#include #include #include #include #include "super.h" #include "mds_client.h" /* * Basic fh */ struct ceph_nfs_fh { u64 ino; } __attribute__ ((packed)); /* * Larger fh that includes parent ino. */ struct ceph_nfs_confh { u64 ino, parent_ino; } __attribute__ ((packed)); static int ceph_encode_fh(struct inode *inode, u32 *rawfh, int *max_len, struct inode *parent_inode) { int type; struct ceph_nfs_fh *fh = (void *)rawfh; struct ceph_nfs_confh *cfh = (void *)rawfh; int connected_handle_length = sizeof(*cfh)/4; int handle_length = sizeof(*fh)/4; /* don't re-export snaps */ if (ceph_snap(inode) != CEPH_NOSNAP) return -EINVAL; if (parent_inode && (*max_len < connected_handle_length)) { *max_len = connected_handle_length; return FILEID_INVALID; } else if (*max_len < handle_length) { *max_len = handle_length; return FILEID_INVALID; } if (parent_inode) { dout("encode_fh %llx with parent %llx\n", ceph_ino(inode), ceph_ino(parent_inode)); cfh->ino = ceph_ino(inode); cfh->parent_ino = ceph_ino(parent_inode); *max_len = connected_handle_length; type = FILEID_INO32_GEN_PARENT; } else { dout("encode_fh %llx\n", ceph_ino(inode)); fh->ino = ceph_ino(inode); *max_len = handle_length; type = FILEID_INO32_GEN; } return type; } static struct dentry *__fh_to_dentry(struct super_block *sb, u64 ino) { struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc; struct inode *inode; struct ceph_vino vino; int err; vino.ino = ino; vino.snap = CEPH_NOSNAP; inode = ceph_find_inode(sb, vino); if (!inode) { struct ceph_mds_request *req; int mask; req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPINO, USE_ANY_MDS); if (IS_ERR(req)) return ERR_CAST(req); mask = CEPH_STAT_CAP_INODE; if (ceph_security_xattr_wanted(d_inode(sb->s_root))) mask |= CEPH_CAP_XATTR_SHARED; req->r_args.getattr.mask = cpu_to_le32(mask); req->r_ino1 = vino; req->r_num_caps = 1; err = ceph_mdsc_do_request(mdsc, NULL, req); inode = req->r_target_inode; if (inode) ihold(inode); ceph_mdsc_put_request(req); if (!inode) return ERR_PTR(-ESTALE); } return d_obtain_alias(inode); } /* * convert regular fh to dentry */ static struct dentry *ceph_fh_to_dentry(struct super_block *sb, struct fid *fid, int fh_len, int fh_type) { struct ceph_nfs_fh *fh = (void *)fid->raw; if (fh_type != FILEID_INO32_GEN && fh_type != FILEID_INO32_GEN_PARENT) return NULL; if (fh_len < sizeof(*fh) / 4) return NULL; dout("fh_to_dentry %llx\n", fh->ino); return __fh_to_dentry(sb, fh->ino); } static struct dentry *__get_parent(struct super_block *sb, struct dentry *child, u64 ino) { struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc; struct ceph_mds_request *req; struct inode *inode; int mask; int err; req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPPARENT, USE_ANY_MDS); if (IS_ERR(req)) return ERR_CAST(req); if (child) { req->r_inode = d_inode(child); ihold(d_inode(child)); } else { req->r_ino1 = (struct ceph_vino) { .ino = ino, .snap = CEPH_NOSNAP, }; } mask = CEPH_STAT_CAP_INODE; if (ceph_security_xattr_wanted(d_inode(sb->s_root))) mask |= CEPH_CAP_XATTR_SHARED; req->r_args.getattr.mask = cpu_to_le32(mask); req->r_num_caps = 1; err = ceph_mdsc_do_request(mdsc, NULL, req); inode = req->r_target_inode; if (inode) ihold(inode); ceph_mdsc_put_request(req); if (!inode) return ERR_PTR(-ENOENT); return d_obtain_alias(inode); } static struct dentry *ceph_get_parent(struct dentry *child) { /* don't re-export snaps */ if (ceph_snap(d_inode(child)) != CEPH_NOSNAP) return ERR_PTR(-EINVAL); dout("get_parent %p ino %llx.%llx\n", child, ceph_vinop(d_inode(child))); return __get_parent(child->d_sb, child, 0); } /* * convert regular fh to parent */ static struct dentry *ceph_fh_to_parent(struct super_block *sb, struct fid *fid, int fh_len, int fh_type) { struct ceph_nfs_confh *cfh = (void *)fid->raw; struct dentry *dentry; if (fh_type != FILEID_INO32_GEN_PARENT) return NULL; if (fh_len < sizeof(*cfh) / 4) return NULL; dout("fh_to_parent %llx\n", cfh->parent_ino); dentry = __get_parent(sb, NULL, cfh->ino); if (unlikely(dentry == ERR_PTR(-ENOENT))) dentry = __fh_to_dentry(sb, cfh->parent_ino); return dentry; } static int ceph_get_name(struct dentry *parent, char *name, struct dentry *child) { struct ceph_mds_client *mdsc; struct ceph_mds_request *req; int err; mdsc = ceph_inode_to_client(d_inode(child))->mdsc; req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPNAME, USE_ANY_MDS); if (IS_ERR(req)) return PTR_ERR(req); inode_lock(d_inode(parent)); req->r_inode = d_inode(child); ihold(d_inode(child)); req->r_ino2 = ceph_vino(d_inode(parent)); req->r_locked_dir = d_inode(parent); req->r_num_caps = 2; err = ceph_mdsc_do_request(mdsc, NULL, req); inode_unlock(d_inode(parent)); if (!err) { struct ceph_mds_reply_info_parsed *rinfo = &req->r_reply_info; memcpy(name, rinfo->dname, rinfo->dname_len); name[rinfo->dname_len] = 0; dout("get_name %p ino %llx.%llx name %s\n", child, ceph_vinop(d_inode(child)), name); } else { dout("get_name %p ino %llx.%llx err %d\n", child, ceph_vinop(d_inode(child)), err); } ceph_mdsc_put_request(req); return err; } const struct export_operations ceph_export_ops = { .encode_fh = ceph_encode_fh, .fh_to_dentry = ceph_fh_to_dentry, .fh_to_parent = ceph_fh_to_parent, .get_parent = ceph_get_parent, .get_name = ceph_get_name, }; 2'>kernel/sys_ni.c 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 'kernel/sys_ni.c')