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linux/fs/ceph/dir.c
Kirill A. Shutemov 09cbfeaf1a mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros 
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.

This promise never materialized.  And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE.  And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special.  They are
not.

The changes are pretty straight-forward:

 - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

 - page_cache_get() -> get_page();

 - page_cache_release() -> put_page();

This patch contains automated changes generated with coccinelle using
script below.  For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.

The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.

There are few places in the code where coccinelle didn't reach.  I'll
fix them manually in a separate patch.  Comments and documentation also
will be addressed with the separate patch.

virtual patch

@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT

@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE

@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK

@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)

@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)

@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-04 10:41:08 -07:00

1386 lines
37 KiB
C
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#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 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;
di = kmem_cache_zalloc(ceph_dentry_cachep, GFP_KERNEL);
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;
}
if (ceph_snap(d_inode(dentry->d_parent)) == CEPH_NOSNAP)
d_set_d_op(dentry, &ceph_dentry_ops);
else if (ceph_snap(d_inode(dentry->d_parent)) == CEPH_SNAPDIR)
d_set_d_op(dentry, &ceph_snapdir_dentry_ops);
else
d_set_d_op(dentry, &ceph_snap_dentry_ops);
di->dentry = dentry;
di->lease_session = NULL;
dentry->d_time = jiffies;
/* avoid reordering d_fsdata setup so that the check above is safe */
smp_mb();
dentry->d_fsdata = di;
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;
}
static int fpos_cmp(loff_t l, loff_t r)
{
int v = ceph_frag_compare(fpos_frag(l), fpos_frag(r));
if (v)
return v;
return (int)(fpos_off(l) - fpos_off(r));
}
/*
* 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, unsigned next_offset)
{
char *buf = kmalloc(len+1, GFP_KERNEL);
if (!buf)
return -ENOMEM;
kfree(fi->last_name);
fi->last_name = buf;
memcpy(fi->last_name, name, len);
fi->last_name[len] = 0;
fi->next_offset = next_offset;
dout("note_last_dentry '%s'\n", fi->last_name);
return 0;
}
/*
* When possible, we try to satisfy a readdir by peeking at the
* dcache. We make this work by carefully ordering dentries on
* 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.
*
* Complete dir indicates that 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 *file, struct dir_context *ctx,
u32 shared_gen)
{
struct ceph_file_info *fi = file->private_data;
struct dentry *parent = file->f_path.dentry;
struct inode *dir = d_inode(parent);
struct dentry *dentry, *last = NULL;
struct ceph_dentry_info *di;
unsigned nsize = PAGE_SIZE / sizeof(struct dentry *);
int err = 0;
loff_t ptr_pos = 0;
struct ceph_readdir_cache_control cache_ctl = {};
dout("__dcache_readdir %p v%u at %llu\n", dir, shared_gen, ctx->pos);
/* we can calculate cache index for the first dirfrag */
if (ceph_frag_is_leftmost(fpos_frag(ctx->pos))) {
cache_ctl.index = fpos_off(ctx->pos) - 2;
BUG_ON(cache_ctl.index < 0);
ptr_pos = cache_ctl.index * sizeof(struct dentry *);
}
while (true) {
pgoff_t pgoff;
bool emit_dentry;
if (ptr_pos >= i_size_read(dir)) {
fi->flags |= CEPH_F_ATEND;
err = 0;
break;
}
err = -EAGAIN;
pgoff = ptr_pos >> PAGE_SHIFT;
if (!cache_ctl.page || pgoff != page_index(cache_ctl.page)) {
