Merge branch 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull more set_fs removal from Al Viro:
 "Christoph's 'use kernel_read and friends rather than open-coding
  set_fs()' series"

* 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fs: unexport vfs_readv and vfs_writev
  fs: unexport vfs_read and vfs_write
  fs: unexport __vfs_read/__vfs_write
  lustre: switch to kernel_write
  gadget/f_mass_storage: stop messing with the address limit
  mconsole: switch to kernel_read
  btrfs: switch write_buf to kernel_write
  net/9p: switch p9_fd_read to kernel_write
  mm/nommu: switch do_mmap_private to kernel_read
  serial2002: switch serial2002_tty_write to kernel_{read/write}
  fs: make the buf argument to __kernel_write a void pointer
  fs: fix kernel_write prototype
  fs: fix kernel_read prototype
  fs: move kernel_read to fs/read_write.c
  fs: move kernel_write to fs/read_write.c
  autofs4: switch autofs4_write to __kernel_write
  ashmem: switch to ->read_iter

12 files changed, 78 insertions, 107 deletions

diff --git a/fs/autofs4/waitq.c b/fs/autofs4/waitq.c
index 24a58bf..4ac49d0 100644
--- a/fs/autofs4/waitq.c
+++ b/fs/autofs4/waitq.c
@@ -56,19 +56,14 @@ static int autofs4_write(struct autofs_sb_info *sbi,
 			 struct file *file, const void *addr, int bytes)
 {
 	unsigned long sigpipe, flags;
-	mm_segment_t fs;
 	const char *data = (const char *)addr;
 	ssize_t wr = 0;
 
 	sigpipe = sigismember(&current->pending.signal, SIGPIPE);
 
-	/* Save pointer to user space and point back to kernel space */
-	fs = get_fs();
-	set_fs(KERNEL_DS);
-
 	mutex_lock(&sbi->pipe_mutex);
 	while (bytes) {
-		wr = __vfs_write(file, data, bytes, &file->f_pos);
+		wr = __kernel_write(file, data, bytes, &file->f_pos);
 		if (wr <= 0)
 			break;
 		data += wr;
@@ -76,8 +71,6 @@ static int autofs4_write(struct autofs_sb_info *sbi,
 	}
 	mutex_unlock(&sbi->pipe_mutex);
 
-	set_fs(fs);
-
 	/* Keep the currently executing process from receiving a
 	 * SIGPIPE unless it was already supposed to get one
 	 */
diff --git a/fs/binfmt_aout.c b/fs/binfmt_aout.c
index 9be82c4..ce1824f 100644
--- a/fs/binfmt_aout.c
+++ b/fs/binfmt_aout.c
@@ -341,11 +341,12 @@ static int load_aout_library(struct file *file)
 	unsigned long error;
 	int retval;
 	struct exec ex;
+	loff_t pos = 0;
 
 	inode = file_inode(file);
 
 	retval = -ENOEXEC;
-	error = kernel_read(file, 0, (char *) &ex, sizeof(ex));
+	error = kernel_read(file, &ex, sizeof(ex), &pos);
 	if (error != sizeof(ex))
 		goto out;
 
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index ec45d24..73b01e4 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -409,6 +409,7 @@ static struct elf_phdr *load_elf_phdrs(struct elfhdr *elf_ex,
 {
 	struct elf_phdr *elf_phdata = NULL;
 	int retval, size, err = -1;
+	loff_t pos = elf_ex->e_phoff;
 
 	/*
 	 * If the size of this structure has changed, then punt, since
@@ -432,8 +433,7 @@ static struct elf_phdr *load_elf_phdrs(struct elfhdr *elf_ex,
 		goto out;
 
 	/* Read in the program headers */
-	retval = kernel_read(elf_file, elf_ex->e_phoff,
-			     (char *)elf_phdata, size);
+	retval = kernel_read(elf_file, elf_phdata, size, &pos);
 	if (retval != size) {
 		err = (retval < 0) ? retval : -EIO;
 		goto out;
@@ -698,6 +698,7 @@ static int load_elf_binary(struct linux_binprm *bprm)
 		struct elfhdr interp_elf_ex;
 	} *loc;
 	struct arch_elf_state arch_state = INIT_ARCH_ELF_STATE;
+	loff_t pos;
 
 	loc = kmalloc(sizeof(*loc), GFP_KERNEL);
 	if (!loc) {
@@ -750,9 +751,9 @@ static int load_elf_binary(struct linux_binprm *bprm)
 			if (!elf_interpreter)
 				goto out_free_ph;
 
