updated with ronnie's suggestion in for-next
(and added RB)
On Thu, Oct 13, 2022 at 1:39 AM ronnie sahlberg
<ronniesahlberg@xxxxxxxxx> wrote:
>
> On Thu, 13 Oct 2022 at 14:48, Steve French <smfrench@xxxxxxxxx> wrote:
> >
> > updated version of the patch attached. Shrunk slightly (e.g. removing
> > a few places where readability is only marginally improved but code is
> > exactly equivalent), but left in the conversions from ROUND_UP --->
> > ALIGN etc
> >
> > tentatively merged into cifs-2.6.git for-next
> >
> > Let me know if any objections or RB to add
>
> Remove the part of the patch that starts at line 265 in the patch.
> It changes the "allocate a buffer and memcpy to it to adjust for 2/4/6
> bytes of padding
> to happen unconditionally.
>
> In 25% of the cases when we reach this part the buffer will already be
> aligned at a 8 byte boundary
> and then we do not need to kzalloc and memcpy any data.
>
>
>
>
> >
> > On Sat, Sep 17, 2022 at 10:43 PM Enzo Matsumiya <ematsumiya@xxxxxxx> wrote:
> > >
> > > Improve code readability by using existing macros:
> > >
> > > Replace hardcoded alignment computations (e.g. (len + 7) & ~0x7) by
> > > ALIGN()/IS_ALIGNED() macros.
> > >
> > > Also replace (DIV_ROUND_UP(len, 8) * 8) with ALIGN(len, 8), which, if
> > > not optimized by the compiler, has the overhead of a multiplication
> > > and a division. Do the same for roundup() by replacing it by round_up()
> > > (division-less version, but requires the multiple to be a power of 2,
> > > which is always the case for us).
> > >
> > > And remove some unnecessary checks where !IS_ALIGNED() would fit, but
> > > calling round_up() directly is fine as it's a no-op if the value is
> > > already aligned.
> > >
> > > Signed-off-by: Enzo Matsumiya <ematsumiya@xxxxxxx>
> > > ---
> > > v2: drop performance claims, adjust commit title/message -- patch is the same
> > >
> > > fs/cifs/cifssmb.c | 7 +++---
> > > fs/cifs/connect.c | 11 ++++++--
> > > fs/cifs/sess.c | 18 +++++--------
> > > fs/cifs/smb2inode.c | 4 +--
> > > fs/cifs/smb2misc.c | 2 +-
> > > fs/cifs/smb2pdu.c | 61 +++++++++++++++++++--------------------------
> > > 6 files changed, 47 insertions(+), 56 deletions(-)
> > >
> > > diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
> > > index 7aa91e272027..addf3fc62aef 100644
> > > --- a/fs/cifs/cifssmb.c
> > > +++ b/fs/cifs/cifssmb.c
> > > @@ -2305,7 +2305,7 @@ int CIFSSMBRenameOpenFile(const unsigned int xid, struct cifs_tcon *pTcon,
> > > remap);
> > > }
> > > rename_info->target_name_len = cpu_to_le32(2 * len_of_str);
> > > - count = 12 /* sizeof(struct set_file_rename) */ + (2 * len_of_str);
> > > + count = sizeof(struct set_file_rename) + (2 * len_of_str);
> > > byte_count += count;
> > > pSMB->DataCount = cpu_to_le16(count);
> > > pSMB->TotalDataCount = pSMB->DataCount;
> > > @@ -2796,7 +2796,7 @@ CIFSSMBQuerySymLink(const unsigned int xid, struct cifs_tcon *tcon,
> > > cifs_dbg(FYI, "Invalid return data count on get reparse info ioctl\n");
> > > goto qreparse_out;
> > > }
> > > - end_of_smb = 2 + get_bcc(&pSMBr->hdr) + (char *)&pSMBr->ByteCount;
