| Message ID | 20210607145236.31852-1-jack@suse.cz (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | fs: Hole punch vs page cache filling races | expand |
On Mon, Jun 07, 2021 at 04:52:11PM +0200, Jan Kara wrote: > inode->i_mutex has been replaced with inode->i_rwsem long ago. Fix > comments still mentioning i_mutex. > > Reviewed-by: Christoph Hellwig <hch@lst.de> > Acked-by: Hugh Dickins <hughd@google.com> > Signed-off-by: Jan Kara <jack@suse.cz> Looks good to me, Reviewed-by: Darrick J. Wong <djwong@kernel.org> --D > --- > mm/filemap.c | 10 +++++----- > mm/madvise.c | 2 +- > mm/memory-failure.c | 2 +- > mm/rmap.c | 6 +++--- > mm/shmem.c | 20 ++++++++++---------- > mm/truncate.c | 8 ++++---- > 6 files changed, 24 insertions(+), 24 deletions(-) > > diff --git a/mm/filemap.c b/mm/filemap.c > index 66f7e9fdfbc4..ba1068a1837f 100644 > --- a/mm/filemap.c > +++ b/mm/filemap.c > @@ -76,7 +76,7 @@ > * ->swap_lock (exclusive_swap_page, others) > * ->i_pages lock > * > - * ->i_mutex > + * ->i_rwsem > * ->i_mmap_rwsem (truncate->unmap_mapping_range) > * > * ->mmap_lock > @@ -87,7 +87,7 @@ > * ->mmap_lock > * ->lock_page (access_process_vm) > * > - * ->i_mutex (generic_perform_write) > + * ->i_rwsem (generic_perform_write) > * ->mmap_lock (fault_in_pages_readable->do_page_fault) > * > * bdi->wb.list_lock > @@ -3710,12 +3710,12 @@ EXPORT_SYMBOL(generic_perform_write); > * modification times and calls proper subroutines depending on whether we > * do direct IO or a standard buffered write. > * > - * It expects i_mutex to be grabbed unless we work on a block device or similar > + * It expects i_rwsem to be grabbed unless we work on a block device or similar > * object which does not need locking at all. > * > * This function does *not* take care of syncing data in case of O_SYNC write. > * A caller has to handle it. This is mainly due to the fact that we want to > - * avoid syncing under i_mutex. > + * avoid syncing under i_rwsem. > * > * Return: > * * number of bytes written, even for truncated writes > @@ -3803,7 +3803,7 @@ EXPORT_SYMBOL(__generic_file_write_iter); > * > * This is a wrapper around __generic_file_write_iter() to be used by most > * filesystems. It takes care of syncing the file in case of O_SYNC file > - * and acquires i_mutex as needed. > + * and acquires i_rwsem as needed. > * Return: > * * negative error code if no data has been written at all of > * vfs_fsync_range() failed for a synchronous write > diff --git a/mm/madvise.c b/mm/madvise.c > index 63e489e5bfdb..a0137706b92a 100644 > --- a/mm/madvise.c > +++ b/mm/madvise.c > @@ -853,7 +853,7 @@ static long madvise_remove(struct vm_area_struct *vma, > + ((loff_t)vma->vm_pgoff << PAGE_SHIFT); > > /* > - * Filesystem's fallocate may need to take i_mutex. We need to > + * Filesystem's fallocate may need to take i_rwsem. We need to > * explicitly grab a reference because the vma (and hence the > * vma's reference to the file) can go away as soon as we drop > * mmap_lock. > diff --git a/mm/memory-failure.c b/mm/memory-failure.c > index 85ad98c00fd9..9dcc9bcea731 100644 > --- a/mm/memory-failure.c > +++ b/mm/memory-failure.c > @@ -704,7 +704,7 @@ static int me_pagecache_clean(struct page *p, unsigned long pfn) > /* > * Truncation is a bit tricky. Enable it per file system for now. > * > - * Open: to take i_mutex or not for this? Right now we don't. > + * Open: to take i_rwsem or not for this? Right now we don't. > */ > return truncate_error_page(p, pfn, mapping); > } > diff --git a/mm/rmap.c b/mm/rmap.c > index 693a610e181d..a35cbbbded0d 100644 > --- a/mm/rmap.c > +++ b/mm/rmap.c > @@ -20,9 +20,9 @@ > /* > * Lock ordering in mm: > * > - * inode->i_mutex (while writing or truncating, not reading or faulting) > + * inode->i_rwsem (while writing or truncating, not reading or faulting) > * mm->mmap_lock > - * page->flags PG_locked (lock_page) * (see huegtlbfs below) > + * page->flags PG_locked (lock_page) * (see hugetlbfs below) > * hugetlbfs_i_mmap_rwsem_key (in huge_pmd_share) > * mapping->i_mmap_rwsem > * hugetlb_fault_mutex (hugetlbfs specific page fault mutex) > @@ -41,7 +41,7 @@ > * in arch-dependent flush_dcache_mmap_lock, > * within bdi.wb->list_lock in __sync_single_inode) > * > - * anon_vma->rwsem,mapping->i_mutex (memory_failure, collect_procs_anon) > + * anon_vma->rwsem,mapping->i_mmap_rwsem (memory_failure, collect_procs_anon) > * ->tasklist_lock > * pte map lock > * > diff --git a/mm/shmem.c b/mm/shmem.c > index a08cedefbfaa..056204b1f76a 100644 > --- a/mm/shmem.c > +++ b/mm/shmem.c > @@ -96,7 +96,7 @@ static struct vfsmount *shm_mnt; > > /* > * shmem_fallocate communicates with shmem_fault or shmem_writepage via > - * inode->i_private (with i_mutex making sure that it has only one user at > + * inode->i_private (with i_rwsem making sure that it has only one user at > * a time): we would prefer not to enlarge the shmem inode just for that. > */ > struct shmem_falloc { > @@ -774,7 +774,7 @@ static int shmem_free_swap(struct address_space *mapping, > * Determine (in bytes) how many of the shmem object's pages mapped by the > * given offsets are swapped out. > * > - * This is safe to call without i_mutex or the i_pages lock thanks to RCU, > + * This is safe to call without i_rwsem or the i_pages lock thanks to RCU, > * as long as the inode doesn't go away and racy results are not a problem. > */ > unsigned long shmem_partial_swap_usage(struct address_space *mapping, > @@ -806,7 +806,7 @@ unsigned long shmem_partial_swap_usage(struct address_space *mapping, > * Determine (in bytes) how many of the shmem object's pages mapped by the > * given vma is swapped out. > * > - * This is safe to call without i_mutex or the i_pages lock thanks to RCU, > + * This is safe to call without i_rwsem or the i_pages lock thanks to RCU, > * as long as the inode doesn't go away and racy results are not a problem. > */ > unsigned long shmem_swap_usage(struct vm_area_struct *vma) > @@ -1069,7 +1069,7 @@ static int shmem_setattr(struct user_namespace *mnt_userns, > loff_t oldsize = inode->i_size; > loff_t newsize = attr->ia_size; > > - /* protected by i_mutex */ > + /* protected by i_rwsem */ > if ((newsize < oldsize && (info->seals & F_SEAL_SHRINK)) || > (newsize > oldsize && (info->seals & F_SEAL_GROW))) > return -EPERM; > @@ -2049,7 +2049,7 @@ static vm_fault_t shmem_fault(struct vm_fault *vmf) > /* > * Trinity finds that probing a hole which tmpfs is punching can > * prevent the hole-punch from ever completing: which in turn > - * locks writers out with its hold on i_mutex. So refrain from > + * locks writers out with its hold on i_rwsem. So refrain from > * faulting pages into the hole while it's being punched. Although > * shmem_undo_range() does remove the additions, it may be unable to > * keep up, as each new page needs its own unmap_mapping_range() call, > @@ -2060,7 +2060,7 @@ static vm_fault_t shmem_fault(struct vm_fault *vmf) > * we just need to make racing faults a rare case. > * > * The implementation below would be much simpler if we just used a > - * standard mutex or completion: but we cannot take i_mutex in fault, > + * standard mutex or completion: but we cannot take i_rwsem in fault, > * and bloating every shmem inode for this unlikely case would be sad. > */ > if (unlikely(inode->i_private)) { > @@ -2518,7 +2518,7 @@ shmem_write_begin(struct file *file, struct address_space *mapping, > struct shmem_inode_info *info = SHMEM_I(inode); > pgoff_t index = pos >> PAGE_SHIFT; > > - /* i_mutex is held by caller */ > + /* i_rwsem is held by caller */ > if (unlikely(info->seals & (F_SEAL_GROW | > F_SEAL_WRITE | F_SEAL_FUTURE_WRITE))) { > if (info->seals & (F_SEAL_WRITE | F_SEAL_FUTURE_WRITE)) > @@ -2618,7 +2618,7 @@ static