Merge branch 'akpm' (patches from Andrew)

Merge more updates from Andrew Morton:
 "87 patches.

  Subsystems affected by this patch series: mm (pagecache and hugetlb),
  procfs, misc, MAINTAINERS, lib, checkpatch, binfmt, kallsyms, ramfs,
  init, codafs, nilfs2, hfs, crash_dump, signals, seq_file, fork,
  sysvfs, kcov, gdb, resource, selftests, and ipc"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (87 commits)
  ipc/ipc_sysctl.c: remove fallback for !CONFIG_PROC_SYSCTL
  ipc: check checkpoint_restore_ns_capable() to modify C/R proc files
  selftests/kselftest/runner/run_one(): allow running non-executable files
  virtio-mem: disallow mapping virtio-mem memory via /dev/mem
  kernel/resource: disallow access to exclusive system RAM regions
  kernel/resource: clean up and optimize iomem_is_exclusive()
  scripts/gdb: handle split debug for vmlinux
  kcov: replace local_irq_save() with a local_lock_t
  kcov: avoid enable+disable interrupts if !in_task()
  kcov: allocate per-CPU memory on the relevant node
  Documentation/kcov: define `ip' in the example
  Documentation/kcov: include types.h in the example
  sysv: use BUILD_BUG_ON instead of runtime check
  kernel/fork.c: unshare(): use swap() to make code cleaner
  seq_file: fix passing wrong private data
  seq_file: move seq_escape() to a header
  signal: remove duplicate include in signal.h
  crash_dump: remove duplicate include in crash_dump.h
  crash_dump: fix boolreturn.cocci warning
  hfs/hfsplus: use WARN_ON for sanity check
  ...

57 files changed, 292 insertions, 249 deletions

diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index fa582748be41..f8c7f26f1fbb 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -156,7 +156,7 @@ static int padzero(unsigned long elf_bss)
 #define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) - (items))
 #define STACK_ROUND(sp, items) \
 	(((unsigned long) (sp - items)) &~ 15UL)
-#define STACK_ALLOC(sp, len) ({ sp -= len ; sp; })
+#define STACK_ALLOC(sp, len) (sp -= len)
 #endif
 
 #ifndef ELF_BASE_PLATFORM
@@ -1074,20 +1074,26 @@ out_free_interp:
 
 		vaddr = elf_ppnt->p_vaddr;
 		/*
-		 * If we are loading ET_EXEC or we have already performed
-		 * the ET_DYN load_addr calculations, proceed normally.
+		 * The first time through the loop, load_addr_set is false:
+		 * layout will be calculated. Once set, use MAP_FIXED since
+		 * we know we've already safely mapped the entire region with
+		 * MAP_FIXED_NOREPLACE in the once-per-binary logic following.
 		 */
-		if (elf_ex->e_type == ET_EXEC || load_addr_set) {
+		if (load_addr_set) {
 			elf_flags |= MAP_FIXED;
+		} else if (elf_ex->e_type == ET_EXEC) {
+			/*
+			 * This logic is run once for the first LOAD Program
+			 * Header for ET_EXEC binaries. No special handling
+			 * is needed.
+			 */
+			elf_flags |= MAP_FIXED_NOREPLACE;
 		} else if (elf_ex->e_type == ET_DYN) {
 			/*
 			 * This logic is run once for the first LOAD Program
 			 * Header for ET_DYN binaries to calculate the
 			 * randomization (load_bias) for all the LOAD
-			 * Program Headers, and to calculate the entire
-			 * size of the ELF mapping (total_size). (Note that
-			 * load_addr_set is set to true later once the
-			 * initial mapping is performed.)
+			 * Program Headers.
 			 *
 			 * There are effectively two types of ET_DYN
 			 * binaries: programs (i.e. PIE: ET_DYN with INTERP)
@@ -1108,7 +1114,7 @@ out_free_interp:
 			 * Therefore, programs are loaded offset from
 			 * ELF_ET_DYN_BASE and loaders are loaded into the
 			 * independently randomized mmap region (0 load_bias
-			 * without MAP_FIXED).
+			 * without MAP_FIXED nor MAP_FIXED_NOREPLACE).
 			 */
 			if (interpreter) {
 				load_bias = ELF_ET_DYN_BASE;
@@ -1117,7 +1123,7 @@ out_free_interp:
 				alignment = maximum_alignment(elf_phdata, elf_ex->e_phnum);
 				if (alignment)
 					load_bias &= ~(alignment - 1);
-				elf_flags |= MAP_FIXED;
+				elf_flags |= MAP_FIXED_NOREPLACE;
 			} else
 				load_bias = 0;
 
@@ -1129,7 +1135,14 @@ out_free_interp:
 			 * is then page aligned.
 			 */
 			load_bias = ELF_PAGESTART(load_bias - vaddr);
+		}
 
+		/*
+		 * Calculate the entire size of the ELF mapping (total_size).
+		 * (Note that load_addr_set is set to true later once the
+		 * initial mapping is performed.)
+		 */
+		if (!load_addr_set) {
 			total_size = total_mapping_size(elf_phdata,
 							elf_ex->e_phnum);
 			if (!total_size) {
diff --git a/fs/coda/cnode.c b/fs/coda/cnode.c
index 06855f6c7902..62a3d2565c26 100644
--- a/fs/coda/cnode.c
+++ b/fs/coda/cnode.c
@@ -63,9 +63,10 @@ struct inode * coda_iget(struct super_block * sb, struct CodaFid * fid,
 	struct inode *inode;
 	struct coda_inode_info *cii;
 	unsigned long hash = coda_f2i(fid);
+	umode_t inode_type = coda_inode_type(attr);
 
+retry:
 	inode = iget5_locked(sb, hash, coda_test_inode, coda_set_inode, fid);
-
 	if (!inode)
 		return ERR_PTR(-ENOMEM);
 
@@ -75,11 +76,15 @@ struct inode * coda_iget(struct super_block * sb, struct CodaFid * fid,
 		inode->i_ino = hash;
 		/* inode is locked and unique, no need to grab cii->c_lock */
 		cii->c_mapcount = 0;
+		coda_fill_inode(inode, attr);
 		unlock_new_inode(inode);
+	} else if ((inode->i_mode & S_IFMT) != inode_type) {
+		/* Inode has changed type, mark bad and grab a new one */
+		remove_inode_hash(inode);
+		coda_flag_inode(inode, C_PURGE);
+		iput(inode);
+		goto retry;
 	}
-
-	/* always replace the attributes, type might have changed */
-	coda_fill_inode(inode, attr);
 	return inode;
 }
 
diff --git a/fs/coda/coda_linux.c b/fs/coda/coda_linux.c
index 2e1a5a192074..903ca8fa4b9b 100644
--- a/fs/coda/coda_linux.c
+++ b/fs/coda/coda_linux.c
@@ -87,28 +87,27 @@ static struct coda_timespec timespec64_to_coda(struct timespec64 ts64)
 }
 
 /* utility functions below */
+umode_t coda_inode_type(struct coda_vattr *attr)
+{
+	switch (attr->va_type) {
+	case C_VREG:
+		return S_IFREG;
+	case C_VDIR:
+		return S_IFDIR;
+	case C_VLNK:
+		return S_IFLNK;
+	case C_VNON:
+	default:
+		return 0;
+	}
+}
+
 void coda_vattr_to_iattr(struct inode *inode, struct coda_vattr *attr)
 {
-        int inode_type;
-        /* inode's i_flags, i_ino are set by iget 
-           XXX: is this all we need ??
-           */
-        switch (attr->va_type) {
-        case C_VNON:
-                inode_type  = 0;
-                break;
-        case C_VREG:
-                inode_type = S_IFREG;
-                break;
-        case C_VDIR:
-                inode_type = S_IFDIR;
-                break;
-        case C_VLNK:
-                inode_type = S_IFLNK;
-                break;
-        default:
-                inode_type = 0;
-        }
+	/* inode's i_flags, i_ino are set by iget
+	 * XXX: is this all we need ??
+	 */
+	umode_t inode_type = coda_inode_type(attr);
 	inode->i_mode |= inode_type;
 
 	if (attr->va_mode != (u_short) -1)
diff --git a/fs/coda/coda_linux.h b/fs/coda/coda_linux.h
index e7b27754ce78..9be281bbcc06 100644
--- a/fs/coda/coda_linux.h
+++ b/fs/coda/coda_linux.h
@@ -53,10 +53,11 @@ int coda_getattr(struct user_namespace *, const struct path *, struct kstat *,
 		 u32, unsigned int);
 int coda_setattr(struct user_namespace *, struct dentry *, struct iattr *);
 