> > > + end_of_smb = sizeof(__le16) + get_bcc(&pSMBr->hdr) + (char *)&pSMBr->ByteCount;
> > > reparse_buf = (struct reparse_symlink_data *)
> > > ((char *)&pSMBr->hdr.Protocol + data_offset);
> > > if ((char *)reparse_buf >= end_of_smb) {
> > > @@ -3350,8 +3350,7 @@ validate_ntransact(char *buf, char **ppparm, char **ppdata,
> > > pSMBr = (struct smb_com_ntransact_rsp *)buf;
> > >
> > > bcc = get_bcc(&pSMBr->hdr);
> > > - end_of_smb = 2 /* sizeof byte count */ + bcc +
> > > - (char *)&pSMBr->ByteCount;
> > > + end_of_smb = sizeof(__le16) + bcc + (char *)&pSMBr->ByteCount;
> > >
> > > data_offset = le32_to_cpu(pSMBr->DataOffset);
> > > data_count = le32_to_cpu(pSMBr->DataCount);
> > > diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
> > > index 7ae6f2c08153..8a26ba7fc707 100644
> > > --- a/fs/cifs/connect.c
> > > +++ b/fs/cifs/connect.c
> > > @@ -2831,9 +2831,12 @@ ip_rfc1001_connect(struct TCP_Server_Info *server)
> > > * sessinit is sent but no second negprot
> > > */
> > > struct rfc1002_session_packet *ses_init_buf;
> > > + unsigned int req_noscope_len;
> > > struct smb_hdr *smb_buf;
> > > +
> > > ses_init_buf = kzalloc(sizeof(struct rfc1002_session_packet),
> > > GFP_KERNEL);
> > > +
> > > if (ses_init_buf) {
> > > ses_init_buf->trailer.session_req.called_len = 32;
> > >
> > > @@ -2869,8 +2872,12 @@ ip_rfc1001_connect(struct TCP_Server_Info *server)
> > > ses_init_buf->trailer.session_req.scope2 = 0;
> > > smb_buf = (struct smb_hdr *)ses_init_buf;
> > >
> > > - /* sizeof RFC1002_SESSION_REQUEST with no scope */
> > > - smb_buf->smb_buf_length = cpu_to_be32(0x81000044);
> > > + /* sizeof RFC1002_SESSION_REQUEST with no scopes */
> > > + req_noscope_len = sizeof(struct rfc1002_session_packet) - 2;
> > > +
> > > + /* == cpu_to_be32(0x81000044) */
> > > + smb_buf->smb_buf_length =
> > > + cpu_to_be32((RFC1002_SESSION_REQUEST << 24) | req_noscope_len);
> > > rc = smb_send(server, smb_buf, 0x44);
> > > kfree(ses_init_buf);
> > > /*
> > > diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
> > > index 3af3b05b6c74..951874928d70 100644
> > > --- a/fs/cifs/sess.c
> > > +++ b/fs/cifs/sess.c
> > > @@ -601,11 +601,6 @@ static void unicode_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
> > > /* BB FIXME add check that strings total less
> > > than 335 or will need to send them as arrays */
> > >
> > > - /* unicode strings, must be word aligned before the call */
> > > -/* if ((long) bcc_ptr % 2) {
> > > - *bcc_ptr = 0;
> > > - bcc_ptr++;
> > > - } */
> > > /* copy user */
> > > if (ses->user_name == NULL) {
> > > /* null user mount */
> > > @@ -1318,7 +1313,7 @@ sess_auth_ntlmv2(struct sess_data *sess_data)
> > > }
> > >
> > > if (ses->capabilities & CAP_UNICODE) {
> > > - if (sess_data->iov[0].iov_len % 2) {
> > > + if (!IS_ALIGNED(sess_data->iov[0].iov_len, 2)) {
> > > *bcc_ptr = 0;
> > > bcc_ptr++;
> > > }
> > > @@ -1358,7 +1353,7 @@ sess_auth_ntlmv2(struct sess_data *sess_data)
> > > /* no string area to decode, do nothing */
> > > } else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
> > > /* unicode string area must be word-aligned */
