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-rw-r--r--fs/ceph/dir.c1541
1 files changed, 1541 insertions, 0 deletions
diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
new file mode 100644
index 000000000..7f3f64ba4
--- /dev/null
+++ b/fs/ceph/dir.c
@@ -0,0 +1,1541 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/ceph/ceph_debug.h>
+
+#include <linux/spinlock.h>
+#include <linux/namei.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+#include <linux/xattr.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.
+ */
+static int ceph_d_init(struct dentry *dentry)
+{
+ struct ceph_dentry_info *di;
+
+ di = kmem_cache_zalloc(ceph_dentry_cachep, GFP_KERNEL);
+ if (!di)
+ return -ENOMEM; /* oh well */
+
+ di->dentry = dentry;
+ di->lease_session = NULL;
+ di->time = jiffies;
+ dentry->d_fsdata = di;
+ ceph_dentry_lru_add(dentry);
+ return 0;
+}
+
+/*
+ * for f_pos for readdir:
+ * - hash order:
+ * (0xff << 52) | ((24 bits hash) << 28) |
+ * (the nth entry has hash collision);
+ * - frag+name order;
+ * ((frag value) << 28) | (the nth entry in frag);
+ */
+#define OFFSET_BITS 28
+#define OFFSET_MASK ((1 << OFFSET_BITS) - 1)
+#define HASH_ORDER (0xffull << (OFFSET_BITS + 24))
+loff_t ceph_make_fpos(unsigned high, unsigned off, bool hash_order)
+{
+ loff_t fpos = ((loff_t)high << 28) | (loff_t)off;
+ if (hash_order)
+ fpos |= HASH_ORDER;
+ return fpos;
+}
+
+static bool is_hash_order(loff_t p)
+{
+ return (p & HASH_ORDER) == HASH_ORDER;
+}
+
+static unsigned fpos_frag(loff_t p)
+{
+ return p >> OFFSET_BITS;
+}
+
+static unsigned fpos_hash(loff_t p)
+{
+ return ceph_frag_value(fpos_frag(p));
+}
+
+static unsigned fpos_off(loff_t p)
+{
+ return p & OFFSET_MASK;
+}
+
+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_dir_file_info *dfi, const char *name,
+ int len, unsigned next_offset)
+{
+ char *buf = kmalloc(len+1, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+ kfree(dfi->last_name);
+ dfi->last_name = buf;
+ memcpy(dfi->last_name, name, len);
+ dfi->last_name[len] = 0;
+ dfi->next_offset = next_offset;
+ dout("note_last_dentry '%s'\n", dfi->last_name);
+ return 0;
+}
+
+
+static struct dentry *
+__dcache_find_get_entry(struct dentry *parent, u64 idx,
+ struct ceph_readdir_cache_control *cache_ctl)
+{
+ struct inode *dir = d_inode(parent);
+ struct dentry *dentry;
+ unsigned idx_mask = (PAGE_SIZE / sizeof(struct dentry *)) - 1;
+ loff_t ptr_pos = idx * sizeof(struct dentry *);
+ pgoff_t ptr_pgoff = ptr_pos >> PAGE_SHIFT;
+
+ if (ptr_pos >= i_size_read(dir))
+ return NULL;
+
+ if (!cache_ctl->page || ptr_pgoff != page_index(cache_ctl->page)) {
+ ceph_readdir_cache_release(cache_ctl);
+ cache_ctl->page = find_lock_page(&dir->i_data, ptr_pgoff);
+ if (!cache_ctl->page) {
+ dout(" page %lu not found\n", ptr_pgoff);
+ return ERR_PTR(-EAGAIN);
+ }
+ /* 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);
+ }
+
+ cache_ctl->index = idx & idx_mask;
+
+ 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];
+ else
+ dentry = NULL;
+ spin_unlock(&parent->d_lock);
+ if (dentry && !lockref_get_not_dead(&dentry->d_lockref))
