Merge branch 'android-4.4@c71ad0f' into branch 'msm-4.4'

* refs/heads/tmp-c71ad0f:
  BACKPORT: arm64: dts: juno: fix cluster sleep state entry latency on all SoC versions
  staging: android: ashmem: lseek failed due to no FMODE_LSEEK.
  ANDROID: sdcardfs: update module info
  ANDROID: sdcardfs: use d_splice_alias
  ANDROID: sdcardfs: add read_iter/write_iter opeations
  ANDROID: sdcardfs: fix ->llseek to update upper and lower offset
  ANDROID: sdcardfs: copy lower inode attributes in ->ioctl
  ANDROID: sdcardfs: remove unnecessary call to do_munmap
  Merge 4.4.59 into android-4.4
  UPSTREAM: ipv6 addrconf: implement RFC7559 router solicitation backoff
  android: base-cfg: enable CONFIG_INET_DIAG_DESTROY
  ANDROID: android-base.cfg: add CONFIG_MODULES option
  ANDROID: android-base.cfg: add CONFIG_IKCONFIG option
  ANDROID: android-base.cfg: properly sort the file
  ANDROID: binder: add hwbinder,vndbinder to BINDER_DEVICES.
  ANDROID: sort android-recommended.cfg
  UPSTREAM: config/android: Remove CONFIG_IPV6_PRIVACY
  UPSTREAM: config: android: set SELinux as default security mode
  config: android: move device mapper options to recommended
  ANDROID: ARM64: Allow to choose appended kernel image
  UPSTREAM: arm64: vdso: constify vm_special_mapping used for aarch32 vectors page
  UPSTREAM: arm64: vdso: add __init section marker to alloc_vectors_page
  UPSTREAM: ARM: 8597/1: VDSO: put RO and RO after init objects into proper sections
  UPSTREAM: arm64: Add support for CLOCK_MONOTONIC_RAW in clock_gettime() vDSO
  UPSTREAM: arm64: Refactor vDSO time functions
  UPSTREAM: arm64: fix vdso-offsets.h dependency
  UPSTREAM: kbuild: drop FORCE from PHONY targets
  UPSTREAM: mm: add PHYS_PFN, use it in __phys_to_pfn()
  UPSTREAM: ARM: 8476/1: VDSO: use PTR_ERR_OR_ZERO for vma check
  Linux 4.4.58
  crypto: algif_hash - avoid zero-sized array
  fbcon: Fix vc attr at deinit
  serial: 8250_pci: Detach low-level driver during PCI error recovery
  ACPI / blacklist: Make Dell Latitude 3350 ethernet work
  ACPI / blacklist: add _REV quirks for Dell Precision 5520 and 3520
  uvcvideo: uvc_scan_fallback() for webcams with broken chain
  s390/zcrypt: Introduce CEX6 toleration
  block: allow WRITE_SAME commands with the SG_IO ioctl
  vfio/spapr: Postpone allocation of userspace version of TCE table
  PCI: Do any VF BAR updates before enabling the BARs
  PCI: Ignore BAR updates on virtual functions
  PCI: Update BARs using property bits appropriate for type
  PCI: Don't update VF BARs while VF memory space is enabled
  PCI: Decouple IORESOURCE_ROM_ENABLE and PCI_ROM_ADDRESS_ENABLE
  PCI: Add comments about ROM BAR updating
  PCI: Remove pci_resource_bar() and pci_iov_resource_bar()
  PCI: Separate VF BAR updates from standard BAR updates
  x86/hyperv: Handle unknown NMIs on one CPU when unknown_nmi_panic
  igb: add i211 to i210 PHY workaround
  igb: Workaround for igb i210 firmware issue
  xen: do not re-use pirq number cached in pci device msi msg data
  xfs: clear _XBF_PAGES from buffers when readahead page
  USB: usbtmc: add missing endpoint sanity check
  nl80211: fix dumpit error path RTNL deadlocks
  xfs: fix up xfs_swap_extent_forks inline extent handling
  xfs: don't allow di_size with high bit set
  libceph: don't set weight to IN when OSD is destroyed
  raid10: increment write counter after bio is split
  cpufreq: Restore policy min/max limits on CPU online
  ARM: dts: at91: sama5d2: add dma properties to UART nodes
  ARM: at91: pm: cpu_idle: switch DDR to power-down mode
  iommu/vt-d: Fix NULL pointer dereference in device_to_iommu
  xen/acpi: upload PM state from init-domain to Xen
  mmc: sdhci: Do not disable interrupts while waiting for clock
  ext4: mark inode dirty after converting inline directory
  parport: fix attempt to write duplicate procfiles
  iio: hid-sensor-trigger: Change get poll value function order to avoid sensor properties losing after resume from S3
  iio: adc: ti_am335x_adc: fix fifo overrun recovery
  mmc: ushc: fix NULL-deref at probe
  uwb: hwa-rc: fix NULL-deref at probe
  uwb: i1480-dfu: fix NULL-deref at probe
  usb: hub: Fix crash after failure to read BOS descriptor
  usb: musb: cppi41: don't check early-TX-interrupt for Isoch transfer
  USB: wusbcore: fix NULL-deref at probe
  USB: idmouse: fix NULL-deref at probe
  USB: lvtest: fix NULL-deref at probe
  USB: uss720: fix NULL-deref at probe
  usb-core: Add LINEAR_FRAME_INTR_BINTERVAL USB quirk
  usb: gadget: f_uvc: Fix SuperSpeed companion descriptor's wBytesPerInterval
  ACM gadget: fix endianness in notifications
  USB: serial: qcserial: add Dell DW5811e
