From 4352b8aee98005853aa63f57d6377282de17a33f Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 23 Aug 2026 13:28:57 -0700 Subject: Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ... --- fs/btrfs/export.c | 307 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 307 insertions(+) create mode 100644 fs/btrfs/export.c (limited to 'fs/btrfs/export.c') diff --git a/fs/btrfs/export.c b/fs/btrfs/export.c new file mode 100644 index 000000000..230d9326b --- /dev/null +++ b/fs/btrfs/export.c @@ -0,0 +1,307 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include +#include "ctree.h" +#include "disk-io.h" +#include "btrfs_inode.h" +#include "export.h" +#include "accessors.h" +#include "super.h" + +#define BTRFS_FID_SIZE_NON_CONNECTABLE (offsetof(struct btrfs_fid, \ + parent_objectid) / 4) +#define BTRFS_FID_SIZE_CONNECTABLE (offsetof(struct btrfs_fid, \ + parent_root_objectid) / 4) +#define BTRFS_FID_SIZE_CONNECTABLE_ROOT (sizeof(struct btrfs_fid) / 4) + +static int btrfs_encode_fh(struct inode *inode, u32 *fh, int *max_len, + struct inode *parent) +{ + struct btrfs_fid *fid = (struct btrfs_fid *)fh; + int len = *max_len; + int type; + + if (parent && (len < BTRFS_FID_SIZE_CONNECTABLE)) { + if (btrfs_root_id(BTRFS_I(inode)->root) != + btrfs_root_id(BTRFS_I(parent)->root)) + *max_len = BTRFS_FID_SIZE_CONNECTABLE_ROOT; + else + *max_len = BTRFS_FID_SIZE_CONNECTABLE; + return FILEID_INVALID; + } else if (len < BTRFS_FID_SIZE_NON_CONNECTABLE) { + *max_len = BTRFS_FID_SIZE_NON_CONNECTABLE; + return FILEID_INVALID; + } + + len = BTRFS_FID_SIZE_NON_CONNECTABLE; + type = FILEID_BTRFS_WITHOUT_PARENT; + + fid->objectid = btrfs_ino(BTRFS_I(inode)); + fid->root_objectid = btrfs_root_id(BTRFS_I(inode)->root); + fid->gen = inode->i_generation; + + if (parent) { + u64 parent_root_id; + + fid->parent_objectid = btrfs_ino(BTRFS_I(parent)); + fid->parent_gen = parent->i_generation; + parent_root_id = btrfs_root_id(BTRFS_I(parent)->root); + + if (parent_root_id != fid->root_objectid) { + if (*max_len < BTRFS_FID_SIZE_CONNECTABLE_ROOT) + return FILEID_INVALID; + fid->parent_root_objectid = parent_root_id; + len = BTRFS_FID_SIZE_CONNECTABLE_ROOT; + type = FILEID_BTRFS_WITH_PARENT_ROOT; + } else { + len = BTRFS_FID_SIZE_CONNECTABLE; + type = FILEID_BTRFS_WITH_PARENT; + } + } + + *max_len = len; + return type; +} + +/* + * Read dentry of inode with @objectid from filesystem root @root_objectid. + * + * @sb: the filesystem super block + * @objectid: inode objectid + * @root_objectid: object id of the subvolume root where to look up the inode + * @generation: optional, if not zero, verify that the found inode + * generation matches + * + * Return dentry alias for the inode, otherwise an error. In case the + * generation does not match return ESTALE. + */ +struct dentry *btrfs_get_dentry(struct super_block *sb, u64 objectid, + u64 root_objectid, u64 generation) +{ + struct btrfs_fs_info *fs_info = btrfs_sb(sb); + struct btrfs_root *root; + struct btrfs_inode *inode; + + if (objectid < BTRFS_FIRST_FREE_OBJECTID) + return ERR_PTR(-ESTALE); + + root = btrfs_get_fs_root(fs_info, root_objectid, true); + if (IS_ERR(root)) + return ERR_CAST(root); + + inode = btrfs_iget(objectid, root); + btrfs_put_root(root); + if (IS_ERR(inode)) + return ERR_CAST(inode); + + if (generation != 0 && generation != inode->vfs_inode.i_generation) { + iput(&inode->vfs_inode); + return ERR_PTR(-ESTALE); + } + + return d_obtain_alias(&inode->vfs_inode); +} + +static struct dentry *btrfs_fh_to_parent(struct super_block *sb, struct fid *fh, + int fh_len, int fh_type) +{ + struct btrfs_fid *fid = (struct btrfs_fid *) fh; + u64 objectid, root_objectid; + u32 generation; + + if (fh_type == FILEID_BTRFS_WITH_PARENT) { + if (fh_len < BTRFS_FID_SIZE_CONNECTABLE) + return NULL; + root_objectid = fid->root_objectid; + } else if (fh_type == FILEID_BTRFS_WITH_PARENT_ROOT) { + if (fh_len < BTRFS_FID_SIZE_CONNECTABLE_ROOT) + return NULL; + root_objectid = fid->parent_root_objectid; + } else + return NULL; + + objectid = fid->parent_objectid; + generation = fid->parent_gen; + + return btrfs_get_dentry(sb, objectid, root_objectid, generation); +} + +static struct dentry *btrfs_fh_to_dentry(struct super_block *sb, struct fid *fh, + int fh_len, int fh_type) +{ + struct btrfs_fid *fid = (struct btrfs_fid *) fh; + u64 objectid, root_objectid; + u32 