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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /fs/vboxsf/file.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to 'fs/vboxsf/file.c')
-rw-r--r--fs/vboxsf/file.c397
1 files changed, 397 insertions, 0 deletions
diff --git a/fs/vboxsf/file.c b/fs/vboxsf/file.c
new file mode 100644
index 000000000..572aa1c43
--- /dev/null
+++ b/fs/vboxsf/file.c
@@ -0,0 +1,397 @@
+// SPDX-License-Identifier: MIT
+/*
+ * VirtualBox Guest Shared Folders support: Regular file inode and file ops.
+ *
+ * Copyright (C) 2006-2018 Oracle Corporation
+ */
+
+#include <linux/mm.h>
+#include <linux/page-flags.h>
+#include <linux/pagemap.h>
+#include <linux/highmem.h>
+#include <linux/sizes.h>
+#include "vfsmod.h"
+
+struct vboxsf_handle {
+ u64 handle;
+ u32 root;
+ u32 access_flags;
+ struct kref refcount;
+ struct list_head head;
+};
+
+struct vboxsf_handle *vboxsf_create_sf_handle(struct inode *inode,
+ u64 handle, u32 access_flags)
+{
+ struct vboxsf_inode *sf_i = VBOXSF_I(inode);
+ struct vboxsf_handle *sf_handle;
+
+ sf_handle = kmalloc(sizeof(*sf_handle), GFP_KERNEL);
+ if (!sf_handle)
+ return ERR_PTR(-ENOMEM);
+
+ /* the host may have given us different attr then requested */
+ sf_i->force_restat = 1;
+
+ /* init our handle struct and add it to the inode's handles list */
+ sf_handle->handle = handle;
+ sf_handle->root = VBOXSF_SBI(inode->i_sb)->root;
+ sf_handle->access_flags = access_flags;
+ kref_init(&sf_handle->refcount);
+
+ mutex_lock(&sf_i->handle_list_mutex);
+ list_add(&sf_handle->head, &sf_i->handle_list);
+ mutex_unlock(&sf_i->handle_list_mutex);
+
+ return sf_handle;
+}
+
+static int vboxsf_file_open(struct inode *inode, struct file *file)
+{
+ struct vboxsf_sbi *sbi = VBOXSF_SBI(inode->i_sb);
+ struct shfl_createparms params = {};
+ struct vboxsf_handle *sf_handle;
+ u32 access_flags = 0;
+ int err;
+
+ /*
+ * We check the value of params.handle afterwards to find out if
+ * the call succeeded or failed, as the API does not seem to cleanly
+ * distinguish error and informational messages.
+ *
+ * Furthermore, we must set params.handle to SHFL_HANDLE_NIL to
+ * make the shared folders host service use our mode parameter.
+ */
+ params.handle = SHFL_HANDLE_NIL;
+ if (file->f_flags & O_CREAT) {
+ params.create_flags |= SHFL_CF_ACT_CREATE_IF_NEW;
+ /*
+ * We ignore O_EXCL, as the Linux kernel seems to call create
+ * beforehand itself, so O_EXCL should always fail.
+ */
+ if (file->f_flags & O_TRUNC)
+ params.create_flags |= SHFL_CF_ACT_OVERWRITE_IF_EXISTS;
+ else
+ params.create_flags |= SHFL_CF_ACT_OPEN_IF_EXISTS;
+ } else {
+ params.create_flags |= SHFL_CF_ACT_FAIL_IF_NEW;
+ if (file->f_flags & O_TRUNC)
+ params.create_flags |= SHFL_CF_ACT_OVERWRITE_IF_EXISTS;
+ }
+
+ switch (file->f_flags & O_ACCMODE) {
+ case O_RDONLY:
+ access_flags |= SHFL_CF_ACCESS_READ;
+ break;
+
+ case O_WRONLY:
+ access_flags |= SHFL_CF_ACCESS_WRITE;
+ break;
+
+ case O_RDWR:
+ access_flags |= SHFL_CF_ACCESS_READWRITE;
+ break;
+
+ default:
+ WARN_ON(1);
+ }
+
+ if (file->f_flags & O_APPEND)
+ access_flags |= SHFL_CF_ACCESS_APPEND;
+
+ params.create_flags |= access_flags;
+ params.info.attr.mode = inode->i_mode;
+
+ err = vboxsf_create_at_dentry(file_dentry(file), &params);
+ if (err == 0 && params.handle == SHFL_HANDLE_NIL)
+ err = (params.result == SHFL_FILE_EXISTS) ? -EEXIST : -ENOENT;
+ if (err)
+ return err;
+
+ sf_handle = vboxsf_create_sf_handle(inode, params.handle, access_flags);
+ if (IS_ERR(sf_handle)) {
+ vboxsf_close(sbi->root, params.handle);
+ return PTR_ERR(sf_handle);
+ }
+
+ file->private_data = sf_handle;
+ return 0;
+}
+
+static void vboxsf_handle_release(struct kref *refcount)
+{
+ struct vboxsf_handle *sf_handle =
+ container_of(refcount, struct vboxsf_handle, refcount);
+
+ vboxsf_close(sf_handle->root, sf_handle->handle);
+ kfree(sf_handle);
+}
+
+void vboxsf_release_sf_handle(struct inode *inode, struct vboxsf_handle *sf_handle)
+{
+ struct vboxsf_inode *sf_i = VBOXSF_I(inode);
+
+ mutex_lock(&sf_i->handle_list_mutex);
+ list_del(&sf_handle->head);
+ mutex_unlock(&sf_i->handle_list_mutex);
+
+ kref_put(&sf_handle->refcount, vboxsf_handle_release);
+}
+
+static int vboxsf_file_release(struct inode *inode, struct file *file)
+{
+ /*
+ * When a file is closed on our (the guest) side, we want any subsequent
+ * accesses done on the host side to see all changes done from our side.