ssize_t shmem_file_read_iter(struct kiocb *iocb, struct iov_iter *to) > > /* > * We must evaluate after, since reads (unlike writes) > - * are called without i_mutex protection against truncate > + * are called without i_rwsem protection against truncate > */ > nr = PAGE_SIZE; > i_size = i_size_read(inode); > @@ -2688,7 +2688,7 @@ static loff_t shmem_file_llseek(struct file *file, loff_t offset, int whence) > return -ENXIO; > > inode_lock(inode); > - /* We're holding i_mutex so we can access i_size directly */ > + /* We're holding i_rwsem so we can access i_size directly */ > offset = mapping_seek_hole_data(mapping, offset, inode->i_size, whence); > if (offset >= 0) > offset = vfs_setpos(file, offset, MAX_LFS_FILESIZE); > @@ -2717,7 +2717,7 @@ static long shmem_fallocate(struct file *file, int mode, loff_t offset, > loff_t unmap_end = round_down(offset + len, PAGE_SIZE) - 1; > DECLARE_WAIT_QUEUE_HEAD_ONSTACK(shmem_falloc_waitq); > > - /* protected by i_mutex */ > + /* protected by i_rwsem */ > if (info->seals & (F_SEAL_WRITE | F_SEAL_FUTURE_WRITE)) { > error = -EPERM; > goto out; > diff --git a/mm/truncate.c b/mm/truncate.c > index 95af244b112a..57a618c4a0d6 100644 > --- a/mm/truncate.c > +++ b/mm/truncate.c > @@ -415,7 +415,7 @@ EXPORT_SYMBOL(truncate_inode_pages_range); > * @mapping: mapping to truncate > * @lstart: offset from which to truncate > * > - * Called under (and serialised by) inode->i_mutex. > + * Called under (and serialised by) inode->i_rwsem. > * > * Note: When this function returns, there can be a page in the process of > * deletion (inside __delete_from_page_cache()) in the specified range. Thus > @@ -432,7 +432,7 @@ EXPORT_SYMBOL(truncate_inode_pages); > * truncate_inode_pages_final - truncate *all* pages before inode dies > * @mapping: mapping to truncate > * > - * Called under (and serialized by) inode->i_mutex. > + * Called under (and serialized by) inode->i_rwsem. > * > * Filesystems have to use this in the .evict_inode path to inform the > * VM that this is the final truncate and the inode is going away. > @@ -753,7 +753,7 @@ EXPORT_SYMBOL(truncate_pagecache); > * setattr function when ATTR_SIZE is passed in. > * > * Must be called with a lock serializing truncates and writes (generally > - * i_mutex but e.g. xfs uses a different lock) and before all filesystem > + * i_rwsem but e.g. xfs uses a different lock) and before all filesystem > * specific block truncation has been performed. > */ > void truncate_setsize(struct inode *inode, loff_t newsize) > @@ -782,7 +782,7 @@ EXPORT_SYMBOL(truncate_setsize); > * > * The function must be called after i_size is updated so that page fault > * coming after we unlock the page will already see the new i_size. > - * The function must be called while we still hold i_mutex - this not only > + * The function must be called while we still hold i_rwsem - this not only > * makes sure i_size is stable but also that userspace cannot observe new > * i_size value before we are prepared to store mmap writes at new inode size. > */ > -- > 2.26.2 >
On Mon, Jun 07, 2021 at 04:52:11PM +0200, Jan Kara wrote: > inode->i_mutex has been replaced with inode->i_rwsem long ago. Fix > comments still mentioning i_mutex. > > Reviewed-by: Christoph Hellwig <hch@lst.de> > Acked-by: Hugh Dickins <hughd@google.com> > Signed-off-by: Jan Kara <jack@suse.cz> > --- ... > diff --git a/mm/rmap.c b/mm/rmap.c > index 693a610e181d..a35cbbbded0d 100644 > --- a/mm/rmap.c > +++ b/mm/rmap.c > @@ -20,9 +20,9 @@ > /* > * Lock ordering in mm: > * > - * inode->i_mutex (while writing or truncating, not reading or faulting) > + * inode->i_rwsem (while writing or truncating, not reading or faulting) > * mm->mmap_lock > - * page->flags PG_locked (lock_page) * (see huegtlbfs below) > + * page->flags PG_locked (lock_page) * (see hugetlbfs below) > * hugetlbfs_i_mmap_rwsem_key (in huge_pmd_share) > * mapping->i_mmap_rwsem > * hugetlb_fault_mutex (hugetlbfs specific page fault mutex) > @@ -41,7 +41,7 @@ > * in arch-dependent flush_dcache_mmap_lock, > * within bdi.wb->list_lock in __sync_single_inode) > * > - * anon_vma->rwsem,mapping->i_mutex (memory_failure, collect_procs_anon) > + * anon_vma->rwsem,mapping->i_mmap_rwsem (memory_failure, collect_procs_anon) This one looks a typo.