> > > - if (((unsigned long) bcc_ptr - (unsigned long) smb_buf) % 2) {
> > > + if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
> > > ++bcc_ptr;
> > > --bytes_remaining;
> > > }
> > > @@ -1442,8 +1437,7 @@ sess_auth_kerberos(struct sess_data *sess_data)
> > >
> > > if (ses->capabilities & CAP_UNICODE) {
> > > /* unicode strings must be word aligned */
> > > - if ((sess_data->iov[0].iov_len
> > > - + sess_data->iov[1].iov_len) % 2) {
> > > + if (!IS_ALIGNED(sess_data->iov[0].iov_len + sess_data->iov[1].iov_len, 2)) {
> > > *bcc_ptr = 0;
> > > bcc_ptr++;
> > > }
> > > @@ -1494,7 +1488,7 @@ sess_auth_kerberos(struct sess_data *sess_data)
> > > /* no string area to decode, do nothing */
> > > } else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
> > > /* unicode string area must be word-aligned */
> > > - if (((unsigned long) bcc_ptr - (unsigned long) smb_buf) % 2) {
> > > + if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
> > > ++bcc_ptr;
> > > --bytes_remaining;
> > > }
> > > @@ -1546,7 +1540,7 @@ _sess_auth_rawntlmssp_assemble_req(struct sess_data *sess_data)
> > >
> > > bcc_ptr = sess_data->iov[2].iov_base;
> > > /* unicode strings must be word aligned */
> > > - if ((sess_data->iov[0].iov_len + sess_data->iov[1].iov_len) % 2) {
> > > + if (!IS_ALIGNED(sess_data->iov[0].iov_len + sess_data->iov[1].iov_len, 2)) {
> > > *bcc_ptr = 0;
> > > bcc_ptr++;
> > > }
> > > @@ -1747,7 +1741,7 @@ sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data)
> > > /* no string area to decode, do nothing */
> > > } else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
> > > /* unicode string area must be word-aligned */
> > > - if (((unsigned long) bcc_ptr - (unsigned long) smb_buf) % 2) {
> > > + if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
> > > ++bcc_ptr;
> > > --bytes_remaining;
> > > }
> > > diff --git a/fs/cifs/smb2inode.c b/fs/cifs/smb2inode.c
> > > index b83f59051b26..4eefbe574b82 100644
> > > --- a/fs/cifs/smb2inode.c
> > > +++ b/fs/cifs/smb2inode.c
> > > @@ -207,7 +207,7 @@ smb2_compound_op(const unsigned int xid, struct cifs_tcon *tcon,
> > > rqst[num_rqst].rq_iov = &vars->si_iov[0];
> > > rqst[num_rqst].rq_nvec = 1;
> > >
> > > - size[0] = 1; /* sizeof __u8 See MS-FSCC section 2.4.11 */
> > > + size[0] = sizeof(u8); /* See MS-FSCC section 2.4.11 */
> > > data[0] = &delete_pending[0];
> > >
> > > rc = SMB2_set_info_init(tcon, server,
> > > @@ -225,7 +225,7 @@ smb2_compound_op(const unsigned int xid, struct cifs_tcon *tcon,
> > > rqst[num_rqst].rq_iov = &vars->si_iov[0];
> > > rqst[num_rqst].rq_nvec = 1;
> > >
> > > - size[0] = 8; /* sizeof __le64 */
> > > + size[0] = sizeof(__le64);
> > > data[0] = ptr;
> > >
> > > rc = SMB2_set_info_init(tcon, server,
> > > diff --git a/fs/cifs/smb2misc.c b/fs/cifs/smb2misc.c
> > > index d73e5672aac4..258b01306d85 100644
> > > --- a/fs/cifs/smb2misc.c
> > > +++ b/fs/cifs/smb2misc.c
> > > @@ -248,7 +248,7 @@ smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *server)
> > > * Some windows servers (win2016) will pad also the final
> > > * PDU in a compound to 8 bytes.
