Of the 8 compounding optimizations (to use an existing handle if we
already have it open), I removed 4 of the 8 sections, but merged the
other half. See attached:
I left out mkdir and unlink since in those cases the open is what is
doing the work. For the hardlink case I wanted to verify the
permissions needed (you are checking for a writable handle but the
code doesn't appear to be requesting that when no handle is found) so
I wanted to look at that in more detail (and also the rmdir case -
although that may be one we want to add back).
Even with those changes I see a few examples were we appear to not
reuse the already open handle in e.g. revalidate - so there may be
additional compounding optimizations that we can do.
--
Thanks,
Steve
From 60a648a44bd01e5b7a894c5ef964c7254c159329 Mon Sep 17 00:00:00 2001
From: Shyam Prasad N <sprasad@xxxxxxxxxxxxx>
Date: Fri, 30 Jul 2021 06:43:09 +0000
Subject: [PATCH 1/2] cifs: for compound requests, use open handle if possible
For smb2_compound_op, it is possible to pass a ref to
an already open file. We should be passing it whenever possible.
i.e. if a matching handle is already kept open.
If we don't do that, we will end up breaking leases for files
kept open on the same client.
Signed-off-by: Shyam Prasad N <sprasad@xxxxxxxxxxxxx>
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
---
fs/cifs/smb2inode.c | 22 +++++++++++++++++-----
1 file changed, 17 insertions(+), 5 deletions(-)
diff --git a/fs/cifs/smb2inode.c b/fs/cifs/smb2inode.c
index 8297703492ee..fe5bfa245fa7 100644
--- a/fs/cifs/smb2inode.c
+++ b/fs/cifs/smb2inode.c
@@ -46,6 +46,10 @@ struct cop_vars {
struct smb2_file_link_info link_info;
};
+/*
+ * note: If cfile is passed, the reference to it is dropped here.
+ * So make sure that you do not reuse cfile after return from this func.
+ */
static int
smb2_compound_op(const unsigned int xid, struct cifs_tcon *tcon,
struct cifs_sb_info *cifs_sb, const char *full_path,
@@ -536,10 +540,11 @@ smb2_query_path_info(const unsigned int xid, struct cifs_tcon *tcon,
create_options |= OPEN_REPARSE_POINT;
/* Failed on a symbolic link - query a reparse point info */
+ cifs_get_readable_path(tcon, full_path, &cfile);
rc = smb2_compound_op(xid, tcon, cifs_sb, full_path,
FILE_READ_ATTRIBUTES, FILE_OPEN,
create_options, ACL_NO_MODE,
- smb2_data, SMB2_OP_QUERY_INFO, NULL);
+ smb2_data, SMB2_OP_QUERY_INFO, cfile);
}
if (rc)
goto out;
@@ -587,10 +592,11 @@ smb311_posix_query_path_info(const unsigned int xid, struct cifs_tcon *tcon,
create_options |= OPEN_REPARSE_POINT;
/* Failed on a symbolic link - query a reparse point info */
+ cifs_get_readable_path(tcon, full_path, &cfile);
rc = smb2_compound_op(xid, tcon, cifs_sb, full_path,
FILE_READ_ATTRIBUTES, FILE_OPEN,
create_options, ACL_NO_MODE,
- smb2_data, SMB2_OP_POSIX_QUERY_INFO, NULL);
+ smb2_data, SMB2_OP_POSIX_QUERY_INFO, cfile);
}
if (rc)
goto out;
