Re: linux-next: manual merge of the vfs-brauner tree with the vfs-brauner-fixes tree

[Christian Brauner <brauner@kernel.org>]

On Wed, Mar 25, 2026 at 08:13:56AM -0700, Darrick J. Wong wrote:
> On Wed, Mar 25, 2026 at 01:29:37PM +0000, Mark Brown wrote:
> > Hi all,
> > 
> > Today's linux-next merge of the vfs-brauner tree got a conflict in:
> > 
> >   fs/iomap/bio.c
> > 
> > between commit:
> > 
> >   f621324dfb3d6 ("iomap: fix lockdep complaint when reads fail")
> > 
> > from the vfs-brauner-fixes tree and commit:
> > 
> >   e8f9cf03c9dc9 ("iomap: support ioends for buffered reads")
> > 
> > from the vfs-brauner tree.
> > 
> > I fixed it up (see below) and can carry the fix as necessary. This
> > is now fixed as far as linux-next is concerned, but any non trivial
> > conflicts should be mentioned to your upstream maintainer when your tree
> > is submitted for merging.  You may also want to consider cooperating
> > with the maintainer of the conflicting tree to minimise any particularly
> > complex conflicts.
> 
> That looks correct to me, thanks for pointing out the merge conflict. :)

Wait wait, the vfs.fixes tree is merged into the vfs.all tree which
should have the merge conflict resolution:

commit 45933bb2dca2b8a5c81cd50947b7d0f9c381c867
Merge: a61ed0d2b28c 1b63f91d1c90
Author:     Christian Brauner <brauner@kernel.org>
AuthorDate: Tue Mar 24 23:38:16 2026 +0100
Commit:     Christian Brauner <brauner@kernel.org>
CommitDate: Tue Mar 24 23:38:16 2026 +0100

    Merge branch 'vfs-7.1.integrity' into vfs.all
    
    Signed-off-by: Christian Brauner <brauner@kernel.org>
    
    # Conflicts:
    #       fs/iomap/bio.c

diff --cc fs/iomap/bio.c
index edd908183058,f989ffcaac96..4504f4633f17
--- a/fs/iomap/bio.c
+++ b/fs/iomap/bio.c
@@@ -8,66 -9,33 +9,77 @@@
  #include "internal.h"
  #include "trace.h"
  
 +static DEFINE_SPINLOCK(failed_read_lock);
 +static struct bio_list failed_read_list = BIO_EMPTY_LIST;
 +
- static void __iomap_read_end_io(struct bio *bio)
+ static u32 __iomap_read_end_io(struct bio *bio, int error)
  {
- 	int error = blk_status_to_errno(bio->bi_status);
  	struct folio_iter fi;
+ 	u32 folio_count = 0;
  
- 	bio_for_each_folio_all(fi, bio)
+ 	bio_for_each_folio_all(fi, bio) {
  		iomap_finish_folio_read(fi.folio, fi.offset, fi.length, error);
+ 		folio_count++;
+ 	}
+ 	if (bio_integrity(bio))
+ 		fs_bio_integrity_free(bio);
  	bio_put(bio);
+ 	return folio_count;
  }
  
 +static void
 +iomap_fail_reads(
 +	struct work_struct	*work)
 +{
 +	struct bio		*bio;
 +	struct bio_list		tmp = BIO_EMPTY_LIST;
 +	unsigned long		flags;
 +
 +	spin_lock_irqsave(&failed_read_lock, flags);
 +	bio_list_merge_init(&tmp, &failed_read_list);
 +	spin_unlock_irqrestore(&failed_read_lock, flags);
 +
 +	while ((bio = bio_list_pop(&tmp)) != NULL) {
- 		__iomap_read_end_io(bio);
++		__iomap_read_end_io(bio, blk_status_to_errno(bio->bi_status));
 +		cond_resched();
 +	}
 +}
 +
 +static DECLARE_WORK(failed_read_work, iomap_fail_reads);
 +
 +static void iomap_fail_buffered_read(struct bio *bio)
 +{
 +	unsigned long flags;
 +
 +	/*
 +	 * Bounce I/O errors to a workqueue to avoid nested i_lock acquisitions
 +	 * in the fserror code.  The caller no longer owns the bio reference
 +	 * after the spinlock drops.
 +	 */
 +	spin_lock_irqsave(&failed_read_lock, flags);
 +	if (bio_list_empty(&failed_read_list))
 +		WARN_ON_ONCE(!schedule_work(&failed_read_work));
 +	bio_list_add(&failed_read_list, bio);
 +	spin_unlock_irqrestore(&failed_read_lock, flags);
 +}
 +
  static void iomap_read_end_io(struct bio *bio)
  {
 -	__iomap_read_end_io(bio, blk_status_to_errno(bio->bi_status));
 +	if (bio->bi_status) {
 +		iomap_fail_buffered_read(bio);
 +		return;
 +	}
 +
- 	__iomap_read_end_io(bio);
++	__iomap_read_end_io(bio, 0);
+ }
+ 
+ u32 iomap_finish_ioend_buffered_read(struct iomap_ioend *ioend)
+ {
+ 	return __iomap_read_end_io(&ioend->io_bio, ioend->io_error);
  }
  
