From d0a712ceb83ebaea32d520825ee7b997f59b168f Mon Sep 17 00:00:00 2001 From: Wenwei Tao Date: Sat, 28 Nov 2015 16:49:28 +0100 Subject: lightnvm: missing nvm_lock acquire MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit To avoid race conditions, traverse dev, media manager, and target lists and also register, unregister entries to/from them, should be always under the nvm_lock control. Signed-off-by: Wenwei Tao Signed-off-by: Matias Bjørling Signed-off-by: Jens Axboe --- drivers/lightnvm/core.c | 75 +++++++++++++++++++++++++++---------------------- 1 file changed, 42 insertions(+), 33 deletions(-) diff --git a/drivers/lightnvm/core.c b/drivers/lightnvm/core.c index ea6dba5..86ce887 100644 --- a/drivers/lightnvm/core.c +++ b/drivers/lightnvm/core.c @@ -123,6 +123,26 @@ void nvm_unregister_mgr(struct nvmm_type *mt) } EXPORT_SYMBOL(nvm_unregister_mgr); +/* register with device with a supported manager */ +static int register_mgr(struct nvm_dev *dev) +{ + struct nvmm_type *mt; + int ret = 0; + + list_for_each_entry(mt, &nvm_mgrs, list) { + ret = mt->register_mgr(dev); + if (ret > 0) { + dev->mt = mt; + break; /* successfully initialized */ + } + } + + if (!ret) + pr_info("nvm: no compatible nvm manager found.\n"); + + return ret; +} + static struct nvm_dev *nvm_find_nvm_dev(const char *name) { struct nvm_dev *dev; @@ -221,7 +241,6 @@ static void nvm_free(struct nvm_dev *dev) static int nvm_init(struct nvm_dev *dev) { - struct nvmm_type *mt; int ret = -EINVAL; if (!dev->q || !dev->ops) @@ -252,21 +271,13 @@ static int nvm_init(struct nvm_dev *dev) goto err; } - /* register with device with a supported manager */ - list_for_each_entry(mt, &nvm_mgrs, list) { - ret = mt->register_mgr(dev); - if (ret < 0) - goto err; /* initialization failed */ - if (ret > 0) { - dev->mt = mt; - break; /* successfully initialized */ - } - } - - if (!ret) { - pr_info("nvm: no compatible manager found.\n"); + down_write(&nvm_lock); + ret = register_mgr(dev); + up_write(&nvm_lock); + if (ret < 0) + goto err; + if (!ret) return 0; - } pr_info("nvm: registered %s [%u/%u/%u/%u/%u/%u]\n", dev->name, dev->sec_per_pg, dev->nr_planes, @@ -337,15 +348,17 @@ EXPORT_SYMBOL(nvm_register); void nvm_unregister(char *disk_name) { - struct nvm_dev *dev = nvm_find_nvm_dev(disk_name); + struct nvm_dev *dev; + down_write(&nvm_lock); + dev = nvm_find_nvm_dev(disk_name); if (!dev) { pr_err("nvm: could not find device %s to unregister\n", disk_name); + up_write(&nvm_lock); return; } - down_write(&nvm_lock); list_del(&dev->devices); up_write(&nvm_lock); @@ -363,38 +376,30 @@ static int nvm_create_target(struct nvm_dev *dev, { struct nvm_ioctl_create_simple *s = &create->conf.s; struct request_queue *tqueue; - struct nvmm_type *mt; struct gendisk *tdisk; struct nvm_tgt_type *tt; struct nvm_target *t; void *targetdata; int ret = 0; + down_write(&nvm_lock); if (!dev->mt) { - /* register with device with a supported NVM manager */ - list_for_each_entry(mt, &nvm_mgrs, list) { - ret = mt->register_mgr(dev); - if (ret < 0) - return ret; /* initialization failed */ - if (ret > 0) { - dev->mt = mt; - break; /* successfully initialized */ - } - } - - if (!ret) { - pr_info("nvm: no compatible nvm manager found.\n"); - return -ENODEV; + ret = register_mgr(dev); + if (!ret) + ret = -ENODEV; + if (ret < 0) { + up_write(&nvm_lock); + return ret; } } tt = nvm_find_target_type(create->tgttype); if (!tt) { pr_err("nvm: target type %s not found\n", create->tgttype); + up_write(&nvm_lock); return -EINVAL; } - down_write(&nvm_lock); list_for_each_entry(t, &dev->online_targets, list) { if (!strcmp(create->tgtname, t->disk->disk_name)) { pr_err("nvm: target name already exists.\n"); @@ -478,7 +483,9 @@ static int __nvm_configure_create(struct nvm_ioctl_create *create) struct nvm_dev *dev; struct nvm_ioctl_create_simple *s; + down_write(&nvm_lock); dev = nvm_find_nvm_dev(create->dev); + up_write(&nvm_lock); if (!dev) { pr_err("nvm: device not found\n"); return -EINVAL; @@ -537,7 +544,9 @@ static int nvm_configure_show(const char *val) return -EINVAL; } + down_write(&nvm_lock); dev = nvm_find_nvm_dev(devname); + up_write(&nvm_lock); if (!dev) { pr_err("nvm: device not found\n"); return -EINVAL; -- cgit v1.1