ceph_readdir_cache_release(&cache_ctl);
cache_ctl.page = find_lock_page(&dir->i_data, pgoff);
if (!cache_ctl.page) {
dout(" page %lu not found\n", pgoff);
break;
}
/* reading/filling the cache are serialized by
* i_mutex, no need to use page lock */
unlock_page(cache_ctl.page);
cache_ctl.dentries = kmap(cache_ctl.page);
}
rcu_read_lock();
spin_lock(&parent->d_lock);
/* check i_size again here, because empty directory can be
* marked as complete while not holding the i_mutex. */
if (ceph_dir_is_complete_ordered(dir) &&
ptr_pos < i_size_read(dir))
dentry = cache_ctl.dentries[cache_ctl.index % nsize];
else
dentry = NULL;
spin_unlock(&parent->d_lock);
if (dentry && !lockref_get_not_dead(&dentry->d_lockref))
dentry = NULL;
rcu_read_unlock();
if (!dentry)
break;
emit_dentry = false;
di = ceph_dentry(dentry);
spin_lock(&dentry->d_lock);
if (di->lease_shared_gen == shared_gen &&
d_really_is_positive(dentry) &&
ceph_snap(d_inode(dentry)) != CEPH_SNAPDIR &&
ceph_ino(d_inode(dentry)) != CEPH_INO_CEPH &&
fpos_cmp(ctx->pos, di->offset) <= 0) {
emit_dentry = true;
}
spin_unlock(&dentry->d_lock);
if (emit_dentry) {
dout(" %llu (%llu) dentry %p %pd %p\n", di->offset, ctx->pos,
dentry, dentry, d_inode(dentry));
ctx->pos = di->offset;
if (!dir_emit(ctx, dentry->d_name.name,
dentry->d_name.len,
ceph_translate_ino(dentry->d_sb,
d_inode(dentry)->i_ino),
d_inode(dentry)->i_mode >> 12)) {
dput(dentry);
err = 0;
break;
}
ctx->pos++;
if (last)
dput(last);
last = dentry;
} else {
dput(dentry);
}
cache_ctl.index++;
ptr_pos += sizeof(struct dentry *);
}
ceph_readdir_cache_release(&cache_ctl);
if (last) {
int ret;
di = ceph_dentry(last);
ret = note_last_dentry(fi, last->d_name.name, last->d_name.len,
fpos_off(di->offset) + 1);
if (ret < 0)
err = ret;
dput(last);
}
return err;
}
static int ceph_readdir(struct file *file, struct dir_context *ctx)
{
struct ceph_file_info *fi = file->private_data;
struct inode *inode = file_inode(file);
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(ctx->pos);
int off = fpos_off(ctx->pos);
int err;
u32 ftype;
struct ceph_mds_reply_info_parsed *rinfo;
dout("readdir %p file %p frag %u off %u\n", inode, file, frag, off);
if (fi->flags & CEPH_F_ATEND)
return 0;
/* always start with . and .. */
if (ctx->pos == 0) {
dout("readdir off 0 -> '.'\n");
if (!dir_emit(ctx, ".", 1,
ceph_translate_ino(inode->i_sb, inode->i_ino),
inode->i_mode >> 12))
return 0;
ctx->pos = 1;
off = 1;
}
if (ctx->pos == 1) {
ino_t ino = parent_ino(file->f_path.dentry);
dout("readdir off 1 -> '..'\n");
if (!dir_emit(ctx, "..", 2,
ceph_translate_ino(inode->i_sb, ino),
inode->i_mode >> 12))
return 0;
ctx->pos = 2;
off = 2;
}
/* can we use the dcache? */
spin_lock(&ci->i_ceph_lock);
if (ceph_test_mount_opt(fsc, DCACHE) &&
!ceph_test_mount_opt(fsc, NOASYNCREADDIR) &&
ceph_snap(inode) != CEPH_SNAPDIR &&
__ceph_dir_is_complete_ordered(ci) &&
__ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1)) {
u32 shared_gen = ci->i_shared_gen;
spin_unlock(&ci->i_ceph_lock);
err = __dcache_readdir(file, ctx, shared_gen);
if (err != -EAGAIN)
return err;
frag = fpos_frag(ctx->pos);
off = fpos_off(ctx->pos);
} else {
spin_unlock(&ci->i_ceph_lock);
}
/* 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;
}
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);
err = ceph_alloc_readdir_reply_buffer(req, inode);
if (err) {
ceph_mdsc_put_request(req);
return err;
}
/* 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;
if (fi->last_name) {
req->r_path2 = kstrdup(fi->last_name, GFP_KERNEL);
if (!req->r_path2) {
ceph_mdsc_put_request(req);
return -ENOMEM;
}
}
req->r_dir_release_cnt = fi->dir_release_count;
req->r_dir_ordered_cnt = fi->dir_ordered_count;
req->r_readdir_cache_idx = fi->readdir_cache_idx;
req->r_readdir_offset = fi->next_offset;
