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authorLinus Torvalds <torvalds@linux-foundation.org>2019-11-10 13:29:12 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2019-11-10 13:29:12 -0800
commitdd892625d0e252d967387d0a2af6dd6a864b3fdf (patch)
tree5b9b9f1ed1b820ec81fc1bfbc64dd07c715b6120 /drivers/staging/vboxsf/dir.c
parent3de2a3e93700eb5df2abfe8b7ca9d5c813381a4e (diff)
parente39fcaef7ed993950af74a584f8246022b551971 (diff)
Merge tag 'staging-5.4-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull IIO fixes and staging driver from Greg KH: "Here is a mix of a number of IIO driver fixes for 5.4-rc7, and a whole new staging driver. The IIO fixes resolve some reported issues, all are tiny. The staging driver addition is the vboxsf filesystem, which is the VirtualBox guest shared folder code. Hans has been trying to get filesystem reviewers to review the code for many months now, and Christoph finally said to just merge it in staging now as it is stand-alone and the filesystem people can review it easier over time that way. I know it's late for this big of an addition, but it is stand-alone. The code has been in linux-next for a while, long enough to pick up a few tiny fixes for it already so people are looking at it. All of these have been in linux-next with no reported issues" * tag 'staging-5.4-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: staging: Fix error return code in vboxsf_fill_super() staging: vboxsf: fix dereference of pointer dentry before it is null checked staging: vboxsf: Remove unused including <linux/version.h> staging: Add VirtualBox guest shared folder (vboxsf) support iio: adc: stm32-adc: fix stopping dma iio: imu: inv_mpu6050: fix no data on MPU6050 iio: srf04: fix wrong limitation in distance measuring iio: imu: adis16480: make sure provided frequency is positive
Diffstat (limited to 'drivers/staging/vboxsf/dir.c')
-rw-r--r--drivers/staging/vboxsf/dir.c418
1 files changed, 418 insertions, 0 deletions
diff --git a/drivers/staging/vboxsf/dir.c b/drivers/staging/vboxsf/dir.c
new file mode 100644
index 000000000000..f260b5cc1646
--- /dev/null
+++ b/drivers/staging/vboxsf/dir.c
@@ -0,0 +1,418 @@
+// SPDX-License-Identifier: MIT
+/*
+ * VirtualBox Guest Shared Folders support: Directory inode and file operations
+ *
+ * Copyright (C) 2006-2018 Oracle Corporation
+ */
+
+#include <linux/namei.h>
+#include <linux/vbox_utils.h>
+#include "vfsmod.h"
+
+static int vboxsf_dir_open(struct inode *inode, struct file *file)
+{
+ struct vboxsf_sbi *sbi = VBOXSF_SBI(inode->i_sb);
+ struct shfl_createparms params = {};
+ struct vboxsf_dir_info *sf_d;
+ int err;
+
+ sf_d = vboxsf_dir_info_alloc();
+ if (!sf_d)
+ return -ENOMEM;
+
+ params.handle = SHFL_HANDLE_NIL;
+ params.create_flags = SHFL_CF_DIRECTORY | SHFL_CF_ACT_OPEN_IF_EXISTS |
+ SHFL_CF_ACT_FAIL_IF_NEW | SHFL_CF_ACCESS_READ;
+
+ err = vboxsf_create_at_dentry(file_dentry(file), &params);
+ if (err)
+ goto err_free_dir_info;
+
+ if (params.result != SHFL_FILE_EXISTS) {
+ err = -ENOENT;
+ goto err_close;
+ }
+
+ err = vboxsf_dir_read_all(sbi, sf_d, params.handle);
+ if (err)
+ goto err_close;
+
+ vboxsf_close(sbi->root, params.handle);
+ file->private_data = sf_d;
+ return 0;
+
+err_close:
