1 files changed, 168 insertions, 52 deletions

diff --git a/fs/fat/file.c b/fs/fat/file.c
index 9b104f543056..4fc49a614fb8 100644
--- a/fs/fat/file.c
+++ b/fs/fat/file.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  *  linux/fs/fat/file.c
  *
@@ -10,22 +11,23 @@
 #include <linux/module.h>
 #include <linux/compat.h>
 #include <linux/mount.h>
-#include <linux/time.h>
-#include <linux/buffer_head.h>
-#include <linux/writeback.h>
-#include <linux/backing-dev.h>
 #include <linux/blkdev.h>
+#include <linux/backing-dev.h>
 #include <linux/fsnotify.h>
 #include <linux/security.h>
+#include <linux/falloc.h>
 #include "fat.h"
 
+static long fat_fallocate(struct file *file, int mode,
+			  loff_t offset, loff_t len);
+
 static int fat_ioctl_get_attributes(struct inode *inode, u32 __user *user_attr)
 {
 	u32 attr;
 
-	mutex_lock(&inode->i_mutex);
+	inode_lock_shared(inode);
 	attr = fat_make_attrs(inode);
-	mutex_unlock(&inode->i_mutex);
+	inode_unlock_shared(inode);
 
 	return put_user(attr, user_attr);
 }
@@ -46,7 +48,7 @@ static int fat_ioctl_set_attributes(struct file *file, u32 __user *user_attr)
 	err = mnt_want_write_file(file);
 	if (err)
 		goto out;
-	mutex_lock(&inode->i_mutex);
+	inode_lock(inode);
 
 	/*
 	 * ATTR_VOLUME and ATTR_DIR cannot be changed; this also
@@ -62,7 +64,7 @@ static int fat_ioctl_set_attributes(struct file *file, u32 __user *user_attr)
 
 	/* Equivalent to a chmod() */
 	ia.ia_valid = ATTR_MODE | ATTR_CTIME;
-	ia.ia_ctime = current_fs_time(inode->i_sb);
+	ia.ia_ctime = current_time(inode);
 	if (is_dir)
 		ia.ia_mode = fat_make_mode(sbi, attr, S_IRWXUGO);
 	else {
@@ -88,12 +90,13 @@ static int fat_ioctl_set_attributes(struct file *file, u32 __user *user_attr)
 	 * out the RO attribute for checking by the security
 	 * module, just because it maps to a file mode.
 	 */
-	err = security_inode_setattr(file->f_path.dentry, &ia);
+	err = security_inode_setattr(file_mnt_idmap(file),
+				     file->f_path.dentry, &ia);
 	if (err)
 		goto out_unlock_inode;
 
 	/* This MUST be done before doing anything irreversible... */
-	err = fat_setattr(file->f_path.dentry, &ia);
+	err = fat_setattr(file_mnt_idmap(file), file->f_path.dentry, &ia);
 	if (err)
 		goto out_unlock_inode;
 
@@ -108,7 +111,7 @@ static int fat_ioctl_set_attributes(struct file *file, u32 __user *user_attr)
 	fat_save_attrs(inode, attr);
 	mark_inode_dirty(inode);
 out_unlock_inode:
-	mutex_unlock(&inode->i_mutex);
+	inode_unlock(inode);
 	mnt_drop_write_file(file);
 out:
 	return err;
@@ -120,6 +123,36 @@ static int fat_ioctl_get_volume_id(struct inode *inode, u32 __user *user_attr)
 	return put_user(sbi->vol_id, user_attr);
 }
 
+static int fat_ioctl_fitrim(struct inode *inode, unsigned long arg)
+{
+	struct super_block *sb = inode->i_sb;
+	struct fstrim_range __user *user_range;
+	struct fstrim_range range;
+	int err;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	if (!bdev_max_discard_sectors(sb->s_bdev))
+		return -EOPNOTSUPP;
+
+	user_range = (struct fstrim_range __user *)arg;
+	if (copy_from_user(&range, user_range, sizeof(range)))
+		return -EFAULT;
+
+	range.minlen = max_t(unsigned int, range.minlen,
+			     bdev_discard_granularity(sb->s_bdev));
+
+	err = fat_trim_fs(inode, &range);
+	if (err < 0)
+		return err;
+
+	if (copy_to_user(user_range, &range, sizeof(range)))
+		return -EFAULT;
+
+	return 0;
+}
+
 long fat_generic_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 {
 	struct inode *inode = file_inode(filp);
@@ -132,26 +165,20 @@ long fat_generic_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 		return fat_ioctl_set_attributes(filp, user_attr);
 	case FAT_IOCTL_GET_VOLUME_ID:
 		return fat_ioctl_get_volume_id(inode, user_attr);
+	case FITRIM:
+		return fat_ioctl_fitrim(inode, arg);
 	default:
 		return -ENOTTY;	/* Inappropriate ioctl for device */
 	}
 }
 