req->r_args.readdir.frag = cpu_to_le32(frag);
req->r_inode = inode;
ihold(inode);
req->r_dentry = dget(file->f_path.dentry);
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);
/* note next offset and last dentry name */
rinfo = &req->r_reply_info;
if (le32_to_cpu(rinfo->dir_dir->frag) != frag) {
frag = le32_to_cpu(rinfo->dir_dir->frag);
off = req->r_readdir_offset;
fi->next_offset = off;
}
fi->frag = frag;
fi->offset = fi->next_offset;
fi->last_readdir = req;
if (req->r_did_prepopulate) {
fi->readdir_cache_idx = req->r_readdir_cache_idx;
if (fi->readdir_cache_idx < 0) {
/* preclude from marking dir ordered */
fi->dir_ordered_count = 0;
} else if (ceph_frag_is_leftmost(frag) && off == 2) {
/* note dir version at start of readdir so
* we can tell if any dentries get dropped */
fi->dir_release_count = req->r_dir_release_cnt;
fi->dir_ordered_count = req->r_dir_ordered_cnt;
}
} else {
dout("readdir !did_prepopulate");
/* disable readdir cache */
fi->readdir_cache_idx = -1;
/* preclude from marking dir complete */
fi->dir_release_count = 0;
}
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 {
err = note_last_dentry(fi,
rinfo->dir_dname[rinfo->dir_nr-1],
rinfo->dir_dname_len[rinfo->dir_nr-1],
fi->next_offset + rinfo->dir_nr);
if (err)
return err;
}
}
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);
ctx->pos = ceph_make_fpos(frag, off);
while (off >= fi->offset && off - fi->offset < rinfo->dir_nr) {
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, ctx->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 (!dir_emit(ctx,
rinfo->dir_dname[off - fi->offset],
rinfo->dir_dname_len[off - fi->offset],
ceph_translate_ino(inode->i_sb, ino), ftype)) {
dout("filldir stopping us...\n");
return 0;
}
off++;
ctx->pos++;
}
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;
ctx->pos = ceph_make_fpos(frag, off);
dout("readdir next frag is %x\n", frag);
goto more;
}
fi->flags |= CEPH_F_ATEND;
/*
* 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.
*/
if (atomic64_read(&ci->i_release_count) == fi->dir_release_count) {
spin_lock(&ci->i_ceph_lock);
if (fi->dir_ordered_count == atomic64_read(&ci->i_ordered_count)) {
dout(" marking %p complete and ordered\n", inode);
/* use i_size to track number of entries in
* readdir cache */
BUG_ON(fi->readdir_cache_idx < 0);
i_size_write(inode, fi->readdir_cache_idx *
sizeof(struct dentry*));
} else {
dout(" marking %p complete\n", inode);
}
__ceph_dir_set_complete(ci, fi->dir_release_count,
fi->dir_ordered_count);
spin_unlock(&ci->i_ceph_lock);
}
dout("readdir %p file %p done.\n", inode, file);
return 0;
}
static void reset_readdir(struct ceph_file_info *fi, unsigned frag)
{
if (fi->last_readdir) {
ceph_mdsc_put_request(fi->last_readdir);
fi->last_readdir = NULL;
}
kfree(fi->last_name);
fi->last_name = NULL;
fi->dir_release_count = 0;
fi->readdir_cache_idx = -1;
if (ceph_frag_is_leftmost(frag))
fi->next_offset = 2; /* compensate for . and .. */
else
fi->next_offset = 0;
fi->flags &= ~CEPH_F_ATEND;
}
static loff_t ceph_dir_llseek(struct file *file, loff_t offset, int whence)
{
struct ceph_file_info *fi = file->private_data;
struct inode *inode = file->f_mapping->host;
loff_t old_offset = ceph_make_fpos(fi->frag, fi->next_offset);
loff_t retval;
inode_lock(inode);
retval = -EINVAL;
switch (whence) {
case SEEK_CUR:
offset += file->f_pos;
case SEEK_SET:
break;
case SEEK_END:
retval = -EOPNOTSUPP;
default:
goto out;
}
if (offset >= 0) {
if (offset != file->f_pos) {
file->f_pos = offset;
file->f_version = 0;
fi->flags &= ~CEPH_F_ATEND;
}
retval = offset;
if (offset == 0 ||
fpos_frag(offset) != fi->frag ||
fpos_off(offset) < fi->offset) {
/* discard buffered readdir content on seekdir(0), or
* seek to new frag, or seek prior to current chunk */
dout("dir_llseek dropping %p content\n", file);
