Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs updates from Al Viro:
 "All kinds of stuff this time around; some more notable parts:

   - RCU'd vfsmounts handling
   - new primitives for coredump handling
   - files_lock is gone
   - Bruce's delegations handling series
   - exportfs fixes

  plus misc stuff all over the place"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (101 commits)
  ecryptfs: ->f_op is never NULL
  locks: break delegations on any attribute modification
  locks: break delegations on link
  locks: break delegations on rename
  locks: helper functions for delegation breaking
  locks: break delegations on unlink
  namei: minor vfs_unlink cleanup
  locks: implement delegations
  locks: introduce new FL_DELEG lock flag
  vfs: take i_mutex on renamed file
  vfs: rename I_MUTEX_QUOTA now that it's not used for quotas
  vfs: don't use PARENT/CHILD lock classes for non-directories
  vfs: pull ext4's double-i_mutex-locking into common code
  exportfs: fix quadratic behavior in filehandle lookup
  exportfs: better variable name
  exportfs: move most of reconnect_path to helper function
  exportfs: eliminate unused "noprogress" counter
  exportfs: stop retrying once we race with rename/remove
  exportfs: clear DISCONNECTED on all parents sooner
  exportfs: more detailed comment for path_reconnect
  ...

1 files changed, 47 insertions, 105 deletions

diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
index c166f325a183..fe2a643ee005 100644
--- a/fs/binfmt_elf_fdpic.c
+++ b/fs/binfmt_elf_fdpic.c
@@ -111,7 +111,7 @@ static int is_elf_fdpic(struct elfhdr *hdr, struct file *file)
 		return 0;
 	if (!elf_check_arch(hdr) || !elf_check_fdpic(hdr))
 		return 0;
-	if (!file->f_op || !file->f_op->mmap)
+	if (!file->f_op->mmap)
 		return 0;
 	return 1;
 }
@@ -1267,35 +1267,17 @@ static int notesize(struct memelfnote *en)
 
 /* #define DEBUG */
 
-#define DUMP_WRITE(addr, nr, foffset)	\
-	do { if (!dump_write(file, (addr), (nr))) return 0; *foffset += (nr); } while(0)
-
-static int alignfile(struct file *file, loff_t *foffset)
-{
-	static const char buf[4] = { 0, };
-	DUMP_WRITE(buf, roundup(*foffset, 4) - *foffset, foffset);
-	return 1;
-}
-
-static int writenote(struct memelfnote *men, struct file *file,
-			loff_t *foffset)
+static int writenote(struct memelfnote *men, struct coredump_params *cprm)
 {
 	struct elf_note en;
 	en.n_namesz = strlen(men->name) + 1;
 	en.n_descsz = men->datasz;
 	en.n_type = men->type;
 
-	DUMP_WRITE(&en, sizeof(en), foffset);
-	DUMP_WRITE(men->name, en.n_namesz, foffset);
-	if (!alignfile(file, foffset))
-		return 0;
-	DUMP_WRITE(men->data, men->datasz, foffset);
-	if (!alignfile(file, foffset))
-		return 0;
-
-	return 1;
+	return dump_emit(cprm, &en, sizeof(en)) &&
+		dump_emit(cprm, men->name, en.n_namesz) && dump_align(cprm, 4) &&
+		dump_emit(cprm, men->data, men->datasz) && dump_align(cprm, 4);
 }
-#undef DUMP_WRITE
 
 static inline void fill_elf_fdpic_header(struct elfhdr *elf, int segs)
 {
@@ -1500,66 +1482,40 @@ static void fill_extnum_info(struct elfhdr *elf, struct elf_shdr *shdr4extnum,
 /*
  * dump the segments for an MMU process
  */
-#ifdef CONFIG_MMU
-static int elf_fdpic_dump_segments(struct file *file, size_t *size,
-			   unsigned long *limit, unsigned long mm_flags)
+static bool elf_fdpic_dump_segments(struct coredump_params *cprm)
 {
 	struct vm_area_struct *vma;
-	int err = 0;
 
 	for (vma = current->mm->mmap; vma; vma = vma->vm_next) {
 		unsigned long addr;
 
-		if (!maydump(vma, mm_flags))
+		if (!maydump(vma, cprm->mm_flags))
 			continue;
 
+#ifdef CONFIG_MMU
 		for (addr = vma->vm_start; addr < vma->vm_end;
 							addr += PAGE_SIZE) {
+			bool res;
 			struct page *page = get_dump_page(addr);
 			if (page) {
 				void *kaddr = kmap(page);
-				*size += PAGE_SIZE;
-				if (*size > *limit)
-					err = -EFBIG;
-				else if (!dump_write(file, kaddr, PAGE_SIZE))
-					err = -EIO;
+				res = dump_emit(cprm, kaddr, PAGE_SIZE);
 				kunmap(page);
 				page_cache_release(page);
-			} else if (!dump_seek(file, PAGE_SIZE))
-				err = -EFBIG;
-			if (err)
-				goto out;
+			} else {
+				res = dump_skip(cprm, PAGE_SIZE);
+			}
+			if (!res)
+				return false;
 		}
-	}
-out:
-	return err;
-}
-#endif
-
-/*
- * dump the segments for a NOMMU process
- */
-#ifndef CONFIG_MMU
-static int elf_fdpic_dump_segments(struct file *file, size_t *size,
-			   unsigned long *limit, unsigned long mm_flags)
-{
-	struct vm_area_struct *vma;
-
-	for (vma = current->mm->mmap; vma; vma = vma->vm_next) {
-		if (!maydump(vma, mm_flags))
-			continue;
-
-		if ((*size += PAGE_SIZE) > *limit)
-			return -EFBIG;
-
-		if (!dump_write(file, (void *) vma->vm_start,
+#else
+		if (!dump_emit(cprm, (void *) vma->vm_start,
 				vma->vm_end - vma->vm_start))
-			return -EIO;
+			return false;
+#endif
 	}
-
-	return 0;
+	return true;
 }
-#endif
 
