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

10 files changed, 34 insertions, 82 deletions

diff --git a/drivers/media/pci/cx25821/cx25821-audio-upstream.c b/drivers/media/pci/cx25821/cx25821-audio-upstream.c
index b94eb1c0023d..ada26d4acfb4 100644
--- a/drivers/media/pci/cx25821/cx25821-audio-upstream.c
+++ b/drivers/media/pci/cx25821/cx25821-audio-upstream.c
@@ -277,7 +277,7 @@ static int cx25821_get_audio_data(struct cx25821_dev *dev,
                 p = (char *)dev->_audiodata_buf_virt_addr + frame_offset;
 
         for (i = 0; i < dev->_audio_lines_count; i++) {
-                int n = kernel_read(file, file_offset, mybuf, AUDIO_LINE_SIZE);
+                int n = kernel_read(file, mybuf, AUDIO_LINE_SIZE, &file_offset);
                 if (n < AUDIO_LINE_SIZE) {
                         pr_info("Done: exit %s() since no more bytes to read from Audio file\n",
                                 __func__);
@@ -290,7 +290,6 @@ static int cx25821_get_audio_data(struct cx25821_dev *dev,
                         memcpy(p, mybuf, n);
                         p += n;
                 }
-                file_offset += n;
         }
         dev->_audioframe_count++;
         fput(file);
@@ -318,7 +317,7 @@ static int cx25821_openfile_audio(struct cx25821_dev *dev,
 {
         char *p = (void *)dev->_audiodata_buf_virt_addr;
         struct file *file;
-        loff_t offset;
+        loff_t file_offset = 0;
         int i, j;
 
         file = filp_open(dev->_audiofilename, O_RDONLY | O_LARGEFILE, 0);
@@ -328,11 +327,11 @@ static int cx25821_openfile_audio(struct cx25821_dev *dev,
                 return PTR_ERR(file);
         }
 
-        for (j = 0, offset = 0; j < NUM_AUDIO_FRAMES; j++) {
+        for (j = 0; j < NUM_AUDIO_FRAMES; j++) {
                 for (i = 0; i < dev->_audio_lines_count; i++) {
                         char buf[AUDIO_LINE_SIZE];
-                        int n = kernel_read(file, offset, buf,
-                                                AUDIO_LINE_SIZE);
+                        loff_t offset = file_offset;
+                        int n = kernel_read(file, buf, AUDIO_LINE_SIZE, &file_offset);
 
                         if (n < AUDIO_LINE_SIZE) {
                                 pr_info("Done: exit %s() since no more bytes to read from Audio file\n",
@@ -344,8 +343,6 @@ static int cx25821_openfile_audio(struct cx25821_dev *dev,
 
                         if (p)
                                 memcpy(p + offset, buf, n);
-
-                        offset += n;
                 }
                 dev->_audioframe_count++;
         }
diff --git a/drivers/mtd/nand/nandsim.c b/drivers/mtd/nand/nandsim.c
index fec613221958..246b4393118e 100644
--- a/drivers/mtd/nand/nandsim.c
+++ b/drivers/mtd/nand/nandsim.c
@@ -1356,7 +1356,7 @@ static ssize_t read_file(struct nandsim *ns, struct file *file, void *buf, size_
         if (err)
                 return err;
         noreclaim_flag = memalloc_noreclaim_save();
-        tx = kernel_read(file, pos, buf, count);
+        tx = kernel_read(file, buf, count, &pos);
         memalloc_noreclaim_restore(noreclaim_flag);
         put_pages(ns);
         return tx;
@@ -1372,7 +1372,7 @@ static ssize_t write_file(struct nandsim *ns, struct file *file, void *buf, size
         if (err)
                 return err;
         noreclaim_flag = memalloc_noreclaim_save();
-        tx = kernel_write(file, buf, count, pos);
+        tx = kernel_write(file, buf, count, &pos);
         memalloc_noreclaim_restore(noreclaim_flag);
         put_pages(ns);
         return tx;
diff --git a/drivers/staging/android/ashmem.c b/drivers/staging/android/ashmem.c
index 6ba270e0494d..0f695df14c9d 100644
--- a/drivers/staging/android/ashmem.c
+++ b/drivers/staging/android/ashmem.c
@@ -294,19 +294,9 @@ static int ashmem_release(struct inode *ignored, struct file *file)
         return 0;
 }
 