reset_readdir(fi, fpos_frag(offset));
} else if (fpos_cmp(offset, old_offset) > 0) {
/* reset dir_release_count if we did a forward seek */
fi->dir_release_count = 0;
fi->readdir_cache_idx = -1;
}
}
out:
inode_unlock(inode);
return retval;
}
/*
* Handle lookups for the hidden .snap directory.
*/
int ceph_handle_snapdir(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 = d_inode(dentry->d_parent); /* we hold i_mutex */
/* .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 '%pd', linking to snapdir %p\n",
dentry, dentry, inode);
BUG_ON(!d_unhashed(dentry));
d_add(dentry, inode);
err = 0;
}
return err;
}
/*
* Figure out final 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)
{
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, d_inode(dentry));
if (d_really_is_positive(dentry)) {
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,
unsigned int flags)
{
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 mask;
int err;
dout("lookup %p dentry %p '%pd'\n",
dir, dentry, dentry);
if (dentry->d_name.len > NAME_MAX)
return ERR_PTR(-ENAMETOOLONG);
err = ceph_init_dentry(dentry);
if (err < 0)
return ERR_PTR(err);
/* can we conclude ENOENT locally? */
if (d_really_is_negative(dentry)) {
struct ceph_inode_info *ci = ceph_inode(dir);
struct ceph_dentry_info *di = ceph_dentry(dentry);
spin_lock(&ci->i_ceph_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) &&
ceph_test_mount_opt(fsc, DCACHE) &&
__ceph_dir_is_complete(ci) &&
(__ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1))) {
spin_unlock(&ci->i_ceph_lock);
dout(" dir %p complete, -ENOENT\n", dir);
d_add(dentry, NULL);
di->lease_shared_gen = ci->i_shared_gen;
return NULL;
}
spin_unlock(&ci->i_ceph_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;
mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;
if (ceph_security_xattr_wanted(dir))
mask |= CEPH_CAP_XATTR_SHARED;
req->r_args.getattr.mask = cpu_to_le32(mask);
req->r_locked_dir = dir;
err = ceph_mdsc_do_request(mdsc, NULL, req);
err = ceph_handle_snapdir(req, dentry, err);
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, 0);
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). To not
* confuse VFS (especially when inode is a directory),
* we don't link our dentry to that inode, return an
* error instead.
*
* This event should be rare and it happens only when
* we talk to old MDS. Recent MDS does not send traceless
* reply for request that creates new inode.
*/
d_drop(result);
return -ESTALE;
}
return PTR_ERR(result);
}
static int ceph_mknod(struct inode *dir, struct dentry *dentry,
umode_t 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;
struct ceph_acls_info acls = {};
int err;
if (ceph_snap(dir) != CEPH_NOSNAP)
return -EROFS;
err = ceph_pre_init_acls(dir, &mode, &acls);
if (err < 0)
return err;
dout("mknod in dir %p dentry %p mode 0%ho rdev %d\n",
dir, dentry, mode, rdev);
req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_MKNOD, 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.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;
if (acls.pagelist) {
req->r_pagelist = acls.pagelist;
acls.pagelist = NULL;
}
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)
ceph_init_inode_acls(d_inode(dentry), &acls);
else
d_drop(dentry);
ceph_release_acls_info(&acls);
return err;
}
static int ceph_create(struct inode *dir, struct dentry *dentry, umode_t mode,
bool excl)
{
return ceph_mknod(dir, dentry, mode, 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)) {
err = PTR_ERR(req);
goto out;
}
req->r_path2 = kstrdup(dest, GFP_KERNEL);
if (!req->r_path2) {
err = -ENOMEM;
ceph_mdsc_put_request(req);
goto out;
}
req->r_locked_dir = dir;
req->r_dentry = dget(dentry);
req->r_num_caps = 2;
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)
d_drop(dentry);
