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>
---
V7:
- Fix the xfstest generic/006 crash bug about the rde->dentry == NULL.
V6:
- Remove CEPH_ENCRYPTED_LONG_SNAP_NAME_MAX macro and use the NAME_MAX
instead, since we are limiting the max length of snapshot name to
240, which is NAME_MAX - 2 * sizeof('_') - sizeof(<inode#>).
V5:
- fix typo of CEPH_ENCRYPTED_LONG_SNAP_NAME_MAX macro
- release the rde->dentry in destroy_reply_info
fs/ceph/dir.c | 56 ++++++++++++++++++++------------------------
fs/ceph/inode.c | 7 ++++++
fs/ceph/mds_client.c | 1 +
fs/ceph/mds_client.h | 1 +
4 files changed, 34 insertions(+), 31 deletions(-)
diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
index 6df2a91af236..2397c34e9173 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)
@@ -369,14 +368,6 @@ 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? */
@@ -528,31 +519,36 @@ static int ceph_readdir(struct file *file, struct dir_context *ctx)
}
}
}
+
+ dentry_name = kmalloc(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);
+
+ 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)) {
/*
@@ -566,8 +562,6 @@ static int ceph_readdir(struct file *file, struct dir_context *ctx)
goto out;
}
- /* Reset the lengths to their original allocated vals */
- oname.len = olen;
ctx->pos++;
}
@@ -625,8 +619,8 @@ 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 b573a0f33450..19e5275eae1c 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -1909,6 +1909,7 @@ 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);
@@ -1969,6 +1970,12 @@ 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);
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 8d704ddd7291..9e0a51ef1dfa 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -733,6 +733,7 @@ static void destroy_reply_info(struct ceph_mds_reply_info_parsed *info)
kfree(rde->inode.fscrypt_auth);
kfree(rde->inode.fscrypt_file);
+ dput(rde->dentry);
}
free_pages((unsigned long)info->dir_entries, get_order(info->dir_buf_size));
}
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