  USB: serial: option: add Quectel UC15, UC20, EC21, and EC25 modems
  ALSA: hda - Adding a group of pin definition to fix headset problem
  ALSA: ctxfi: Fix the incorrect check of dma_set_mask() call
  ALSA: seq: Fix racy cell insertions during snd_seq_pool_done()
  Input: sur40 - validate number of endpoints before using them
  Input: kbtab - validate number of endpoints before using them
  Input: cm109 - validate number of endpoints before using them
  Input: yealink - validate number of endpoints before using them
  Input: hanwang - validate number of endpoints before using them
  Input: ims-pcu - validate number of endpoints before using them
  Input: iforce - validate number of endpoints before using them
  Input: i8042 - add noloop quirk for Dell Embedded Box PC 3000
  Input: elan_i2c - add ASUS EeeBook X205TA special touchpad fw
  tcp: initialize icsk_ack.lrcvtime at session start time
  socket, bpf: fix sk_filter use after free in sk_clone_lock
  ipv4: provide stronger user input validation in nl_fib_input()
  net: bcmgenet: remove bcmgenet_internal_phy_setup()
  net/mlx5e: Count LRO packets correctly
  net/mlx5: Increase number of max QPs in default profile
  net: unix: properly re-increment inflight counter of GC discarded candidates
  amd-xgbe: Fix jumbo MTU processing on newer hardware
  net: properly release sk_frag.page
  net: bcmgenet: Do not suspend PHY if Wake-on-LAN is enabled
  net/openvswitch: Set the ipv6 source tunnel key address attribute correctly
  Linux 4.4.57
  ext4: fix fencepost in s_first_meta_bg validation
  percpu: acquire pcpu_lock when updating pcpu_nr_empty_pop_pages
  gfs2: Avoid alignment hole in struct lm_lockname
  isdn/gigaset: fix NULL-deref at probe
  target: Fix VERIFY_16 handling in sbc_parse_cdb
  scsi: libiscsi: add lock around task lists to fix list corruption regression
  scsi: lpfc: Add shutdown method for kexec
  target/pscsi: Fix TYPE_TAPE + TYPE_MEDIMUM_CHANGER export
  md/raid1/10: fix potential deadlock
  powerpc/boot: Fix zImage TOC alignment
  cpufreq: Fix and clean up show_cpuinfo_cur_freq()
  perf/core: Fix event inheritance on fork()
  give up on gcc ilog2() constant optimizations
  kernek/fork.c: allocate idle task for a CPU always on its local node
  hv_netvsc: use skb_get_hash() instead of a homegrown implementation
  tpm_tis: Use devm_free_irq not free_irq
  drm/amdgpu: add missing irq.h include
  s390/pci: fix use after free in dma_init
  KVM: PPC: Book3S PR: Fix illegal opcode emulation
  xen/qspinlock: Don't kick CPU if IRQ is not initialized
  Drivers: hv: avoid vfree() on crash
  Drivers: hv: balloon: don't crash when memory is added in non-sorted order
  pinctrl: cherryview: Do not mask all interrupts in probe
  ACPI / video: skip evaluating _DOD when it does not exist
  cxlflash: Increase cmd_per_lun for better throughput
  crypto: mcryptd - Fix load failure
  crypto: cryptd - Assign statesize properly
  crypto: ghash-clmulni - Fix load failure
  USB: don't free bandwidth_mutex too early
  usb: core: hub: hub_port_init lock controller instead of bus
  ANDROID: sdcardfs: Fix style issues in macros
  ANDROID: sdcardfs: Use seq_puts over seq_printf
  ANDROID: sdcardfs: Use to kstrout
  ANDROID: sdcardfs: Use pr_[...] instead of printk
  ANDROID: sdcardfs: remove unneeded null check
  ANDROID: sdcardfs: Fix style issues with comments
  ANDROID: sdcardfs: Fix formatting
  ANDROID: sdcardfs: correct order of descriptors
  fix the deadlock in xt_qtaguid when enable DDEBUG
  net: ipv6: Add sysctl for minimum prefix len acceptable in RIOs.
  Linux 4.4.56
  futex: Add missing error handling to FUTEX_REQUEUE_PI
  futex: Fix potential use-after-free in FUTEX_REQUEUE_PI
  x86/perf: Fix CR4.PCE propagation to use active_mm instead of mm
  x86/kasan: Fix boot with KASAN=y and PROFILE_ANNOTATED_BRANCHES=y
  fscrypto: lock inode while setting encryption policy
  fscrypt: fix renaming and linking special files
  net sched actions: decrement module reference count after table flush.
  dccp: fix memory leak during tear-down of unsuccessful connection request
  dccp/tcp: fix routing redirect race
  bridge: drop netfilter fake rtable unconditionally
  ipv6: avoid write to a possibly cloned skb
  ipv6: make ECMP route replacement less greedy
  mpls: Send route delete notifications when router module is unloaded
  act_connmark: avoid crashing on malformed nlattrs with null parms
  uapi: fix linux/packet_diag.h userspace compilation error
  vrf: Fix use-after-free in vrf_xmit
  dccp: fix use-after-free in dccp_feat_activate_values
  net: fix socket refcounting in skb_complete_tx_timestamp()
  net: fix socket refcounting in skb_complete_wifi_ack()