+ */
+ filemap_write_and_wait(inode->i_mapping);
+
+ vboxsf_release_sf_handle(inode, file->private_data);
+ return 0;
+}
+
+/*
+ * Write back dirty pages now, because there may not be any suitable
+ * open files later
+ */
+static void vboxsf_vma_close(struct vm_area_struct *vma)
+{
+ filemap_write_and_wait(vma->vm_file->f_mapping);
+}
+
+static const struct vm_operations_struct vboxsf_file_vm_ops = {
+ .close = vboxsf_vma_close,
+ .fault = filemap_fault,
+ .map_pages = filemap_map_pages,
+};
+
+static int vboxsf_file_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ int err;
+
+ err = generic_file_mmap(file, vma);
+ if (!err)
+ vma->vm_ops = &vboxsf_file_vm_ops;
+
+ return err;
+}
+
+/*
+ * Note that since we are accessing files on the host's filesystem, files
+ * may always be changed underneath us by the host!
+ *
+ * The vboxsf API between the guest and the host does not offer any functions
+ * to deal with this. There is no inode-generation to check for changes, no
+ * events / callback on changes and no way to lock files.
+ *
+ * To avoid returning stale data when a file gets *opened* on our (the guest)
+ * side, we do a "stat" on the host side, then compare the mtime with the
+ * last known mtime and invalidate the page-cache if they differ.
+ * This is done from vboxsf_inode_revalidate().
+ *
+ * When reads are done through the read_iter fop, it is possible to do
+ * further cache revalidation then, there are 3 options to deal with this:
+ *
+ * 1) Rely solely on the revalidation done at open time
+ * 2) Do another "stat" and compare mtime again. Unfortunately the vboxsf
+ * host API does not allow stat on handles, so we would need to use
+ * file->f_path.dentry and the stat will then fail if the file was unlinked
+ * or renamed (and there is no thing like NFS' silly-rename). So we get:
+ * 2a) "stat" and compare mtime, on stat failure invalidate the cache
+ * 2b) "stat" and compare mtime, on stat failure do nothing
+ * 3) Simply always call invalidate_inode_pages2_range on the range of the read
+ *
+ * Currently we are keeping things KISS and using option 1. this allows
+ * directly using generic_file_read_iter without wrapping it.
+ *
+ * This means that only data written on the host side before open() on
+ * the guest side is guaranteed to be seen by the guest. If necessary
+ * we may provide other read-cache strategies in the future and make this
+ * configurable through a mount option.