-/**
- * ashmem_read() - Reads a set of bytes from an Ashmem-enabled file
- * @file:          The associated backing file.
- * @buf:           The buffer of data being written to
- * @len:           The number of bytes being read
- * @pos:           The position of the first byte to read.
- *
- * Return: 0 if successful, or another return code if not.
- */
-static ssize_t ashmem_read(struct file *file, char __user *buf,
-                           size_t len, loff_t *pos)
+static ssize_t ashmem_read_iter(struct kiocb *iocb, struct iov_iter *iter)
 {
-        struct ashmem_area *asma = file->private_data;
+        struct ashmem_area *asma = iocb->ki_filp->private_data;
         int ret = 0;
 
         mutex_lock(&ashmem_mutex);
@@ -320,20 +310,17 @@ static ssize_t ashmem_read(struct file *file, char __user *buf,
                 goto out_unlock;
         }
 
-        mutex_unlock(&ashmem_mutex);
-
         /*
          * asma and asma->file are used outside the lock here.  We assume
          * once asma->file is set it will never be changed, and will not
          * be destroyed until all references to the file are dropped and
          * ashmem_release is called.
          */
-        ret = __vfs_read(asma->file, buf, len, pos);
-        if (ret >= 0)
-                /** Update backing file pos, since f_ops->read() doesn't */
-                asma->file->f_pos = *pos;
-        return ret;
-
+        mutex_unlock(&ashmem_mutex);
+        ret = vfs_iter_read(asma->file, iter, &iocb->ki_pos, 0);
+        mutex_lock(&ashmem_mutex);
+        if (ret > 0)
+                asma->file->f_pos = iocb->ki_pos;
 out_unlock:
         mutex_unlock(&ashmem_mutex);
         return ret;
@@ -834,7 +821,7 @@ static const struct file_operations ashmem_fops = {
         .owner = THIS_MODULE,
         .open = ashmem_open,
         .release = ashmem_release,
-        .read = ashmem_read,
+        .read_iter = ashmem_read_iter,
         .llseek = ashmem_llseek,
         .mmap = ashmem_mmap,
         .unlocked_ioctl = ashmem_ioctl,
diff --git a/drivers/staging/comedi/drivers/serial2002.c b/drivers/staging/comedi/drivers/serial2002.c
index 0d33e520f635..cc18e25103ca 100644
--- a/drivers/staging/comedi/drivers/serial2002.c
+++ b/drivers/staging/comedi/drivers/serial2002.c
@@ -106,16 +106,8 @@ static long serial2002_tty_ioctl(struct file *f, unsigned int op,
 
 static int serial2002_tty_write(struct file *f, unsigned char *buf, int count)
 {
-        const char __user *p = (__force const char __user *)buf;
-        int result;
-        loff_t offset = 0;
-        mm_segment_t oldfs;
-
-        oldfs = get_fs();
-        set_fs(KERNEL_DS);
-        result = __vfs_write(f, p, count, &offset);
-        set_fs(oldfs);
-        return result;
+        loff_t pos = 0;
+        return kernel_write(f, buf, count, &pos);
 }
 
 static void serial2002_tty_read_poll_wait(struct file *f, int timeout)
@@ -148,19 +140,14 @@ static int serial2002_tty_read(struct file *f, int timeout)
 {
         unsigned char ch;
         int result;
+        loff_t pos = 0;
 
         result = -1;
         if (!IS_ERR(f)) {
-                mm_segment_t oldfs;
-                char __user *p = (__force char __user *)&ch;
-                loff_t offset = 0;
-
-                oldfs = get_fs();
-                set_fs(KERNEL_DS);
                 if (f->f_op->poll) {
                         serial2002_tty_read_poll_wait(f, timeout);
 
-                        if (__vfs_read(f, p, 1, &offset) == 1)
+                        if (kernel_read(f, &ch, 1, &pos) == 1)
                                 result = ch;
                 } else {
                         /* Device does not support poll, busy wait */
@@ -171,14 +158,13 @@ static int serial2002_tty_read(struct file *f, int timeout)
                                 if (retries >= timeout)
                                         break;
 