  tcp: fix various issues for sockets morphing to listen state
  dccp: Unlock sock before calling sk_free()
  net: net_enable_timestamp() can be called from irq contexts
  net: don't call strlen() on the user buffer in packet_bind_spkt()
  l2tp: avoid use-after-free caused by l2tp_ip_backlog_recv
  ipv4: mask tos for input route
  vti6: return GRE_KEY for vti6
  vxlan: correctly validate VXLAN ID against VXLAN_N_VID
  netlink: remove mmapped netlink support
  ANDROID: mmc: core: export emmc revision
  BACKPORT: mmc: core: Export device lifetime information through sysfs
  ANDROID: android-verity: do not compile as independent module
  ANDROID: sched: fix duplicate sched_group_energy const specifiers
  config: disable CONFIG_USELIB and CONFIG_FHANDLE
  ANDROID: power: align wakeup_sources format
  ANDROID: dm: android-verity: allow disable dm-verity for Treble VTS
  uid_sys_stats: change to use rt_mutex
  ANDROID: vfs: user permission2 in notify_change2
  ANDROID: sdcardfs: Fix gid issue
  ANDROID: sdcardfs: Use tabs instead of spaces in multiuser.h
  ANDROID: sdcardfs: Remove uninformative prints
  ANDROID: sdcardfs: move path_put outside of spinlock
  ANDROID: sdcardfs: Use case insensitive hash function
  ANDROID: sdcardfs: declare MODULE_ALIAS_FS
  ANDROID: sdcardfs: Get the blocksize from the lower fs
  ANDROID: sdcardfs: Use d_invalidate instead of drop_recurisve
  ANDROID: sdcardfs: Switch to internal case insensitive compare
  ANDROID: sdcardfs: Use spin_lock_nested
  ANDROID: sdcardfs: Replace get/put with d_lock
  ANDROID: sdcardfs: rate limit warning print
  ANDROID: sdcardfs: Fix case insensitive lookup
  ANDROID: uid_sys_stats: account for fsync syscalls
  ANDROID: sched: add a counter to track fsync
  ANDROID: uid_sys_stats: fix negative write bytes.
  ANDROID: uid_sys_stats: allow writing same state
  ANDROID: uid_sys_stats: rename uid_cputime.c to uid_sys_stats.c
  ANDROID: uid_cputime: add per-uid IO usage accounting
  DTB: Add EAS compatible Juno Energy model to 'juno.dts'
  arm64: dts: juno: Add idle-states to device tree
  ANDROID: Replace spaces by '_' for some android filesystem tracepoints.
  usb: gadget: f_accessory: Fix for UsbAccessory clean unbind.
  android: binder: move global binder state into context struct.
  android: binder: add padding to binder_fd_array_object.
  binder: use group leader instead of open thread
  nf: IDLETIMER: Use fullsock when querying uid
  nf: IDLETIMER: Fix use after free condition during work
  ANDROID: dm: android-verity: fix table_make_digest() error handling
  ANDROID: usb: gadget: function: Fix commenting style
  cpufreq: interactive governor drops bits in time calculation
  ANDROID: sdcardfs: support direct-IO (DIO) operations
  ANDROID: sdcardfs: implement vm_ops->page_mkwrite
  ANDROID: sdcardfs: Don't bother deleting freelist
  ANDROID: sdcardfs: Add missing path_put
  ANDROID: sdcardfs: Fix incorrect hash
  ANDROID: ext4 crypto: Disables zeroing on truncation when there's no key
  ANDROID: ext4: add a non-reversible key derivation method
  ANDROID: ext4: allow encrypting filenames using HEH algorithm
  ANDROID: arm64/crypto: add ARMv8-CE optimized poly_hash algorithm
  ANDROID: crypto: heh - factor out poly_hash algorithm
  ANDROID: crypto: heh - Add Hash-Encrypt-Hash (HEH) algorithm
  ANDROID: crypto: gf128mul - Add ble multiplication functions
  ANDROID: crypto: gf128mul - Refactor gf128 overflow macros and tables
  UPSTREAM: crypto: gf128mul - Zero memory when freeing multiplication table
  ANDROID: crypto: shash - Add crypto_grab_shash() and crypto_spawn_shash_alg()
  ANDROID: crypto: allow blkcipher walks over ablkcipher data
  UPSTREAM: arm/arm64: crypto: assure that ECB modes don't require an IV
  ANDROID: Refactor fs readpage/write tracepoints.
  ANDROID: export security_path_chown
  Squashfs: optimize reading uncompressed data
  Squashfs: implement .readpages()
  Squashfs: replace buffer_head with BIO
  Squashfs: refactor page_actor
  Squashfs: remove the FILE_CACHE option
  ANDROID: android-recommended.cfg: CONFIG_CPU_SW_DOMAIN_PAN=y
  FROMLIST: 9p: fix a potential acl leak
  BACKPORT: posix_acl: Clear SGID bit when setting file permissions
  UPSTREAM: udp: properly support MSG_PEEK with truncated buffers
  UPSTREAM: arm64: Allow hw watchpoint of length 3,5,6 and 7
  BACKPORT: arm64: hw_breakpoint: Handle inexact watchpoint addresses
  UPSTREAM: arm64: Allow hw watchpoint at varied offset from base address
  BACKPORT: hw_breakpoint: Allow watchpoint of length 3,5,6 and 7
  ANDROID: sdcardfs: Switch strcasecmp for internal call
  ANDROID: sdcardfs: switch to full_name_hash and qstr