-/* this file:  heloers */
+/* this file:  helpers */
 char *coda_f2s(struct CodaFid *f);
 int coda_iscontrol(const char *name, size_t length);
 
+umode_t coda_inode_type(struct coda_vattr *attr);
 void coda_vattr_to_iattr(struct inode *, struct coda_vattr *);
 void coda_iattr_to_vattr(struct iattr *, struct coda_vattr *);
 unsigned short coda_flags_to_cflags(unsigned short);
@@ -83,6 +84,9 @@ static __inline__ void coda_flag_inode(struct inode *inode, int flag)
 {
 	struct coda_inode_info *cii = ITOC(inode);
 
+	if (!inode)
+		return;
+
 	spin_lock(&cii->c_lock);
 	cii->c_flags |= flag;
 	spin_unlock(&cii->c_lock);
diff --git a/fs/coda/dir.c b/fs/coda/dir.c
index d69989c1bac3..328d7a684b63 100644
--- a/fs/coda/dir.c
+++ b/fs/coda/dir.c
@@ -317,13 +317,10 @@ static int coda_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
 				coda_dir_drop_nlink(old_dir);
 				coda_dir_inc_nlink(new_dir);
 			}
-			coda_dir_update_mtime(old_dir);
-			coda_dir_update_mtime(new_dir);
 			coda_flag_inode(d_inode(new_dentry), C_VATTR);
-		} else {
-			coda_flag_inode(old_dir, C_VATTR);
-			coda_flag_inode(new_dir, C_VATTR);
 		}
+		coda_dir_update_mtime(old_dir);
+		coda_dir_update_mtime(new_dir);
 	}
 	return error;
 }
@@ -499,15 +496,20 @@ out:
  */
 static int coda_dentry_delete(const struct dentry * dentry)
 {
-	int flags;
+	struct inode *inode;
+	struct coda_inode_info *cii;
 
 	if (d_really_is_negative(dentry)) 
 		return 0;
 
-	flags = (ITOC(d_inode(dentry))->c_flags) & C_PURGE;
-	if (is_bad_inode(d_inode(dentry)) || flags) {
+	inode = d_inode(dentry);
+	if (!inode || is_bad_inode(inode))
 		return 1;
-	}
+
+	cii = ITOC(inode);
+	if (cii->c_flags & C_PURGE)
+		return 1;
+
 	return 0;
 }
 
diff --git a/fs/coda/file.c b/fs/coda/file.c
index ef5ca22bfb3e..29dd87be2fb8 100644
--- a/fs/coda/file.c
+++ b/fs/coda/file.c
@@ -8,6 +8,7 @@
  * to the Coda project. Contact Peter Braam <coda@cs.cmu.edu>.
  */
 
+#include <linux/refcount.h>
 #include <linux/types.h>
 #include <linux/kernel.h>
 #include <linux/time.h>
@@ -28,7 +29,7 @@
 #include "coda_int.h"
 
 struct coda_vm_ops {
-	atomic_t refcnt;
+	refcount_t refcnt;
 	struct file *coda_file;
 	const struct vm_operations_struct *host_vm_ops;
 	struct vm_operations_struct vm_ops;
@@ -98,7 +99,7 @@ coda_vm_open(struct vm_area_struct *vma)
 	struct coda_vm_ops *cvm_ops =
 		container_of(vma->vm_ops, struct coda_vm_ops, vm_ops);
 
-	atomic_inc(&cvm_ops->refcnt);
+	refcount_inc(&cvm_ops->refcnt);
 
 	if (cvm_ops->host_vm_ops && cvm_ops->host_vm_ops->open)
 		cvm_ops->host_vm_ops->open(vma);
@@ -113,7 +114,7 @@ coda_vm_close(struct vm_area_struct *vma)
 	if (cvm_ops->host_vm_ops && cvm_ops->host_vm_ops->close)
 		cvm_ops->host_vm_ops->close(vma);
 
-	if (atomic_dec_and_test(&cvm_ops->refcnt)) {
+	if (refcount_dec_and_test(&cvm_ops->refcnt)) {
 		vma->vm_ops = cvm_ops->host_vm_ops;
 		fput(cvm_ops->coda_file);
 		kfree(cvm_ops);
@@ -189,7 +190,7 @@ coda_file_mmap(struct file *coda_file, struct vm_area_struct *vma)
 		cvm_ops->vm_ops.open = coda_vm_open;
 		cvm_ops->vm_ops.close = coda_vm_close;
 		cvm_ops->coda_file = coda_file;
-		atomic_set(&cvm_ops->refcnt, 1);
+		refcount_set(&cvm_ops->refcnt, 1);
 
 		vma->vm_ops = &cvm_ops->vm_ops;
 	}
@@ -238,11 +239,10 @@ int coda_release(struct inode *coda_inode, struct file *coda_file)
 	struct coda_file_info *cfi;
 	struct coda_inode_info *cii;
 	struct inode *host_inode;
-	int err;
 
 	cfi = coda_ftoc(coda_file);
 
-	err = venus_close(coda_inode->i_sb, coda_i2f(coda_inode),
+	venus_close(coda_inode->i_sb, coda_i2f(coda_inode),
 			  coda_flags, coda_file->f_cred->fsuid);
 
 	host_inode = file_inode(cfi->cfi_container);
diff --git a/fs/coda/psdev.c b/fs/coda/psdev.c
index 240669f51eac..b39580ad4ce5 100644
--- a/fs/coda/psdev.c
+++ b/fs/coda/psdev.c
@@ -122,14 +122,10 @@ static ssize_t coda_psdev_write(struct file *file, const char __user *buf,
 				hdr.opcode, hdr.unique);
 		        nbytes = size;
 		}
-		dcbuf = kvmalloc(nbytes, GFP_KERNEL);
-		if (!dcbuf) {
-			retval = -ENOMEM;
-			goto out;
-		}
-		if (copy_from_user(dcbuf, buf, nbytes)) {
-			kvfree(dcbuf);
-			retval = -EFAULT;
+
+		dcbuf = vmemdup_user(buf, nbytes);
+		if (IS_ERR(dcbuf)) {
+			retval = PTR_ERR(dcbuf);
 			goto out;
 		}
 
@@ -388,7 +384,7 @@ MODULE_AUTHOR("Jan Harkes, Peter J. Braam");
 MODULE_DESCRIPTION("Coda Distributed File System VFS interface");
 MODULE_ALIAS_CHARDEV_MAJOR(CODA_PSDEV_MAJOR);
 MODULE_LICENSE("GPL");
-MODULE_VERSION("7.0");
+MODULE_VERSION("7.2");
 
 static int __init init_coda(void)
 {
diff --git a/fs/coda/upcall.c b/fs/coda/upcall.c
index eb3b1898da46..59f6cfd06f96 100644
--- a/fs/coda/upcall.c
+++ b/fs/coda/upcall.c
@@ -744,7 +744,8 @@ static int coda_upcall(struct venus_comm *vcp,
 	list_add_tail(&req->uc_chain, &vcp->vc_pending);
 	wake_up_interruptible(&vcp->vc_waitq);
 
-	if (req->uc_flags & CODA_REQ_ASYNC) {
+	/* We can return early on asynchronous requests */
+	if (outSize == NULL) {
 		mutex_unlock(&vcp->vc_mutex);
 		return 0;
 	}
diff --git a/fs/hfs/inode.c b/fs/hfs/inode.c
index 4a95a92546a0..2a5143246282 100644
--- a/fs/hfs/inode.c
+++ b/fs/hfs/inode.c
@@ -462,8 +462,7 @@ int hfs_write_inode(struct inode *inode, struct writeback_control *wbc)
 		goto out;
 
 	if (S_ISDIR(main_inode->i_mode)) {
-		if (fd.entrylength < sizeof(struct hfs_cat_dir))
-			/* panic? */;
+		WARN_ON(fd.entrylength < sizeof(struct hfs_cat_dir));
 		hfs_bnode_read(fd.bnode, &rec, fd.entryoffset,
 			   sizeof(struct hfs_cat_dir));
 		if (rec.type != HFS_CDR_DIR ||
@@ -483,8 +482,7 @@ int hfs_write_inode(struct inode *inode, struct writeback_control *wbc)
 		hfs_bnode_write(fd.bnode, &rec, fd.entryoffset,
 				sizeof(struct hfs_cat_file));
 	} else {
-		if (fd.entrylength < sizeof(struct hfs_cat_file))
-			/* panic? */;
+		WARN_ON(fd.entrylength < sizeof(struct hfs_cat_file));
 		hfs_bnode_read(fd.bnode, &rec, fd.entryoffset,
 			   sizeof(struct hfs_cat_file));
 		if (rec.type != HFS_CDR_FIL ||
diff --git a/fs/hfsplus/inode.c b/fs/hfsplus/inode.c
index 6fef67c2a9f0..d08a8d1d40a4 100644
--- a/fs/hfsplus/inode.c
+++ b/fs/hfsplus/inode.c
@@ -509,8 +509,7 @@ int hfsplus_cat_read_inode(struct inode *inode, struct hfs_find_data *fd)
 	if (type == HFSPLUS_FOLDER) {
 		struct hfsplus_cat_folder *folder = &entry.folder;
 