+ vboxsf_close(sbi->root, params.handle);
+err_free_dir_info:
+ vboxsf_dir_info_free(sf_d);
+ return err;
+}
+
+static int vboxsf_dir_release(struct inode *inode, struct file *file)
+{
+ if (file->private_data)
+ vboxsf_dir_info_free(file->private_data);
+
+ return 0;
+}
+
+static unsigned int vboxsf_get_d_type(u32 mode)
+{
+ unsigned int d_type;
+
+ switch (mode & SHFL_TYPE_MASK) {
+ case SHFL_TYPE_FIFO:
+ d_type = DT_FIFO;
+ break;
+ case SHFL_TYPE_DEV_CHAR:
+ d_type = DT_CHR;
+ break;
+ case SHFL_TYPE_DIRECTORY:
+ d_type = DT_DIR;
+ break;
+ case SHFL_TYPE_DEV_BLOCK:
+ d_type = DT_BLK;
+ break;
+ case SHFL_TYPE_FILE:
+ d_type = DT_REG;
+ break;
+ case SHFL_TYPE_SYMLINK:
+ d_type = DT_LNK;
+ break;
+ case SHFL_TYPE_SOCKET:
+ d_type = DT_SOCK;
+ break;
+ case SHFL_TYPE_WHITEOUT:
+ d_type = DT_WHT;
+ break;
+ default:
+ d_type = DT_UNKNOWN;
+ break;
+ }
+ return d_type;
+}
+
+static bool vboxsf_dir_emit(struct file *dir, struct dir_context *ctx)
+{
+ struct vboxsf_sbi *sbi = VBOXSF_SBI(file_inode(dir)->i_sb);
+ struct vboxsf_dir_info *sf_d = dir->private_data;
+ struct shfl_dirinfo *info;
+ struct vboxsf_dir_buf *b;
+ unsigned int d_type;
+ loff_t i, cur = 0;
+ ino_t fake_ino;
+ size_t size;
+ int err;
+
+ list_for_each_entry(b, &sf_d->info_list, head) {
+try_next_entry:
+ if (ctx->pos >= cur + b->entries) {
+ cur += b->entries;
+ continue;
+ }
+
+ /*
+ * Note the vboxsf_dir_info objects we are iterating over here
+ * are variable sized, so the info pointer may end up being
+ * unaligned. This is how we get the data from the host.
+ * Since vboxsf is only supported on x86 machines this is not
+ * a problem.
+ */
+ for (i = 0, info = b->buf; i < ctx->pos - cur; i++) {
+ size = offsetof(struct shfl_dirinfo, name.string) +
+ info->name.size;
+ info = (struct shfl_dirinfo *)((uintptr_t)info + size);
+ }
+
+ /* Info now points to the right entry, emit it. */
+ d_type = vboxsf_get_d_type(info->info.attr.mode);
+
+ /*
+ * On 32 bit systems pos is 64 signed, while ino is 32 bit
+ * unsigned so fake_ino may overflow, check for this.
+ */
+ if ((ino_t)(ctx->pos + 1) != (u64)(ctx->pos + 1)) {
+ vbg_err("vboxsf: fake ino overflow, truncating dir\n");
+ return false;
+ }
+ fake_ino = ctx->pos + 1;
+
+ if (sbi->nls) {
+ char d_name[NAME_MAX];
+
+ err = vboxsf_nlscpy(sbi, d_name, NAME_MAX,
+ info->name.string.utf8,
+ info->name.length);
+ if (err) {
+ /* skip erroneous entry and proceed */
+ ctx->pos += 1;
+ goto try_next_entry;
+ }
+
+ return dir_emit(ctx, d_name, strlen(d_name),
+ fake_ino, d_type);
+ }
+
+ return dir_emit(ctx, info->name.string.utf8, info->name.length,
+ fake_ino, d_type);
+ }
+
+ return false;
+}
+
+static int vboxsf_dir_iterate(struct file *dir, struct dir_context *ctx)
+{
+ bool keep_iterating;
+
+ for (keep_iterating = true; keep_iterating; ctx->pos += 1)
+ keep_iterating = vboxsf_dir_emit(dir, ctx);
+
+ return 0;
+}
+
+const struct file_operations vboxsf_dir_fops = {
+ .open = vboxsf_dir_open,
+ .iterate = vboxsf_dir_iterate,
+ .release = vboxsf_dir_release,
+ .read = generic_read_dir,
+ .llseek = generic_file_llseek,
+};
+
+/*
+ * This is called during name resolution/lookup to check if the @dentry in
+ * the cache is still valid. the job is handled by vboxsf_inode_revalidate.