generation; + + if ((fh_type != FILEID_BTRFS_WITH_PARENT || + fh_len < BTRFS_FID_SIZE_CONNECTABLE) && + (fh_type != FILEID_BTRFS_WITH_PARENT_ROOT || + fh_len < BTRFS_FID_SIZE_CONNECTABLE_ROOT) && + (fh_type != FILEID_BTRFS_WITHOUT_PARENT || + fh_len < BTRFS_FID_SIZE_NON_CONNECTABLE)) + return NULL; + + objectid = fid->objectid; + root_objectid = fid->root_objectid; + generation = fid->gen; + + return btrfs_get_dentry(sb, objectid, root_objectid, generation); +} + +struct dentry *btrfs_get_parent(struct dentry *child) +{ + struct btrfs_inode *dir = BTRFS_I(d_inode(child)); + struct btrfs_inode *inode; + struct btrfs_root *root = dir->root; + struct btrfs_fs_info *fs_info = root->fs_info; + struct btrfs_path *path; + struct extent_buffer *leaf; + struct btrfs_root_ref *ref; + struct btrfs_key key; + struct btrfs_key found_key; + int ret; + + path = btrfs_alloc_path(); + if (!path) + return ERR_PTR(-ENOMEM); + + if (btrfs_ino(dir) == BTRFS_FIRST_FREE_OBJECTID) { + key.objectid = btrfs_root_id(root); + key.type = BTRFS_ROOT_BACKREF_KEY; + key.offset = (u64)-1; + root = fs_info->tree_root; + } else { + key.objectid = btrfs_ino(dir); + key.type = BTRFS_INODE_REF_KEY; + key.offset = (u64)-1; + } + + ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); + if (ret < 0) + goto fail; + if (unlikely(ret == 0)) { + /* + * Key with offset of -1 found, there would have to exist an + * inode with such number or a root with such id. + */ + ret = -EUCLEAN; + goto fail; + } + + if (path->slots[0] == 0) { + ret = -ENOENT; + goto fail; + } + + path->slots[0]--; + leaf = path->nodes[0]; + + btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); + if (found_key.objectid != key.objectid || found_key.type != key.type) { + ret = -ENOENT; + goto fail; + } + + if (found_key.type == BTRFS_ROOT_BACKREF_KEY) { + ref = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_root_ref); + key.objectid = btrfs_root_ref_dirid(leaf, ref); + } else { + key.objectid = found_key.offset; + } + btrfs_free_path(path); + + if (found_key.type == BTRFS_ROOT_BACKREF_KEY) { + return btrfs_get_dentry(fs_info->sb, key.objectid, + found_key.offset, 0); + } + + inode = btrfs_iget(key.objectid, root); + if (IS_ERR(inode)) + return ERR_CAST(inode); + + return d_obtain_alias(&inode->vfs_inode); +fail: + btrfs_free_path(path); + return ERR_PTR(ret); +} + +static int btrfs_get_name(struct dentry *parent, char *name, + struct dentry *child) +{ + struct btrfs_inode *inode = BTRFS_I(d_inode(child)); + struct btrfs_inode *dir = BTRFS_I(d_inode(parent)); + struct btrfs_root *root = dir->root; + struct btrfs_fs_info *fs_info = root->fs_info; + BTRFS_PATH_AUTO_FREE(path); + struct btrfs_inode_ref *iref; + struct btrfs_root_ref *rref; + struct extent_buffer *leaf; + unsigned long name_ptr; + struct btrfs_key key; + int name_len; + int ret; + u64 ino; + + if (!S_ISDIR(dir->vfs_inode.i_mode)) + return -EINVAL; + + ino = btrfs_ino(inode); + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + if (ino == BTRFS_FIRST_FREE_OBJECTID) { + key.objectid = btrfs_root_id(inode->root); + key.type = BTRFS_ROOT_BACKREF_KEY; + key.offset = (u64)-1; + root = fs_info->tree_root; + } else { + key.objectid = ino; + key.type = BTRFS_INODE_REF_KEY; + key.offset = btrfs_ino(dir); + } + + ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); + if (ret < 0) { + return ret; + } else if (ret > 0) { + if (ino == BTRFS_FIRST_FREE_OBJECTID) + path->slots[0]--; + else + return -ENOENT; + } + leaf = path->nodes[0]; + + if (ino == BTRFS_FIRST_FREE_OBJECTID) { + rref = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_root_ref); + name_ptr = (unsigned long)(rref + 1); + name_len = btrfs_root_ref_name_len(leaf, rref); + } else { + iref = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_inode_ref); + name_ptr = (unsigned long)(iref + 1); + name_len = btrfs_inode_ref_name_len(leaf, iref); + } + + read_extent_buffer(leaf, name, name_ptr, name_len); + + /* + * have to add the null termination to make sure that reconnect_path + * gets the right len for strlen + */ + name[name_len] = '\0'; + + return 0; +} + +const struct export_operations btrfs_export_ops = { + .encode_fh = btrfs_encode_fh, + .fh_to_dentry = btrfs_fh_to_dentry, + .fh_to_parent = btrfs_fh_to_parent, + .get_parent = btrfs_get_parent, + .get_name = btrfs_get_name, +}; -- cgit v1.3.1