> > > */
> > > - if (((calc_len + 7) & ~7) == len)
> > > + if (ALIGN(calc_len, 8) == len)
> > > return 0;
> > >
> > > /*
> > > diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
> > > index 6352ab32c7e7..5da0b596c8a0 100644
> > > --- a/fs/cifs/smb2pdu.c
> > > +++ b/fs/cifs/smb2pdu.c
> > > @@ -466,15 +466,14 @@ build_signing_ctxt(struct smb2_signing_capabilities *pneg_ctxt)
> > > /*
> > > * Context Data length must be rounded to multiple of 8 for some servers
> > > */
> > > - pneg_ctxt->DataLength = cpu_to_le16(DIV_ROUND_UP(
> > > - sizeof(struct smb2_signing_capabilities) -
> > > - sizeof(struct smb2_neg_context) +
> > > - (num_algs * 2 /* sizeof u16 */), 8) * 8);
> > > + pneg_ctxt->DataLength = cpu_to_le16(ALIGN(sizeof(struct smb2_signing_capabilities) -
> > > + sizeof(struct smb2_neg_context) +
> > > + (num_algs * sizeof(u16)), 8));
> > > pneg_ctxt->SigningAlgorithmCount = cpu_to_le16(num_algs);
> > > pneg_ctxt->SigningAlgorithms[0] = cpu_to_le16(SIGNING_ALG_AES_CMAC);
> > >
> > > - ctxt_len += 2 /* sizeof le16 */ * num_algs;
> > > - ctxt_len = DIV_ROUND_UP(ctxt_len, 8) * 8;
> > > + ctxt_len += sizeof(__le16) * num_algs;
> > > + ctxt_len = ALIGN(ctxt_len, 8);
> > > return ctxt_len;
> > > /* TBD add SIGNING_ALG_AES_GMAC and/or SIGNING_ALG_HMAC_SHA256 */
> > > }
> > > @@ -511,8 +510,7 @@ build_netname_ctxt(struct smb2_netname_neg_context *pneg_ctxt, char *hostname)
> > > /* copy up to max of first 100 bytes of server name to NetName field */
> > > pneg_ctxt->DataLength = cpu_to_le16(2 * cifs_strtoUTF16(pneg_ctxt->NetName, hostname, 100, cp));
> > > /* context size is DataLength + minimal smb2_neg_context */
> > > - return DIV_ROUND_UP(le16_to_cpu(pneg_ctxt->DataLength) +
> > > - sizeof(struct smb2_neg_context), 8) * 8;
> > > + return ALIGN(le16_to_cpu(pneg_ctxt->DataLength) + sizeof(struct smb2_neg_context), 8);
> > > }
> > >
> > > static void
> > > @@ -557,18 +555,18 @@ assemble_neg_contexts(struct smb2_negotiate_req *req,
> > > * round up total_len of fixed part of SMB3 negotiate request to 8
> > > * byte boundary before adding negotiate contexts
> > > */
> > > - *total_len = roundup(*total_len, 8);
> > > + *total_len = ALIGN(*total_len, 8);
> > >
> > > pneg_ctxt = (*total_len) + (char *)req;
> > > req->NegotiateContextOffset = cpu_to_le32(*total_len);
> > >
> > > build_preauth_ctxt((struct smb2_preauth_neg_context *)pneg_ctxt);
> > > - ctxt_len = DIV_ROUND_UP(sizeof(struct smb2_preauth_neg_context), 8) * 8;
> > > + ctxt_len = ALIGN(sizeof(struct smb2_preauth_neg_context), 8);
> > > *total_len += ctxt_len;
> > > pneg_ctxt += ctxt_len;
> > >
> > > build_encrypt_ctxt((struct smb2_encryption_neg_context *)pneg_ctxt);
> > > - ctxt_len = DIV_ROUND_UP(sizeof(struct smb2_encryption_neg_context), 8) * 8;
> > > + ctxt_len = ALIGN(sizeof(struct smb2_encryption_neg_context), 8);
> > > *total_len += ctxt_len;
> > > pneg_ctxt += ctxt_len;
> > >
> > > @@ -595,9 +593,7 @@ assemble_neg_contexts(struct smb2_negotiate_req *req,
> > > if (server->compress_algorithm) {
> > > build_compression_ctxt((struct smb2_compression_capabilities_context *)
> > > pneg_ctxt);
> > > - ctxt_len = DIV_ROUND_UP(
> > > - sizeof(struct smb2_compression_capabilities_context),
> > > - 8) * 8;
> > > + ctxt_len = ALIGN(sizeof(struct smb2_compression_capabilities_context), 8);
> > > *total_len += ctxt_len;
> > > pneg_ctxt += ctxt_len;
> > > neg_context_count++;
> > > @@ -780,7 +776,7 @@ static int smb311_decode_neg_context(struct smb2_negotiate_rsp *rsp,
> > > if (rc)
> > > break;
> > > /* offsets must be 8 byte aligned */
> > > - clen = (clen + 7) & ~0x7;
> > > + clen = ALIGN(clen, 8);
> > > offset += clen + sizeof(struct smb2_neg_context);
> > > len_of_ctxts -= clen;
> > > }
> > > @@ -2413,7 +2409,7 @@ create_sd_buf(umode_t mode, bool set_owner, unsigned int *len)
> > > unsigned int group_offset = 0;
> > > struct smb3_acl acl;
> > >
> > > - *len = roundup(sizeof(struct crt_sd_ctxt) + (sizeof(struct cifs_ace) * 4), 8);
> > > + *len = round_up(sizeof(struct crt_sd_ctxt) + (sizeof(struct cifs_ace) * 4), 8);
> > >
> > > if (set_owner) {
> > > /* sizeof(struct owner_group_sids) is already multiple of 8 so no need to round */
> > > @@ -2487,7 +2483,7 @@ create_sd_buf(umode_t mode, bool set_owner, unsigned int *len)
> > > memcpy(aclptr, &acl, sizeof(struct smb3_acl));
> > >
> > > buf->ccontext.DataLength = cpu_to_le32(ptr - (__u8 *)&buf->sd);
> > > - *len = roundup(ptr - (__u8 *)buf, 8);
> > > + *len = round_up((unsigned int)(ptr - (__u8 *)buf), 8);
> > >
> > > return buf;
> > > }
> > > @@ -2581,7 +2577,7 @@ alloc_path_with_tree_prefix(__le16 **out_path, int *out_size, int *out_len,
> > > * final path needs to be 8-byte aligned as specified in
> > > * MS-SMB2 2.2.13 SMB2 CREATE Request.