-		if (fd->entrylength < sizeof(struct hfsplus_cat_folder))
-			/* panic? */;
+		WARN_ON(fd->entrylength < sizeof(struct hfsplus_cat_folder));
 		hfs_bnode_read(fd->bnode, &entry, fd->entryoffset,
 					sizeof(struct hfsplus_cat_folder));
 		hfsplus_get_perms(inode, &folder->permissions, 1);
@@ -530,8 +529,7 @@ int hfsplus_cat_read_inode(struct inode *inode, struct hfs_find_data *fd)
 	} else if (type == HFSPLUS_FILE) {
 		struct hfsplus_cat_file *file = &entry.file;
 
-		if (fd->entrylength < sizeof(struct hfsplus_cat_file))
-			/* panic? */;
+		WARN_ON(fd->entrylength < sizeof(struct hfsplus_cat_file));
 		hfs_bnode_read(fd->bnode, &entry, fd->entryoffset,
 					sizeof(struct hfsplus_cat_file));
 
@@ -588,8 +586,7 @@ int hfsplus_cat_write_inode(struct inode *inode)
 	if (S_ISDIR(main_inode->i_mode)) {
 		struct hfsplus_cat_folder *folder = &entry.folder;
 
-		if (fd.entrylength < sizeof(struct hfsplus_cat_folder))
-			/* panic? */;
+		WARN_ON(fd.entrylength < sizeof(struct hfsplus_cat_folder));
 		hfs_bnode_read(fd.bnode, &entry, fd.entryoffset,
 					sizeof(struct hfsplus_cat_folder));
 		/* simple node checks? */
@@ -614,8 +611,7 @@ int hfsplus_cat_write_inode(struct inode *inode)
 	} else {
 		struct hfsplus_cat_file *file = &entry.file;
 
-		if (fd.entrylength < sizeof(struct hfsplus_cat_file))
-			/* panic? */;
+		WARN_ON(fd.entrylength < sizeof(struct hfsplus_cat_file));
 		hfs_bnode_read(fd.bnode, &entry, fd.entryoffset,
 					sizeof(struct hfsplus_cat_file));
 		hfsplus_inode_write_fork(inode, &file->data_fork);
diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index cdfb1ae78a3f..49d2e686be74 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -1446,8 +1446,8 @@ static int get_hstate_idx(int page_size_log)
  * otherwise hugetlb_reserve_pages reserves one less hugepages than intended.
  */
 struct file *hugetlb_file_setup(const char *name, size_t size,
-				vm_flags_t acctflag, struct ucounts **ucounts,
-				int creat_flags, int page_size_log)
+				vm_flags_t acctflag, int creat_flags,
+				int page_size_log)
 {
 	struct inode *inode;
 	struct vfsmount *mnt;
@@ -1458,22 +1458,19 @@ struct file *hugetlb_file_setup(const char *name, size_t size,
 	if (hstate_idx < 0)
 		return ERR_PTR(-ENODEV);
 
-	*ucounts = NULL;
 	mnt = hugetlbfs_vfsmount[hstate_idx];
 	if (!mnt)
 		return ERR_PTR(-ENOENT);
 
 	if (creat_flags == HUGETLB_SHMFS_INODE && !can_do_hugetlb_shm()) {
-		*ucounts = current_ucounts();
-		if (user_shm_lock(size, *ucounts)) {
-			task_lock(current);
-			pr_warn_once("%s (%d): Using mlock ulimits for SHM_HUGETLB is deprecated\n",
+		struct ucounts *ucounts = current_ucounts();
+
+		if (user_shm_lock(size, ucounts)) {
+			pr_warn_once("%s (%d): Using mlock ulimits for SHM_HUGETLB is obsolete\n",
 				current->comm, current->pid);
-			task_unlock(current);
-		} else {
-			*ucounts = NULL;
-			return ERR_PTR(-EPERM);
+			user_shm_unlock(size, ucounts);
 		}
+		return ERR_PTR(-EPERM);
 	}
 
 	file = ERR_PTR(-ENOSPC);
@@ -1498,10 +1495,6 @@ struct file *hugetlb_file_setup(const char *name, size_t size,
 
 	iput(inode);
 out:
-	if (*ucounts) {
-		user_shm_unlock(size, *ucounts);
-		*ucounts = NULL;
-	}
 	return file;
 }
 
diff --git a/fs/inode.c b/fs/inode.c
index 9abc88d7959c..3eba0940ffcf 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -428,11 +428,20 @@ void ihold(struct inode *inode)
 }
 EXPORT_SYMBOL(ihold);
 
-static void inode_lru_list_add(struct inode *inode)
+static void __inode_add_lru(struct inode *inode, bool rotate)
 {
+	if (inode->i_state & (I_DIRTY_ALL | I_SYNC | I_FREEING | I_WILL_FREE))
+		return;
+	if (atomic_read(&inode->i_count))
+		return;
+	if (!(inode->i_sb->s_flags & SB_ACTIVE))
+		return;
+	if (!mapping_shrinkable(&inode->i_data))
+		return;
+
 	if (list_lru_add(&inode->i_sb->s_inode_lru, &inode->i_lru))
 		this_cpu_inc(nr_unused);
-	else
+	else if (rotate)
 		inode->i_state |= I_REFERENCED;
 }
 
@@ -443,16 +452,11 @@ static void inode_lru_list_add(struct inode *inode)
  */
 void inode_add_lru(struct inode *inode)
 {
-	if (!(inode->i_state & (I_DIRTY_ALL | I_SYNC |
-				I_FREEING | I_WILL_FREE)) &&
-	    !atomic_read(&inode->i_count) && inode->i_sb->s_flags & SB_ACTIVE)
-		inode_lru_list_add(inode);
+	__inode_add_lru(inode, false);
 }
 
-
 static void inode_lru_list_del(struct inode *inode)
 {
-
 	if (list_lru_del(&inode->i_sb->s_inode_lru, &inode->i_lru))
 		this_cpu_dec(nr_unused);
 }
@@ -728,10 +732,6 @@ again:
 /*
  * Isolate the inode from the LRU in preparation for freeing it.
  *
- * Any inodes which are pinned purely because of attached pagecache have their
- * pagecache removed.  If the inode has metadata buffers attached to
- * mapping->private_list then try to remove them.
- *
  * If the inode has the I_REFERENCED flag set, then it means that it has been
  * used recently - the flag is set in iput_final(). When we encounter such an
  * inode, clear the flag and move it to the back of the LRU so it gets another
@@ -747,31 +747,39 @@ static enum lru_status inode_lru_isolate(struct list_head *item,
 	struct inode	*inode = container_of(item, struct inode, i_lru);
 
 	/*
-	 * we are inverting the lru lock/inode->i_lock here, so use a trylock.
-	 * If we fail to get the lock, just skip it.
+	 * We are inverting the lru lock/inode->i_lock here, so use a
+	 * trylock. If we fail to get the lock, just skip it.
 	 */
 	if (!spin_trylock(&inode->i_lock))
 		return LRU_SKIP;
 
 	/*
-	 * Referenced or dirty inodes are still in use. Give them another pass
-	 * through the LRU as we canot reclaim them now.
+	 * Inodes can get referenced, redirtied, or repopulated while
+	 * they're already on the LRU, and this can make them
+	 * unreclaimable for a while. Remove them lazily here; iput,
+	 * sync, or the last page cache deletion will requeue them.
 	 */
 	if (atomic_read(&inode->i_count) ||
-	    (inode->i_state & ~I_REFERENCED)) {
+	    (inode->i_state & ~I_REFERENCED) ||
+	    !mapping_shrinkable(&inode->i_data)) {
 		list_lru_isolate(lru, &inode->i_lru);
 		spin_unlock(&inode->i_lock);
 		this_cpu_dec(nr_unused);
 		return LRU_REMOVED;
 	}
 