-			retval = kernel_read(bprm->file, elf_ppnt->p_offset,
-					     elf_interpreter,
-					     elf_ppnt->p_filesz);
+			pos = elf_ppnt->p_offset;
+			retval = kernel_read(bprm->file, elf_interpreter,
+					     elf_ppnt->p_filesz, &pos);
 			if (retval != elf_ppnt->p_filesz) {
 				if (retval >= 0)
 					retval = -EIO;
@@ -776,9 +777,9 @@ static int load_elf_binary(struct linux_binprm *bprm)
 			would_dump(bprm, interpreter);
 
 			/* Get the exec headers */
-			retval = kernel_read(interpreter, 0,
-					     (void *)&loc->interp_elf_ex,
-					     sizeof(loc->interp_elf_ex));
+			pos = 0;
+			retval = kernel_read(interpreter, &loc->interp_elf_ex,
+					     sizeof(loc->interp_elf_ex), &pos);
 			if (retval != sizeof(loc->interp_elf_ex)) {
 				if (retval >= 0)
 					retval = -EIO;
@@ -1175,9 +1176,10 @@ static int load_elf_library(struct file *file)
 	unsigned long elf_bss, bss, len;
 	int retval, error, i, j;
 	struct elfhdr elf_ex;
+	loff_t pos = 0;
 
 	error = -ENOEXEC;
-	retval = kernel_read(file, 0, (char *)&elf_ex, sizeof(elf_ex));
+	retval = kernel_read(file, &elf_ex, sizeof(elf_ex), &pos);
 	if (retval != sizeof(elf_ex))
 		goto out;
 
@@ -1201,7 +1203,8 @@ static int load_elf_library(struct file *file)
 
 	eppnt = elf_phdata;
 	error = -ENOEXEC;
-	retval = kernel_read(file, elf_ex.e_phoff, (char *)eppnt, j);
+	pos =  elf_ex.e_phoff;
+	retval = kernel_read(file, eppnt, j, &pos);
 	if (retval != j)
 		goto out_free_ph;
 
diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
index 5aa9199..e70c039 100644
--- a/fs/binfmt_elf_fdpic.c
+++ b/fs/binfmt_elf_fdpic.c
@@ -145,6 +145,7 @@ static int elf_fdpic_fetch_phdrs(struct elf_fdpic_params *params,
 	struct elf32_phdr *phdr;
 	unsigned long size;
 	int retval, loop;
+	loff_t pos = params->hdr.e_phoff;
 
 	if (params->hdr.e_phentsize != sizeof(struct elf_phdr))
 		return -ENOMEM;
@@ -156,8 +157,7 @@ static int elf_fdpic_fetch_phdrs(struct elf_fdpic_params *params,
 	if (!params->phdrs)
 		return -ENOMEM;
 
-	retval = kernel_read(file, params->hdr.e_phoff,
-			     (char *) params->phdrs, size);
+	retval = kernel_read(file, params->phdrs, size, &pos);
 	if (unlikely(retval != size))
 		return retval < 0 ? retval : -ENOEXEC;
 
@@ -199,6 +199,7 @@ static int load_elf_fdpic_binary(struct linux_binprm *bprm)
 	char *interpreter_name = NULL;
 	int executable_stack;
 	int retval, i;
+	loff_t pos;
 
 	kdebug("____ LOAD %d ____", current->pid);
 
@@ -246,10 +247,9 @@ static int load_elf_fdpic_binary(struct linux_binprm *bprm)
 			if (!interpreter_name)
 				goto error;
 
-			retval = kernel_read(bprm->file,
-					     phdr->p_offset,
-					     interpreter_name,
-					     phdr->p_filesz);
+			pos = phdr->p_offset;
+			retval = kernel_read(bprm->file, interpreter_name,
+					     phdr->p_filesz, &pos);
 			if (unlikely(retval != phdr->p_filesz)) {
 				if (retval >= 0)
 					retval = -ENOEXEC;
@@ -277,8 +277,9 @@ static int load_elf_fdpic_binary(struct linux_binprm *bprm)
 			 */
 			would_dump(bprm, interpreter);
 
