From e0421e911c60f0a9fb3d202bd1991ca97cf24c4c Mon Sep 17 00:00:00 2001 From: mav Date: Sun, 21 Sep 2014 12:07:22 +0000 Subject: [PATCH] MFC r271794: When updating device media size use cached cdevsw pointer. Using pointer from the cdev directly is dangerous since we have no reference on it, and it may change any time. That caused panic if device has gone. While there, report capacity change only if it really changed. Approved by: re (dephij) git-svn-id: svn://svn.freebsd.org/base/stable/10@271928 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f --- sys/cam/ctl/ctl_backend_block.c | 40 ++++++++++++++++----------------- 1 file changed, 20 insertions(+), 20 deletions(-) diff --git a/sys/cam/ctl/ctl_backend_block.c b/sys/cam/ctl/ctl_backend_block.c index 55796c676..cf56f843f 100644 --- a/sys/cam/ctl/ctl_backend_block.c +++ b/sys/cam/ctl/ctl_backend_block.c @@ -2310,7 +2310,9 @@ ctl_be_block_modify_file(struct ctl_be_block_lun *be_lun, if (params->lun_size_bytes != 0) { be_lun->size_bytes = params->lun_size_bytes; } else { + vn_lock(be_lun->vn, LK_SHARED | LK_RETRY); error = VOP_GETATTR(be_lun->vn, &vattr, curthread->td_ucred); + VOP_UNLOCK(be_lun->vn, 0); if (error != 0) { snprintf(req->error_str, sizeof(req->error_str), "error calling VOP_GETATTR() for file %s", @@ -2328,24 +2330,22 @@ static int ctl_be_block_modify_dev(struct ctl_be_block_lun *be_lun, struct ctl_lun_req *req) { - struct cdev *dev; - struct cdevsw *devsw; + struct ctl_be_block_devdata *dev_data; int error; struct ctl_lun_modify_params *params; uint64_t size_bytes; params = &req->reqdata.modify; - dev = be_lun->vn->v_rdev; - devsw = dev->si_devsw; - if (!devsw->d_ioctl) { + dev_data = &be_lun->backend.dev; + if (!dev_data->csw->d_ioctl) { snprintf(req->error_str, sizeof(req->error_str), "%s: no d_ioctl for device %s!", __func__, be_lun->dev_path); return (ENODEV); } - error = devsw->d_ioctl(dev, DIOCGMEDIASIZE, + error = dev_data->csw->d_ioctl(dev_data->cdev, DIOCGMEDIASIZE, (caddr_t)&size_bytes, FREAD, curthread); if (error) { @@ -2378,6 +2378,7 @@ ctl_be_block_modify(struct ctl_be_block_softc *softc, struct ctl_lun_req *req) { struct ctl_lun_modify_params *params; struct ctl_be_block_lun *be_lun; + uint64_t oldsize; int error; params = &req->reqdata.modify; @@ -2408,28 +2409,27 @@ ctl_be_block_modify(struct ctl_be_block_softc *softc, struct ctl_lun_req *req) } } - vn_lock(be_lun->vn, LK_SHARED | LK_RETRY); - + oldsize = be_lun->size_bytes; if (be_lun->vn->v_type == VREG) error = ctl_be_block_modify_file(be_lun, req); else error = ctl_be_block_modify_dev(be_lun, req); - - VOP_UNLOCK(be_lun->vn, 0); - if (error != 0) goto bailout_error; - be_lun->size_blocks = be_lun->size_bytes >> be_lun->blocksize_shift; + if (be_lun->size_bytes != oldsize) { + be_lun->size_blocks = be_lun->size_bytes >> + be_lun->blocksize_shift; - /* - * The maximum LBA is the size - 1. - * - * XXX: Note that this field is being updated without locking, - * which might cause problems on 32-bit architectures. - */ - be_lun->ctl_be_lun.maxlba = be_lun->size_blocks - 1; - ctl_lun_capacity_changed(&be_lun->ctl_be_lun); + /* + * The maximum LBA is the size - 1. + * + * XXX: Note that this field is being updated without locking, + * which might cause problems on 32-bit architectures. + */ + be_lun->ctl_be_lun.maxlba = be_lun->size_blocks - 1; + ctl_lun_capacity_changed(&be_lun->ctl_be_lun); + } /* Tell the user the exact size we ended up using */ params->lun_size_bytes = be_lun->size_bytes; -- 2.45.2