-	/* recently referenced inodes get one more pass */
+	/* Recently referenced inodes get one more pass */
 	if (inode->i_state & I_REFERENCED) {
 		inode->i_state &= ~I_REFERENCED;
 		spin_unlock(&inode->i_lock);
 		return LRU_ROTATE;
 	}
 
+	/*
+	 * On highmem systems, mapping_shrinkable() permits dropping
+	 * page cache in order to free up struct inodes: lowmem might
+	 * be under pressure before the cache inside the highmem zone.
+	 */
 	if (inode_has_buffers(inode) || !mapping_empty(&inode->i_data)) {
 		__iget(inode);
 		spin_unlock(&inode->i_lock);
@@ -1638,7 +1646,7 @@ static void iput_final(struct inode *inode)
 	if (!drop &&
 	    !(inode->i_state & I_DONTCACHE) &&
 	    (sb->s_flags & SB_ACTIVE)) {
-		inode_add_lru(inode);
+		__inode_add_lru(inode, true);
 		spin_unlock(&inode->i_lock);
 		return;
 	}
diff --git a/fs/internal.h b/fs/internal.h
index cdd83d4899bb..7979ff8d168c 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -138,7 +138,6 @@ extern int vfs_open(const struct path *, struct file *);
  * inode.c
  */
 extern long prune_icache_sb(struct super_block *sb, struct shrink_control *sc);
-extern void inode_add_lru(struct inode *inode);
 extern int dentry_needs_remove_privs(struct dentry *dentry);
 
 /*
diff --git a/fs/nilfs2/alloc.c b/fs/nilfs2/alloc.c
index adf3bb0a8048..6ce8617b562d 100644
--- a/fs/nilfs2/alloc.c
+++ b/fs/nilfs2/alloc.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * alloc.c - NILFS dat/inode allocator
+ * NILFS dat/inode allocator
  *
  * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/alloc.h b/fs/nilfs2/alloc.h
index 0303c3968cee..b667e869ac07 100644
--- a/fs/nilfs2/alloc.h
+++ b/fs/nilfs2/alloc.h
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0+ */
 /*
- * alloc.h - persistent object (dat entry/disk inode) allocator/deallocator
+ * Persistent object (dat entry/disk inode) allocator/deallocator
  *
  * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/bmap.c b/fs/nilfs2/bmap.c
index 5900879d5693..798a2c1b38c6 100644
--- a/fs/nilfs2/bmap.c
+++ b/fs/nilfs2/bmap.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * bmap.c - NILFS block mapping.
+ * NILFS block mapping.
  *
  * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/bmap.h b/fs/nilfs2/bmap.h
index 2c63858e81c9..608168a5cb88 100644
--- a/fs/nilfs2/bmap.h
+++ b/fs/nilfs2/bmap.h
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0+ */
 /*
- * bmap.h - NILFS block mapping.
+ * NILFS block mapping.
  *
  * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/btnode.c b/fs/nilfs2/btnode.c
index 4391fd3abd8f..66bdaa2cf496 100644
--- a/fs/nilfs2/btnode.c
+++ b/fs/nilfs2/btnode.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * btnode.c - NILFS B-tree node cache
+ * NILFS B-tree node cache
  *
  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/btnode.h b/fs/nilfs2/btnode.h
index 0f88dbc9bcb3..11663650add7 100644
--- a/fs/nilfs2/btnode.h
+++ b/fs/nilfs2/btnode.h
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0+ */
 /*
- * btnode.h - NILFS B-tree node cache
+ * NILFS B-tree node cache
  *
  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/btree.c b/fs/nilfs2/btree.c
index ab9ec073330f..3594eabe1419 100644
--- a/fs/nilfs2/btree.c
+++ b/fs/nilfs2/btree.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * btree.c - NILFS B-tree.
+ * NILFS B-tree.
  *
  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/btree.h b/fs/nilfs2/btree.h
index d1421b646ce4..92868e1a48ca 100644
--- a/fs/nilfs2/btree.h
+++ b/fs/nilfs2/btree.h
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0+ */
 /*
- * btree.h - NILFS B-tree.
+ * NILFS B-tree.
  *
  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/cpfile.c b/fs/nilfs2/cpfile.c
index ce144776b4ef..9ebefb3acb0e 100644
--- a/fs/nilfs2/cpfile.c
+++ b/fs/nilfs2/cpfile.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * cpfile.c - NILFS checkpoint file.
+ * NILFS checkpoint file.
  *
  * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/cpfile.h b/fs/nilfs2/cpfile.h
index 6336222df24a..edabb2dc5756 100644
--- a/fs/nilfs2/cpfile.h
+++ b/fs/nilfs2/cpfile.h
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0+ */
 /*
- * cpfile.h - NILFS checkpoint file.
+ * NILFS checkpoint file.
  *
  * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/dat.c b/fs/nilfs2/dat.c
index 8bccdf1158fc..dc51d3b7a7bf 100644
--- a/fs/nilfs2/dat.c
+++ b/fs/nilfs2/dat.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * dat.c - NILFS disk address translation.
+ * NILFS disk address translation.
  *
  * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/dat.h b/fs/nilfs2/dat.h
index b17ee34580ae..468c82d26183 100644
--- a/fs/nilfs2/dat.h
+++ b/fs/nilfs2/dat.h
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0+ */
 /*
- * dat.h - NILFS disk address translation.
+ * NILFS disk address translation.
  *
  * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/dir.c b/fs/nilfs2/dir.c
index 81394e22d0a0..f8f4c2ff52f4 100644
--- a/fs/nilfs2/dir.c
+++ b/fs/nilfs2/dir.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * dir.c - NILFS directory entry operations
+ * NILFS directory entry operations
  *
  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/direct.c b/fs/nilfs2/direct.c
index f353101955e3..a35f2795b242 100644
--- a/fs/nilfs2/direct.c
+++ b/fs/nilfs2/direct.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * direct.c - NILFS direct block pointer.
+ * NILFS direct block pointer.
  *
  * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/direct.h b/fs/nilfs2/direct.h
index ec9a23c77994..b7ca896269af 100644
--- a/fs/nilfs2/direct.h
+++ b/fs/nilfs2/direct.h
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0+ */
 /*
- * direct.h - NILFS direct block pointer.
+ * NILFS direct block pointer.
  *
  * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/file.c b/fs/nilfs2/file.c
index 7cf765258fda..a265d391ffe9 100644
--- a/fs/nilfs2/file.c
+++ b/fs/nilfs2/file.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * file.c - NILFS regular file handling primitives including fsync().
+ * NILFS regular file handling primitives including fsync().
  *
  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/gcinode.c b/fs/nilfs2/gcinode.c
index 448320496856..a8f5315f01e3 100644
--- a/fs/nilfs2/gcinode.c
+++ b/fs/nilfs2/gcinode.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * gcinode.c - dummy inodes to buffer blocks for garbage collection
+ * Dummy inodes to buffer blocks for garbage collection
  *
  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/ifile.c b/fs/nilfs2/ifile.c
index 02727ed3a7c6..a8a4bc8490b4 100644
--- a/fs/nilfs2/ifile.c
+++ b/fs/nilfs2/ifile.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * ifile.c - NILFS inode file
+ * NILFS inode file
  *
  * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/ifile.h b/fs/nilfs2/ifile.h
index a1e1e5711a05..35c5273f4821 100644
--- a/fs/nilfs2/ifile.h
+++ b/fs/nilfs2/ifile.h
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0+ */
 /*
- * ifile.h - NILFS inode file
+ * NILFS inode file
  *
  * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c
index 2e8eb263cf0f..e3d807d5b83a 100644
--- a/fs/nilfs2/inode.c
+++ b/fs/nilfs2/inode.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * inode.c - NILFS inode operations.
+ * NILFS inode operations.
  *
  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/ioctl.c b/fs/nilfs2/ioctl.c
index 1d0583cfd970..fec194a666f4 100644
--- a/fs/nilfs2/ioctl.c
+++ b/fs/nilfs2/ioctl.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * ioctl.c - NILFS ioctl operations.
+ * NILFS ioctl operations.
  *
  * Copyright (C) 2007, 2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/mdt.c b/fs/nilfs2/mdt.c
index 97769fe4d588..4b3d33cf0041 100644
--- a/fs/nilfs2/mdt.c
+++ b/fs/nilfs2/mdt.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * mdt.c - meta data file for NILFS
+ * Meta data file for NILFS
  *
  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/mdt.h b/fs/nilfs2/mdt.h
index e77aea4bb921..8f86080a436d 100644
--- a/fs/nilfs2/mdt.h
+++ b/fs/nilfs2/mdt.h
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0+ */
 /*
- * mdt.h - NILFS meta data file prototype and definitions
+ * NILFS meta data file prototype and definitions
  *
  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/namei.c b/fs/nilfs2/namei.c
index 91eebeb0c48b..23899e0ae850 100644
--- a/fs/nilfs2/namei.c
+++ b/fs/nilfs2/namei.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * namei.c - NILFS pathname lookup operations.
+ * NILFS pathname lookup operations.
  *
  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/nilfs.h b/fs/nilfs2/nilfs.h
index 60b21b6eeac0..a7b81755c350 100644
--- a/fs/nilfs2/nilfs.h
+++ b/fs/nilfs2/nilfs.h
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0+ */
 /*
- * nilfs.h - NILFS local header file.
+ * NILFS local header file.
  *
  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/page.c b/fs/nilfs2/page.c
index 171fb5cd427f..bc3e2cd4117f 100644
--- a/fs/nilfs2/page.c
+++ b/fs/nilfs2/page.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * page.c - buffer/page management specific to NILFS
+ * Buffer/page management specific to NILFS
  *
  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/page.h b/fs/nilfs2/page.h
index 62b9bb469e92..569263b23c0c 100644
--- a/fs/nilfs2/page.h
+++ b/fs/nilfs2/page.h
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0+ */
 /*
- * page.h - buffer/page management specific to NILFS
+ * Buffer/page management specific to NILFS
  *
  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/recovery.c b/fs/nilfs2/recovery.c
index 2217f904a7cf..9e2ed76c0f25 100644
--- a/fs/nilfs2/recovery.c
+++ b/fs/nilfs2/recovery.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * recovery.c - NILFS recovery logic
+ * NILFS recovery logic
  *
  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/segbuf.c b/fs/nilfs2/segbuf.c
index 56872e93823d..43287b0d3e9b 100644
--- a/fs/nilfs2/segbuf.c
+++ b/fs/nilfs2/segbuf.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * segbuf.c - NILFS segment buffer
+ * NILFS segment buffer
  *
  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/segbuf.h b/fs/nilfs2/segbuf.h
index 9bea1bd59041..e20091ededba 100644
--- a/fs/nilfs2/segbuf.h
+++ b/fs/nilfs2/segbuf.h
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0+ */
 /*
- * segbuf.h - NILFS Segment buffer prototypes and definitions
+ * NILFS Segment buffer prototypes and definitions
  *
  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/segment.c b/fs/nilfs2/segment.c
index 686c8ee7b29c..85a853334771 100644
--- a/fs/nilfs2/segment.c
+++ b/fs/nilfs2/segment.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * segment.c - NILFS segment constructor.
+ * NILFS segment constructor.
  *
  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/segment.h b/fs/nilfs2/segment.h
index f5cf5308f3fc..1060f72ebf5a 100644
--- a/fs/nilfs2/segment.h
+++ b/fs/nilfs2/segment.h
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0+ */
 /*
- * segment.h - NILFS Segment constructor prototypes and definitions
+ * NILFS Segment constructor prototypes and definitions
  *
  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/sufile.c b/fs/nilfs2/sufile.c
index 63722475e17e..e385cca2004a 100644
--- a/fs/nilfs2/sufile.c
+++ b/fs/nilfs2/sufile.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * sufile.c - NILFS segment usage file.
+ * NILFS segment usage file.
  *
  * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/sufile.h b/fs/nilfs2/sufile.h
index c4e2c7a7add1..8e8a1a5a0402 100644
--- a/fs/nilfs2/sufile.h
+++ b/fs/nilfs2/sufile.h
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0+ */
 /*
- * sufile.h - NILFS segment usage file.
+ * NILFS segment usage file.
  *
  * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c
index 3134c0e42fd4..63e5fa74016c 100644
--- a/fs/nilfs2/super.c
+++ b/fs/nilfs2/super.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * super.c - NILFS module and super block management.
+ * NILFS module and super block management.
  *
  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/sysfs.c b/fs/nilfs2/sysfs.c
index 62f8a7ac19c8..81f35c5b5a40 100644
--- a/fs/nilfs2/sysfs.c
+++ b/fs/nilfs2/sysfs.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * sysfs.c - sysfs support implementation.
+ * Sysfs support implementation.
  *
  * Copyright (C) 2005-2014 Nippon Telegraph and Telephone Corporation.
  * Copyright (C) 2014 HGST, Inc., a Western Digital Company.
@@ -95,7 +95,7 @@ static ssize_t
 nilfs_snapshot_inodes_count_show(struct nilfs_snapshot_attr *attr,
 				 struct nilfs_root *root, char *buf)
 {
-	return snprintf(buf, PAGE_SIZE, "%llu\n",
+	return sysfs_emit(buf, "%llu\n",
 			(unsigned long long)atomic64_read(&root->inodes_count));
 }
 