-#ifdef CONFIG_COMPAT
-static long fat_generic_compat_ioctl(struct file *filp, unsigned int cmd,
-				      unsigned long arg)
-
-{
-	return fat_generic_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
-}
-#endif
-
 static int fat_file_release(struct inode *inode, struct file *filp)
 {
 	if ((filp->f_mode & FMODE_WRITE) &&
-	     MSDOS_SB(inode->i_sb)->options.flush) {
+	    MSDOS_SB(inode->i_sb)->options.flush) {
 		fat_flush_inodes(inode->i_sb, inode, NULL);
-		congestion_wait(BLK_RW_ASYNC, HZ/10);
+		set_current_state(TASK_UNINTERRUPTIBLE);
+		io_schedule_timeout(HZ/10);
 	}
 	return 0;
 }
@@ -159,29 +186,32 @@ static int fat_file_release(struct inode *inode, struct file *filp)
 int fat_file_fsync(struct file *filp, loff_t start, loff_t end, int datasync)
 {
 	struct inode *inode = filp->f_mapping->host;
-	int res, err;
+	int err;
+
+	err = __generic_file_fsync(filp, start, end, datasync);
+	if (err)
+		return err;
 
-	res = generic_file_fsync(filp, start, end, datasync);
 	err = sync_mapping_buffers(MSDOS_SB(inode->i_sb)->fat_inode->i_mapping);
+	if (err)
+		return err;
 
-	return res ? res : err;
+	return blkdev_issue_flush(inode->i_sb->s_bdev);
 }
 
 
 const struct file_operations fat_file_operations = {
 	.llseek		= generic_file_llseek,
-	.read		= do_sync_read,
-	.write		= do_sync_write,
-	.aio_read	= generic_file_aio_read,
-	.aio_write	= generic_file_aio_write,
-	.mmap		= generic_file_mmap,
+	.read_iter	= generic_file_read_iter,
+	.write_iter	= generic_file_write_iter,
+	.mmap_prepare	= generic_file_mmap_prepare,
 	.release	= fat_file_release,
 	.unlocked_ioctl	= fat_generic_ioctl,
-#ifdef CONFIG_COMPAT
-	.compat_ioctl	= fat_generic_compat_ioctl,
-#endif
+	.compat_ioctl	= compat_ptr_ioctl,
 	.fsync		= fat_file_fsync,
-	.splice_read	= generic_file_splice_read,
+	.splice_read	= filemap_splice_read,
+	.splice_write	= iter_file_splice_write,
+	.fallocate	= fat_fallocate,
 };
 
 static int fat_cont_expand(struct inode *inode, loff_t size)
@@ -194,7 +224,7 @@ static int fat_cont_expand(struct inode *inode, loff_t size)
 	if (err)
 		goto out;
 
-	inode->i_ctime = inode->i_mtime = CURRENT_TIME_SEC;
+	fat_truncate_time(inode, NULL, S_CTIME|S_MTIME);
 	mark_inode_dirty(inode);
 	if (IS_SYNC(inode)) {
 		int err2;
@@ -220,6 +250,62 @@ out:
 	return err;
 }
 
