
if (ceph_snap(dir) != CEPH_NOSNAP) {
dout("d_revalidate %p '%.*s' inode %p is SNAPPED\n", dentry,
dentry->d_name.len, dentry->d_name.name, dentry->d_inode);
goto out_touch;
}
if (dentry->d_inode && ceph_snap(dentry->d_inode) == CEPH_SNAPDIR)
goto out_touch;
if (dentry_lease_is_valid(dentry) ||
dir_lease_is_valid(dir, dentry))
goto out_touch;
dout("d_revalidate %p invalid\n", dentry);
d_drop(dentry);
return 0;
out_touch:
ceph_dentry_lru_touch(dentry);
return 1;
}
/*
* Release our ceph_dentry_info.
*/
static void ceph_d_release(struct dentry *dentry)
{
struct ceph_dentry_info *di = ceph_dentry(dentry);
dout("d_release %p\n", dentry);
if (di) {
ceph_dentry_lru_del(dentry);
if (di->lease_session)
ceph_put_mds_session(di->lease_session);
kmem_cache_free(ceph_dentry_cachep, di);
dentry->d_fsdata = NULL;
}
}
static int ceph_snapdir_d_revalidate(struct dentry *dentry,
struct nameidata *nd)
{
/*
* Eventually, we'll want to revalidate snapped metadata
* too... probably...
*/
return 1;
}
/*
* read() on a dir. This weird interface hack only works if mounted
* with '-o dirstat'.
*/
static ssize_t ceph_read_dir(struct file *file, char __user *buf, size_t size,
loff_t *ppos)
{
struct ceph_file_info *cf = file->private_data;
struct inode *inode = file->f_dentry->d_inode;
struct ceph_inode_info *ci = ceph_inode(inode);
int left;
if (!ceph_test_mount_opt(ceph_sb_to_client(inode->i_sb), DIRSTAT))
return -EISDIR;
if (!cf->dir_info) {
cf->dir_info = kmalloc(1024, GFP_NOFS);
if (!cf->dir_info)
return -ENOMEM;
cf->dir_info_len =
sprintf(cf->dir_info,
"entries: %20lld\n"
" files: %20lld\n"
" subdirs: %20lld\n"
"rentries: %20lld\n"
" rfiles: %20lld\n"
" rsubdirs: %20lld\n"
"rbytes: %20lld\n"
"rctime: %10ld.%09ld\n",
ci->i_files + ci->i_subdirs,
ci->i_files,
ci->i_subdirs,
ci->i_rfiles + ci->i_rsubdirs,
ci->i_rfiles,
ci->i_rsubdirs,
ci->i_rbytes,
(long)ci->i_rctime.tv_sec,
(long)ci->i_rctime.tv_nsec);
}
if (*ppos >= cf->dir_info_len)
return 0;
size = min_t(unsigned, size, cf->dir_info_len-*ppos);
left = copy_to_user(buf, cf->dir_info + *ppos, size);
if (left == size)
return -EFAULT;
*ppos += (size - left);
return size - left;
}
/*
* an fsync() on a dir will wait for any uncommitted directory
* operations to commit.
*/
static int ceph_dir_fsync(struct file *file, int datasync)
{
struct inode *inode = file->f_path.dentry->d_inode;
struct ceph_inode_info *ci = ceph_inode(inode);
struct list_head *head = &ci->i_unsafe_dirops;
struct ceph_mds_request *req;
u64 last_tid;
int ret = 0;
dout("dir_fsync %p\n", inode);
spin_lock(&ci->i_unsafe_lock);
if (list_empty(head))
goto out;
req = list_entry(head->prev,
struct ceph_mds_request, r_unsafe_dir_item);
last_tid = req->r_tid;
do {
ceph_mdsc_get_request(req);
spin_unlock(&ci->i_unsafe_lock);
dout("dir_fsync %p wait on tid %llu (until %llu)\n",
inode, req->r_tid, last_tid);
if (req->r_timeout) {
ret = wait_for_completion_timeout(
&req->r_safe_completion, req->r_timeout);
if (ret > 0)
ret = 0;
else if (ret == 0)
ret = -EIO; /* timed out */
} else {
wait_for_completion(&req->r_safe_completion);
}
spin_lock(&ci->i_unsafe_lock);
ceph_mdsc_put_request(req);
if (ret || list_empty(head))
break;
req = list_entry(head->next,
struct ceph_mds_request, r_unsafe_dir_item);
} while (req->r_tid < last_tid);
out:
spin_unlock(&ci->i_unsafe_lock);
return ret;
}
/*
* We maintain a private dentry LRU.