@@ -103,7 +103,7 @@ static ssize_t
 nilfs_snapshot_blocks_count_show(struct nilfs_snapshot_attr *attr,
 				 struct nilfs_root *root, char *buf)
 {
-	return snprintf(buf, PAGE_SIZE, "%llu\n",
+	return sysfs_emit(buf, "%llu\n",
 			(unsigned long long)atomic64_read(&root->blocks_count));
 }
 
@@ -116,7 +116,7 @@ static ssize_t
 nilfs_snapshot_README_show(struct nilfs_snapshot_attr *attr,
 			    struct nilfs_root *root, char *buf)
 {
-	return snprintf(buf, PAGE_SIZE, snapshot_readme_str);
+	return sysfs_emit(buf, snapshot_readme_str);
 }
 
 NILFS_SNAPSHOT_RO_ATTR(inodes_count);
@@ -217,7 +217,7 @@ static ssize_t
 nilfs_mounted_snapshots_README_show(struct nilfs_mounted_snapshots_attr *attr,
 				    struct the_nilfs *nilfs, char *buf)
 {
-	return snprintf(buf, PAGE_SIZE, mounted_snapshots_readme_str);
+	return sysfs_emit(buf, mounted_snapshots_readme_str);
 }
 
 NILFS_MOUNTED_SNAPSHOTS_RO_ATTR(README);
@@ -255,7 +255,7 @@ nilfs_checkpoints_checkpoints_number_show(struct nilfs_checkpoints_attr *attr,
 
 	ncheckpoints = cpstat.cs_ncps;
 
-	return snprintf(buf, PAGE_SIZE, "%llu\n", ncheckpoints);
+	return sysfs_emit(buf, "%llu\n", ncheckpoints);
 }
 
 static ssize_t
@@ -278,7 +278,7 @@ nilfs_checkpoints_snapshots_number_show(struct nilfs_checkpoints_attr *attr,
 
 	nsnapshots = cpstat.cs_nsss;
 
-	return snprintf(buf, PAGE_SIZE, "%llu\n", nsnapshots);
+	return sysfs_emit(buf, "%llu\n", nsnapshots);
 }
 
 static ssize_t
@@ -292,7 +292,7 @@ nilfs_checkpoints_last_seg_checkpoint_show(struct nilfs_checkpoints_attr *attr,
 	last_cno = nilfs->ns_last_cno;
 	spin_unlock(&nilfs->ns_last_segment_lock);
 
-	return snprintf(buf, PAGE_SIZE, "%llu\n", last_cno);
+	return sysfs_emit(buf, "%llu\n", last_cno);
 }
 
 static ssize_t
@@ -306,7 +306,7 @@ nilfs_checkpoints_next_checkpoint_show(struct nilfs_checkpoints_attr *attr,
 	cno = nilfs->ns_cno;
 	up_read(&nilfs->ns_segctor_sem);
 
-	return snprintf(buf, PAGE_SIZE, "%llu\n", cno);
+	return sysfs_emit(buf, "%llu\n", cno);
 }
 
 static const char checkpoints_readme_str[] =
@@ -322,7 +322,7 @@ static ssize_t
 nilfs_checkpoints_README_show(struct nilfs_checkpoints_attr *attr,
 				struct the_nilfs *nilfs, char *buf)
 {
-	return snprintf(buf, PAGE_SIZE, checkpoints_readme_str);
+	return sysfs_emit(buf, checkpoints_readme_str);
 }
 
