4.19-stable review patch. If anyone has any objections, please let me know.
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From: Jakob Koschel jakobkoschel@gmail.com
[ Upstream commit dc1acd5c94699389a9ed023e94dd860c846ea1f6 ]
To move the list iterator variable into the list_for_each_entry_*() macro in the future it should be avoided to use the list iterator variable after the loop body.
To *never* use the list iterator variable after the loop it was concluded to use a separate iterator variable instead of a found boolean [1].
This removes the need to use a found variable and simply checking if the variable was set, can determine if the break/goto was hit.
Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWX... [1] Signed-off-by: Jakob Koschel jakobkoschel@gmail.com Signed-off-by: Alexander Aring aahringo@redhat.com Signed-off-by: David Teigland teigland@redhat.com Stable-dep-of: 57e2c2f2d94c ("fs: dlm: fix mismatch of plock results from userspace") Signed-off-by: Sasha Levin sashal@kernel.org --- fs/dlm/lock.c | 53 +++++++++++++++++++++++------------------------- fs/dlm/plock.c | 24 +++++++++++----------- fs/dlm/recover.c | 39 +++++++++++++++++------------------ 3 files changed, 56 insertions(+), 60 deletions(-)
diff --git a/fs/dlm/lock.c b/fs/dlm/lock.c index d4e204473e76b..0864481d8551c 100644 --- a/fs/dlm/lock.c +++ b/fs/dlm/lock.c @@ -1858,7 +1858,7 @@ static void del_timeout(struct dlm_lkb *lkb) void dlm_scan_timeout(struct dlm_ls *ls) { struct dlm_rsb *r; - struct dlm_lkb *lkb; + struct dlm_lkb *lkb = NULL, *iter; int do_cancel, do_warn; s64 wait_us;
@@ -1869,27 +1869,28 @@ void dlm_scan_timeout(struct dlm_ls *ls) do_cancel = 0; do_warn = 0; mutex_lock(&ls->ls_timeout_mutex); - list_for_each_entry(lkb, &ls->ls_timeout, lkb_time_list) { + list_for_each_entry(iter, &ls->ls_timeout, lkb_time_list) {
wait_us = ktime_to_us(ktime_sub(ktime_get(), - lkb->lkb_timestamp)); + iter->lkb_timestamp));
- if ((lkb->lkb_exflags & DLM_LKF_TIMEOUT) && - wait_us >= (lkb->lkb_timeout_cs * 10000)) + if ((iter->lkb_exflags & DLM_LKF_TIMEOUT) && + wait_us >= (iter->lkb_timeout_cs * 10000)) do_cancel = 1;
- if ((lkb->lkb_flags & DLM_IFL_WATCH_TIMEWARN) && + if ((iter->lkb_flags & DLM_IFL_WATCH_TIMEWARN) && wait_us >= dlm_config.ci_timewarn_cs * 10000) do_warn = 1;
if (!do_cancel && !do_warn) continue; - hold_lkb(lkb); + hold_lkb(iter); + lkb = iter; break; } mutex_unlock(&ls->ls_timeout_mutex);
- if (!do_cancel && !do_warn) + if (!lkb) break;
r = lkb->lkb_resource; @@ -5243,21 +5244,18 @@ void dlm_recover_waiters_pre(struct dlm_ls *ls)
static struct dlm_lkb *find_resend_waiter(struct dlm_ls *ls) { - struct dlm_lkb *lkb; - int found = 0; + struct dlm_lkb *lkb = NULL, *iter;
mutex_lock(&ls->ls_waiters_mutex); - list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) { - if (lkb->lkb_flags & DLM_IFL_RESEND) { - hold_lkb(lkb); - found = 1; + list_for_each_entry(iter, &ls->ls_waiters, lkb_wait_reply) { + if (iter->lkb_flags & DLM_IFL_RESEND) { + hold_lkb(iter); + lkb = iter; break; } } mutex_unlock(&ls->ls_waiters_mutex);
- if (!found) - lkb = NULL; return lkb; }
@@ -5916,37 +5914,36 @@ int dlm_user_adopt_orphan(struct dlm_ls *ls, struct dlm_user_args *ua_tmp, int mode, uint32_t flags, void *name, unsigned int namelen, unsigned long timeout_cs, uint32_t *lkid) { - struct dlm_lkb *lkb; + struct dlm_lkb *lkb = NULL, *iter; struct dlm_user_args *ua; int found_other_mode = 0; - int found = 0; int rv = 0;
mutex_lock(&ls->ls_orphans_mutex); - list_for_each_entry(lkb, &ls->ls_orphans, lkb_ownqueue) { - if (lkb->lkb_resource->res_length != namelen) + list_for_each_entry(iter, &ls->ls_orphans, lkb_ownqueue) { + if (iter->lkb_resource->res_length != namelen) continue; - if (memcmp(lkb->lkb_resource->res_name, name, namelen)) + if (memcmp(iter->lkb_resource->res_name, name, namelen)) continue; - if (lkb->lkb_grmode != mode) { + if (iter->lkb_grmode != mode) { found_other_mode = 1; continue; }
- found = 1; - list_del_init(&lkb->lkb_ownqueue); - lkb->lkb_flags &= ~DLM_IFL_ORPHAN; - *lkid = lkb->lkb_id; + lkb = iter; + list_del_init(&iter->lkb_ownqueue); + iter->lkb_flags &= ~DLM_IFL_ORPHAN; + *lkid = iter->lkb_id; break; } mutex_unlock(&ls->ls_orphans_mutex);
