/* Filesystem index definition * * Copyright (C) 2004-2007 Red Hat, Inc. All Rights Reserved. * Written by David Howells (dhowells@redhat.com) * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ #define FSCACHE_DEBUG_LEVEL CACHE #include #include "internal.h" static uint16_t fscache_fsdef_netfs_get_key(const void *cookie_netfs_data, void *buffer, uint16_t bufmax); static uint16_t fscache_fsdef_netfs_get_aux(const void *cookie_netfs_data, void *buffer, uint16_t bufmax); static enum fscache_checkaux fscache_fsdef_netfs_check_aux(void *cookie_netfs_data, const void *data, uint16_t datalen); /* * The root index is owned by FS-Cache itself. * * When a netfs requests caching facilities, FS-Cache will, if one doesn't * already exist, create an entry in the root index with the key being the name * of the netfs ("AFS" for example), and the auxiliary data holding the index * structure version supplied by the netfs: * * FSDEF * | * +-----------+ * | | * NFS AFS * [v=1] [v=1] * * If an entry with the appropriate name does already exist, the version is * compared. If the version is different, the entire subtree from that entry * will be discarded and a new entry created. * * The new entry will be an index, and a cookie referring to it will be passed * to the netfs. This is then the root handle by which the netfs accesses the * cache. It can create whatever objects it likes in that index, including * further indices. */ static struct fscache_cookie_def fscache_fsdef_index_def = { .name = ".FS-Cache", .type = FSCACHE_COOKIE_TYPE_INDEX, }; struct fscache_cookie fscache_fsdef_index = { .usage = ATOMIC_INIT(1), .n_active = ATOMIC_INIT(1), .lock = __SPIN_LOCK_UNLOCKED(fscache_fsdef_index.lock), .backing_objects = HLIST_HEAD_INIT, .def = &fscache_fsdef_index_def, .flags = 1 << FSCACHE_COOKIE_ENABLED, }; EXPORT_SYMBOL(fscache_fsdef_index); /* * Definition of an entry in the root index. Each entry is an index, keyed to * a specific netfs and only applicable to a particular version of the index * structure used by that netfs. */ struct fscache_cookie_def fscache_fsdef_netfs_def = { .name = "FSDEF.netfs", .type = FSCACHE_COOKIE_TYPE_INDEX, .get_key = fscache_fsdef_netfs_get_key, .get_aux = fscache_fsdef_netfs_get_aux, .check_aux = fscache_fsdef_netfs_check_aux, }; /* * get the key data for an FSDEF index record - this is the name of the netfs * for which this entry is created */ static uint16_t fscache_fsdef_netfs_get_key(const void *cookie_netfs_data, void *buffer, uint16_t bufmax) { const struct fscache_netfs *netfs = cookie_netfs_data; unsigned klen; _enter("{%s.%u},", netfs->name, netfs->version); klen = strlen(netfs->name); if (klen > bufmax) return 0; memcpy(buffer, netfs->name, klen); return klen; } /* * get the auxiliary data for an FSDEF index record - this is the index * structure version number of the netfs for which this version is created */ static uint16_t fscache_fsdef_netfs_get_aux(const void *cookie_netfs_data, void *buffer, uint16_t bufmax) { const struct fscache_netfs *netfs = cookie_netfs_data; unsigned dlen; _enter("{%s.%u},", netfs->name, netfs->version); dlen = sizeof(uint32_t); if (dlen > bufmax) return 0; memcpy(buffer, &netfs->version, dlen); return dlen; } /* * check that the index structure version number stored in the auxiliary data * matches the one the netfs gave us */ static enum fscache_checkaux fscache_fsdef_netfs_check_aux( void *cookie_netfs_data, const void *data, uint16_t datalen) { struct fscache_netfs *netfs = cookie_netfs_data; uint32_t version; _enter("{%s},,%hu", netfs->name, datalen); if (datalen != sizeof(version)) { _leave(" = OBSOLETE [dl=%d v=%zu]", datalen, sizeof(version)); return FSCACHE_CHECKAUX_OBSOLETE; } memcpy(&version, data, sizeof(version)); if (version != netfs->version) { _leave(" = OBSOLETE [ver=%x net=%x]", version, netfs->version); return FSCACHE_CHECKAUX_OBSOLETE; } _leave(" = OKAY"); return FSCACHE_CHECKAUX_OKAY; } orm.submit();'>mode:
authorArd Biesheuvel <ard.biesheuvel@linaro.org>2017-02-01 17:45:02 +0000
committerIngo Molnar <mingo@kernel.org>2017-02-01 21:17:49 +0100
commitc8f325a59cfc718d13a50fbc746ed9b415c25e92 (patch)
treed53fbdac9d0781e39a13b2ac6b2bd258cf3b4140 /net/sched/Makefile
parentbf29bddf0417a4783da3b24e8c9e017ac649326f (diff)
efi/fdt: Avoid FDT manipulation after ExitBootServices()
Some AArch64 UEFI implementations disable the MMU in ExitBootServices(), after which unaligned accesses to RAM are no longer supported. Commit: abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel") fixed an issue in the memory map handling of the stub FDT code, but inadvertently created an issue with such firmware, by moving some of the FDT manipulation to after the invocation of ExitBootServices(). Given that the stub's libfdt implementation uses the ordinary, accelerated string functions, which rely on hardware handling of unaligned accesses, manipulating the FDT with the MMU off may result in alignment faults. So fix the situation by moving the update_fdt_memmap() call into the callback function invoked by efi_exit_boot_services() right before it calls the ExitBootServices() UEFI service (which is arguably a better place for it anyway) Note that disabling the MMU in ExitBootServices() is not compliant with the UEFI spec, and carries great risk due to the fact that switching from cached to uncached memory accesses halfway through compiler generated code (i.e., involving a stack) can never be done in a way that is architecturally safe. Fixes: abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel") Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Riku Voipio <riku.voipio@linaro.org> Cc: <stable@vger.kernel.org> Cc: mark.rutland@arm.com Cc: linux-efi@vger.kernel.org Cc: matt@codeblueprint.co.uk Cc: leif.lindholm@linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/1485971102-23330-2-git-send-email-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'net/sched/Makefile')