  ANDROID: sdcardfs: Add GID Derivation to sdcardfs
  ANDROID: sdcardfs: Remove redundant operation
  ANDROID: sdcardfs: add support for user permission isolation
  ANDROID: sdcardfs: Refactor configfs interface
  ANDROID: sdcardfs: Allow non-owners to touch
  ANDROID: binder: fix format specifier for type binder_size_t
  ANDROID: fs: Export vfs_rmdir2
  ANDROID: fs: Export free_fs_struct and set_fs_pwd
  BACKPORT: Input: xpad - validate USB endpoint count during probe
  BACKPORT: Input: xpad - fix oops when attaching an unknown Xbox One gamepad
  ANDROID: mnt: remount should propagate to slaves of slaves
  ANDROID: sdcardfs: Switch ->d_inode to d_inode()
  ANDROID: sdcardfs: Fix locking issue with permision fix up
  ANDROID: sdcardfs: Change magic value
  ANDROID: sdcardfs: Use per mount permissions
  ANDROID: sdcardfs: Add gid and mask to private mount data
  ANDROID: sdcardfs: User new permission2 functions
  ANDROID: vfs: Add setattr2 for filesystems with per mount permissions
  ANDROID: vfs: Add permission2 for filesystems with per mount permissions
  ANDROID: vfs: Allow filesystems to access their private mount data
  ANDROID: mnt: Add filesystem private data to mount points
  ANDROID: sdcardfs: Move directory unlock before touch
  ANDROID: sdcardfs: fix external storage exporting incorrect uid
  ANDROID: sdcardfs: Added top to sdcardfs_inode_info
  ANDROID: sdcardfs: Switch package list to RCU
  ANDROID: sdcardfs: Fix locking for permission fix up
  ANDROID: sdcardfs: Check for other cases on path lookup
  ANDROID: sdcardfs: override umask on mkdir and create
  arm64: kernel: Fix build warning
  DEBUG: sched/fair: Fix sched_load_avg_cpu events for task_groups
  DEBUG: sched/fair: Fix missing sched_load_avg_cpu events
  UPSTREAM: l2tp: fix racy SOCK_ZAPPED flag check in l2tp_ip{,6}_bind()
  UPSTREAM: packet: fix race condition in packet_set_ring
  UPSTREAM: netlink: Fix dump skb leak/double free
  UPSTREAM: net: avoid signed overflows for SO_{SND|RCV}BUFFORCE
  MIPS: Prevent "restoration" of MSA context in non-MSA kernels
  net: socket: don't set sk_uid to garbage value in ->setattr()
  ANDROID: configs: CONFIG_ARM64_SW_TTBR0_PAN=y
  UPSTREAM: arm64: Disable PAN on uaccess_enable()
  UPSTREAM: arm64: Enable CONFIG_ARM64_SW_TTBR0_PAN
  UPSTREAM: arm64: xen: Enable user access before a privcmd hvc call
  UPSTREAM: arm64: Handle faults caused by inadvertent user access with PAN enabled
  BACKPORT: arm64: Disable TTBR0_EL1 during normal kernel execution
  BACKPORT: arm64: Introduce uaccess_{disable,enable} functionality based on TTBR0_EL1
  BACKPORT: arm64: Factor out TTBR0_EL1 post-update workaround into a specific asm macro
  BACKPORT: arm64: Factor out PAN enabling/disabling into separate uaccess_* macros
  UPSTREAM: arm64: alternative: add auto-nop infrastructure
  UPSTREAM: arm64: barriers: introduce nops and __nops macros for NOP sequences
  Revert "FROMLIST: arm64: Factor out PAN enabling/disabling into separate uaccess_* macros"
  Revert "FROMLIST: arm64: Factor out TTBR0_EL1 post-update workaround into a specific asm macro"
  Revert "FROMLIST: arm64: Introduce uaccess_{disable,enable} functionality based on TTBR0_EL1"
  Revert "FROMLIST: arm64: Disable TTBR0_EL1 during normal kernel execution"
  Revert "FROMLIST: arm64: Handle faults caused by inadvertent user access with PAN enabled"
  Revert "FROMLIST: arm64: xen: Enable user access before a privcmd hvc call"
  Revert "FROMLIST: arm64: Enable CONFIG_ARM64_SW_TTBR0_PAN"
  ANDROID: sched/walt: fix build failure if FAIR_GROUP_SCHED=n
  ANDROID: trace: net: use %pK for kernel pointers
  ANDROID: android-base: Enable QUOTA related configs
  net: ipv4: Don't crash if passing a null sk to ip_rt_update_pmtu.
  net: inet: Support UID-based routing in IP protocols.
  net: core: add UID to flows, rules, and routes
  net: core: Add a UID field to struct sock.
  Revert "net: core: Support UID-based routing."
  UPSTREAM: efi/arm64: Don't apply MEMBLOCK_NOMAP to UEFI memory map mapping
  UPSTREAM: arm64: mm: always take dirty state from new pte in ptep_set_access_flags
  UPSTREAM: arm64: Implement pmdp_set_access_flags() for hardware AF/DBM
  UPSTREAM: arm64: Fix typo in the pmdp_huge_get_and_clear() definition
  UPSTREAM: arm64: enable CONFIG_DEBUG_RODATA by default
  goldfish: enable CONFIG_INET_DIAG_DESTROY
  sched/walt: kill {min,max}_capacity
  sched: fix wrong truncation of walt_avg
  build: fix build config kernel_dir
  ANDROID: dm verity: add minimum prefetch size
  build: add build server configs for goldfish
  usb: gadget: Fix compilation problem with tx_qlen field