+ */
+static int vboxsf_dentry_revalidate(struct dentry *dentry, unsigned int flags)
+{
+ if (flags & LOOKUP_RCU)
+ return -ECHILD;
+
+ if (d_really_is_positive(dentry))
+ return vboxsf_inode_revalidate(dentry) == 0;
+ else
+ return vboxsf_stat_dentry(dentry, NULL) == -ENOENT;
+}
+
+const struct dentry_operations vboxsf_dentry_ops = {
+ .d_revalidate = vboxsf_dentry_revalidate
+};
+
+/* iops */
+
+static struct dentry *vboxsf_dir_lookup(struct inode *parent,
+ struct dentry *dentry,
+ unsigned int flags)
+{
+ struct vboxsf_sbi *sbi = VBOXSF_SBI(parent->i_sb);
+ struct shfl_fsobjinfo fsinfo;
+ struct inode *inode;
+ int err;
+
+ dentry->d_time = jiffies;
+
+ err = vboxsf_stat_dentry(dentry, &fsinfo);
+ if (err) {
+ inode = (err == -ENOENT) ? NULL : ERR_PTR(err);
+ } else {
+ inode = vboxsf_new_inode(parent->i_sb);
+ if (!IS_ERR(inode))
+ vboxsf_init_inode(sbi, inode, &fsinfo);
+ }
+
+ return d_splice_alias(inode, dentry);
+}
+
+static int vboxsf_dir_instantiate(struct inode *parent, struct dentry *dentry,
+ struct shfl_fsobjinfo *info)
+{
+ struct vboxsf_sbi *sbi = VBOXSF_SBI(parent->i_sb);
+ struct vboxsf_inode *sf_i;
+ struct inode *inode;
+
+ inode = vboxsf_new_inode(parent->i_sb);
+ if (IS_ERR(inode))
+ return PTR_ERR(inode);
+
+ sf_i = VBOXSF_I(inode);
+ /* The host may have given us different attr then requested */
+ sf_i->force_restat = 1;
+ vboxsf_init_inode(sbi, inode, info);
+
+ d_instantiate(dentry, inode);
+
+ return 0;
+}
+
+static int vboxsf_dir_create(struct inode *parent, struct dentry *dentry,
+ umode_t mode, int is_dir)
+{
+ struct vboxsf_inode *sf_parent_i = VBOXSF_I(parent);
+ struct vboxsf_sbi *sbi = VBOXSF_SBI(parent->i_sb);
+ struct shfl_createparms params = {};
+ int err;
+
+ params.handle = SHFL_HANDLE_NIL;
+ params.create_flags = SHFL_CF_ACT_CREATE_IF_NEW |
+ SHFL_CF_ACT_FAIL_IF_EXISTS |
+ SHFL_CF_ACCESS_READWRITE |
+ (is_dir ? SHFL_CF_DIRECTORY : 0);
+ params.info.attr.mode = (mode & 0777) |
+ (is_dir ? SHFL_TYPE_DIRECTORY : SHFL_TYPE_FILE);
+ params.info.attr.additional = SHFLFSOBJATTRADD_NOTHING;
+
+ err = vboxsf_create_at_dentry(dentry, &params);
+ if (err)
+ return err;
+
+ if (params.result != SHFL_FILE_CREATED)
+ return -EPERM;
+
+ vboxsf_close(sbi->root, params.handle);
+
+ err = vboxsf_dir_instantiate(parent, dentry, &params.info);
+ if (err)
+ return err;
+
+ /* parent directory access/change time changed */
+ sf_parent_i->force_restat = 1;
+
+ return 0;
+}
+
+static int vboxsf_dir_mkfile(struct inode *parent, struct dentry *dentry,
+ umode_t mode, bool excl)
+{
+ return vboxsf_dir_create(parent, dentry, mode, 0);
+}
+
+static int vboxsf_dir_mkdir(struct inode *parent, struct dentry *dentry,
+ umode_t mode)
+{
+ return vboxsf_dir_create(parent, dentry, mode, 1);
+}
+
+static int vboxsf_dir_unlink(struct inode *parent, struct dentry *dentry)
+{
+ struct vboxsf_sbi *sbi = VBOXSF_SBI(parent->i_sb);
+ struct vboxsf_inode *sf_parent_i = VBOXSF_I(parent);
+ struct inode *inode = d_inode(dentry);
+ struct shfl_string *path;