 NILFS_CHECKPOINTS_RO_ATTR(checkpoints_number);
@@ -353,7 +353,7 @@ nilfs_segments_segments_number_show(struct nilfs_segments_attr *attr,
 				     struct the_nilfs *nilfs,
 				     char *buf)
 {
-	return snprintf(buf, PAGE_SIZE, "%lu\n", nilfs->ns_nsegments);
+	return sysfs_emit(buf, "%lu\n", nilfs->ns_nsegments);
 }
 
 static ssize_t
@@ -361,7 +361,7 @@ nilfs_segments_blocks_per_segment_show(struct nilfs_segments_attr *attr,
 					struct the_nilfs *nilfs,
 					char *buf)
 {
-	return snprintf(buf, PAGE_SIZE, "%lu\n", nilfs->ns_blocks_per_segment);
+	return sysfs_emit(buf, "%lu\n", nilfs->ns_blocks_per_segment);
 }
 
 static ssize_t
@@ -375,7 +375,7 @@ nilfs_segments_clean_segments_show(struct nilfs_segments_attr *attr,
 	ncleansegs = nilfs_sufile_get_ncleansegs(nilfs->ns_sufile);
 	up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
 
-	return snprintf(buf, PAGE_SIZE, "%lu\n", ncleansegs);
+	return sysfs_emit(buf, "%lu\n", ncleansegs);
 }
 
 static ssize_t
@@ -395,7 +395,7 @@ nilfs_segments_dirty_segments_show(struct nilfs_segments_attr *attr,
 		return err;
 	}
 
-	return snprintf(buf, PAGE_SIZE, "%llu\n", sustat.ss_ndirtysegs);
+	return sysfs_emit(buf, "%llu\n", sustat.ss_ndirtysegs);
 }
 
 static const char segments_readme_str[] =
@@ -411,7 +411,7 @@ nilfs_segments_README_show(struct nilfs_segments_attr *attr,
 			    struct the_nilfs *nilfs,
 			    char *buf)
 {
-	return snprintf(buf, PAGE_SIZE, segments_readme_str);
+	return sysfs_emit(buf, segments_readme_str);
 }
 
 NILFS_SEGMENTS_RO_ATTR(segments_number);
@@ -448,7 +448,7 @@ nilfs_segctor_last_pseg_block_show(struct nilfs_segctor_attr *attr,
 	last_pseg = nilfs->ns_last_pseg;
 	spin_unlock(&nilfs->ns_last_segment_lock);
 
-	return snprintf(buf, PAGE_SIZE, "%llu\n",
+	return sysfs_emit(buf, "%llu\n",
 			(unsigned long long)last_pseg);
 }
 
@@ -463,7 +463,7 @@ nilfs_segctor_last_seg_sequence_show(struct nilfs_segctor_attr *attr,
 	last_seq = nilfs->ns_last_seq;
 	spin_unlock(&nilfs->ns_last_segment_lock);
 
-	return snprintf(buf, PAGE_SIZE, "%llu\n", last_seq);
+	return sysfs_emit(buf, "%llu\n", last_seq);
 }
 
 static ssize_t
@@ -477,7 +477,7 @@ nilfs_segctor_last_seg_checkpoint_show(struct nilfs_segctor_attr *attr,
 	last_cno = nilfs->ns_last_cno;
 	spin_unlock(&nilfs->ns_last_segment_lock);
 
-	return snprintf(buf, PAGE_SIZE, "%llu\n", last_cno);
+	return sysfs_emit(buf, "%llu\n", last_cno);
 }
 
 static ssize_t
@@ -491,7 +491,7 @@ nilfs_segctor_current_seg_sequence_show(struct nilfs_segctor_attr *attr,
 	seg_seq = nilfs->ns_seg_seq;
 	up_read(&nilfs->ns_segctor_sem);
 
-	return snprintf(buf, PAGE_SIZE, "%llu\n", seg_seq);
+	return sysfs_emit(buf, "%llu\n", seg_seq);
 }
 
 static ssize_t
@@ -505,7 +505,7 @@ nilfs_segctor_current_last_full_seg_show(struct nilfs_segctor_attr *attr,
 	segnum = nilfs->ns_segnum;
 	up_read(&nilfs->ns_segctor_sem);
 
-	return snprintf(buf, PAGE_SIZE, "%llu\n", segnum);
+	return sysfs_emit(buf, "%llu\n", segnum);
 }
 
 static ssize_t
@@ -519,7 +519,7 @@ nilfs_segctor_next_full_seg_show(struct nilfs_segctor_attr *attr,
 	nextnum = nilfs->ns_nextnum;
 	up_read(&nilfs->ns_segctor_sem);
 
-	return snprintf(buf, PAGE_SIZE, "%llu\n", nextnum);
+	return sysfs_emit(buf, "%llu\n", nextnum);
 }
 
 static ssize_t
@@ -533,7 +533,7 @@ nilfs_segctor_next_pseg_offset_show(struct nilfs_segctor_attr *attr,
 	pseg_offset = nilfs->ns_pseg_offset;
 	up_read(&nilfs->ns_segctor_sem);
 
-	return snprintf(buf, PAGE_SIZE, "%lu\n", pseg_offset);
+	return sysfs_emit(buf, "%lu\n", pseg_offset);
 }
 
 static ssize_t
@@ -547,7 +547,7 @@ nilfs_segctor_next_checkpoint_show(struct nilfs_segctor_attr *attr,
 	cno = nilfs->ns_cno;
 	up_read(&nilfs->ns_segctor_sem);
 
-	return snprintf(buf, PAGE_SIZE, "%llu\n", cno);
+	return sysfs_emit(buf, "%llu\n", cno);
 }
 
 static ssize_t
@@ -575,7 +575,7 @@ nilfs_segctor_last_seg_write_time_secs_show(struct nilfs_segctor_attr *attr,
 	ctime = nilfs->ns_ctime;
 	up_read(&nilfs->ns_segctor_sem);
 
-	return snprintf(buf, PAGE_SIZE, "%llu\n", ctime);
+	return sysfs_emit(buf, "%llu\n", ctime);
 }
 
 static ssize_t
@@ -603,7 +603,7 @@ nilfs_segctor_last_nongc_write_time_secs_show(struct nilfs_segctor_attr *attr,
 	nongc_ctime = nilfs->ns_nongc_ctime;
 	up_read(&nilfs->ns_segctor_sem);
 
-	return snprintf(buf, PAGE_SIZE, "%llu\n", nongc_ctime);
+	return sysfs_emit(buf, "%llu\n", nongc_ctime);
 }
 
 static ssize_t
@@ -617,7 +617,7 @@ nilfs_segctor_dirty_data_blocks_count_show(struct nilfs_segctor_attr *attr,
 	ndirtyblks = atomic_read(&nilfs->ns_ndirtyblks);
 	up_read(&nilfs->ns_segctor_sem);
 
-	return snprintf(buf, PAGE_SIZE, "%u\n", ndirtyblks);
+	return sysfs_emit(buf, "%u\n", ndirtyblks);
 }
 
 static const char segctor_readme_str[] =
@@ -654,7 +654,7 @@ static ssize_t
 nilfs_segctor_README_show(struct nilfs_segctor_attr *attr,
 			  struct the_nilfs *nilfs, char *buf)
 {
-	return snprintf(buf, PAGE_SIZE, segctor_readme_str);
+	return sysfs_emit(buf, segctor_readme_str);
 }
 
 NILFS_SEGCTOR_RO_ATTR(last_pseg_block);
@@ -723,7 +723,7 @@ nilfs_superblock_sb_write_time_secs_show(struct nilfs_superblock_attr *attr,
 	sbwtime = nilfs->ns_sbwtime;
 	up_read(&nilfs->ns_sem);
 
-	return snprintf(buf, PAGE_SIZE, "%llu\n", sbwtime);
+	return sysfs_emit(buf, "%llu\n", sbwtime);
 }
 
 static ssize_t
@@ -737,7 +737,7 @@ nilfs_superblock_sb_write_count_show(struct nilfs_superblock_attr *attr,
 	sbwcount = nilfs->ns_sbwcount;
 	up_read(&nilfs->ns_sem);
 
-	return snprintf(buf, PAGE_SIZE, "%u\n", sbwcount);
+	return sysfs_emit(buf, "%u\n", sbwcount);
 }
 
 static ssize_t
@@ -751,7 +751,7 @@ nilfs_superblock_sb_update_frequency_show(struct nilfs_superblock_attr *attr,
 	sb_update_freq = nilfs->ns_sb_update_freq;
 	up_read(&nilfs->ns_sem);
 