Conflicts:
	android/configs/android-base.cfg
	arch/arm64/Makefile
	arch/arm64/include/asm/cpufeature.h
	arch/arm64/kernel/vdso/gettimeofday.S
	arch/arm64/mm/cache.S
	drivers/md/Kconfig
	drivers/misc/Makefile
	drivers/mmc/host/sdhci.c
	drivers/usb/core/hcd.c
	drivers/usb/gadget/function/u_ether.c
	fs/sdcardfs/derived_perm.c
	fs/sdcardfs/file.c
	fs/sdcardfs/inode.c
	fs/sdcardfs/lookup.c
	fs/sdcardfs/main.c
	fs/sdcardfs/multiuser.h
	fs/sdcardfs/packagelist.c
	fs/sdcardfs/sdcardfs.h
	fs/sdcardfs/super.c
	include/linux/mmc/card.h
	include/linux/mmc/mmc.h
	include/trace/events/android_fs.h
	include/trace/events/android_fs_template.h
	drivers/android/binder.c
	fs/exec.c
	fs/ext4/crypto_key.c
	fs/ext4/ext4.h
	fs/ext4/inline.c
	fs/ext4/inode.c
	fs/ext4/readpage.c
	fs/f2fs/data.c
	fs/f2fs/inline.c
	fs/mpage.c
	include/linux/dcache.h
	include/trace/events/sched.h
	include/uapi/linux/ipv6.h
	net/ipv4/tcp_ipv4.c
	net/netfilter/xt_IDLETIMER.c