> > > */
> > > - *out_size = roundup(*out_len * sizeof(__le16), 8);
> > > + *out_size = round_up(*out_len * sizeof(__le16), 8);
> > > *out_path = kzalloc(*out_size + sizeof(__le16) /* null */, GFP_KERNEL);
> > > if (!*out_path)
> > > return -ENOMEM;
> > > @@ -2687,20 +2683,17 @@ int smb311_posix_mkdir(const unsigned int xid, struct inode *inode,
> > > uni_path_len = (2 * UniStrnlen((wchar_t *)utf16_path, PATH_MAX)) + 2;
> > > /* MUST set path len (NameLength) to 0 opening root of share */
> > > req->NameLength = cpu_to_le16(uni_path_len - 2);
> > > - if (uni_path_len % 8 != 0) {
> > > - copy_size = roundup(uni_path_len, 8);
> > > - copy_path = kzalloc(copy_size, GFP_KERNEL);
> > > - if (!copy_path) {
> > > - rc = -ENOMEM;
> > > - goto err_free_req;
> > > - }
> > > - memcpy((char *)copy_path, (const char *)utf16_path,
> > > - uni_path_len);
> > > - uni_path_len = copy_size;
> > > - /* free before overwriting resource */
> > > - kfree(utf16_path);
> > > - utf16_path = copy_path;
> > > + copy_size = round_up(uni_path_len, 8);
> > > + copy_path = kzalloc(copy_size, GFP_KERNEL);
> > > + if (!copy_path) {
> > > + rc = -ENOMEM;
> > > + goto err_free_req;
> > > }
> > > + memcpy((char *)copy_path, (const char *)utf16_path, uni_path_len);
> > > + uni_path_len = copy_size;
> > > + /* free before overwriting resource */
> > > + kfree(utf16_path);
> > > + utf16_path = copy_path;
> > > }
> > >
> > > iov[1].iov_len = uni_path_len;
> > > @@ -2826,9 +2819,7 @@ SMB2_open_init(struct cifs_tcon *tcon, struct TCP_Server_Info *server,
> > > uni_path_len = (2 * UniStrnlen((wchar_t *)path, PATH_MAX)) + 2;
> > > /* MUST set path len (NameLength) to 0 opening root of share */
> > > req->NameLength = cpu_to_le16(uni_path_len - 2);
> > > - copy_size = uni_path_len;
> > > - if (copy_size % 8 != 0)
> > > - copy_size = roundup(copy_size, 8);
> > > + copy_size = round_up(uni_path_len, 8);
> > > copy_path = kzalloc(copy_size, GFP_KERNEL);
> > > if (!copy_path)
> > > return -ENOMEM;
> > > @@ -4090,7 +4081,7 @@ smb2_new_read_req(void **buf, unsigned int *total_len,
> > > if (request_type & CHAINED_REQUEST) {
> > > if (!(request_type & END_OF_CHAIN)) {
> > > /* next 8-byte aligned request */
> > > - *total_len = DIV_ROUND_UP(*total_len, 8) * 8;
> > > + *total_len = ALIGN(*total_len, 8);
> > > shdr->NextCommand = cpu_to_le32(*total_len);
> > > } else /* END_OF_CHAIN */
> > > shdr->NextCommand = 0;
> > > --
> > > 2.35.3
> > >
> >
> >
> > --
> > Thanks,
> >
> > Steve
--
Thanks,
Steve