- static void iomap_bio_submit_read(struct iomap_read_folio_ctx *ctx)
+ static void iomap_bio_submit_read(const struct iomap_iter *iter,
+ 		struct iomap_read_folio_ctx *ctx)
  {
  	struct bio *bio = ctx->read_ctx;
  

> 
> --D
> 
> > diff --cc fs/iomap/bio.c
> > index edd908183058f,f989ffcaac96d..0000000000000
> > --- a/fs/iomap/bio.c
> > +++ b/fs/iomap/bio.c
> > @@@ -8,66 -9,33 +9,78 @@@
> >   #include "internal.h"
> >   #include "trace.h"
> >   
> >  +static DEFINE_SPINLOCK(failed_read_lock);
> >  +static struct bio_list failed_read_list = BIO_EMPTY_LIST;
> >  +
> > - static void __iomap_read_end_io(struct bio *bio)
> > + static u32 __iomap_read_end_io(struct bio *bio, int error)
> >   {
> > - 	int error = blk_status_to_errno(bio->bi_status);
> >   	struct folio_iter fi;
> > + 	u32 folio_count = 0;
> >   
> > - 	bio_for_each_folio_all(fi, bio)
> > + 	bio_for_each_folio_all(fi, bio) {
> >   		iomap_finish_folio_read(fi.folio, fi.offset, fi.length, error);
> > + 		folio_count++;
> > + 	}
> > + 	if (bio_integrity(bio))
> > + 		fs_bio_integrity_free(bio);
> >   	bio_put(bio);
> > + 	return folio_count;
> >   }
> >   
> >  +static void
> >  +iomap_fail_reads(
> >  +	struct work_struct	*work)
> >  +{
> >  +	struct bio		*bio;
> >  +	struct bio_list		tmp = BIO_EMPTY_LIST;
> >  +	unsigned long		flags;
> >  +
> >  +	spin_lock_irqsave(&failed_read_lock, flags);
> >  +	bio_list_merge_init(&tmp, &failed_read_list);
> >  +	spin_unlock_irqrestore(&failed_read_lock, flags);
> >  +
> >  +	while ((bio = bio_list_pop(&tmp)) != NULL) {
> > - 		__iomap_read_end_io(bio);
> > ++		__iomap_read_end_io(bio, blk_status_to_errno(bio->bi_status));
> >  +		cond_resched();
> >  +	}
> >  +}
> >  +
> >  +static DECLARE_WORK(failed_read_work, iomap_fail_reads);
> >  +
> >  +static void iomap_fail_buffered_read(struct bio *bio)
> >  +{
> >  +	unsigned long flags;
> >  +
> >  +	/*
> >  +	 * Bounce I/O errors to a workqueue to avoid nested i_lock acquisitions
> >  +	 * in the fserror code.  The caller no longer owns the bio reference
> >  +	 * after the spinlock drops.
> >  +	 */
> >  +	spin_lock_irqsave(&failed_read_lock, flags);
> >  +	if (bio_list_empty(&failed_read_list))
> >  +		WARN_ON_ONCE(!schedule_work(&failed_read_work));
> >  +	bio_list_add(&failed_read_list, bio);
> >  +	spin_unlock_irqrestore(&failed_read_lock, flags);
> >  +}
> >  +
> >   static void iomap_read_end_io(struct bio *bio)
> >   {
> >  -	__iomap_read_end_io(bio, blk_status_to_errno(bio->bi_status));
> >  +	if (bio->bi_status) {
> >  +		iomap_fail_buffered_read(bio);
> >  +		return;
> >  +	}
> >  +
> > - 	__iomap_read_end_io(bio);
> > ++	__iomap_read_end_io(bio, 0);
> >   }
> >   
> > - static void iomap_bio_submit_read(struct iomap_read_folio_ctx *ctx)
> > ++
> > + u32 iomap_finish_ioend_buffered_read(struct iomap_ioend *ioend)
> > + {
> > + 	return __iomap_read_end_io(&ioend->io_bio, ioend->io_error);
> > + }
> > + 
> > + static void iomap_bio_submit_read(const struct iomap_iter *iter,
> > + 		struct iomap_read_folio_ctx *ctx)
> >   {
> >   	struct bio *bio = ctx->read_ctx;
> >   
> 
>