Change-Id: Ie345db6a14869fe0aa794aef4b71b5d0d503690b
Signed-off-by: Blagovest Kolenichev <bkolenichev@codeaurora.org>

1 files changed, 114 insertions, 131 deletions

diff --git a/fs/squashfs/file_direct.c b/fs/squashfs/file_direct.c
index 43e7a7eddac0..c97af4c6ccd0 100644
--- a/fs/squashfs/file_direct.c
+++ b/fs/squashfs/file_direct.c
@@ -13,6 +13,7 @@
 #include <linux/string.h>
 #include <linux/pagemap.h>
 #include <linux/mutex.h>
+#include <linux/mm_inline.h>
 
 #include "squashfs_fs.h"
 #include "squashfs_fs_sb.h"
@@ -20,157 +21,139 @@
 #include "squashfs.h"
 #include "page_actor.h"
 
-static int squashfs_read_cache(struct page *target_page, u64 block, int bsize,
-	int pages, struct page **page);
-
-/* Read separately compressed datablock directly into page cache */
-int squashfs_readpage_block(struct page *target_page, u64 block, int bsize)
+// Backported from 4.5
+#define lru_to_page(head) (list_entry((head)->prev, struct page, lru))
 
+static void release_actor_pages(struct page **page, int pages, int error)
 {
-	struct inode *inode = target_page->mapping->host;
-	struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info;
+	int i;
 