+ dentry = NULL;
+ rcu_read_unlock();
+ return dentry ? : ERR_PTR(-EAGAIN);
+}
+
+/*
+ * 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,
+ int shared_gen)
+{
+ struct ceph_dir_file_info *dfi = 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;
+ struct ceph_readdir_cache_control cache_ctl = {};
+ u64 idx = 0;
+ int err = 0;
+
+ dout("__dcache_readdir %p v%u at %llx\n", dir, (unsigned)shared_gen, ctx->pos);
+
+ /* search start position */
+ if (ctx->pos > 2) {
+ u64 count = div_u64(i_size_read(dir), sizeof(struct dentry *));
+ while (count > 0) {
+ u64 step = count >> 1;
+ dentry = __dcache_find_get_entry(parent, idx + step,
+ &cache_ctl);
+ if (!dentry) {
+ /* use linar search */
+ idx = 0;
+ break;
+ }
+ if (IS_ERR(dentry)) {
+ err = PTR_ERR(dentry);
+ goto out;
+ }
+ di = ceph_dentry(dentry);
+ spin_lock(&dentry->d_lock);
+ if (fpos_cmp(di->offset, ctx->pos) < 0) {
+ idx += step + 1;
+ count -= step + 1;
+ } else {
+ count = step;
+ }
+ spin_unlock(&dentry->d_lock);
+ dput(dentry);
+ }
+
+ dout("__dcache_readdir %p cache idx %llu\n", dir, idx);
+ }
+
+
+ for (;;) {
+ bool emit_dentry = false;
+ dentry = __dcache_find_get_entry(parent, idx++, &cache_ctl);
+ if (!dentry) {
+ dfi->file_info.flags |= CEPH_F_ATEND;
+ err = 0;
+ break;
+ }
+ if (IS_ERR(dentry)) {
+ err = PTR_ERR(dentry);
+ goto out;
+ }
+
+ spin_lock(&dentry->d_lock);
+ di = ceph_dentry(dentry);
+ if (d_unhashed(dentry) ||
+ d_really_is_negative(dentry) ||
+ di->lease_shared_gen != shared_gen) {
+ spin_unlock(&dentry->d_lock);
+ dput(dentry);
+ err = -EAGAIN;
+ goto out;
+ }
+ if (fpos_cmp(ctx->pos, di->offset) <= 0) {
+ emit_dentry = true;
+ }
+ spin_unlock(&dentry->d_lock);
+
+ if (emit_dentry) {
+ dout(" %llx dentry %p %pd %p\n", di->offset,
+ 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);
+ }
+ }
+out:
+ ceph_readdir_cache_release(&cache_ctl);
+ if (last) {
+ int ret;
+ di = ceph_dentry(last);
+ ret = note_last_dentry(dfi, last->d_name.name, last->d_name.len,
+ fpos_off(di->offset) + 1);
+ if (ret < 0)
+ err = ret;
+ dput(last);
+ /* last_name no longer match cache index */
+ if (dfi->readdir_cache_idx >= 0) {
+ dfi->readdir_cache_idx = -1;
+ dfi->dir_release_count = 0;
+ }
+ }
+ return err;
+}
+
+static bool need_send_readdir(struct ceph_dir_file_info *dfi, loff_t pos)
+{
+ if (!dfi->last_readdir)
+ return true;
+ if (is_hash_order(pos))
+ return !ceph_frag_contains_value(dfi->frag, fpos_hash(pos));
+ else
+ return dfi->frag != fpos_frag(pos);
+}
+
+static int ceph_readdir(struct file *file, struct dir_context *ctx)
+{
+ struct ceph_dir_file_info *dfi = 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;
+ int i;
+ int err;
+ unsigned frag = -1;
+ struct ceph_mds_reply_info_parsed *rinfo;
+
+ dout("readdir %p file %p pos %llx\n", inode, file, ctx->pos);
+ if (dfi->file_info.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;
+ }
+ 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;
+ }
+
+ /* 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)) {
+ int shared_gen = atomic_read(&ci->i_shared_gen);
+ spin_unlock(&ci->i_ceph_lock);