On Thu 10-06-21 17:06:41, Ming Lei wrote: > On Mon, Jun 07, 2021 at 04:52:11PM +0200, Jan Kara wrote: > > inode->i_mutex has been replaced with inode->i_rwsem long ago. Fix > > comments still mentioning i_mutex. > > > > Reviewed-by: Christoph Hellwig <hch@lst.de> > > Acked-by: Hugh Dickins <hughd@google.com> > > Signed-off-by: Jan Kara <jack@suse.cz> > > --- > > ... > > > diff --git a/mm/rmap.c b/mm/rmap.c > > index 693a610e181d..a35cbbbded0d 100644 > > --- a/mm/rmap.c > > +++ b/mm/rmap.c > > @@ -20,9 +20,9 @@ > > /* > > * Lock ordering in mm: > > * > > - * inode->i_mutex (while writing or truncating, not reading or faulting) > > + * inode->i_rwsem (while writing or truncating, not reading or faulting) > > * mm->mmap_lock > > - * page->flags PG_locked (lock_page) * (see huegtlbfs below) > > + * page->flags PG_locked (lock_page) * (see hugetlbfs below) > > * hugetlbfs_i_mmap_rwsem_key (in huge_pmd_share) > > * mapping->i_mmap_rwsem > > * hugetlb_fault_mutex (hugetlbfs specific page fault mutex) > > @@ -41,7 +41,7 @@ > > * in arch-dependent flush_dcache_mmap_lock, > > * within bdi.wb->list_lock in __sync_single_inode) > > * > > - * anon_vma->rwsem,mapping->i_mutex (memory_failure, collect_procs_anon) > > + * anon_vma->rwsem,mapping->i_mmap_rwsem (memory_failure, collect_procs_anon) > > This one looks a typo. Actually it isn't a typo. Memory failure path doesn't touch inode->i_rwsem at all. It uses mapping->i_mmap_rwsem in collect_procs_file(). So perhaps the functions listed there should be updated to (collect_procs_anon(), collect_procs_file()) but the lock name change is IMO correct. Honza
diff --git a/mm/filemap.c b/mm/filemap.c index 66f7e9fdfbc4..ba1068a1837f 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -76,7 +76,7 @@ * ->swap_lock (exclusive_swap_page, others) * ->i_pages lock * - * ->i_mutex + * ->i_rwsem * ->i_mmap_rwsem (truncate->unmap_mapping_range) * * ->mmap_lock @@ -87,7 +87,7 @@ * ->mmap_lock * ->lock_page (access_process_vm) * - * ->i_mutex (generic_perform_write) + * ->i_rwsem (generic_perform_write) * ->mmap_lock (fault_in_pages_readable->do_page_fault) * * bdi->wb.list_lock @@ -3710,12 +3710,12 @@ EXPORT_SYMBOL(generic_perform_write); * modification times and calls proper subroutines depending on whether we * do direct IO or a standard buffered write. * - * It expects i_mutex to be grabbed unless we work on a block device or similar + * It expects i_rwsem to be grabbed unless we work on a block device or similar * object which does not need locking at all. * * This function does *not* take care of syncing data in case of O_SYNC write. * A caller has to handle it. This is mainly due to the fact that we want to - * avoid syncing under i_mutex. + * avoid syncing under i_rwsem. * * Return: * * number of bytes written, even for truncated writes @@ -3803,7 +3803,7 @@ EXPORT_SYMBOL(__generic_file_write_iter); * * This is a wrapper around __generic_file_write_iter() to be used by most * filesystems. It takes care of syncing the file in case of O_SYNC file - * and acquires i_mutex as needed. + * and acquires i_rwsem as needed. * Return: * * negative error code if no data has been written at all of * vfs_fsync_range() failed for a synchronous write diff --git a/mm/madvise.c b/mm/madvise.c index 63e489e5bfdb..a0137706b92a 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -853,7 +853,7 @@ static long madvise_remove(struct vm_area_struct *vma, + ((loff_t)vma->vm_pgoff << PAGE_SHIFT); /* - * Filesystem's fallocate may need to take i_mutex. We need to + * Filesystem's fallocate may need to take i_rwsem. We need to * explicitly grab a reference because the vma (and hence the * vma's reference to the file) can go away as soon as we drop * mmap_lock. diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 85ad98c00fd9..9dcc9bcea731 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -704,7 +704,7 @@ static int me_pagecache_clean(struct page *p, unsigned long pfn) /* * Truncation is a bit tricky. Enable it per file system for now. * - * Open: to take i_mutex or not for this? Right now we don't. + * Open: to take i_rwsem or not for this? Right now we don't. */ return truncate_error_page(p, pfn, mapping); } diff --git a/mm/rmap.c b/mm/rmap.c index 693a610e181d..a35cbbbded0d 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -20,9 +20,9 @@ /* * Lock ordering in mm: * - * inode->i_mutex (while writing or truncating, not reading or faulting) + * inode->i_rwsem (while writing or truncating, not reading or faulting) * mm->mmap_lock - * page->flags PG_locked (lock_page) * (see huegtlbfs below) + * page->flags PG_locked (lock_page) * (see hugetlbfs below) * hugetlbfs_i_mmap_rwsem_key (in huge_pmd_share) * mapping->i_mmap_rwsem * hugetlb_fault_mutex (hugetlbfs specific page fault mutex) @@ -41,7 +41,7 @@ * in arch-dependent flush_dcache_mmap_lock, * within bdi.wb->list_lock in __sync_single_inode) * - * anon_vma->rwsem,mapping->i_mutex (memory_failure, collect_procs_anon) + * anon_vma->rwsem,mapping->i_mmap_rwsem (memory_failure, collect_procs_anon) * ->tasklist_lock * pte map lock * diff --git a/mm/shmem.c b/mm/shmem.c index a08cedefbfaa..056204b1f76a 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -96,7 +96,7 @@ static struct vfsmount *shm_mnt; /* * shmem_fallocate communicates with shmem_fault or shmem_writepage via - * inode->i_private (with i_mutex making sure that it has only one user at + * inode->i_private (with i_rwsem making sure that it has only one user at * a time): we would prefer not to enlarge the shmem inode just for that. */ struct shmem_falloc { @@ -774,7 +774,7 @@ static int shmem_free_swap(struct address_space *mapping, * Determine (in bytes) how many of the shmem object's pages mapped by the * given offsets are swapped out. * - * This is safe to call without i_mutex or the i_pages lock thanks to RCU, + * This is safe to call without i_rwsem or the i_pages lock thanks to RCU, * as long as the inode doesn't go away and racy results are not a problem. */ unsigned long shmem_partial_swap_usage(struct address_space *mapping, @@ -806,7 +806,7 @@ unsigned long shmem_partial_swap_usage(struct address_space *mapping, * Determine (in bytes) how many of the shmem object's pages mapped by the * given vma is swapped out. * - * This is safe to call without i_mutex or the i_pages lock thanks to RCU, + * This is safe to call without i_rwsem or the i_pages lock thanks to RCU, * as long as the inode doesn't go away and racy results are not a problem. */ unsigned long shmem_swap_usage(struct vm_area_struct *vma) @@ -1069,7 +1069,7 @@ static int shmem_setattr(struct user_namespace *mnt_userns, loff_t oldsize = inode->i_size; loff_t newsize = attr->ia_size; - /* protected by i_mutex */ + /* protected by i_rwsem */ if ((newsize < oldsize && (info->seals & F_SEAL_SHRINK)) || (newsize > oldsize && (info->seals & F_SEAL_GROW))) return -EPERM; @@ -2049,7 +2049,7 @@ static vm_fault_t shmem_fault(struct vm_fault *vmf) /* * Trinity finds that probing a hole which tmpfs is punching can * prevent the hole-punch from ever completing: which in turn - * locks writers out with its hold on i_mutex. So refrain from + * locks writers out with its hold on i_rwsem. So refrain from * faulting pages into the hole while it's being punched. Although * shmem_undo_range() does remove