diff options
| -rw-r--r-- | fs/cifs/smb2glob.h | 10 | ||||
| -rw-r--r-- | fs/cifs/smb2pdu.c | 18 |
2 files changed, 27 insertions, 1 deletions
diff --git a/fs/cifs/smb2glob.h b/fs/cifs/smb2glob.h index 0ffa18094335..238759c146ba 100644 --- a/fs/cifs/smb2glob.h +++ b/fs/cifs/smb2glob.h @@ -61,4 +61,14 @@ /* Maximum buffer size value we can send with 1 credit */ #define SMB2_MAX_BUFFER_SIZE 65536 +/* + * Maximum number of credits to keep available. + * This value is chosen somewhat arbitrarily. The Windows client + * defaults to 128 credits, the Windows server allows clients up to + * 512 credits, and the NetApp server does not limit clients at all. + * Choose a high enough value such that the client shouldn't limit + * performance. + */ +#define SMB2_MAX_CREDITS_AVAILABLE 32000 + #endif /* _SMB2_GLOB_H */ diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index 29e06db5f187..967a7904fb8f 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -100,7 +100,21 @@ smb2_hdr_assemble(struct smb2_hdr *hdr, __le16 smb2_cmd /* command */ , hdr->ProtocolId = SMB2_PROTO_NUMBER; hdr->StructureSize = cpu_to_le16(64); hdr->Command = smb2_cmd; - hdr->CreditRequest = cpu_to_le16(2); /* BB make this dynamic */ + if (tcon && tcon->ses && tcon->ses->server) { + struct TCP_Server_Info *server = tcon->ses->server; + + spin_lock(&server->req_lock); + /* Request up to 2 credits but don't go over the limit. */ + if (server->credits >= SMB2_MAX_CREDITS_AVAILABLE) + hdr->CreditRequest = cpu_to_le16(0); + else + hdr->CreditRequest = cpu_to_le16( + min_t(int, SMB2_MAX_CREDITS_AVAILABLE - + server->credits, 2)); + spin_unlock(&server->req_lock); + } else { + hdr->CreditRequest = cpu_to_le16(2); + } hdr->ProcessId = cpu_to_le32((__u16)current->tgid); if (!tcon) @@ -2057,6 +2071,7 @@ smb2_async_readv(struct cifs_readdata *rdata) if (rdata->credits) { buf->CreditCharge = cpu_to_le16(DIV_ROUND_UP(rdata->bytes, SMB2_MAX_BUFFER_SIZE)); + buf->CreditRequest = buf->CreditCharge; spin_lock(&server->req_lock); server->credits += rdata->credits - le16_to_cpu(buf->CreditCharge); @@ -2243,6 +2258,7 @@ smb2_async_writev(struct cifs_writedata *wdata, if (wdata->credits) { req->hdr.CreditCharge = cpu_to_le16(DIV_ROUND_UP(wdata->bytes, SMB2_MAX_BUFFER_SIZE)); + req->hdr.CreditRequest = req->hdr.CreditCharge; spin_lock(&server->req_lock); server->credits += wdata->credits - le16_to_cpu(req->hdr.CreditCharge); |