+ err = __dcache_readdir(file, ctx, shared_gen);
+ if (err != -EAGAIN)
+ return err;
+ } else {
+ spin_unlock(&ci->i_ceph_lock);
+ }
+
+ /* proceed with a normal readdir */
+more:
+ /* do we have the correct frag content buffered? */
+ if (need_send_readdir(dfi, ctx->pos)) {
+ 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 (dfi->last_readdir) {
+ ceph_mdsc_put_request(dfi->last_readdir);
+ dfi->last_readdir = NULL;
+ }
+
+ if (is_hash_order(ctx->pos)) {
+ /* fragtree isn't always accurate. choose frag
+ * based on previous reply when possible. */
+ if (frag == (unsigned)-1)
+ frag = ceph_choose_frag(ci, fpos_hash(ctx->pos),
+ NULL, NULL);
+ } else {
+ frag = fpos_frag(ctx->pos);
+ }
+
+ dout("readdir fetching %llx.%llx frag %x offset '%s'\n",
+ ceph_vinop(inode), frag, dfi->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;
+ if (op == CEPH_MDS_OP_READDIR) {
+ req->r_direct_hash = ceph_frag_value(frag);
+ __set_bit(CEPH_MDS_R_DIRECT_IS_HASH, &req->r_req_flags);
+ req->r_inode_drop = CEPH_CAP_FILE_EXCL;
+ }
+ if (dfi->last_name) {
+ req->r_path2 = kstrdup(dfi->last_name, GFP_KERNEL);
+ if (!req->r_path2) {
+ ceph_mdsc_put_request(req);
+ return -ENOMEM;
+ }
+ } else if (is_hash_order(ctx->pos)) {
+ req->r_args.readdir.offset_hash =
+ cpu_to_le32(fpos_hash(ctx->pos));
+ }
+
+ req->r_dir_release_cnt = dfi->dir_release_count;
+ req->r_dir_ordered_cnt = dfi->dir_ordered_count;
+ req->r_readdir_cache_idx = dfi->readdir_cache_idx;
+ req->r_readdir_offset = dfi->next_offset;
+ req->r_args.readdir.frag = cpu_to_le32(frag);
+ req->r_args.readdir.flags =
+ cpu_to_le16(CEPH_READDIR_REPLY_BITFLAGS);
+
+ 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, hash_order=%d\n",
+ err, frag,
+ (int)req->r_reply_info.dir_end,
+ (int)req->r_reply_info.dir_complete,
+ (int)req->r_reply_info.hash_order);
+
+ rinfo = &req->r_reply_info;
+ if (le32_to_cpu(rinfo->dir_dir->frag) != frag) {
+ frag = le32_to_cpu(rinfo->dir_dir->frag);
+ if (!rinfo->hash_order) {
+ dfi->next_offset = req->r_readdir_offset;
+ /* adjust ctx->pos to beginning of frag */
+ ctx->pos = ceph_make_fpos(frag,
+ dfi->next_offset,
+ false);
+ }
+ }
+
+ dfi->frag = frag;
+ dfi->last_readdir = req;
+
+ if (test_bit(CEPH_MDS_R_DID_PREPOPULATE, &req->r_req_flags)) {
+ dfi->readdir_cache_idx = req->r_readdir_cache_idx;
+ if (dfi->readdir_cache_idx < 0) {
+ /* preclude from marking dir ordered */
+ dfi->dir_ordered_count = 0;
+ } else if (ceph_frag_is_leftmost(frag) &&
+ dfi->next_offset == 2) {
+ /* note dir version at start of readdir so
+ * we can tell if any dentries get dropped */
+ dfi->dir_release_count = req->r_dir_release_cnt;
+ dfi->dir_ordered_count = req->r_dir_ordered_cnt;
+ }
+ } else {
+ dout("readdir !did_prepopulate\n");
+ /* disable readdir cache */
+ dfi->readdir_cache_idx = -1;
+ /* preclude from marking dir complete */
+ dfi->dir_release_count = 0;
+ }
+
+ /* note next offset and last dentry name */
+ if (rinfo->dir_nr > 0) {
+ struct ceph_mds_reply_dir_entry *rde =
+ rinfo->dir_entries + (rinfo->dir_nr-1);
+ unsigned next_offset = req->r_reply_info.dir_end ?