-	int file_end = (i_size_read(inode) - 1) >> PAGE_CACHE_SHIFT;
-	int mask = (1 << (msblk->block_log - PAGE_CACHE_SHIFT)) - 1;
-	int start_index = target_page->index & ~mask;
-	int end_index = start_index | mask;
-	int i, n, pages, missing_pages, bytes, res = -ENOMEM;
+	for (i = 0; i < pages; i++) {
+		if (!page[i])
+			continue;
+		flush_dcache_page(page[i]);
+		if (!error)
+			SetPageUptodate(page[i]);
+		else {
+			SetPageError(page[i]);
+			zero_user_segment(page[i], 0, PAGE_CACHE_SIZE);
+		}
+		unlock_page(page[i]);
+		put_page(page[i]);
+	}
+	kfree(page);
+}
+
+/*
+ * Create a "page actor" which will kmap and kunmap the
+ * page cache pages appropriately within the decompressor
+ */
+static struct squashfs_page_actor *actor_from_page_cache(
+	unsigned int actor_pages, struct page *target_page,
+	struct list_head *rpages, unsigned int *nr_pages, int start_index,
+	struct address_space *mapping)
+{
 	struct page **page;
 	struct squashfs_page_actor *actor;
-	void *pageaddr;
-
-	if (end_index > file_end)
-		end_index = file_end;
-
-	pages = end_index - start_index + 1;
-
-	page = kmalloc_array(pages, sizeof(void *), GFP_KERNEL);
-	if (page == NULL)
-		return res;
-
-	/*
-	 * Create a "page actor" which will kmap and kunmap the
-	 * page cache pages appropriately within the decompressor
-	 */
-	actor = squashfs_page_actor_init_special(page, pages, 0);
-	if (actor == NULL)
-		goto out;
-
-	/* Try to grab all the pages covered by the Squashfs block */
-	for (missing_pages = 0, i = 0, n = start_index; i < pages; i++, n++) {
-		page[i] = (n == target_page->index) ? target_page :
-			grab_cache_page_nowait(target_page->mapping, n);
+	int i, n;
+	gfp_t gfp = mapping_gfp_constraint(mapping, GFP_KERNEL);
+
+	page = kmalloc_array(actor_pages, sizeof(void *), GFP_KERNEL);
+	if (!page)
+		return NULL;
+
+	for (i = 0, n = start_index; i < actor_pages; i++, n++) {
+		if (target_page == NULL && rpages && !list_empty(rpages)) {
+			struct page *cur_page = lru_to_page(rpages);
+
+			if (cur_page->index < start_index + actor_pages) {
+				list_del(&cur_page->lru);
+				--(*nr_pages);
+				if (add_to_page_cache_lru(cur_page, mapping,
+							  cur_page->index, gfp))
+					put_page(cur_page);
+				else
+					target_page = cur_page;
+			} else
+				rpages = NULL;
+		}
 
-		if (page[i] == NULL) {
-			missing_pages++;
-			continue;
+		if (target_page && target_page->index == n) {
+			page[i] = target_page;
+			target_page = NULL;
+		} else {
+			page[i] = grab_cache_page_nowait(mapping, n);
+			if (page[i] == NULL)
+				continue;
 		}
 
 		if (PageUptodate(page[i])) {
 			unlock_page(page[i]);
-			page_cache_release(page[i]);
+			put_page(page[i]);
 			page[i] = NULL;
-			missing_pages++;
 		}
 	}
 
-	if (missing_pages) {
-		/*
-		 * Couldn't get one or more pages, this page has either
-		 * been VM reclaimed, but others are still in the page cache
-		 * and uptodate, or we're racing with another thread in
-		 * squashfs_readpage also trying to grab them.  Fall back to
-		 * using an intermediate buffer.
-		 */
-		res = squashfs_read_cache(target_page, block, bsize, pages,
-								page);
-		if (res < 0)
-			goto mark_errored;
-
-		goto out;
+	actor = squashfs_page_actor_init(page, actor_pages, 0,
+			release_actor_pages);
+	if (!actor) {
+		release_actor_pages(page, actor_pages, -ENOMEM);
+		kfree(page);
+		return NULL;
 	}
-
-	/* Decompress directly into the page cache buffers */
-	res = squashfs_read_data(inode->i_sb, block, bsize, NULL, actor);
-	if (res < 0)
-		goto mark_errored;
-
-	/* Last page may have trailing bytes not filled */
-	bytes = res % PAGE_CACHE_SIZE;
-	if (bytes) {
-		pageaddr = kmap_atomic(page[pages - 1]);
-		memset(pageaddr + bytes, 0, PAGE_CACHE_SIZE - bytes);
-		kunmap_atomic(pageaddr);
-	}
-
-	/* Mark pages as uptodate, unlock and release */
-	for (i = 0; i < pages; i++) {
-		flush_dcache_page(page[i]);
-		SetPageUptodate(page[i]);
-		unlock_page(page[i]);
-		if (page[i] != target_page)
-			page_cache_release(page[i]);
-	}
-
-	kfree(actor);
-	kfree(page);
-
-	return 0;
-
-mark_errored:
-	/* Decompression failed, mark pages as errored.  Target_page is
-	 * dealt with by the caller
-	 */
-	for (i = 0; i < pages; i++) {
-		if (page[i] == NULL || page[i] == target_page)
-			continue;
-		flush_dcache_page(page[i]);
-		SetPageError(page[i]);
-		unlock_page(page[i]);
-		page_cache_release(page[i]);
-	}
-
-out:
-	kfree(actor);
-	kfree(page);
-	return res;
+	return actor;
 }
 