-			retval = kernel_read(interpreter, 0, bprm->buf,
-					     BINPRM_BUF_SIZE);
+			pos = 0;
+			retval = kernel_read(interpreter, bprm->buf,
+					BINPRM_BUF_SIZE, &pos);
 			if (unlikely(retval != BINPRM_BUF_SIZE)) {
 				if (retval >= 0)
 					retval = -ENOEXEC;
diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c
index ce6537c..475d083 100644
--- a/fs/binfmt_flat.c
+++ b/fs/binfmt_flat.c
@@ -176,19 +176,14 @@ static int create_flat_tables(struct linux_binprm *bprm, unsigned long arg_start
 #define ENCRYPTED    0x20 /* bit 5 set: file is encrypted */
 #define RESERVED     0xC0 /* bit 6,7:   reserved */
 
-static int decompress_exec(
-	struct linux_binprm *bprm,
-	unsigned long offset,
-	char *dst,
-	long len,
-	int fd)
+static int decompress_exec(struct linux_binprm *bprm, loff_t fpos, char *dst,
+		long len, int fd)
 {
 	unsigned char *buf;
 	z_stream strm;
-	loff_t fpos;
 	int ret, retval;
 
-	pr_debug("decompress_exec(offset=%lx,buf=%p,len=%lx)\n", offset, dst, len);
+	pr_debug("decompress_exec(offset=%llx,buf=%p,len=%lx)\n", fpos, dst, len);
 
 	memset(&strm, 0, sizeof(strm));
 	strm.workspace = kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL);
@@ -202,13 +197,11 @@ static int decompress_exec(
 	}
 
 	/* Read in first chunk of data and parse gzip header. */
-	fpos = offset;
-	ret = kernel_read(bprm->file, offset, buf, LBUFSIZE);
+	ret = kernel_read(bprm->file, buf, LBUFSIZE, &fpos);
 
 	strm.next_in = buf;
 	strm.avail_in = ret;
 	strm.total_in = 0;
-	fpos += ret;
 
 	retval = -ENOEXEC;
 
@@ -274,7 +267,7 @@ static int decompress_exec(
 	}
 
 	while ((ret = zlib_inflate(&strm, Z_NO_FLUSH)) == Z_OK) {
-		ret = kernel_read(bprm->file, fpos, buf, LBUFSIZE);
+		ret = kernel_read(bprm->file, buf, LBUFSIZE, &fpos);
 		if (ret <= 0)
 			break;
 		len -= ret;
@@ -282,7 +275,6 @@ static int decompress_exec(
 		strm.next_in = buf;
 		strm.avail_in = ret;
 		strm.total_in = 0;
-		fpos += ret;
 	}
 
 	if (ret < 0) {
diff --git a/fs/binfmt_misc.c b/fs/binfmt_misc.c
index f471809..ce7181e 100644
--- a/fs/binfmt_misc.c
+++ b/fs/binfmt_misc.c
@@ -218,12 +218,15 @@ static int load_misc_binary(struct linux_binprm *bprm)
 
 	bprm->file = interp_file;
 	if (fmt->flags & MISC_FMT_CREDENTIALS) {
+		loff_t pos = 0;
+
 		/*
 		 * No need to call prepare_binprm(), it's already been
 		 * done.  bprm->buf is stale, update from interp_file.
 		 */
 		memset(bprm->buf, 0, BINPRM_BUF_SIZE);
-		retval = kernel_read(bprm->file, 0, bprm->buf, BINPRM_BUF_SIZE);
+		retval = kernel_read(bprm->file, bprm->buf, BINPRM_BUF_SIZE,
+				&pos);
 	} else
 		retval = prepare_binprm(bprm);
 
diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
index 8f1d3d6..32b043e 100644
--- a/fs/btrfs/send.c
+++ b/fs/btrfs/send.c
@@ -539,33 +539,23 @@ static struct btrfs_path *alloc_path_for_send(void)
 static int write_buf(struct file *filp, const void *buf, u32 len, loff_t *off)
 {
 	int ret;
-	mm_segment_t old_fs;
 	u32 pos = 0;
 
-	old_fs = get_fs();
-	set_fs(KERNEL_DS);
-
 	while (pos < len) {
-		ret = vfs_write(filp, (__force const char __user *)buf + pos,
-				len - pos, off);
+		ret = kernel_write(filp, buf + pos, len - pos, off);
 		/* TODO handle that correctly */
 		/*if (ret == -ERESTARTSYS) {
 			continue;
 		}*/
 		if (ret < 0)
-			goto out;
+			return ret;
 		if (ret == 0) {
-			ret = -EIO;
-			goto out;
+			return -EIO;
 		}
 		pos += ret;
 	}
 