 static size_t elf_core_vma_data_size(unsigned long mm_flags)
 {
@@ -1585,11 +1541,10 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
 	int has_dumped = 0;
 	mm_segment_t fs;
 	int segs;
-	size_t size = 0;
 	int i;
 	struct vm_area_struct *vma;
 	struct elfhdr *elf = NULL;
-	loff_t offset = 0, dataoff, foffset;
+	loff_t offset = 0, dataoff;
 	int numnote;
 	struct memelfnote *notes = NULL;
 	struct elf_prstatus *prstatus = NULL;	/* NT_PRSTATUS */
@@ -1606,6 +1561,8 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
 	struct elf_shdr *shdr4extnum = NULL;
 	Elf_Half e_phnum;
 	elf_addr_t e_shoff;
+	struct core_thread *ct;
+	struct elf_thread_status *tmp;
 
 	/*
 	 * We no longer stop all VM operations.
@@ -1641,28 +1598,23 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
 		goto cleanup;
 #endif
 
-	if (cprm->siginfo->si_signo) {
-		struct core_thread *ct;
-		struct elf_thread_status *tmp;
-
-		for (ct = current->mm->core_state->dumper.next;
-						ct; ct = ct->next) {
-			tmp = kzalloc(sizeof(*tmp), GFP_KERNEL);
-			if (!tmp)
-				goto cleanup;
+	for (ct = current->mm->core_state->dumper.next;
+					ct; ct = ct->next) {
+		tmp = kzalloc(sizeof(*tmp), GFP_KERNEL);
+		if (!tmp)
+			goto cleanup;
 
-			tmp->thread = ct->task;
-			list_add(&tmp->list, &thread_list);
-		}
+		tmp->thread = ct->task;
+		list_add(&tmp->list, &thread_list);
+	}
 
-		list_for_each(t, &thread_list) {
-			struct elf_thread_status *tmp;
-			int sz;
+	list_for_each(t, &thread_list) {
+		struct elf_thread_status *tmp;
+		int sz;
 
-			tmp = list_entry(t, struct elf_thread_status, list);
-			sz = elf_dump_thread_status(cprm->siginfo->si_signo, tmp);
-			thread_status_size += sz;
-		}
+		tmp = list_entry(t, struct elf_thread_status, list);
+		sz = elf_dump_thread_status(cprm->siginfo->si_signo, tmp);
+		thread_status_size += sz;
 	}
 
 	/* now collect the dump for the current */
@@ -1720,7 +1672,6 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
 
 	offset += sizeof(*elf);				/* Elf header */
 	offset += segs * sizeof(struct elf_phdr);	/* Program headers */
-	foffset = offset;
 
 	/* Write notes phdr entry */
 	{
@@ -1755,13 +1706,10 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
 
 	offset = dataoff;
 
-	size += sizeof(*elf);
-	if (size > cprm->limit || !dump_write(cprm->file, elf, sizeof(*elf)))
+	if (!dump_emit(cprm, elf, sizeof(*elf)))
 		goto end_coredump;
 
-	size += sizeof(*phdr4note);
-	if (size > cprm->limit
-	    || !dump_write(cprm->file, phdr4note, sizeof(*phdr4note)))
+	if (!dump_emit(cprm, phdr4note, sizeof(*phdr4note)))
 		goto end_coredump;
 
 	/* write program headers for segments dump */
@@ -1785,18 +1733,16 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
 			phdr.p_flags |= PF_X;
 		phdr.p_align = ELF_EXEC_PAGESIZE;
 
-		size += sizeof(phdr);
-		if (size > cprm->limit
-		    || !dump_write(cprm->file, &phdr, sizeof(phdr)))
+		if (!dump_emit(cprm, &phdr, sizeof(phdr)))
 			goto end_coredump;
 	}
 
-	if (!elf_core_write_extra_phdrs(cprm->file, offset, &size, cprm->limit))
+	if (!elf_core_write_extra_phdrs(cprm, offset))
 		goto end_coredump;
 
  	/* write out the notes section */
 	for (i = 0; i < numnote; i++)
-		if (!writenote(notes + i, cprm->file, &foffset))
+		if (!writenote(notes + i, cprm))
 			goto end_coredump;
 
 	/* write out the thread status notes section */
@@ -1805,25 +1751,21 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
 				list_entry(t, struct elf_thread_status, list);
 
 		for (i = 0; i < tmp->num_notes; i++)
-			if (!writenote(&tmp->notes[i], cprm->file, &foffset))
+			if (!writenote(&tmp->notes[i], cprm))
 				goto end_coredump;
 	}
 
-	if (!dump_seek(cprm->file, dataoff - foffset))
+	if (!dump_skip(cprm, dataoff - cprm->written))
 		goto end_coredump;
 
-	if (elf_fdpic_dump_segments(cprm->file, &size, &cprm->limit,
-				    cprm->mm_flags) < 0)
+	if (!elf_fdpic_dump_segments(cprm))
 		goto end_coredump;
 
-	if (!elf_core_write_extra_data(cprm->file, &size, cprm->limit))
+	if (!elf_core_write_extra_data(cprm))
 		goto end_coredump;
 
 	if (e_phnum == PN_XNUM) {
-		size += sizeof(*shdr4extnum);
-		if (size > cprm->limit
-		    || !dump_write(cprm->file, shdr4extnum,
-				   sizeof(*shdr4extnum)))
+		if (!dump_emit(cprm, shdr4extnum, sizeof(*shdr4extnum)))
 			goto end_coredump;
 	}