*
* FIXME: this needs to be changed to a per-mds lru to be useful.
*/
void ceph_dentry_lru_add(struct dentry *dn)
{
struct ceph_dentry_info *di = ceph_dentry(dn);
struct ceph_mds_client *mdsc;
dout("dentry_lru_add %p %p '%.*s'\n", di, dn,
dn->d_name.len, dn->d_name.name);
if (di) {
mdsc = ceph_sb_to_client(dn->d_sb)->mdsc;
spin_lock(&mdsc->dentry_lru_lock);
list_add_tail(&di->lru, &mdsc->dentry_lru);
mdsc->num_dentry++;
spin_unlock(&mdsc->dentry_lru_lock);
}
}
void ceph_dentry_lru_touch(struct dentry *dn)
{
struct ceph_dentry_info *di = ceph_dentry(dn);
struct ceph_mds_client *mdsc;
dout("dentry_lru_touch %p %p '%.*s' (offset %lld)\n", di, dn,
dn->d_name.len, dn->d_name.name, di->offset);
if (di) {
mdsc = ceph_sb_to_client(dn->d_sb)->mdsc;
spin_lock(&mdsc->dentry_lru_lock);
list_move_tail(&di->lru, &mdsc->dentry_lru);
spin_unlock(&mdsc->dentry_lru_lock);
}
}
void ceph_dentry_lru_del(struct dentry *dn)
{
struct ceph_dentry_info *di = ceph_dentry(dn);
struct ceph_mds_client *mdsc;
dout("dentry_lru_del %p %p '%.*s'\n", di, dn,
dn->d_name.len, dn->d_name.name);
if (di) {
mdsc = ceph_sb_to_client(dn->d_sb)->mdsc;
spin_lock(&mdsc->dentry_lru_lock);
list_del_init(&di->lru);
mdsc->num_dentry--;
spin_unlock(&mdsc->dentry_lru_lock);
}
}
/*
* Return name hash for a given dentry. This is dependent on
* the parent directory's hash function.
*/
unsigned ceph_dentry_hash(struct dentry *dn)
{
struct inode *dir = dn->d_parent->d_inode;
struct ceph_inode_info *dci = ceph_inode(dir);
switch (dci->i_dir_layout.dl_dir_hash) {
case 0: /* for backward compat */
case CEPH_STR_HASH_LINUX:
return dn->d_name.hash;
default:
return ceph_str_hash(dci->i_dir_layout.dl_dir_hash,
dn->d_name.name, dn->d_name.len);
}
}
const struct file_operations ceph_dir_fops = {
.read = ceph_read_dir,
.readdir = ceph_readdir,
.llseek = ceph_dir_llseek,
.open = ceph_open,
.release = ceph_release,
.unlocked_ioctl = ceph_ioctl,
.fsync = ceph_dir_fsync,
};
const struct inode_operations ceph_dir_iops = {
.lookup = ceph_lookup,
.permission = ceph_permission,
.getattr = ceph_getattr,
.setattr = ceph_setattr,
.setxattr = ceph_setxattr,
.getxattr = ceph_getxattr,
.listxattr = ceph_listxattr,
.removexattr = ceph_removexattr,
.mknod = ceph_mknod,
.symlink = ceph_symlink,
.mkdir = ceph_mkdir,
.link = ceph_link,
.unlink = ceph_unlink,
.rmdir = ceph_unlink,
.rename = ceph_rename,
.create = ceph_create,
};
const struct dentry_operations ceph_dentry_ops = {
.d_revalidate = ceph_d_revalidate,
.d_release = ceph_d_release,
};
const struct dentry_operations ceph_snapdir_dentry_ops = {
.d_revalidate = ceph_snapdir_d_revalidate,
.d_release = ceph_d_release,
};
const struct dentry_operations ceph_snap_dentry_ops = {
.d_release = ceph_d_release,
};