-	ret = 0;
-
-out:
-	set_fs(old_fs);
-	return ret;
+	return 0;
 }
 
 static int tlv_put(struct send_ctx *sctx, u16 attr, const void *data, int len)
diff --git a/fs/coda/dir.c b/fs/coda/dir.c
index c0474ac..274ab55 100644
--- a/fs/coda/dir.c
+++ b/fs/coda/dir.c
@@ -368,9 +368,10 @@ static int coda_venus_readdir(struct file *coda_file, struct dir_context *ctx)
 		goto out;
 
 	while (1) {
+		loff_t pos = ctx->pos - 2;
+
 		/* read entries from the directory file */
-		ret = kernel_read(host_file, ctx->pos - 2, (char *)vdir,
-				  sizeof(*vdir));
+		ret = kernel_read(host_file, vdir, sizeof(*vdir), &pos);
 		if (ret < 0) {
 			pr_err("%s: read dir %s failed %d\n",
 			       __func__, coda_f2s(&cii->c_fid), ret);
diff --git a/fs/ecryptfs/read_write.c b/fs/ecryptfs/read_write.c
index 039e627..c596e7c 100644
--- a/fs/ecryptfs/read_write.c
+++ b/fs/ecryptfs/read_write.c
@@ -47,7 +47,7 @@ int ecryptfs_write_lower(struct inode *ecryptfs_inode, char *data,
 	lower_file = ecryptfs_inode_to_private(ecryptfs_inode)->lower_file;
 	if (!lower_file)
 		return -EIO;
-	rc = kernel_write(lower_file, data, size, offset);
+	rc = kernel_write(lower_file, data, size, &offset);
 	mark_inode_dirty_sync(ecryptfs_inode);
 	return rc;
 }
@@ -237,7 +237,7 @@ int ecryptfs_read_lower(char *data, loff_t offset, size_t size,
 	lower_file = ecryptfs_inode_to_private(ecryptfs_inode)->lower_file;
 	if (!lower_file)
 		return -EIO;
-	return kernel_read(lower_file, offset, data, size);
+	return kernel_read(lower_file, data, size, &offset);
 }
 
 /**
diff --git a/fs/exec.c b/fs/exec.c
index daa19d8..69a5432 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -885,23 +885,6 @@ struct file *open_exec(const char *name)
 }
 EXPORT_SYMBOL(open_exec);
 
-int kernel_read(struct file *file, loff_t offset,
-		char *addr, unsigned long count)
-{
-	mm_segment_t old_fs;
-	loff_t pos = offset;
-	int result;
-
-	old_fs = get_fs();
-	set_fs(get_ds());
-	/* The cast to a user pointer is valid due to the set_fs() */
-	result = vfs_read(file, (void __user *)addr, count, &pos);
-	set_fs(old_fs);
-	return result;
-}
-
-EXPORT_SYMBOL(kernel_read);
-
 int kernel_read_file(struct file *file, void **buf, loff_t *size,
 		     loff_t max_size, enum kernel_read_file_id id)
 {
@@ -939,8 +922,7 @@ int kernel_read_file(struct file *file, void **buf, loff_t *size,
 
 	pos = 0;
 	while (pos < i_size) {
-		bytes = kernel_read(file, pos, (char *)(*buf) + pos,
-				    i_size - pos);
+		bytes = kernel_read(file, *buf + pos, i_size - pos, &pos);
 		if (bytes < 0) {
 			ret = bytes;
 			goto out;
@@ -948,7 +930,6 @@ int kernel_read_file(struct file *file, void **buf, loff_t *size,
 
 		if (bytes == 0)
 			break;
-		pos += bytes;
 	}
 
 	if (pos != i_size) {
@@ -1567,6 +1548,7 @@ static void bprm_fill_uid(struct linux_binprm *bprm)
 int prepare_binprm(struct linux_binprm *bprm)
 {
 	int retval;
+	loff_t pos = 0;
 
 	bprm_fill_uid(bprm);
 
@@ -1577,7 +1559,7 @@ int prepare_binprm(struct linux_binprm *bprm)
 	bprm->called_set_creds = 1;
 
 	memset(bprm->buf, 0, BINPRM_BUF_SIZE);
-	return kernel_read(bprm->file, 0, bprm->buf, BINPRM_BUF_SIZE);
+	return kernel_read(bprm->file, bprm->buf, BINPRM_BUF_SIZE, &pos);
 }
 