return err;
}
static int ceph_mkdir(struct inode *dir, struct dentry *dentry, umode_t 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;
struct ceph_acls_info acls = {};
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 '%pd' dn %p\n", dir,
dentry, dentry);
} else if (ceph_snap(dir) == CEPH_NOSNAP) {
dout("mkdir dir %p dn %p mode 0%ho\n", dir, dentry, mode);
op = CEPH_MDS_OP_MKDIR;
} else {
goto out;
}
mode |= S_IFDIR;
err = ceph_pre_init_acls(dir, &mode, &acls);
if (err < 0)
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;
if (acls.pagelist) {
req->r_pagelist = acls.pagelist;
acls.pagelist = NULL;
}
err = ceph_mdsc_do_request(mdsc, dir, req);
if (!err &&
!req->r_reply_info.head->is_target &&
!req->r_reply_info.head->is_dentry)
err = ceph_handle_notrace_create(dir, dentry);
ceph_mdsc_put_request(req);
out:
if (!err)
ceph_init_inode_acls(d_inode(dentry), &acls);
else
d_drop(dentry);
ceph_release_acls_info(&acls);
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);
req->r_locked_dir = dir;
req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
/* release LINK_SHARED on source inode (mds will lock it) */
req->r_old_inode_drop = CEPH_CAP_LINK_SHARED;
err = ceph_mdsc_do_request(mdsc, dir, req);
if (err) {
d_drop(dentry);
} else if (!req->r_reply_info.head->is_dentry) {
ihold(d_inode(old_dentry));
d_instantiate(dentry, d_inode(old_dentry));
}
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(&ci->i_ceph_lock);
if (inode->i_nlink == 1) {
drop |= ~(__ceph_caps_wanted(ci) | CEPH_CAP_PIN);
ci->i_ceph_flags |= CEPH_I_NODELAY;
}
spin_unlock(&ci->i_ceph_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 = d_inode(dentry);
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 '%pd' dn %p\n", dir, dentry, 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 = d_is_dir(dentry) ?
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 op = CEPH_MDS_OP_RENAME;
int err;
if (ceph_snap(old_dir) != ceph_snap(new_dir))
return -EXDEV;
if (ceph_snap(old_dir) != CEPH_NOSNAP) {
if (old_dir == new_dir && ceph_snap(old_dir) == CEPH_SNAPDIR)
op = CEPH_MDS_OP_RENAMESNAP;
else
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, op, USE_AUTH_MDS);
if (IS_ERR(req))
return PTR_ERR(req);
ihold(old_dir);
req->r_dentry = dget(new_dentry);
req->r_num_caps = 2;
req->r_old_dentry = dget(old_dentry);
req->r_old_dentry_dir = old_dir;
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 (d_really_is_positive(new_dentry))
req->r_inode_drop = drop_caps_for_unlink(d_inode(new_dentry));
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 sibling dentries' offsets */
ceph_dir_clear_complete(old_dir);
ceph_dir_clear_complete(new_dir);
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->lease_session) {
s = di->lease_session;
spin_lock(&s->s_gen_ttl_lock);
gen = s->s_cap_gen;
ttl = s->s_cap_ttl;
spin_unlock(&s->s_gen_ttl_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 = d_inode(dentry->d_parent);
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(&ci->i_ceph_lock);
if (ci->i_shared_gen == di->lease_shared_gen)
valid = __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1);
spin_unlock(&ci->i_ceph_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, unsigned int flags)
{
int valid = 0;
struct dentry *parent;
struct inode *dir;
if (flags & LOOKUP_RCU)
return -ECHILD;
dout("d_revalidate %p '%pd' inode %p offset %lld\n", dentry,
dentry, d_inode(dentry), ceph_dentry(dentry)->offset);
parent = dget_parent(dentry);
dir = d_inode(parent);
/* always trust cached snapped dentries, snapdir dentry */
if (ceph_snap(dir) != CEPH_NOSNAP) {
dout("d_revalidate %p '%pd' inode %p is SNAPPED\n", dentry,
dentry, d_inode(dentry));
valid = 1;
} else if (d_really_is_positive(dentry) &&
ceph_snap(d_inode(dentry)) == CEPH_SNAPDIR) {
valid = 1;
