diff options
Diffstat (limited to 'usr/src/uts/common/io/devpoll.c')
| -rw-r--r-- | usr/src/uts/common/io/devpoll.c | 46 |
1 files changed, 30 insertions, 16 deletions
diff --git a/usr/src/uts/common/io/devpoll.c b/usr/src/uts/common/io/devpoll.c index 764636e218..a474b67810 100644 --- a/usr/src/uts/common/io/devpoll.c +++ b/usr/src/uts/common/io/devpoll.c @@ -741,13 +741,6 @@ dpwrite(dev_t dev, struct uio *uiop, cred_t *credp) error = EBADF; break; } - - /* - * To (greatly) reduce EEXIST false - * positives, we denote that this - * fp has been epoll()'d; see below. - */ - fp->f_flag2 |= FEPOLLED; } pdp = pcache_alloc_fd(0); @@ -761,7 +754,7 @@ dpwrite(dev_t dev, struct uio *uiop, cred_t *credp) * check (imperfectly) by checking if we both * have the file descriptor cached and the * file pointer that correponds to the file - * descriptor matches our cached value. (If + * descriptor matches our cached value. If * there is a pointer mismatch, the file * descriptor was closed without being removed. * The converse is clearly not true, however, @@ -778,14 +771,26 @@ dpwrite(dev_t dev, struct uio *uiop, cred_t *credp) * then, the file descriptor must be closed and * reused in a relatively tight time span.) */ - if ((dpep->dpe_flag & DP_ISEPOLLCOMPAT) && - pdp->pd_fp != NULL && - (fp = getf(fd)) != NULL && - fp == pdp->pd_fp && - (fp->f_flag2 & FEPOLLED)) { - error = EEXIST; - releasef(fd); - break; + if (dpep->dpe_flag & DP_ISEPOLLCOMPAT) { + if (pdp->pd_fp != NULL && + (fp = getf(fd)) != NULL && + fp == pdp->pd_fp && + (fp->f_flag2 & FEPOLLED)) { + error = EEXIST; + releasef(fd); + break; + } + + /* + * We have decided that the cached + * information was stale: it either + * didn't match, or the fp had never + * actually been epoll()'d on before. + * We need to now clear our pd_events + * to assure that we don't mistakenly + * operate on cached event disposition. + */ + pdp->pd_events = 0; } } @@ -816,6 +821,15 @@ dpwrite(dev_t dev, struct uio *uiop, cred_t *credp) pdp->pd_events |= pfdp->events; continue; } + + /* + * To (greatly) reduce EEXIST false positives, we + * denote that this fp has been epoll()'d. We do this + * regardless of epoll compatibility mode, as the flag + * is harmless if not in epoll compatibility mode. + */ + fp->f_flag2 |= FEPOLLED; + /* * Don't do VOP_POLL for an already cached fd with * same poll events. |