+int squashfs_readpages_block(struct page *target_page,
+			     struct list_head *readahead_pages,
+			     unsigned int *nr_pages,
+			     struct address_space *mapping,
+			     int page_index, u64 block, int bsize)
 
-static int squashfs_read_cache(struct page *target_page, u64 block, int bsize,
-	int pages, struct page **page)
 {
-	struct inode *i = target_page->mapping->host;
-	struct squashfs_cache_entry *buffer = squashfs_get_datablock(i->i_sb,
-						 block, bsize);
-	int bytes = buffer->length, res = buffer->error, n, offset = 0;
-	void *pageaddr;
-
-	if (res) {
-		ERROR("Unable to read page, block %llx, size %x\n", block,
-			bsize);
-		goto out;
-	}
-
-	for (n = 0; n < pages && bytes > 0; n++,
-			bytes -= PAGE_CACHE_SIZE, offset += PAGE_CACHE_SIZE) {
-		int avail = min_t(int, bytes, PAGE_CACHE_SIZE);
-
-		if (page[n] == NULL)
-			continue;
+	struct squashfs_page_actor *actor;
+	struct inode *inode = mapping->host;
+	struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info;
+	int start_index, end_index, file_end, actor_pages, res;
+	int mask = (1 << (msblk->block_log - PAGE_CACHE_SHIFT)) - 1;
 
-		pageaddr = kmap_atomic(page[n]);
-		squashfs_copy_data(pageaddr, buffer, offset, avail);
-		memset(pageaddr + avail, 0, PAGE_CACHE_SIZE - avail);
-		kunmap_atomic(pageaddr);
-		flush_dcache_page(page[n]);
-		SetPageUptodate(page[n]);
-		unlock_page(page[n]);
-		if (page[n] != target_page)
-			page_cache_release(page[n]);
+	/*
+	 * If readpage() is called on an uncompressed datablock, we can just
+	 * read the pages instead of fetching the whole block.
+	 * This greatly improves the performance when a process keep doing
+	 * random reads because we only fetch the necessary data.
+	 * The readahead algorithm will take care of doing speculative reads
+	 * if necessary.
+	 * We can't read more than 1 block even if readahead provides use more
+	 * pages because we don't know yet if the next block is compressed or
+	 * not.
+	 */
+	if (bsize && !SQUASHFS_COMPRESSED_BLOCK(bsize)) {
+		u64 block_end = block + msblk->block_size;
+
+		block += (page_index & mask) * PAGE_CACHE_SIZE;
+		actor_pages = (block_end - block) / PAGE_CACHE_SIZE;
+		if (*nr_pages < actor_pages)
+			actor_pages = *nr_pages;
+		start_index = page_index;
+		bsize = min_t(int, bsize, (PAGE_CACHE_SIZE * actor_pages)
+					  | SQUASHFS_COMPRESSED_BIT_BLOCK);
+	} else {
+		file_end = (i_size_read(inode) - 1) >> PAGE_CACHE_SHIFT;
+		start_index = page_index & ~mask;
+		end_index = start_index | mask;
+		if (end_index > file_end)
+			end_index = file_end;
+		actor_pages = end_index - start_index + 1;
 	}
 
-out:
-	squashfs_cache_put(buffer);
-	return res;
+	actor = actor_from_page_cache(actor_pages, target_page,
+				      readahead_pages, nr_pages, start_index,
+				      mapping);
+	if (!actor)
+		return -ENOMEM;
+
+	res = squashfs_read_data_async(inode->i_sb, block, bsize, NULL,
+				       actor);
+	return res < 0 ? res : 0;
 }