+ 2 : (fpos_off(rde->offset) + 1);
+ err = note_last_dentry(dfi, rde->name, rde->name_len,
+ next_offset);
+ if (err)
+ return err;
+ } else if (req->r_reply_info.dir_end) {
+ dfi->next_offset = 2;
+ /* keep last name */
+ }
+ }
+
+ rinfo = &dfi->last_readdir->r_reply_info;
+ dout("readdir frag %x num %d pos %llx chunk first %llx\n",
+ dfi->frag, rinfo->dir_nr, ctx->pos,
+ rinfo->dir_nr ? rinfo->dir_entries[0].offset : 0LL);
+
+ i = 0;
+ /* search start position */
+ if (rinfo->dir_nr > 0) {
+ int step, nr = rinfo->dir_nr;
+ while (nr > 0) {
+ step = nr >> 1;
+ if (rinfo->dir_entries[i + step].offset < ctx->pos) {
+ i += step + 1;
+ nr -= step + 1;
+ } else {
+ nr = step;
+ }
+ }
+ }
+ for (; i < rinfo->dir_nr; i++) {
+ struct ceph_mds_reply_dir_entry *rde = rinfo->dir_entries + i;
+ struct ceph_vino vino;
+ ino_t ino;
+ u32 ftype;
+
+ BUG_ON(rde->offset < ctx->pos);
+
+ ctx->pos = rde->offset;
+ dout("readdir (%d/%d) -> %llx '%.*s' %p\n",
+ i, rinfo->dir_nr, ctx->pos,
+ rde->name_len, rde->name, &rde->inode.in);
+
+ BUG_ON(!rde->inode.in);
+ ftype = le32_to_cpu(rde->inode.in->mode) >> 12;
+ vino.ino = le64_to_cpu(rde->inode.in->ino);
+ vino.snap = le64_to_cpu(rde->inode.in->snapid);
+ ino = ceph_vino_to_ino(vino);
+
+ if (!dir_emit(ctx, rde->name, rde->name_len,
+ ceph_translate_ino(inode->i_sb, ino), ftype)) {
+ dout("filldir stopping us...\n");
+ return 0;
+ }
+ ctx->pos++;
+ }
+
+ ceph_mdsc_put_request(dfi->last_readdir);
+ dfi->last_readdir = NULL;
+
+ if (dfi->next_offset > 2) {
+ frag = dfi->frag;
+ goto more;
+ }
+
+ /* more frags? */
+ if (!ceph_frag_is_rightmost(dfi->frag)) {
+ frag = ceph_frag_next(dfi->frag);
+ if (is_hash_order(ctx->pos)) {
+ loff_t new_pos = ceph_make_fpos(ceph_frag_value(frag),
+ dfi->next_offset, true);
+ if (new_pos > ctx->pos)
+ ctx->pos = new_pos;
+ /* keep last_name */
+ } else {
+ ctx->pos = ceph_make_fpos(frag, dfi->next_offset,
+ false);
+ kfree(dfi->last_name);
+ dfi->last_name = NULL;
+ }
+ dout("readdir next frag is %x\n", frag);
+ goto more;
+ }
+ dfi->file_info.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) ==
+ dfi->dir_release_count) {
+ spin_lock(&ci->i_ceph_lock);
+ if (dfi->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(dfi->readdir_cache_idx < 0);
+ i_size_write(inode, dfi->readdir_cache_idx *
+ sizeof(struct dentry*));
+ } else {
+ dout(" marking %p complete\n", inode);
+ }
+ __ceph_dir_set_complete(ci, dfi->dir_release_count,
+ dfi->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_dir_file_info *dfi)
+{
+ if (dfi->last_readdir) {
+ ceph_mdsc_put_request(dfi->last_readdir);
+ dfi->last_readdir = NULL;
+ }
+ kfree(dfi->last_name);
+ dfi->last_name = NULL;
+ dfi->dir_release_count = 0;
+ dfi->readdir_cache_idx = -1;
+ dfi->next_offset = 2; /* compensate for . and .. */
+ dfi->file_info.flags &= ~CEPH_F_ATEND;
+}
+
+/*
+ * discard buffered readdir content on seekdir(0), or seek to new frag,
+ * or seek prior to current chunk
+ */
+static bool need_reset_readdir(struct ceph_dir_file_info *dfi, loff_t new_pos)
+{
+ struct ceph_mds_reply_info_parsed *rinfo;
+ loff_t chunk_offset;
+ if (new_pos == 0)
+ return true;
+ if (is_hash_order(new_pos)) {
+ /* no need to reset last_name for a forward seek when
+ * dentries are sotred in hash order */
+ } else if (dfi->frag != fpos_frag(new_pos)) {
+ return true;
+ }
+ rinfo = dfi->last_readdir ? &dfi->last_readdir->r_reply_info : NULL;
+ if (!rinfo || !rinfo->dir_nr)
+ return true;
+ chunk_offset = rinfo->dir_entries[0].offset;
+ return new_pos < chunk_offset ||
+ is_hash_order(new_pos) != is_hash_order(chunk_offset);
+}
+
+static loff_t ceph_dir_llseek(struct file *file, loff_t offset, int whence)
+{
+ struct ceph_dir_file_info *dfi = file->private_data;
+ struct inode *inode = file->f_mapping->host;
+ 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 (need_reset_readdir(dfi, offset)) {
