From 9f8f9c774ad10aa1c15952c36f580d7e3711a100 Mon Sep 17 00:00:00 2001 From: Alexander Aring Date: Mon, 2 Nov 2020 20:04:17 -0500 Subject: fs: dlm: define max send buffer This patch will set the maximum transmit buffer size for rcom messages with "names" to 4096 bytes. It's a leftover change of commit 4798cbbfbd00 ("fs: dlm: rework receive handling"). Fact is that we cannot allocate a contiguous transmit buffer length above of 4096 bytes. It seems at some places the upper layer protocol will calculate according to dlm_config.ci_buffer_size the possible payload of a dlm recovery message. As compiler setting we will use now the maximum possible message which dlm can send out. Commit 4e192ee68e5af ("fs: dlm: disallow buffer size below default") disallow a buffer setting smaller than the 4096 bytes and above 4096 bytes is definitely wrong because we will then write out of buffer space as we cannot allocate a contiguous buffer above 4096 bytes. The ci_buffer_size is still there to define the possible maximum receive buffer size of a recvmsg() which should be at least the maximum possible dlm message size. Signed-off-by: Alexander Aring Signed-off-by: David Teigland --- fs/dlm/lockspace.c | 2 +- fs/dlm/lowcomms.h | 2 ++ fs/dlm/member.c | 2 +- fs/dlm/rcom.c | 6 +++--- 4 files changed, 7 insertions(+), 5 deletions(-) (limited to 'fs/dlm') diff --git a/fs/dlm/lockspace.c b/fs/dlm/lockspace.c index 624617c12250..561dcad08ad6 100644 --- a/fs/dlm/lockspace.c +++ b/fs/dlm/lockspace.c @@ -572,7 +572,7 @@ static int new_lockspace(const char *name, const char *cluster, mutex_init(&ls->ls_requestqueue_mutex); mutex_init(&ls->ls_clear_proc_locks); - ls->ls_recover_buf = kmalloc(dlm_config.ci_buffer_size, GFP_NOFS); + ls->ls_recover_buf = kmalloc(LOWCOMMS_MAX_TX_BUFFER_LEN, GFP_NOFS); if (!ls->ls_recover_buf) goto out_lkbidr; diff --git a/fs/dlm/lowcomms.h b/fs/dlm/lowcomms.h index 687b2894e469..0918f9376489 100644 --- a/fs/dlm/lowcomms.h +++ b/fs/dlm/lowcomms.h @@ -12,6 +12,8 @@ #ifndef __LOWCOMMS_DOT_H__ #define __LOWCOMMS_DOT_H__ +#define LOWCOMMS_MAX_TX_BUFFER_LEN 4096 + int dlm_lowcomms_start(void); void dlm_lowcomms_stop(void); void dlm_lowcomms_exit(void); diff --git a/fs/dlm/member.c b/fs/dlm/member.c index 7ad83deb4505..ceef3f2074ff 100644 --- a/fs/dlm/member.c +++ b/fs/dlm/member.c @@ -270,7 +270,7 @@ int dlm_slots_assign(struct dlm_ls *ls, int *num_slots, int *slots_size, log_slots(ls, gen, num, NULL, array, array_size); - max_slots = (dlm_config.ci_buffer_size - sizeof(struct dlm_rcom) - + max_slots = (LOWCOMMS_MAX_TX_BUFFER_LEN - sizeof(struct dlm_rcom) - sizeof(struct rcom_config)) / sizeof(struct rcom_slot); if (num > max_slots) { diff --git a/fs/dlm/rcom.c b/fs/dlm/rcom.c index 4daf5dc2b51c..73ddee5159d7 100644 --- a/fs/dlm/rcom.c +++ b/fs/dlm/rcom.c @@ -162,7 +162,7 @@ retry: set_rcom_status(ls, (struct rcom_status *)rc->rc_buf, status_flags); allow_sync_reply(ls, &rc->rc_id); - memset(ls->ls_recover_buf, 0, dlm_config.ci_buffer_size); + memset(ls->ls_recover_buf, 0, LOWCOMMS_MAX_TX_BUFFER_LEN); send_rcom(ls, mh, rc); @@ -284,7 +284,7 @@ retry: memcpy(rc->rc_buf, last_name, last_len); allow_sync_reply(ls, &rc->rc_id); - memset(ls->ls_recover_buf, 0, dlm_config.ci_buffer_size); + memset(ls->ls_recover_buf, 0, LOWCOMMS_MAX_TX_BUFFER_LEN); send_rcom(ls, mh, rc); @@ -304,7 +304,7 @@ static void receive_rcom_names(struct dlm_ls *ls, struct dlm_rcom *rc_in) nodeid = rc_in->rc_header.h_nodeid; inlen = rc_in->rc_header.h_length - sizeof(struct dlm_rcom); - outlen = dlm_config.ci_buffer_size - sizeof(struct dlm_rcom); + outlen = LOWCOMMS_MAX_TX_BUFFER_LEN - sizeof(struct dlm_rcom); error = create_rcom(ls, nodeid, DLM_RCOM_NAMES_REPLY, outlen, &rc, &mh); if (error) -- cgit v1.2.3