+/*
+ * Preallocate space for a file. This implements fat's fallocate file
+ * operation, which gets called from sys_fallocate system call. User
+ * space requests len bytes at offset. If FALLOC_FL_KEEP_SIZE is set
+ * we just allocate clusters without zeroing them out. Otherwise we
+ * allocate and zero out clusters via an expanding truncate.
+ */
+static long fat_fallocate(struct file *file, int mode,
+			  loff_t offset, loff_t len)
+{
+	int nr_cluster; /* Number of clusters to be allocated */
+	loff_t mm_bytes; /* Number of bytes to be allocated for file */
+	loff_t ondisksize; /* block aligned on-disk size in bytes*/
+	struct inode *inode = file->f_mapping->host;
+	struct super_block *sb = inode->i_sb;
+	struct msdos_sb_info *sbi = MSDOS_SB(sb);
+	int err = 0;
+
+	/* No support for hole punch or other fallocate flags. */
+	if (mode & ~FALLOC_FL_KEEP_SIZE)
+		return -EOPNOTSUPP;
+
+	/* No support for dir */
+	if (!S_ISREG(inode->i_mode))
+		return -EOPNOTSUPP;
+
+	inode_lock(inode);
+	if (mode & FALLOC_FL_KEEP_SIZE) {
+		ondisksize = inode->i_blocks << 9;
+		if ((offset + len) <= ondisksize)
+			goto error;
+
+		/* First compute the number of clusters to be allocated */
+		mm_bytes = offset + len - ondisksize;
+		nr_cluster = (mm_bytes + (sbi->cluster_size - 1)) >>
+			sbi->cluster_bits;
+
+		/* Start the allocation.We are not zeroing out the clusters */
+		while (nr_cluster-- > 0) {
+			err = fat_add_cluster(inode);
+			if (err)
+				goto error;
+		}
+	} else {
+		if ((offset + len) <= i_size_read(inode))
+			goto error;
+
+		/* This is just an expanding truncate */
+		err = fat_cont_expand(inode, (offset + len));
+	}
+
+error:
+	inode_unlock(inode);
+	return err;
+}
+
 /* Free all clusters after the skip'th cluster. */
 static int fat_free(struct inode *inode, int skip)
 {
@@ -241,7 +327,7 @@ static int fat_free(struct inode *inode, int skip)
 		MSDOS_I(inode)->i_logstart = 0;
 	}
 	MSDOS_I(inode)->i_attrs |= ATTR_ARCH;
-	inode->i_ctime = inode->i_mtime = CURRENT_TIME_SEC;
+	fat_truncate_time(inode, NULL, S_CTIME|S_MTIME);
 	if (wait) {
 		err = fat_sync_inode(inode);
 		if (err) {
@@ -309,16 +395,25 @@ void fat_truncate_blocks(struct inode *inode, loff_t offset)
 	fat_flush_inodes(inode->i_sb, inode, NULL);
 }
 
-int fat_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
+int fat_getattr(struct mnt_idmap *idmap, const struct path *path,
+		struct kstat *stat, u32 request_mask, unsigned int flags)
 {
-	struct inode *inode = dentry->d_inode;
-	generic_fillattr(inode, stat);
-	stat->blksize = MSDOS_SB(inode->i_sb)->cluster_size;
+	struct inode *inode = d_inode(path->dentry);
+	struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
+
+	generic_fillattr(idmap, request_mask, inode, stat);
+	stat->blksize = sbi->cluster_size;
 
-	if (MSDOS_SB(inode->i_sb)->options.nfs == FAT_NFS_NOSTALE_RO) {
+	if (sbi->options.nfs == FAT_NFS_NOSTALE_RO) {
 		/* Use i_pos for ino. This is used as fileid of nfs. */
-		stat->ino = fat_i_pos_read(MSDOS_SB(inode->i_sb), inode);
+		stat->ino = fat_i_pos_read(sbi, inode);
 	}
+
+	if (sbi->options.isvfat && request_mask & STATX_BTIME) {
+		stat->result_mask |= STATX_BTIME;
+		stat->btime = MSDOS_I(inode)->i_crtime;
+	}
+
 	return 0;
 }
 EXPORT_SYMBOL_GPL(fat_getattr);
@@ -361,12 +456,14 @@ static int fat_sanitize_mode(const struct msdos_sb_info *sbi,
 	return 0;
 }
 
-static int fat_allow_set_time(struct msdos_sb_info *sbi, struct inode *inode)
+static int fat_allow_set_time(struct mnt_idmap *idmap,
+			      struct msdos_sb_info *sbi, struct inode *inode)
 {
 	umode_t allow_utime = sbi->options.allow_utime;
 