+ dout("dir_llseek dropping %p content\n", file);
+ reset_readdir(dfi);
+ } else if (is_hash_order(offset) && offset > file->f_pos) {
+ /* for hash offset, we don't know if a forward seek
+ * is within same frag */
+ dfi->dir_release_count = 0;
+ dfi->readdir_cache_idx = -1;
+ }
+
+ if (offset != file->f_pos) {
+ file->f_pos = offset;
+ file->f_version = 0;
+ dfi->file_info.flags &= ~CEPH_F_ATEND;
+ }
+ retval = offset;
+ }
+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 bool 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);
+
+ /* 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 = atomic_read(&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_parent = dir;
+ set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
+ 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;
+
+ if (ceph_quota_is_max_files_exceeded(dir)) {
+ err = -EDQUOT;
+ goto out;
+ }
+
+ err = ceph_pre_init_acls(dir, &mode, &acls);
+ if (err < 0)
+ goto out;
+
+ 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_parent = dir;
+ set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
+ 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 | CEPH_CAP_AUTH_EXCL;
+ 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;
+
+ if (ceph_quota_is_max_files_exceeded(dir)) {
+ err = -EDQUOT;
+ goto out;
+ }
+
+ 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_parent = dir;
+ set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
+ req->r_dentry = dget(dentry);
+ req->r_num_caps = 2;
+ req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL;
+ 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;
+ }
+
+ if (op == CEPH_MDS_OP_MKDIR &&
+ ceph_quota_is_max_files_exceeded(dir)) {
+ err = -EDQUOT;
+ 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_parent = dir;
+ set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
+ req->r_args.mkdir.mode = cpu_to_le32(mode);
+ req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL;
+ 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_parent = dir;
+ set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
+ 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 | CEPH_CAP_LINK_EXCL;
+ 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;
+}
+
+/*
+ * 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_parent = dir;
+ set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
+ req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
+ req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
+ req->r_inode_drop = ceph_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,
+ unsigned int flags)
+{
+ 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 (flags)
+ return -EINVAL;
+
+ 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;
+ }
+ /* don't allow cross-quota renames */
+ if ((old_dir != new_dir) &&
+ (!ceph_quota_is_same_realm(old_dir, new_dir)))
+ return -EXDEV;
+
+ 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_parent = new_dir;
+ set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
+ 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 | CEPH_CAP_LINK_EXCL;
+ if (d_really_is_positive(new_dentry)) {
+ req->r_inode_drop =
+ ceph_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(old_dentry, 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);
+ ceph_dentry(dentry)->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, unsigned int flags,
+ struct inode *dir)
+{
+ struct ceph_dentry_info *di;
+ struct ceph_mds_session *s;
+ int valid = 0;
+ u32 gen;
+ unsigned long ttl;
+ struct ceph_mds_session *session = 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_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, di->time) &&
+ time_before(jiffies, ttl)) {
+ valid = 1;
+ if (di->lease_renew_after &&
+ time_after(jiffies, di->lease_renew_after)) {
+ /*
+ * We should renew. If we're in RCU walk mode
+ * though, we can't do that so just return
+ * -ECHILD.