+ u32 flags;
+ int err;
+
+ if (S_ISDIR(inode->i_mode))
+ flags = SHFL_REMOVE_DIR;
+ else
+ flags = SHFL_REMOVE_FILE;
+
+ if (S_ISLNK(inode->i_mode))
+ flags |= SHFL_REMOVE_SYMLINK;
+
+ path = vboxsf_path_from_dentry(sbi, dentry);
+ if (IS_ERR(path))
+ return PTR_ERR(path);
+
+ err = vboxsf_remove(sbi->root, path, flags);
+ __putname(path);
+ if (err)
+ return err;
+
+ /* parent directory access/change time changed */
+ sf_parent_i->force_restat = 1;
+
+ return 0;
+}
+
+static int vboxsf_dir_rename(struct inode *old_parent,
+ struct dentry *old_dentry,
+ struct inode *new_parent,
+ struct dentry *new_dentry,
+ unsigned int flags)
+{
+ struct vboxsf_sbi *sbi = VBOXSF_SBI(old_parent->i_sb);
+ struct vboxsf_inode *sf_old_parent_i = VBOXSF_I(old_parent);
+ struct vboxsf_inode *sf_new_parent_i = VBOXSF_I(new_parent);
+ u32 shfl_flags = SHFL_RENAME_FILE | SHFL_RENAME_REPLACE_IF_EXISTS;
+ struct shfl_string *old_path, *new_path;
+ int err;
+
+ if (flags)
+ return -EINVAL;
+
+ old_path = vboxsf_path_from_dentry(sbi, old_dentry);
+ if (IS_ERR(old_path))
+ return PTR_ERR(old_path);
+
+ new_path = vboxsf_path_from_dentry(sbi, new_dentry);
+ if (IS_ERR(new_path)) {
+ err = PTR_ERR(new_path);
+ goto err_put_old_path;
+ }
+
+ if (d_inode(old_dentry)->i_mode & S_IFDIR)
+ shfl_flags = 0;
+
+ err = vboxsf_rename(sbi->root, old_path, new_path, shfl_flags);
+ if (err == 0) {
+ /* parent directories access/change time changed */
+ sf_new_parent_i->force_restat = 1;
+ sf_old_parent_i->force_restat = 1;
+ }
+
+ __putname(new_path);
+err_put_old_path:
+ __putname(old_path);
+ return err;
+}
+
+static int vboxsf_dir_symlink(struct inode *parent, struct dentry *dentry,
+ const char *symname)
+{
+ struct vboxsf_inode *sf_parent_i = VBOXSF_I(parent);
+ struct vboxsf_sbi *sbi = VBOXSF_SBI(parent->i_sb);
+ int symname_size = strlen(symname) + 1;
+ struct shfl_string *path, *ssymname;
+ struct shfl_fsobjinfo info;
+ int err;
+
+ path = vboxsf_path_from_dentry(sbi, dentry);
+ if (IS_ERR(path))
+ return PTR_ERR(path);
+
+ ssymname = kmalloc(SHFLSTRING_HEADER_SIZE + symname_size, GFP_KERNEL);
+ if (!ssymname) {
+ __putname(path);
+ return -ENOMEM;
+ }
+ ssymname->length = symname_size - 1;
+ ssymname->size = symname_size;
+ memcpy(ssymname->string.utf8, symname, symname_size);
+
+ err = vboxsf_symlink(sbi->root, path, ssymname, &info);
+ kfree(ssymname);
+ __putname(path);
+ if (err) {
+ /* -EROFS means symlinks are note support -> -EPERM */
+ return (err == -EROFS) ? -EPERM : err;
+ }
+
+ err = vboxsf_dir_instantiate(parent, dentry, &info);
+ if (err)
+ return err;
+
+ /* parent directory access/change time changed */
+ sf_parent_i->force_restat = 1;
+ return 0;
+}
+
+const struct inode_operations vboxsf_dir_iops = {
+ .lookup = vboxsf_dir_lookup,
+ .create = vboxsf_dir_mkfile,
+ .mkdir = vboxsf_dir_mkdir,
+ .rmdir = vboxsf_dir_unlink,
+ .unlink = vboxsf_dir_unlink,
+ .rename = vboxsf_dir_rename,
+ .symlink = vboxsf_dir_symlink,
+ .getattr = vboxsf_getattr,
+ .setattr = vboxsf_setattr,
+};