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smb: server: make consitent use of spin_lock_irq{save,restore}() in transport_rdma.c

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There is a mix of using spin_lock() and spin_lock_irq(), which
is confusing as IB_POLL_WORKQUEUE is used and no code would
be called from any interrupt. So using spin_lock() or even
mutexes would be ok.

But we'll soon share common code with the client, which uses
IB_POLL_SOFTIRQ.

And Documentation/kernel-hacking/locking.rst section
"Cheat Sheet For Locking" says:

-  Otherwise (== data can be touched in an interrupt), use
   spin_lock_irqsave() and
   spin_unlock_irqrestore().

So in order to keep it simple and safe we use that version
now. It will help merging functions into common code and
have consistent locking in all cases.

Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Cc: Steve French <smfrench@gmail.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
This commit is contained in:
Stefan Metzmacher
2025-08-27 15:54:35 +02:00
committed by Steve French
parent 0491f26f89
commit 8aa23bae60
1 changed files with 24 additions and 15 deletions
Download Patch File Download Diff File Expand all files Collapse all files

39
fs/smb/server/transport_rdma.c
View File

@@ -150,21 +150,24 @@ static struct
smbdirect_recv_io *get_free_recvmsg(struct smbdirect_socket *sc)
{
struct smbdirect_recv_io *recvmsg = NULL;
unsigned long flags;
spin_lock(&sc->recv_io.free.lock);
spin_lock_irqsave(&sc->recv_io.free.lock, flags);
if (!list_empty(&sc->recv_io.free.list)) {
recvmsg = list_first_entry(&sc->recv_io.free.list,
struct smbdirect_recv_io,
list);
list_del(&recvmsg->list);
}
spin_unlock(&sc->recv_io.free.lock);
spin_unlock_irqrestore(&sc->recv_io.free.lock, flags);
return recvmsg;
}
static void put_recvmsg(struct smbdirect_socket *sc,
struct smbdirect_recv_io *recvmsg)
{
unsigned long flags;
if (likely(recvmsg->sge.length != 0)) {
ib_dma_unmap_single(sc->ib.dev,
recvmsg->sge.addr,
@@ -173,9 +176,9 @@ static void put_recvmsg(struct smbdirect_socket *sc,
recvmsg->sge.length = 0;
}
spin_lock(&sc->recv_io.free.lock);
spin_lock_irqsave(&sc->recv_io.free.lock, flags);
list_add(&recvmsg->list, &sc->recv_io.free.list);
spin_unlock(&sc->recv_io.free.lock);
spin_unlock_irqrestore(&sc->recv_io.free.lock, flags);
queue_work(sc->workqueue, &sc->recv_io.posted.refill_work);
}
@@ -184,7 +187,9 @@ static void enqueue_reassembly(struct smbdirect_socket *sc,
struct smbdirect_recv_io *recvmsg,
int data_length)
{
spin_lock(&sc->recv_io.reassembly.lock);
unsigned long flags;
spin_lock_irqsave(&sc->recv_io.reassembly.lock, flags);
list_add_tail(&recvmsg->list, &sc->recv_io.reassembly.list);
sc->recv_io.reassembly.queue_length++;
/*
@@ -195,7 +200,7 @@ static void enqueue_reassembly(struct smbdirect_socket *sc,
*/
virt_wmb();
sc->recv_io.reassembly.data_length += data_length;
spin_unlock(&sc->recv_io.reassembly.lock);
spin_unlock_irqrestore(&sc->recv_io.reassembly.lock, flags);
}
static struct smbdirect_recv_io *get_first_reassembly(struct smbdirect_socket *sc)
@@ -468,14 +473,16 @@ static void free_transport(struct smb_direct_transport *t)
ksmbd_debug(RDMA, "drain the reassembly queue\n");
do {
spin_lock(&sc->recv_io.reassembly.lock);
unsigned long flags;
spin_lock_irqsave(&sc->recv_io.reassembly.lock, flags);
recvmsg = get_first_reassembly(sc);
if (recvmsg) {
list_del(&recvmsg->list);
spin_unlock(&sc->recv_io.reassembly.lock);
spin_unlock_irqrestore(&sc->recv_io.reassembly.lock, flags);
put_recvmsg(sc, recvmsg);
} else {
spin_unlock(&sc->recv_io.reassembly.lock);
spin_unlock_irqrestore(&sc->recv_io.reassembly.lock, flags);
}
} while (recvmsg);
sc->recv_io.reassembly.data_length = 0;
@@ -768,6 +775,7 @@ static int smb_direct_read(struct ksmbd_transport *t, char *buf,
if (sc->recv_io.reassembly.data_length >= size) {
int queue_length;
int queue_removed = 0;
unsigned long flags;
/*
* Need to make sure reassembly_data_length is read before
@@ -823,9 +831,9 @@ static int smb_direct_read(struct ksmbd_transport *t, char *buf,
if (queue_length) {
list_del(&recvmsg->list);
} else {
spin_lock_irq(&sc->recv_io.reassembly.lock);
spin_lock_irqsave(&sc->recv_io.reassembly.lock, flags);
list_del(&recvmsg->list);
spin_unlock_irq(&sc->recv_io.reassembly.lock);
spin_unlock_irqrestore(&sc->recv_io.reassembly.lock, flags);
}
queue_removed++;
put_recvmsg(sc, recvmsg);
@@ -838,10 +846,10 @@ static int smb_direct_read(struct ksmbd_transport *t, char *buf,
data_read += to_copy;
}
spin_lock_irq(&sc->recv_io.reassembly.lock);
spin_lock_irqsave(&sc->recv_io.reassembly.lock, flags);
sc->recv_io.reassembly.data_length -= data_read;
sc->recv_io.reassembly.queue_length -= queue_removed;
spin_unlock_irq(&sc->recv_io.reassembly.lock);
spin_unlock_irqrestore(&sc->recv_io.reassembly.lock, flags);
sc->recv_io.reassembly.first_entry_offset = offset;
ksmbd_debug(RDMA,
@@ -2107,6 +2115,7 @@ static int smb_direct_prepare(struct ksmbd_transport *t)
struct smbdirect_socket_parameters *sp = &sc->parameters;
struct smbdirect_recv_io *recvmsg;
struct smbdirect_negotiate_req *req;
unsigned long flags;
int ret;
/*
@@ -2153,10 +2162,10 @@ static int smb_direct_prepare(struct ksmbd_transport *t)
ret = smb_direct_send_negotiate_response(sc, ret);
out:
spin_lock_irq(&sc->recv_io.reassembly.lock);
spin_lock_irqsave(&sc->recv_io.reassembly.lock, flags);
sc->recv_io.reassembly.queue_length--;
list_del(&recvmsg->list);
spin_unlock_irq(&sc->recv_io.reassembly.lock);
spin_unlock_irqrestore(&sc->recv_io.reassembly.lock, flags);
put_recvmsg(sc, recvmsg);
return ret;