+ */
+ if (flags & LOOKUP_RCU) {
+ valid = -ECHILD;
+ } else {
+ 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 (atomic_read(&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)atomic_read(&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) {
+ parent = READ_ONCE(dentry->d_parent);
+ dir = d_inode_rcu(parent);
+ if (!dir)
+ return -ECHILD;
+ } else {
+ parent = dget_parent(dentry);
+ dir = d_inode(parent);
+ }
+
+ dout("d_revalidate %p '%pd' inode %p offset %lld\n", dentry,
+ dentry, d_inode(dentry), ceph_dentry(dentry)->offset);
+
+ /* 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 {
+ valid = dentry_lease_is_valid(dentry, flags, dir);
+ if (valid == -ECHILD)
+ return valid;
+ if (valid || 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, err;
+ u32 mask;
+
+ if (flags & LOOKUP_RCU)
+ return -ECHILD;
+
+ 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;
+ req->r_parent = dir;
+
+ 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);
+
+ err = ceph_mdsc_do_request(mdsc, NULL, req);
+ switch (err) {
+ case 0:
+ if (d_really_is_positive(dentry) &&
+ d_inode(dentry) == req->r_target_inode)
+ valid = 1;
+ break;
+ case -ENOENT:
+ if (d_really_is_negative(dentry))
+ valid = 1;
+ /* Fallthrough */
+ default:
+ break;
+ }
+ 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);
+ }
+
+ if (!(flags & LOOKUP_RCU))
+ 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);
+
+ spin_lock(&dentry->d_lock);
+ dentry->d_fsdata = NULL;
+ spin_unlock(&dentry->d_lock);
+
+ if (di->lease_session)
+ ceph_put_mds_session(di->lease_session);
+ kmem_cache_free(ceph_dentry_cachep, di);
+}
+
+/*
+ * 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)
+{
+ struct ceph_inode_info *dir_ci;
+ struct ceph_dentry_info *di;
+
+ dout("ceph_d_prune %pd %p\n", dentry, dentry);
+
+ /* do we have a valid parent? */
+ if (IS_ROOT(dentry))
+ return;
+
+ /* we hold d_lock, so d_parent is stable */
+ dir_ci = ceph_inode(d_inode(dentry->d_parent));
+ if (dir_ci->i_vino.snap == CEPH_SNAPDIR)
+ return;
+
+ /* who calls d_delete() should also disable dcache readdir */
+ if (d_really_is_negative(dentry))
+ return;
+
+ /* d_fsdata does not get cleared until d_release */
+ if (!d_unhashed(dentry)) {
+ __ceph_dir_clear_complete(dir_ci);
+ return;
+ }
+
+ /* Disable dcache readdir just in case that someone called d_drop()
+ * or d_invalidate(), but MDS didn't revoke CEPH_CAP_FILE_SHARED
+ * properly (dcache readdir is still enabled) */
+ di = ceph_dentry(dentry);
+ if (di->offset > 0 &&
+ di->lease_shared_gen == atomic_read(&dir_ci->i_shared_gen))
+ __ceph_dir_clear_ordered(dir_ci);
+}
+
+/*
+ * 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_dir_file_info *dfi = 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 (!dfi->dir_info) {
+ dfi->dir_info = kmalloc(bufsize, GFP_KERNEL);
+ if (!dfi->dir_info)
+ return -ENOMEM;
+ dfi->dir_info_len =
+ snprintf(dfi->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: %10lld.%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,
+ ci->i_rctime.tv_sec,
+ ci->i_rctime.tv_nsec);
+ }
+
+ if (*ppos >= dfi->dir_info_len)
+ return 0;
+ size = min_t(unsigned, size, dfi->dir_info_len-*ppos);
+ left = copy_to_user(buf, dfi->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);
+ unsigned hash;
+
+ switch (dci->i_dir_layout.dl_dir_hash) {
+ case 0: /* for backward compat */
+ case CEPH_STR_HASH_LINUX:
+ return dn->d_name.hash;
+
+ default:
+ spin_lock(&dn->d_lock);
+ hash = ceph_str_hash(dci->i_dir_layout.dl_dir_hash,
+ dn->d_name.name, dn->d_name.len);
+ spin_unlock(&dn->d_lock);
+ return hash;
+ }
+}
+
+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,
+ .lock = ceph_lock,
+ .flock = ceph_flock,
+};
+
+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,
+ .listxattr = ceph_listxattr,
+ .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,
+ .d_init = ceph_d_init,
+};