@@ -707,10 +713,12 @@ smb2_set_path_size(const unsigned int xid, struct cifs_tcon *tcon,
struct cifs_sb_info *cifs_sb, bool set_alloc)
{
__le64 eof = cpu_to_le64(size);
+ struct cifsFileInfo *cfile;
+ cifs_get_writable_path(tcon, full_path, FIND_WR_ANY, &cfile);
return smb2_compound_op(xid, tcon, cifs_sb, full_path,
FILE_WRITE_DATA, FILE_OPEN, 0, ACL_NO_MODE,
- &eof, SMB2_OP_SET_EOF, NULL);
+ &eof, SMB2_OP_SET_EOF, cfile);
}
int
@@ -719,6 +727,8 @@ smb2_set_file_info(struct inode *inode, const char *full_path,
{
struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
struct tcon_link *tlink;
+ struct cifs_tcon *tcon;
+ struct cifsFileInfo *cfile;
int rc;
if ((buf->CreationTime == 0) && (buf->LastAccessTime == 0) &&
@@ -729,10 +739,12 @@ smb2_set_file_info(struct inode *inode, const char *full_path,
tlink = cifs_sb_tlink(cifs_sb);
if (IS_ERR(tlink))
return PTR_ERR(tlink);
+ tcon = tlink_tcon(tlink);
- rc = smb2_compound_op(xid, tlink_tcon(tlink), cifs_sb, full_path,
+ cifs_get_writable_path(tcon, full_path, FIND_WR_ANY, &cfile);
+ rc = smb2_compound_op(xid, tcon, cifs_sb, full_path,
FILE_WRITE_ATTRIBUTES, FILE_OPEN,
- 0, ACL_NO_MODE, buf, SMB2_OP_SET_INFO, NULL);
+ 0, ACL_NO_MODE, buf, SMB2_OP_SET_INFO, cfile);
cifs_put_tlink(tlink);
return rc;
}
--
2.32.0
@@ -608,10 +614,13 @@ smb2_mkdir(const unsigned int xid, struct inode *parent_inode, umode_t mode,
struct cifs_tcon *tcon, const char *name,
struct cifs_sb_info *cifs_sb)
{
+ struct cifsFileInfo *cfile;
+
+ cifs_get_writable_path(tcon, name, FIND_WR_ANY, &cfile);
return smb2_compound_op(xid, tcon, cifs_sb, name,
FILE_WRITE_ATTRIBUTES, FILE_CREATE,
CREATE_NOT_FILE, mode, NULL, SMB2_OP_MKDIR,
- NULL);
+ cfile);
}
void
static int
@@ -642,18 +651,24 @@ int
smb2_rmdir(const unsigned int xid, struct cifs_tcon *tcon, const char *name,
struct cifs_sb_info *cifs_sb)
{
+ struct cifsFileInfo *cfile;
+
+ cifs_get_writable_path(tcon, name, FIND_WR_WITH_DELETE, &cfile);
return smb2_compound_op(xid, tcon, cifs_sb, name, DELETE, FILE_OPEN,
CREATE_NOT_FILE, ACL_NO_MODE,
- NULL, SMB2_OP_RMDIR, NULL);
+ NULL, SMB2_OP_RMDIR, cfile);
}
int
smb2_unlink(const unsigned int xid, struct cifs_tcon *tcon, const char *name,
struct cifs_sb_info *cifs_sb)
{
+ struct cifsFileInfo *cfile;
+
+ cifs_get_writable_path(tcon, name, FIND_WR_WITH_DELETE, &cfile);
return smb2_compound_op(xid, tcon, cifs_sb, name, DELETE, FILE_OPEN,
CREATE_DELETE_ON_CLOSE | OPEN_REPARSE_POINT,
- ACL_NO_MODE, NULL, SMB2_OP_DELETE, NULL);
+ ACL_NO_MODE, NULL, SMB2_OP_DELETE, cfile);
}
static int
@@ -696,9 +711,12 @@ smb2_create_hardlink(const unsigned int xid, struct cifs_tcon *tcon,
const char *from_name, const char *to_name,
struct cifs_sb_info *cifs_sb)
{
+ struct cifsFileInfo *cfile;
+
+ cifs_get_writable_path(tcon, from_name, FIND_WR_ANY, &cfile);
return smb2_set_path_attr(xid, tcon, from_name, to_name, cifs_sb,
FILE_READ_ATTRIBUTES, SMB2_OP_HARDLINK,
- NULL);
+ cfile);
}
int