 EXPORT_SYMBOL(prepare_binprm);
diff --git a/fs/read_write.c b/fs/read_write.c
index 61b58c7..a2b9a47 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -413,7 +413,20 @@ ssize_t __vfs_read(struct file *file, char __user *buf, size_t count,
 	else
 		return -EINVAL;
 }
-EXPORT_SYMBOL(__vfs_read);
+
+ssize_t kernel_read(struct file *file, void *buf, size_t count, loff_t *pos)
+{
+	mm_segment_t old_fs;
+	ssize_t result;
+
+	old_fs = get_fs();
+	set_fs(get_ds());
+	/* The cast to a user pointer is valid due to the set_fs() */
+	result = vfs_read(file, (void __user *)buf, count, pos);
+	set_fs(old_fs);
+	return result;
+}
+EXPORT_SYMBOL(kernel_read);
 
 ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos)
 {
@@ -441,8 +454,6 @@ ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos)
 	return ret;
 }
 
-EXPORT_SYMBOL(vfs_read);
-
 static ssize_t new_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos)
 {
 	struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = len };
@@ -471,9 +482,8 @@ ssize_t __vfs_write(struct file *file, const char __user *p, size_t count,
 	else
 		return -EINVAL;
 }
-EXPORT_SYMBOL(__vfs_write);
 
-ssize_t __kernel_write(struct file *file, const char *buf, size_t count, loff_t *pos)
+ssize_t __kernel_write(struct file *file, const void *buf, size_t count, loff_t *pos)
 {
 	mm_segment_t old_fs;
 	const char __user *p;
@@ -496,9 +506,24 @@ ssize_t __kernel_write(struct file *file, const char *buf, size_t count, loff_t
 	inc_syscw(current);
 	return ret;
 }
-
 EXPORT_SYMBOL(__kernel_write);
 
+ssize_t kernel_write(struct file *file, const void *buf, size_t count,
+			    loff_t *pos)
+{
+	mm_segment_t old_fs;
+	ssize_t res;
+
+	old_fs = get_fs();
+	set_fs(get_ds());
+	/* The cast to a user pointer is valid due to the set_fs() */
+	res = vfs_write(file, (__force const char __user *)buf, count, pos);
+	set_fs(old_fs);
+
+	return res;
+}
+EXPORT_SYMBOL(kernel_write);
+
 ssize_t vfs_write(struct file *file, const char __user *buf, size_t count, loff_t *pos)
 {
 	ssize_t ret;
@@ -527,8 +552,6 @@ ssize_t vfs_write(struct file *file, const char __user *buf, size_t count, loff_
 	return ret;
 }
 
-EXPORT_SYMBOL(vfs_write);
-
 static inline loff_t file_pos_read(struct file *file)
 {
 	return file->f_pos;
@@ -959,9 +982,8 @@ ssize_t vfs_readv(struct file *file, const struct iovec __user *vec,
 
 	return ret;
 }
-EXPORT_SYMBOL(vfs_readv);
 
-ssize_t vfs_writev(struct file *file, const struct iovec __user *vec,
+static ssize_t vfs_writev(struct file *file, const struct iovec __user *vec,
 		   unsigned long vlen, loff_t *pos, rwf_t flags)
 {
 	struct iovec iovstack[UIO_FASTIOV];
@@ -978,7 +1000,6 @@ ssize_t vfs_writev(struct file *file, const struct iovec __user *vec,
 	}
 	return ret;
 }
-EXPORT_SYMBOL(vfs_writev);
 
 static ssize_t do_readv(unsigned long fd, const struct iovec __user *vec,
 			unsigned long vlen, rwf_t flags)
diff --git a/fs/splice.c b/fs/splice.c
index ae41201..f3084cc 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -364,22 +364,6 @@ static ssize_t kernel_readv(struct file *file, const struct kvec *vec,
 	return res;
 }
 
-ssize_t kernel_write(struct file *file, const char *buf, size_t count,
-			    loff_t pos)
-{
-	mm_segment_t old_fs;
-	ssize_t res;
-
-	old_fs = get_fs();
-	set_fs(get_ds());
-	/* The cast to a user pointer is valid due to the set_fs() */
-	res = vfs_write(file, (__force const char __user *)buf, count, &pos);
-	set_fs(old_fs);
-
-	return res;
-}
-EXPORT_SYMBOL(kernel_write);
-
 static ssize_t default_file_splice_read(struct file *in, loff_t *ppos,
 				 struct pipe_inode_info *pipe, size_t len,
 				 unsigned int flags)