-	return snprintf(buf, PAGE_SIZE, "%u\n", sb_update_freq);
+	return sysfs_emit(buf, "%u\n", sb_update_freq);
 }
 
 static ssize_t
@@ -799,7 +799,7 @@ static ssize_t
 nilfs_superblock_README_show(struct nilfs_superblock_attr *attr,
 				struct the_nilfs *nilfs, char *buf)
 {
-	return snprintf(buf, PAGE_SIZE, sb_readme_str);
+	return sysfs_emit(buf, sb_readme_str);
 }
 
 NILFS_SUPERBLOCK_RO_ATTR(sb_write_time);
@@ -834,7 +834,7 @@ ssize_t nilfs_dev_revision_show(struct nilfs_dev_attr *attr,
 	u32 major = le32_to_cpu(sbp[0]->s_rev_level);
 	u16 minor = le16_to_cpu(sbp[0]->s_minor_rev_level);
 
-	return snprintf(buf, PAGE_SIZE, "%d.%d\n", major, minor);
+	return sysfs_emit(buf, "%d.%d\n", major, minor);
 }
 
 static
@@ -842,7 +842,7 @@ ssize_t nilfs_dev_blocksize_show(struct nilfs_dev_attr *attr,
 				 struct the_nilfs *nilfs,
 				 char *buf)
 {
-	return snprintf(buf, PAGE_SIZE, "%u\n", nilfs->ns_blocksize);
+	return sysfs_emit(buf, "%u\n", nilfs->ns_blocksize);
 }
 
 static
@@ -853,7 +853,7 @@ ssize_t nilfs_dev_device_size_show(struct nilfs_dev_attr *attr,
 	struct nilfs_super_block **sbp = nilfs->ns_sbp;
 	u64 dev_size = le64_to_cpu(sbp[0]->s_dev_size);
 
-	return snprintf(buf, PAGE_SIZE, "%llu\n", dev_size);
+	return sysfs_emit(buf, "%llu\n", dev_size);
 }
 
 static
@@ -864,7 +864,7 @@ ssize_t nilfs_dev_free_blocks_show(struct nilfs_dev_attr *attr,
 	sector_t free_blocks = 0;
 
 	nilfs_count_free_blocks(nilfs, &free_blocks);
-	return snprintf(buf, PAGE_SIZE, "%llu\n",
+	return sysfs_emit(buf, "%llu\n",
 			(unsigned long long)free_blocks);
 }
 
@@ -875,7 +875,7 @@ ssize_t nilfs_dev_uuid_show(struct nilfs_dev_attr *attr,
 {
 	struct nilfs_super_block **sbp = nilfs->ns_sbp;
 
-	return snprintf(buf, PAGE_SIZE, "%pUb\n", sbp[0]->s_uuid);
+	return sysfs_emit(buf, "%pUb\n", sbp[0]->s_uuid);
 }
 
 static
@@ -903,7 +903,7 @@ static ssize_t nilfs_dev_README_show(struct nilfs_dev_attr *attr,
 				     struct the_nilfs *nilfs,
 				     char *buf)
 {
-	return snprintf(buf, PAGE_SIZE, dev_readme_str);
+	return sysfs_emit(buf, dev_readme_str);
 }
 
 NILFS_DEV_RO_ATTR(revision);
@@ -1047,7 +1047,7 @@ void nilfs_sysfs_delete_device_group(struct the_nilfs *nilfs)
 static ssize_t nilfs_feature_revision_show(struct kobject *kobj,
 					    struct attribute *attr, char *buf)
 {
-	return snprintf(buf, PAGE_SIZE, "%d.%d\n",
+	return sysfs_emit(buf, "%d.%d\n",
 			NILFS_CURRENT_REV, NILFS_MINOR_REV);
 }
 
@@ -1060,7 +1060,7 @@ static ssize_t nilfs_feature_README_show(struct kobject *kobj,
 					 struct attribute *attr,
 					 char *buf)
 {
-	return snprintf(buf, PAGE_SIZE, features_readme_str);
+	return sysfs_emit(buf, features_readme_str);
 }
 
 NILFS_FEATURE_RO_ATTR(revision);
diff --git a/fs/nilfs2/sysfs.h b/fs/nilfs2/sysfs.h
index d001eb862dae..78a87a016928 100644
--- a/fs/nilfs2/sysfs.h
+++ b/fs/nilfs2/sysfs.h
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0+ */
 /*
- * sysfs.h - sysfs support declarations.
+ * Sysfs support declarations.
  *
  * Copyright (C) 2005-2014 Nippon Telegraph and Telephone Corporation.
  * Copyright (C) 2014 HGST, Inc., a Western Digital Company.
diff --git a/fs/nilfs2/the_nilfs.c b/fs/nilfs2/the_nilfs.c
index 1bfcb5d3ea48..dd48a8f74d57 100644
--- a/fs/nilfs2/the_nilfs.c
+++ b/fs/nilfs2/the_nilfs.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * the_nilfs.c - the_nilfs shared structure.
+ * the_nilfs shared structure.
  *
  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/nilfs2/the_nilfs.h b/fs/nilfs2/the_nilfs.h
index 987c8ab02aee..47c7dfbb7ea5 100644
--- a/fs/nilfs2/the_nilfs.h
+++ b/fs/nilfs2/the_nilfs.h
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0+ */
 /*
- * the_nilfs.h - the_nilfs shared structure.
+ * the_nilfs shared structure.
  *
  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
  *
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 1f394095eb88..13eda8de2998 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1982,19 +1982,21 @@ static int pid_revalidate(struct dentry *dentry, unsigned int flags)
 {
 	struct inode *inode;
 	struct task_struct *task;
+	int ret = 0;
 
-	if (flags & LOOKUP_RCU)
-		return -ECHILD;
-
-	inode = d_inode(dentry);
-	task = get_proc_task(inode);
+	rcu_read_lock();
+	inode = d_inode_rcu(dentry);
+	if (!inode)
+		goto out;
+	task = pid_task(proc_pid(inode), PIDTYPE_PID);
 
 	if (task) {
 		pid_update_inode(task, inode);
-		put_task_struct(task);
-		return 1;
+		ret = 1;
 	}
-	return 0;
+out:
+	rcu_read_unlock();
+	return ret;
 }
 
 static inline bool proc_inode_is_dead(struct inode *inode)
@@ -3802,7 +3804,10 @@ static int proc_task_readdir(struct file *file, struct dir_context *ctx)
 	     task = next_tid(task), ctx->pos++) {
 		char name[10 + 1];
 		unsigned int len;
+
 		tid = task_pid_nr_ns(task, ns);
+		if (!tid)
+			continue;	/* The task has just exited. */
 		len = snprintf(name, sizeof(name), "%u", tid);
 		if (!proc_fill_cache(file, ctx, name, len,
 				proc_task_instantiate, task, NULL)) {
diff --git a/fs/proc/vmcore.c b/fs/proc/vmcore.c
index cdbbf819d2d6..30a3b66f475a 100644
--- a/fs/proc/vmcore.c
+++ b/fs/proc/vmcore.c
@@ -62,46 +62,75 @@ core_param(novmcoredd, vmcoredd_disabled, bool, 0);
 /* Device Dump Size */
 static size_t vmcoredd_orig_sz;
 
-/*
- * Returns > 0 for RAM pages, 0 for non-RAM pages, < 0 on error
- * The called function has to take care of module refcounting.
- */
-static int (*oldmem_pfn_is_ram)(unsigned long pfn);
-
-int register_oldmem_pfn_is_ram(int (*fn)(unsigned long pfn))
+static DECLARE_RWSEM(vmcore_cb_rwsem);
+/* List of registered vmcore callbacks. */
+static LIST_HEAD(vmcore_cb_list);
+/* Whether we had a surprise unregistration of a callback. */
+static bool vmcore_cb_unstable;
+/* Whether the vmcore has been opened once. */
+static bool vmcore_opened;
+
+void register_vmcore_cb(struct vmcore_cb *cb)
 {
-	if (oldmem_pfn_is_ram)
-		return -EBUSY;
-	oldmem_pfn_is_ram = fn;
-	return 0;
+	down_write(&vmcore_cb_rwsem);
+	INIT_LIST_HEAD(&cb->next);
+	list_add_tail(&cb->next, &vmcore_cb_list);
+	/*
+	 * Registering a vmcore callback after the vmcore was opened is
+	 * very unusual (e.g., manual driver loading).
+	 */
+	if (vmcore_opened)
+		pr_warn_once("Unexpected vmcore callback registration\n");
+	up_write(&vmcore_cb_rwsem);
 }
-EXPORT_SYMBOL_GPL(register_oldmem_pfn_is_ram);
+EXPORT_SYMBOL_GPL(register_vmcore_cb);
 
