From: Xiubo Li <xiubli@xxxxxxxxxx>
For the readdir request the dentries will be pasred and dencrypted
in ceph_readdir_prepopulate(). And in ceph_readdir() we could just
get the dentry name from the dentry cache instead of parsing and
dencrypting them again. This could improve performance.
Signed-off-by: Xiubo Li <xiubli@xxxxxxxxxx>
---
fs/ceph/crypto.h | 8 +++++
fs/ceph/dir.c | 74 +++++++++++++++++++++++---------------------
fs/ceph/inode.c | 15 +++++++++
fs/ceph/mds_client.h | 1 +
4 files changed, 63 insertions(+), 35 deletions(-)
diff --git a/fs/ceph/crypto.h b/fs/ceph/crypto.h
index 1e08f8a64ad6..9a00c60b8535 100644
--- a/fs/ceph/crypto.h
+++ b/fs/ceph/crypto.h
@@ -83,6 +83,14 @@ static inline u32 ceph_fscrypt_auth_len(struct ceph_fscrypt_auth *fa)
*/
#define CEPH_NOHASH_NAME_MAX (189 - SHA256_DIGEST_SIZE)
+/*
+ * The encrypted long snap name will be in format of
+ * "_${ENCRYPTED-LONG-SNAP-NAME}_${INODE-NUM}". And will set the max longth
+ * to sizeof('_') + NAME_MAX + sizeof('_') + max of sizeof(${INO}) + extra 7
+ * bytes to align the total size to 8 bytes.
+ */
+#define CEPH_ENCRPTED_LONG_SNAP_NAME_MAX (1 + 255 + 1 + 16 + 7)
+
void ceph_fscrypt_set_ops(struct super_block *sb);
void ceph_fscrypt_free_dummy_policy(struct ceph_fs_client *fsc);
diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
index 4da59810b036..fa3da3b29130 100644
--- a/fs/ceph/dir.c
+++ b/fs/ceph/dir.c
@@ -316,8 +316,7 @@ static int ceph_readdir(struct file *file, struct dir_context *ctx)
int err;
unsigned frag = -1;
struct ceph_mds_reply_info_parsed *rinfo;
- struct fscrypt_str tname = FSTR_INIT(NULL, 0);
- struct fscrypt_str oname = FSTR_INIT(NULL, 0);
+ char *dentry_name = NULL;
dout("readdir %p file %p pos %llx\n", inode, file, ctx->pos);
if (dfi->file_info.flags & CEPH_F_ATEND)
@@ -345,10 +344,6 @@ static int ceph_readdir(struct file *file, struct dir_context *ctx)
ctx->pos = 2;
}
- err = fscrypt_prepare_readdir(inode);
- if (err)
- goto out;
-
spin_lock(&ci->i_ceph_lock);
/* request Fx cap. if have Fx, we don't need to release Fs cap
* for later create/unlink. */
@@ -369,14 +364,6 @@ static int ceph_readdir(struct file *file, struct dir_context *ctx)
spin_unlock(&ci->i_ceph_lock);
}
- err = ceph_fname_alloc_buffer(inode, &tname);
- if (err < 0)
- goto out;
-
- err = ceph_fname_alloc_buffer(inode, &oname);
- if (err < 0)
- goto out;
-
/* proceed with a normal readdir */
more:
/* do we have the correct frag content buffered? */
@@ -528,42 +515,59 @@ static int ceph_readdir(struct file *file, struct dir_context *ctx)
}
}
}
+
+ dentry_name = kmalloc(CEPH_ENCRPTED_LONG_SNAP_NAME_MAX, GFP_KERNEL);
+ if (!dentry_name) {
+ err = -ENOMEM;
+ ceph_mdsc_put_request(dfi->last_readdir);
+ dfi->last_readdir = NULL;
+ goto out;
+ }
+
for (; i < rinfo->dir_nr; i++) {
struct ceph_mds_reply_dir_entry *rde = rinfo->dir_entries + i;
- struct ceph_fname fname = { .dir = inode,
- .name = rde->name,
- .name_len = rde->name_len,
- .ctext = rde->altname,