} else if (dentry_lease_is_valid(dentry) ||
dir_lease_is_valid(dir, dentry)) {
if (d_really_is_positive(dentry))
valid = ceph_is_any_caps(d_inode(dentry));
else
valid = 1;
}
if (!valid) {
struct ceph_mds_client *mdsc =
ceph_sb_to_client(dir->i_sb)->mdsc;
struct ceph_mds_request *req;
int op, mask, err;
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)) {
req->r_dentry = dget(dentry);
req->r_num_caps = 2;
mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;
if (ceph_security_xattr_wanted(dir))
mask |= CEPH_CAP_XATTR_SHARED;
req->r_args.getattr.mask = mask;
req->r_locked_dir = dir;
err = ceph_mdsc_do_request(mdsc, NULL, req);
if (err == 0 || err == -ENOENT) {
if (dentry == req->r_dentry) {
valid = !d_unhashed(dentry);
} else {
d_invalidate(req->r_dentry);
err = -EAGAIN;
}
}
ceph_mdsc_put_request(req);
dout("d_revalidate %p lookup result=%d\n",
dentry, err);
}
}
dout("d_revalidate %p %s\n", dentry, valid ? "valid" : "invalid");
if (valid) {
ceph_dentry_lru_touch(dentry);
} else {
ceph_dir_clear_complete(dir);
}
dput(parent);
return valid;
}
/*
* 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);
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,
unsigned int flags)
{
/*
* Eventually, we'll want to revalidate snapped metadata
* too... probably...
*/
return 1;
}
/*
* When the VFS prunes a dentry from the cache, we need to clear the
* complete flag on the parent directory.
*
* Called under dentry->d_lock.
*/
static void ceph_d_prune(struct dentry *dentry)
{
dout("ceph_d_prune %p\n", dentry);
/* do we have a valid parent? */
if (IS_ROOT(dentry))
return;
/* if we are not hashed, we don't affect dir's completeness */
if (d_unhashed(dentry))
return;
/*
* we hold d_lock, so d_parent is stable, and d_fsdata is never
* cleared until d_release
*/
ceph_dir_clear_complete(d_inode(dentry->d_parent));
}
/*
* 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_inode(file);
struct ceph_inode_info *ci = ceph_inode(inode);
int left;
const int bufsize = 1024;
if (!ceph_test_mount_opt(ceph_sb_to_client(inode->i_sb), DIRSTAT))
return -EISDIR;
if (!cf->dir_info) {
cf->dir_info = kmalloc(bufsize, GFP_KERNEL);
if (!cf->dir_info)
return -ENOMEM;
cf->dir_info_len =
snprintf(cf->dir_info, bufsize,
"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;
}
/*
* 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 '%pd'\n", di, dn, dn);
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 '%pd' (offset %lld)\n", di, dn, dn,
di->offset);
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 '%pd'\n", di, dn, dn);
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 inode *dir, struct dentry *dn)
{
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,
.iterate = ceph_readdir,
.llseek = ceph_dir_llseek,
.open = ceph_open,
.release = ceph_release,
.unlocked_ioctl = ceph_ioctl,
.fsync = ceph_fsync,
};
const struct file_operations ceph_snapdir_fops = {
.iterate = ceph_readdir,
.llseek = ceph_dir_llseek,
.open = ceph_open,
.release = ceph_release,
};
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,
.get_acl = ceph_get_acl,
.set_acl = ceph_set_acl,
.mknod = ceph_mknod,
.symlink = ceph_symlink,
.mkdir = ceph_mkdir,
.link = ceph_link,
.unlink = ceph_unlink,
.rmdir = ceph_unlink,
.rename = ceph_rename,
.create = ceph_create,
.atomic_open = ceph_atomic_open,
};
const struct inode_operations ceph_snapdir_iops = {
.lookup = ceph_lookup,
.permission = ceph_permission,
.getattr = ceph_getattr,
.mkdir = ceph_mkdir,
.rmdir = ceph_unlink,
.rename = ceph_rename,
};
const struct dentry_operations ceph_dentry_ops = {
.d_revalidate = ceph_d_revalidate,
.d_release = ceph_d_release,
.d_prune = ceph_d_prune,
};
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,
.d_prune = ceph_d_prune,
};
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