+ */
+const struct file_operations vboxsf_reg_fops = {
+ .llseek = generic_file_llseek,
+ .read_iter = generic_file_read_iter,
+ .write_iter = generic_file_write_iter,
+ .mmap = vboxsf_file_mmap,
+ .open = vboxsf_file_open,
+ .release = vboxsf_file_release,
+ .fsync = noop_fsync,
+ .splice_read = generic_file_splice_read,
+};
+
+const struct inode_operations vboxsf_reg_iops = {
+ .getattr = vboxsf_getattr,
+ .setattr = vboxsf_setattr
+};
+
+static int vboxsf_read_folio(struct file *file, struct folio *folio)
+{
+ struct page *page = &folio->page;
+ struct vboxsf_handle *sf_handle = file->private_data;
+ loff_t off = page_offset(page);
+ u32 nread = PAGE_SIZE;
+ u8 *buf;
+ int err;
+
+ buf = kmap(page);
+
+ err = vboxsf_read(sf_handle->root, sf_handle->handle, off, &nread, buf);
+ if (err == 0) {
+ memset(&buf[nread], 0, PAGE_SIZE - nread);
+ flush_dcache_page(page);
+ SetPageUptodate(page);
+ } else {
+ SetPageError(page);
+ }
+
+ kunmap(page);
+ unlock_page(page);
+ return err;
+}
+
+static struct vboxsf_handle *vboxsf_get_write_handle(struct vboxsf_inode *sf_i)
+{
+ struct vboxsf_handle *h, *sf_handle = NULL;
+
+ mutex_lock(&sf_i->handle_list_mutex);
+ list_for_each_entry(h, &sf_i->handle_list, head) {
+ if (h->access_flags == SHFL_CF_ACCESS_WRITE ||
+ h->access_flags == SHFL_CF_ACCESS_READWRITE) {
+ kref_get(&h->refcount);
+ sf_handle = h;
+ break;
+ }
+ }
+ mutex_unlock(&sf_i->handle_list_mutex);
+
+ return sf_handle;
+}
+
+static int vboxsf_writepage(struct page *page, struct writeback_control *wbc)
+{
+ struct inode *inode = page->mapping->host;
+ struct vboxsf_inode *sf_i = VBOXSF_I(inode);
+ struct vboxsf_handle *sf_handle;
+ loff_t off = page_offset(page);
+ loff_t size = i_size_read(inode);
+ u32 nwrite = PAGE_SIZE;
+ u8 *buf;
+ int err;
+
+ if (off + PAGE_SIZE > size)
+ nwrite = size & ~PAGE_MASK;
+
+ sf_handle = vboxsf_get_write_handle(sf_i);
+ if (!sf_handle)
+ return -EBADF;
+
+ buf = kmap(page);
+ err = vboxsf_write(sf_handle->root, sf_handle->handle,
+ off, &nwrite, buf);
+ kunmap(page);
+
+ kref_put(&sf_handle->refcount, vboxsf_handle_release);
+
+ if (err == 0) {
+ ClearPageError(page);
+ /* mtime changed */
+ sf_i->force_restat = 1;
+ } else {
+ ClearPageUptodate(page);
+ }
+
+ unlock_page(page);
+ return err;
+}
+
+static int vboxsf_write_end(struct file *file, struct address_space *mapping,
+ loff_t pos, unsigned int len, unsigned int copied,
+ struct page *page, void *fsdata)
+{
+ struct inode *inode = mapping->host;
+ struct vboxsf_handle *sf_handle = file->private_data;
+ unsigned int from = pos & ~PAGE_MASK;
+ u32 nwritten = len;
+ u8 *buf;
+ int err;
+
+ /* zero the stale part of the page if we did a short copy */
+ if (!PageUptodate(page) && copied < len)
+ zero_user(page, from + copied, len - copied);
+
+ buf = kmap(page);
+ err = vboxsf_write(sf_handle->root, sf_handle->handle,
+ pos, &nwritten, buf + from);
+ kunmap(page);
+
+ if (err) {
+ nwritten = 0;
+ goto out;
+ }
+
+ /* mtime changed */
+ VBOXSF_I(inode)->force_restat = 1;
+
+ if (!PageUptodate(page) && nwritten == PAGE_SIZE)
+ SetPageUptodate(page);
+
+ pos += nwritten;
+ if (pos > inode->i_size)
+ i_size_write(inode, pos);
+
+out:
+ unlock_page(page);
+ put_page(page);
+
+ return nwritten;
+}
+
+/*
+ * Note simple_write_begin does not read the page from disk on partial writes
+ * this is ok since vboxsf_write_end only writes the written parts of the
+ * page and it does not call SetPageUptodate for partial writes.
+ */
+const struct address_space_operations vboxsf_reg_aops = {
+ .read_folio = vboxsf_read_folio,
+ .writepage = vboxsf_writepage,
+ .dirty_folio = filemap_dirty_folio,
+ .write_begin = simple_write_begin,
+ .write_end = vboxsf_write_end,
+};
+
+static const char *vboxsf_get_link(struct dentry *dentry, struct inode *inode,
+ struct delayed_call *done)
+{
+ struct vboxsf_sbi *sbi = VBOXSF_SBI(inode->i_sb);
+ struct shfl_string *path;
+ char *link;
+ int err;
+
+ if (!dentry)
+ return ERR_PTR(-ECHILD);
+
+ path = vboxsf_path_from_dentry(sbi, dentry);
+ if (IS_ERR(path))
+ return ERR_CAST(path);
+
+ link = kzalloc(PATH_MAX, GFP_KERNEL);
+ if (!link) {
+ __putname(path);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ err = vboxsf_readlink(sbi->root, path, PATH_MAX, link);
+ __putname(path);
+ if (err) {
+ kfree(link);
+ return ERR_PTR(err);
+ }
+
+ set_delayed_call(done, kfree_link, link);
+ return link;
+}
+
+const struct inode_operations vboxsf_lnk_iops = {
+ .get_link = vboxsf_get_link
+};