- .ctext_len = rde->altname_len };
- u32 olen = oname.len;
-
- err = ceph_fname_to_usr(&fname, &tname, &oname, NULL);
- if (err) {
- pr_err("%s unable to decode %.*s, got %d\n", __func__,
- rde->name_len, rde->name, err);
- goto out;
- }
+ struct dentry *dn = rde->dentry;
+ int name_len;
BUG_ON(rde->offset < ctx->pos);
BUG_ON(!rde->inode.in);
+ BUG_ON(!rde->dentry);
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);
- if (!dir_emit(ctx, oname.name, oname.len,
+ spin_lock(&dn->d_lock);
+ memcpy(dentry_name, dn->d_name.name, dn->d_name.len);
+ name_len = dn->d_name.len;
+ spin_unlock(&dn->d_lock);
+
+ dentry_name[name_len] = '\0';
+ dout("readdir (%d/%d) -> %llx '%s' %p\n",
+ i, rinfo->dir_nr, ctx->pos, dentry_name, &rde->inode.in);
+
+ dput(dn);
+ rde->dentry = NULL;
+
+ if (!dir_emit(ctx, dentry_name, name_len,
ceph_present_ino(inode->i_sb, le64_to_cpu(rde->inode.in->ino)),
le32_to_cpu(rde->inode.in->mode) >> 12)) {
dout("filldir stopping us...\n");
+
+ /*
+ * dput the rest dentries. Must do this before
+ * releasing the request.
+ */
+ for (++i; i < rinfo->dir_nr; i++) {
+ rde = rinfo->dir_entries + i;
+ dput(rde->dentry);
+ rde->dentry = NULL;
+ }
+
err = 0;
ceph_mdsc_put_request(dfi->last_readdir);
dfi->last_readdir = NULL;
goto out;
}
- /* Reset the lengths to their original allocated vals */
- oname.len = olen;
ctx->pos++;
}
@@ -621,8 +625,8 @@ static int ceph_readdir(struct file *file, struct dir_context *ctx)
err = 0;
dout("readdir %p file %p done.\n", inode, file);
out:
- ceph_fname_free_buffer(inode, &tname);
- ceph_fname_free_buffer(inode, &oname);
+ if (dentry_name)
+ kfree(dentry_name);
return err;
}
diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index e5a9838981ba..d0719feed792 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -1902,6 +1902,7 @@ int ceph_readdir_prepopulate(struct ceph_mds_request *req,
goto out;
}
+ rde->dentry = NULL;
dname.name = oname.name;
dname.len = oname.len;
dname.hash = full_name_hash(parent, dname.name, dname.len);
@@ -1962,6 +1963,12 @@ int ceph_readdir_prepopulate(struct ceph_mds_request *req,
goto retry_lookup;
}
+ /*
+ * ceph_readdir will use the dentry to get the name
+ * to avoid doing the dencrypt again there.
+ */
+ rde->dentry = dget(dn);
+
/* inode */
if (d_really_is_positive(dn)) {
in = d_inode(dn);
@@ -2024,6 +2031,14 @@ int ceph_readdir_prepopulate(struct ceph_mds_request *req,
dput(dn);
}
out:
+ if (err) {
+ for (; i >= 0; i--) {
+ struct ceph_mds_reply_dir_entry *rde;
+
+ rde = rinfo->dir_entries + i;
+ dput(rde->dentry);
+ }
+ }
if (err == 0 && skipped == 0) {
set_bit(CEPH_MDS_R_DID_PREPOPULATE, &req->r_req_flags);
req->r_readdir_cache_idx = cache_ctl.index;
diff --git a/fs/ceph/mds_client.h b/fs/ceph/mds_client.h
index 0dfe24f94567..663d7754d57d 100644
--- a/fs/ceph/mds_client.h
+++ b/fs/ceph/mds_client.h
@@ -96,6 +96,7 @@ struct ceph_mds_reply_info_in {
};
struct ceph_mds_reply_dir_entry {
+ struct dentry *dentry;
char *name;
u8 *altname;
u32 name_len;
--
2.27.0