the additions, it may be unable to * keep up, as each new page needs its own unmap_mapping_range() call, @@ -2060,7 +2060,7 @@ static vm_fault_t shmem_fault(struct vm_fault *vmf) * we just need to make racing faults a rare case. * * The implementation below would be much simpler if we just used a - * standard mutex or completion: but we cannot take i_mutex in fault, + * standard mutex or completion: but we cannot take i_rwsem in fault, * and bloating every shmem inode for this unlikely case would be sad. */ if (unlikely(inode->i_private)) { @@ -2518,7 +2518,7 @@ shmem_write_begin(struct file *file, struct address_space *mapping, struct shmem_inode_info *info = SHMEM_I(inode); pgoff_t index = pos >> PAGE_SHIFT; - /* i_mutex is held by caller */ + /* i_rwsem is held by caller */ if (unlikely(info->seals & (F_SEAL_GROW | F_SEAL_WRITE | F_SEAL_FUTURE_WRITE))) { if (info->seals & (F_SEAL_WRITE | F_SEAL_FUTURE_WRITE)) @@ -2618,7 +2618,7 @@ static ssize_t shmem_file_read_iter(struct kiocb *iocb, struct iov_iter *to) /* * We must evaluate after, since reads (unlike writes) - * are called without i_mutex protection against truncate + * are called without i_rwsem protection against truncate */ nr = PAGE_SIZE; i_size = i_size_read(inode); @@ -2688,7 +2688,7 @@ static loff_t shmem_file_llseek(struct file *file, loff_t offset, int whence) return -ENXIO; inode_lock(inode); - /* We're holding i_mutex so we can access i_size directly */ + /* We're holding i_rwsem so we can access i_size directly */ offset = mapping_seek_hole_data(mapping, offset, inode->i_size, whence); if (offset >= 0) offset = vfs_setpos(file, offset, MAX_LFS_FILESIZE); @@ -2717,7 +2717,7 @@ static long shmem_fallocate(struct file *file, int mode, loff_t offset, loff_t unmap_end = round_down(offset + len, PAGE_SIZE) - 1; DECLARE_WAIT_QUEUE_HEAD_ONSTACK(shmem_falloc_waitq); - /* protected by i_mutex */ + /* protected by i_rwsem */ if (info->seals & (F_SEAL_WRITE | F_SEAL_FUTURE_WRITE)) { error = -EPERM; goto out; diff --git a/mm/truncate.c b/mm/truncate.c index 95af244b112a..57a618c4a0d6 100644 --- a/mm/truncate.c +++ b/mm/truncate.c @@ -415,7 +415,7 @@ EXPORT_SYMBOL(truncate_inode_pages_range); * @mapping: mapping to truncate * @lstart: offset from which to truncate * - * Called under (and serialised by) inode->i_mutex. + * Called under (and serialised by) inode->i_rwsem. * * Note: When this function returns, there can be a page in the process of * deletion (inside __delete_from_page_cache()) in the specified range. Thus @@ -432,7 +432,7 @@ EXPORT_SYMBOL(truncate_inode_pages); * truncate_inode_pages_final - truncate *all* pages before inode dies * @mapping: mapping to truncate * - * Called under (and serialized by) inode->i_mutex. + * Called under (and serialized by) inode->i_rwsem. * * Filesystems have to use this in the .evict_inode path to inform the * VM that this is the final truncate and the inode is going away. @@ -753,7 +753,7 @@ EXPORT_SYMBOL(truncate_pagecache); * setattr function when ATTR_SIZE is passed in. * * Must be called with a lock serializing truncates and writes (generally - * i_mutex but e.g. xfs uses a different lock) and before all filesystem + * i_rwsem but e.g. xfs uses a different lock) and before all filesystem * specific block truncation has been performed. */ void truncate_setsize(struct inode *inode, loff_t newsize) @@ -782,7 +782,7 @@ EXPORT_SYMBOL(truncate_setsize); * * The function must be called after i_size is updated so that page fault * coming after we unlock the page will already see the new i_size. - * The function must be called while we still hold i_mutex - this not only + * The function must be called while we still hold i_rwsem - this not only * makes sure i_size is stable but also that userspace cannot observe new * i_size value before we are prepared to store mmap writes at new inode size. */