-                                if (__vfs_read(f, p, 1, &offset) == 1) {
+                                if (kernel_read(f, &ch, 1, &pos) == 1) {
                                         result = ch;
                                         break;
                                 }
                                 usleep_range(100, 1000);
                         }
                 }
-                set_fs(oldfs);
         }
         return result;
 }
diff --git a/drivers/staging/lustre/lnet/libcfs/tracefile.c b/drivers/staging/lustre/lnet/libcfs/tracefile.c
index 68f283a2744c..f916b475e767 100644
--- a/drivers/staging/lustre/lnet/libcfs/tracefile.c
+++ b/drivers/staging/lustre/lnet/libcfs/tracefile.c
@@ -731,8 +731,7 @@ int cfs_tracefile_dump_all_pages(char *filename)
                 __LASSERT_TAGE_INVARIANT(tage);
 
                 buf = kmap(tage->page);
-                rc = vfs_write(filp, (__force const char __user *)buf,
-                               tage->used, &filp->f_pos);
+                rc = kernel_write(filp, buf, tage->used, &filp->f_pos);
                 kunmap(tage->page);
 
                 if (rc != (int)tage->used) {
@@ -976,7 +975,6 @@ static int tracefiled(void *arg)
         struct tracefiled_ctl *tctl = arg;
         struct cfs_trace_page *tage;
         struct cfs_trace_page *tmp;
-        mm_segment_t __oldfs;
         struct file *filp;
         char *buf;
         int last_loop = 0;
@@ -1014,8 +1012,6 @@ static int tracefiled(void *arg)
                         __LASSERT(list_empty(&pc.pc_pages));
                         goto end_loop;
                 }
-                __oldfs = get_fs();
-                set_fs(get_ds());
 
                 list_for_each_entry_safe(tage, tmp, &pc.pc_pages, linkage) {
                         static loff_t f_pos;
@@ -1028,8 +1024,7 @@ static int tracefiled(void *arg)
                                 f_pos = i_size_read(file_inode(filp));
 
                         buf = kmap(tage->page);
-                        rc = vfs_write(filp, (__force const char __user *)buf,
-                                       tage->used, &f_pos);
+                        rc = kernel_write(filp, buf, tage->used, &f_pos);
                         kunmap(tage->page);
 
                         if (rc != (int)tage->used) {
@@ -1040,7 +1035,6 @@ static int tracefiled(void *arg)
                                 break;
                         }
                 }
-                set_fs(__oldfs);
 
                 filp_close(filp, NULL);
                 put_pages_on_daemon_list(&pc);
diff --git a/drivers/staging/lustre/lustre/obdclass/kernelcomm.c b/drivers/staging/lustre/lustre/obdclass/kernelcomm.c
index 8f0707a27a83..4f0a42633d5a 100644
--- a/drivers/staging/lustre/lustre/obdclass/kernelcomm.c
+++ b/drivers/staging/lustre/lustre/obdclass/kernelcomm.c
@@ -52,7 +52,6 @@ int libcfs_kkuc_msg_put(struct file *filp, void *payload)
         struct kuc_hdr *kuch = (struct kuc_hdr *)payload;
         ssize_t count = kuch->kuc_msglen;
         loff_t offset = 0;
-        mm_segment_t fs;
         int rc = -ENXIO;
 
         if (IS_ERR_OR_NULL(filp))
@@ -63,18 +62,14 @@ int libcfs_kkuc_msg_put(struct file *filp, void *payload)
                 return rc;
         }
 
-        fs = get_fs();
-        set_fs(KERNEL_DS);
         while (count > 0) {
-                rc = vfs_write(filp, (void __force __user *)payload,
-                               count, &offset);
+                rc = kernel_write(filp, payload, count, &offset);
                 if (rc < 0)
                         break;
                 count -= rc;
                 payload += rc;
                 rc = 0;
         }
-        set_fs(fs);
 
         if (rc < 0)
                 CWARN("message send failed (%d)\n", rc);
diff --git a/drivers/target/target_core_alua.c b/drivers/target/target_core_alua.c
index a91b7c25ffd4..928127642574 100644
--- a/drivers/target/target_core_alua.c
+++ b/drivers/target/target_core_alua.c
@@ -896,13 +896,14 @@ static int core_alua_write_tpg_metadata(
         u32 md_buf_len)
 {
         struct file *file = filp_open(path, O_RDWR | O_CREAT | O_TRUNC, 0600);
+        loff_t pos = 0;
         int ret;
 