- if (!found && found_other_mode) { + if (!lkb && found_other_mode) { rv = -EAGAIN; goto out; }
- if (!found) { + if (!lkb) { rv = -ENOENT; goto out; } diff --git a/fs/dlm/plock.c b/fs/dlm/plock.c index 5f3643890f1e0..7e26e677c6b24 100644 --- a/fs/dlm/plock.c +++ b/fs/dlm/plock.c @@ -437,9 +437,9 @@ static ssize_t dev_read(struct file *file, char __user *u, size_t count, static ssize_t dev_write(struct file *file, const char __user *u, size_t count, loff_t *ppos) { + struct plock_op *op = NULL, *iter; struct dlm_plock_info info; - struct plock_op *op; - int found = 0, do_callback = 0; + int do_callback = 0;
if (count != sizeof(info)) return -EINVAL; @@ -451,23 +451,23 @@ static ssize_t dev_write(struct file *file, const char __user *u, size_t count, return -EINVAL;
spin_lock(&ops_lock); - list_for_each_entry(op, &recv_list, list) { - if (op->info.fsid == info.fsid && - op->info.number == info.number && - op->info.owner == info.owner) { - list_del_init(&op->list); - memcpy(&op->info, &info, sizeof(info)); - if (op->data) + list_for_each_entry(iter, &recv_list, list) { + if (iter->info.fsid == info.fsid && + iter->info.number == info.number && + iter->info.owner == info.owner) { + list_del_init(&iter->list); + memcpy(&iter->info, &info, sizeof(info)); + if (iter->data) do_callback = 1; else - op->done = 1; - found = 1; + iter->done = 1; + op = iter; break; } } spin_unlock(&ops_lock);
- if (found) { + if (op) { if (do_callback) dlm_plock_callback(op); else diff --git a/fs/dlm/recover.c b/fs/dlm/recover.c index ce2aa54ca2e24..98b710cc9cf30 100644 --- a/fs/dlm/recover.c +++ b/fs/dlm/recover.c @@ -734,10 +734,9 @@ void dlm_recovered_lock(struct dlm_rsb *r)
static void recover_lvb(struct dlm_rsb *r) { - struct dlm_lkb *lkb, *high_lkb = NULL; + struct dlm_lkb *big_lkb = NULL, *iter, *high_lkb = NULL; uint32_t high_seq = 0; int lock_lvb_exists = 0; - int big_lock_exists = 0; int lvblen = r->res_ls->ls_lvblen;
if (!rsb_flag(r, RSB_NEW_MASTER2) && @@ -753,37 +752,37 @@ static void recover_lvb(struct dlm_rsb *r) /* we are the new master, so figure out if VALNOTVALID should be set, and set the rsb lvb from the best lkb available. */
- list_for_each_entry(lkb, &r->res_grantqueue, lkb_statequeue) { - if (!(lkb->lkb_exflags & DLM_LKF_VALBLK)) + list_for_each_entry(iter, &r->res_grantqueue, lkb_statequeue) { + if (!(iter->lkb_exflags & DLM_LKF_VALBLK)) continue;
lock_lvb_exists = 1;
- if (lkb->lkb_grmode > DLM_LOCK_CR) { - big_lock_exists = 1; + if (iter->lkb_grmode > DLM_LOCK_CR) { + big_lkb = iter; goto setflag; }
- if (((int)lkb->lkb_lvbseq - (int)high_seq) >= 0) { - high_lkb = lkb; - high_seq = lkb->lkb_lvbseq; + if (((int)iter->lkb_lvbseq - (int)high_seq) >= 0) { + high_lkb = iter; + high_seq = iter->lkb_lvbseq; } }
- list_for_each_entry(lkb, &r->res_convertqueue, lkb_statequeue) { - if (!(lkb->lkb_exflags & DLM_LKF_VALBLK)) + list_for_each_entry(iter, &r->res_convertqueue, lkb_statequeue) { + if (!(iter->lkb_exflags & DLM_LKF_VALBLK)) continue;
lock_lvb_exists = 1;
- if (lkb->lkb_grmode > DLM_LOCK_CR) { - big_lock_exists = 1; + if (iter->lkb_grmode > DLM_LOCK_CR) { + big_lkb = iter; goto setflag; }
- if (((int)lkb->lkb_lvbseq - (int)high_seq) >= 0) { - high_lkb = lkb; - high_seq = lkb->lkb_lvbseq; + if (((int)iter->lkb_lvbseq - (int)high_seq) >= 0) { + high_lkb = iter; + high_seq = iter->lkb_lvbseq; } }
@@ -792,7 +791,7 @@ static void recover_lvb(struct dlm_rsb *r) goto out;
/* lvb is invalidated if only NL/CR locks remain */ - if (!big_lock_exists) + if (!big_lkb) rsb_set_flag(r, RSB_VALNOTVALID);
if (!r->res_lvbptr) { @@ -801,9 +800,9 @@ static void recover_lvb(struct dlm_rsb *r) goto out; }
- if (big_lock_exists) { - r->res_lvbseq = lkb->lkb_lvbseq; - memcpy(r->res_lvbptr, lkb->lkb_lvbptr, lvblen); + if (big_lkb) { + r->res_lvbseq = big_lkb->lkb_lvbseq; + memcpy(r->res_lvbptr, big_lkb->lkb_lvbptr, lvblen); } else if (high_lkb) { r->res_lvbseq = high_lkb->lkb_lvbseq; memcpy(r->res_lvbptr, high_lkb->lkb_lvbptr, lvblen);