From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759604AbbIDNOm (ORCPT ); Fri, 4 Sep 2015 09:14:42 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:50490 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933207AbbIDNKe (ORCPT ); Fri, 4 Sep 2015 09:10:34 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: David Vrabel , Ian Campbell , Luis Henriques Subject: [PATCH 3.16.y-ckt 126/130] xen/gntdev: convert priv->lock to a mutex Date: Fri, 4 Sep 2015 14:08:34 +0100 Message-Id: <1441372118-5933-127-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1441372118-5933-1-git-send-email-luis.henriques@canonical.com> References: <1441372118-5933-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.7-ckt17 -stable review patch. If anyone has any objections, please let me know. ------------------ From: David Vrabel commit 1401c00e59ea021c575f74612fe2dbba36d6a4ee upstream. Unmapping may require sleeping and we unmap while holding priv->lock, so convert it to a mutex. Signed-off-by: David Vrabel Reviewed-by: Stefano Stabellini Cc: Ian Campbell [ luis: 3.16 prereq for: 30b03d05e074 xen/gntdevt: Fix race condition in gntdev_release() ] Signed-off-by: Luis Henriques --- drivers/xen/gntdev.c | 40 ++++++++++++++++++++-------------------- 1 file changed, 20 insertions(+), 20 deletions(-) diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c index 073b4a19a8b0..b7f028a8f542 100644 --- a/drivers/xen/gntdev.c +++ b/drivers/xen/gntdev.c @@ -67,7 +67,7 @@ struct gntdev_priv { * Only populated if populate_freeable_maps == 1 */ struct list_head freeable_maps; /* lock protects maps and freeable_maps */ - spinlock_t lock; + struct mutex lock; struct mm_struct *mm; struct mmu_notifier mn; }; @@ -216,9 +216,9 @@ static void gntdev_put_map(struct gntdev_priv *priv, struct grant_map *map) } if (populate_freeable_maps && priv) { - spin_lock(&priv->lock); + mutex_lock(&priv->lock); list_del(&map->next); - spin_unlock(&priv->lock); + mutex_unlock(&priv->lock); } if (map->pages && !use_ptemod) @@ -387,9 +387,9 @@ static void gntdev_vma_close(struct vm_area_struct *vma) * not do any unmapping, since that has been done prior to * closing the vma, but it may still iterate the unmap_ops list. */ - spin_lock(&priv->lock); + mutex_lock(&priv->lock); map->vma = NULL; - spin_unlock(&priv->lock); + mutex_unlock(&priv->lock); } vma->vm_private_data = NULL; gntdev_put_map(priv, map); @@ -433,14 +433,14 @@ static void mn_invl_range_start(struct mmu_notifier *mn, struct gntdev_priv *priv = container_of(mn, struct gntdev_priv, mn); struct grant_map *map; - spin_lock(&priv->lock); + mutex_lock(&priv->lock); list_for_each_entry(map, &priv->maps, next) { unmap_if_in_range(map, start, end); } list_for_each_entry(map, &priv->freeable_maps, next) { unmap_if_in_range(map, start, end); } - spin_unlock(&priv->lock); + mutex_unlock(&priv->lock); } static void mn_invl_page(struct mmu_notifier *mn, @@ -457,7 +457,7 @@ static void mn_release(struct mmu_notifier *mn, struct grant_map *map; int err; - spin_lock(&priv->lock); + mutex_lock(&priv->lock); list_for_each_entry(map, &priv->maps, next) { if (!map->vma) continue; @@ -476,7 +476,7 @@ static void mn_release(struct mmu_notifier *mn, err = unmap_grant_pages(map, /* offset */ 0, map->count); WARN_ON(err); } - spin_unlock(&priv->lock); + mutex_unlock(&priv->lock); } static struct mmu_notifier_ops gntdev_mmu_ops = { @@ -498,7 +498,7 @@ static int gntdev_open(struct inode *inode, struct file *flip) INIT_LIST_HEAD(&priv->maps); INIT_LIST_HEAD(&priv->freeable_maps); - spin_lock_init(&priv->lock); + mutex_init(&priv->lock); if (use_ptemod) { priv->mm = get_task_mm(current); @@ -572,10 +572,10 @@ static long gntdev_ioctl_map_grant_ref(struct gntdev_priv *priv, return -EFAULT; } - spin_lock(&priv->lock); + mutex_lock(&priv->lock); gntdev_add_map(priv, map); op.index = map->index << PAGE_SHIFT; - spin_unlock(&priv->lock); + mutex_unlock(&priv->lock); if (copy_to_user(u, &op, sizeof(op)) != 0) return -EFAULT; @@ -594,7 +594,7 @@ static long gntdev_ioctl_unmap_grant_ref(struct gntdev_priv *priv, return -EFAULT; pr_debug("priv %p, del %d+%d\n", priv, (int)op.index, (int)op.count); - spin_lock(&priv->lock); + mutex_lock(&priv->lock); map = gntdev_find_map_index(priv, op.index >> PAGE_SHIFT, op.count); if (map) { list_del(&map->next); @@ -602,7 +602,7 @@ static long gntdev_ioctl_unmap_grant_ref(struct gntdev_priv *priv, list_add_tail(&map->next, &priv->freeable_maps); err = 0; } - spin_unlock(&priv->lock); + mutex_unlock(&priv->lock); if (map) gntdev_put_map(priv, map); return err; @@ -670,7 +670,7 @@ static long gntdev_ioctl_notify(struct gntdev_priv *priv, void __user *u) out_flags = op.action; out_event = op.event_channel_port; - spin_lock(&priv->lock); + mutex_lock(&priv->lock); list_for_each_entry(map, &priv->maps, next) { uint64_t begin = map->index << PAGE_SHIFT; @@ -698,7 +698,7 @@ static long gntdev_ioctl_notify(struct gntdev_priv *priv, void __user *u) rc = 0; unlock_out: - spin_unlock(&priv->lock); + mutex_unlock(&priv->lock); /* Drop the reference to the event channel we did not save in the map */ if (out_flags & UNMAP_NOTIFY_SEND_EVENT) @@ -748,7 +748,7 @@ static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma) pr_debug("map %d+%d at %lx (pgoff %lx)\n", index, count, vma->vm_start, vma->vm_pgoff); - spin_lock(&priv->lock); + mutex_lock(&priv->lock); map = gntdev_find_map_index(priv, index, count); if (!map) goto unlock_out; @@ -783,7 +783,7 @@ static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma) map->flags |= GNTMAP_readonly; } - spin_unlock(&priv->lock); + mutex_unlock(&priv->lock); if (use_ptemod) { err = apply_to_page_range(vma->vm_mm, vma->vm_start, @@ -811,11 +811,11 @@ static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma) return 0; unlock_out: - spin_unlock(&priv->lock); + mutex_unlock(&priv->lock); return err; out_unlock_put: - spin_unlock(&priv->lock); + mutex_unlock(&priv->lock); out_put_map: if (use_ptemod) map->vma = NULL;