         if (IS_ERR(file)) {
                 pr_err("filp_open(%s) for ALUA metadata failed\n", path);
                 return -ENODEV;
         }
-        ret = kernel_write(file, md_buf, md_buf_len, 0);
+        ret = kernel_write(file, md_buf, md_buf_len, &pos);
         if (ret < 0)
                 pr_err("Error writing ALUA metadata file: %s\n", path);
         fput(file);
diff --git a/drivers/target/target_core_file.c b/drivers/target/target_core_file.c
index 24cf11d9e50a..c629817a8854 100644
--- a/drivers/target/target_core_file.c
+++ b/drivers/target/target_core_file.c
@@ -443,7 +443,7 @@ fd_do_prot_fill(struct se_device *se_dev, sector_t lba, sector_t nolb,
 
         for (prot = 0; prot < prot_length;) {
                 sector_t len = min_t(sector_t, bufsize, prot_length - prot);
-                ssize_t ret = kernel_write(prot_fd, buf, len, pos + prot);
+                ssize_t ret = kernel_write(prot_fd, buf, len, &pos);
 
                 if (ret != len) {
                         pr_err("vfs_write to prot file failed: %zd\n", ret);
diff --git a/drivers/target/target_core_pr.c b/drivers/target/target_core_pr.c
index 6d5def64db61..dd2cd8048582 100644
--- a/drivers/target/target_core_pr.c
+++ b/drivers/target/target_core_pr.c
@@ -1974,6 +1974,7 @@ static int __core_scsi3_write_aptpl_to_file(
         char path[512];
         u32 pr_aptpl_buf_len;
         int ret;
+        loff_t pos = 0;
 
         memset(path, 0, 512);
 
@@ -1993,7 +1994,7 @@ static int __core_scsi3_write_aptpl_to_file(
 
         pr_aptpl_buf_len = (strlen(buf) + 1); /* Add extra for NULL */
 
-        ret = kernel_write(file, buf, pr_aptpl_buf_len, 0);
+        ret = kernel_write(file, buf, pr_aptpl_buf_len, &pos);
 
         if (ret < 0)
                 pr_debug("Error writing APTPL metadata file: %s\n", path);
diff --git a/drivers/usb/gadget/function/f_mass_storage.c b/drivers/usb/gadget/function/f_mass_storage.c
index f95bddd6513f..d6bd0244b008 100644
--- a/drivers/usb/gadget/function/f_mass_storage.c
+++ b/drivers/usb/gadget/function/f_mass_storage.c
@@ -686,9 +686,8 @@ static int do_read(struct fsg_common *common)
 
                 /* Perform the read */
                 file_offset_tmp = file_offset;
-                nread = vfs_read(curlun->filp,
-                                 (char __user *)bh->buf,
-                                 amount, &file_offset_tmp);
+                nread = kernel_read(curlun->filp, bh->buf, amount,
+                                &file_offset_tmp);
                 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
                       (unsigned long long)file_offset, (int)nread);
                 if (signal_pending(current))
@@ -883,8 +882,8 @@ static int do_write(struct fsg_common *common)
 
                 /* Perform the write */
                 file_offset_tmp = file_offset;
-                nwritten = vfs_write(curlun->filp, (char __user *)bh->buf,
-                                amount, &file_offset_tmp);
+                nwritten = kernel_write(curlun->filp, bh->buf, amount,
+                                &file_offset_tmp);
                 VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
                                 (unsigned long long)file_offset, (int)nwritten);
                 if (signal_pending(current))
@@ -1021,9 +1020,8 @@ static int do_verify(struct fsg_common *common)
 
                 /* Perform the read */
                 file_offset_tmp = file_offset;
-                nread = vfs_read(curlun->filp,
-                                (char __user *) bh->buf,
-                                amount, &file_offset_tmp);
+                nread = kernel_read(curlun->filp, bh->buf, amount,
+                                &file_offset_tmp);
                 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
                                 (unsigned long long) file_offset,
                                 (int) nread);
@@ -2453,13 +2451,6 @@ static int fsg_main_thread(void *common_)
         /* Allow the thread to be frozen */
         set_freezable();
 
-        /*
-         * Arrange for userspace references to be interpreted as kernel
-         * pointers.  That way we can pass a kernel pointer to a routine
-         * that expects a __user pointer and it will work okay.
-         */
-        set_fs(get_ds());
-
         /* The main loop */
         while (common->state != FSG_STATE_TERMINATED) {
                 if (exception_in_progress(common) || signal_pending(current)) {