-void unregister_oldmem_pfn_is_ram(void)
+void unregister_vmcore_cb(struct vmcore_cb *cb)
 {
-	oldmem_pfn_is_ram = NULL;
-	wmb();
+	down_write(&vmcore_cb_rwsem);
+	list_del(&cb->next);
+	/*
+	 * Unregistering a vmcore callback after the vmcore was opened is
+	 * very unusual (e.g., forced driver removal), but we cannot stop
+	 * unregistering.
+	 */
+	if (vmcore_opened) {
+		pr_warn_once("Unexpected vmcore callback unregistration\n");
+		vmcore_cb_unstable = true;
+	}
+	up_write(&vmcore_cb_rwsem);
 }
-EXPORT_SYMBOL_GPL(unregister_oldmem_pfn_is_ram);
+EXPORT_SYMBOL_GPL(unregister_vmcore_cb);
 
-static int pfn_is_ram(unsigned long pfn)
+static bool pfn_is_ram(unsigned long pfn)
 {
-	int (*fn)(unsigned long pfn);
-	/* pfn is ram unless fn() checks pagetype */
-	int ret = 1;
+	struct vmcore_cb *cb;
+	bool ret = true;
 
-	/*
-	 * Ask hypervisor if the pfn is really ram.
-	 * A ballooned page contains no data and reading from such a page
-	 * will cause high load in the hypervisor.
-	 */
-	fn = oldmem_pfn_is_ram;
-	if (fn)
-		ret = fn(pfn);
+	lockdep_assert_held_read(&vmcore_cb_rwsem);
+	if (unlikely(vmcore_cb_unstable))
+		return false;
+
+	list_for_each_entry(cb, &vmcore_cb_list, next) {
+		if (unlikely(!cb->pfn_is_ram))
+			continue;
+		ret = cb->pfn_is_ram(cb, pfn);
+		if (!ret)
+			break;
+	}
 
 	return ret;
 }
 
+static int open_vmcore(struct inode *inode, struct file *file)
+{
+	down_read(&vmcore_cb_rwsem);
+	vmcore_opened = true;
+	up_read(&vmcore_cb_rwsem);
+
+	return 0;
+}
+
 /* Reads a page from the oldmem device from given offset. */
 ssize_t read_from_oldmem(char *buf, size_t count,
 			 u64 *ppos, int userbuf,
@@ -117,6 +146,7 @@ ssize_t read_from_oldmem(char *buf, size_t count,
 	offset = (unsigned long)(*ppos % PAGE_SIZE);
 	pfn = (unsigned long)(*ppos / PAGE_SIZE);
 
+	down_read(&vmcore_cb_rwsem);
 	do {
 		if (count > (PAGE_SIZE - offset))
 			nr_bytes = PAGE_SIZE - offset;
@@ -124,7 +154,7 @@ ssize_t read_from_oldmem(char *buf, size_t count,
 			nr_bytes = count;
 
 		/* If pfn is not ram, return zeros for sparse dump files */
-		if (pfn_is_ram(pfn) == 0)
+		if (!pfn_is_ram(pfn))
 			memset(buf, 0, nr_bytes);
 		else {
 			if (encrypted)
@@ -136,8 +166,10 @@ ssize_t read_from_oldmem(char *buf, size_t count,
 				tmp = copy_oldmem_page(pfn, buf, nr_bytes,
 						       offset, userbuf);
 
-			if (tmp < 0)
+			if (tmp < 0) {
+				up_read(&vmcore_cb_rwsem);
 				return tmp;
+			}
 		}
 		*ppos += nr_bytes;
 		count -= nr_bytes;
@@ -147,6 +179,7 @@ ssize_t read_from_oldmem(char *buf, size_t count,
 		offset = 0;
 	} while (count);
 
+	up_read(&vmcore_cb_rwsem);
 	return read;
 }
 
@@ -537,14 +570,19 @@ static int vmcore_remap_oldmem_pfn(struct vm_area_struct *vma,
 			    unsigned long from, unsigned long pfn,
 			    unsigned long size, pgprot_t prot)
 {
+	int ret;
+
 	/*
 	 * Check if oldmem_pfn_is_ram was registered to avoid
 	 * looping over all pages without a reason.
 	 */
-	if (oldmem_pfn_is_ram)
-		return remap_oldmem_pfn_checked(vma, from, pfn, size, prot);
+	down_read(&vmcore_cb_rwsem);
+	if (!list_empty(&vmcore_cb_list) || vmcore_cb_unstable)
+		ret = remap_oldmem_pfn_checked(vma, from, pfn, size, prot);
 	else
-		return remap_oldmem_pfn_range(vma, from, pfn, size, prot);
+		ret = remap_oldmem_pfn_range(vma, from, pfn, size, prot);
+	up_read(&vmcore_cb_rwsem);
+	return ret;
 }
 
 static int mmap_vmcore(struct file *file, struct vm_area_struct *vma)
@@ -668,6 +706,7 @@ static int mmap_vmcore(struct file *file, struct vm_area_struct *vma)
 #endif
 
 static const struct proc_ops vmcore_proc_ops = {
+	.proc_open	= open_vmcore,
 	.proc_read	= read_vmcore,
 	.proc_lseek	= default_llseek,
 	.proc_mmap	= mmap_vmcore,
diff --git a/fs/ramfs/inode.c b/fs/ramfs/inode.c
index e2302342a67f..bc66d0173e33 100644
--- a/fs/ramfs/inode.c
+++ b/fs/ramfs/inode.c
@@ -204,17 +204,20 @@ static int ramfs_parse_param(struct fs_context *fc, struct fs_parameter *param)
 	int opt;
 
 	opt = fs_parse(fc, ramfs_fs_parameters, param, &result);
-	if (opt < 0) {
+	if (opt == -ENOPARAM) {
+		opt = vfs_parse_fs_param_source(fc, param);
+		if (opt != -ENOPARAM)
+			return opt;
 		/*
 		 * We might like to report bad mount options here;
 		 * but traditionally ramfs has ignored all mount options,
 		 * and as it is used as a !CONFIG_SHMEM simple substitute
 		 * for tmpfs, better continue to ignore other mount options.
 		 */
-		if (opt == -ENOPARAM)
-			opt = 0;
-		return opt;
+		return 0;
 	}
+	if (opt < 0)
+		return opt;
 
 	switch (opt) {
 	case Opt_mode:
diff --git a/fs/seq_file.c b/fs/seq_file.c
index 4a2cda04d3e2..f8e1f4ee87ff 100644
--- a/fs/seq_file.c
+++ b/fs/seq_file.c
@@ -383,22 +383,6 @@ void seq_escape_mem(struct seq_file *m, const char *src, size_t len,
 }
 EXPORT_SYMBOL(seq_escape_mem);
 
-/**
- *	seq_escape -	print string into buffer, escaping some characters
- *	@m:	target buffer
- *	@s:	string
- *	@esc:	set of characters that need escaping
- *
- *	Puts string into buffer, replacing each occurrence of character from
- *	@esc with usual octal escape.
- *	Use seq_has_overflowed() to check for errors.
- */
-void seq_escape(struct seq_file *m, const char *s, const char *esc)
-{
-	seq_escape_str(m, s, ESCAPE_OCTAL, esc);
-}
-EXPORT_SYMBOL(seq_escape);
-
 void seq_vprintf(struct seq_file *m, const char *f, va_list args)
 {
 	int len;
diff --git a/fs/sysv/super.c b/fs/sysv/super.c
index cc8e2ed155c8..d1def0771a40 100644
--- a/fs/sysv/super.c
+++ b/fs/sysv/super.c
@@ -474,10 +474,8 @@ static int v7_fill_super(struct super_block *sb, void *data, int silent)
 	struct sysv_sb_info *sbi;
 	struct buffer_head *bh;
 
-	if (440 != sizeof (struct v7_super_block))
-		panic("V7 FS: bad super-block size");
-	if (64 != sizeof (struct sysv_inode))
-		panic("sysv fs: bad i-node size");
+	BUILD_BUG_ON(sizeof(struct v7_super_block) != 440);
+	BUILD_BUG_ON(sizeof(struct sysv_inode) != 64);
 
 	sbi = kzalloc(sizeof(struct sysv_sb_info), GFP_KERNEL);
 	if (!sbi)