-	if (!uid_eq(current_fsuid(), inode->i_uid)) {
-		if (in_group_p(inode->i_gid))
+	if (!vfsuid_eq_kuid(i_uid_into_vfsuid(idmap, inode),
+			    current_fsuid())) {
+		if (vfsgid_in_group_p(i_gid_into_vfsgid(idmap, inode)))
 			allow_utime >>= 3;
 		if (allow_utime & MAY_WRITE)
 			return 1;
@@ -380,21 +477,22 @@ static int fat_allow_set_time(struct msdos_sb_info *sbi, struct inode *inode)
 /* valid file mode bits */
 #define FAT_VALID_MODE	(S_IFREG | S_IFDIR | S_IRWXUGO)
 
-int fat_setattr(struct dentry *dentry, struct iattr *attr)
+int fat_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
+		struct iattr *attr)
 {
 	struct msdos_sb_info *sbi = MSDOS_SB(dentry->d_sb);
-	struct inode *inode = dentry->d_inode;
+	struct inode *inode = d_inode(dentry);
 	unsigned int ia_valid;
 	int error;
 
 	/* Check for setting the inode time. */
 	ia_valid = attr->ia_valid;
 	if (ia_valid & TIMES_SET_FLAGS) {
-		if (fat_allow_set_time(sbi, inode))
+		if (fat_allow_set_time(idmap, sbi, inode))
 			attr->ia_valid &= ~TIMES_SET_FLAGS;
 	}
 
-	error = inode_change_ok(inode, attr);
+	error = setattr_prepare(idmap, dentry, attr);
 	attr->ia_valid = ia_valid;
 	if (error) {
 		if (sbi->options.quiet)
@@ -420,9 +518,11 @@ int fat_setattr(struct dentry *dentry, struct iattr *attr)
 	}
 
 	if (((attr->ia_valid & ATTR_UID) &&
-	     (!uid_eq(attr->ia_uid, sbi->options.fs_uid))) ||
+	     (!uid_eq(from_vfsuid(idmap, i_user_ns(inode), attr->ia_vfsuid),
+		      sbi->options.fs_uid))) ||
 	    ((attr->ia_valid & ATTR_GID) &&
-	     (!gid_eq(attr->ia_gid, sbi->options.fs_gid))) ||
+	     (!gid_eq(from_vfsgid(idmap, i_user_ns(inode), attr->ia_vfsgid),
+		      sbi->options.fs_gid))) ||
 	    ((attr->ia_valid & ATTR_MODE) &&
 	     (attr->ia_mode & ~FAT_VALID_MODE)))
 		error = -EPERM;
@@ -443,13 +543,28 @@ int fat_setattr(struct dentry *dentry, struct iattr *attr)
 	}
 
 	if (attr->ia_valid & ATTR_SIZE) {
+		error = fat_block_truncate_page(inode, attr->ia_size);
+		if (error)
+			goto out;
 		down_write(&MSDOS_I(inode)->truncate_lock);
 		truncate_setsize(inode, attr->ia_size);
 		fat_truncate_blocks(inode, attr->ia_size);
 		up_write(&MSDOS_I(inode)->truncate_lock);
 	}
 
-	setattr_copy(inode, attr);
+	/*
+	 * setattr_copy can't truncate these appropriately, so we'll
+	 * copy them ourselves
+	 */
+	if (attr->ia_valid & ATTR_ATIME)
+		fat_truncate_time(inode, &attr->ia_atime, S_ATIME);
+	if (attr->ia_valid & ATTR_CTIME)
+		fat_truncate_time(inode, &attr->ia_ctime, S_CTIME);
+	if (attr->ia_valid & ATTR_MTIME)
+		fat_truncate_time(inode, &attr->ia_mtime, S_MTIME);
+	attr->ia_valid &= ~(ATTR_ATIME|ATTR_CTIME|ATTR_MTIME);
+
+	setattr_copy(idmap, inode, attr);
 	mark_inode_dirty(inode);
 out:
 	return error;
@@ -459,4 +574,5 @@ EXPORT_SYMBOL_GPL(fat_setattr);
 const struct inode_operations fat_file_inode_operations = {
 	.setattr	= fat_setattr,
 	.getattr	= fat_getattr,
+	.update_time	= fat_update_time,
 };