1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071727374757677787980818283848586878889909192939495969798991001011021031041051061071081091101111121131141151161171181191201211221231241251261271281291301311321331341351361371381391401411421431441451461471481491501511521531541551561571581591601611621631641651661671681691701711721731741751761771781791801811821831841851861871881891901911921931941951961971981992002012022032042052062072082092102112122132142152162172182192202212222232242252262272282292302312322332342352362372382392402412422432442452462472482492502512522532542552562572582592602612622632642652662672682692702712722732742752762772782792802812822832842852862872882892902912922932942952962972982993003013023033043053063073083093103113123133143153163173183193203213223233243253263273283293303313323333343353363373383393403413423433443453463473483493503513523533543553563573583593603613623633643653663673683693703713723733743753763773783793803813823833843853863873883893903913923933943953963973983994004014024034044054064074084094104114124134144154164174184194204214224234244254264274284294304314324334344354364374384394404414424434444454464474484494504514524534544554564574584594604614624634644654664674684694704714724734744754764774784794804814824834844854864874884894904914924934944954964974984995005015025035045055065075085095105115125135145155165175185195205215225235245255265275285295305315325335345355365375385395405415425435445455465475485495505515525535545555565575585595605615625635645655665675685695705715725735745755765775785795805815825835845855865875885895905915925935945955965975985996006016026036046056066076086096106116126136146156166176186196206216226236246256266276286296306316326336346356366376386396406416426436446456466476486496506516526536546556566576586596606616626636646656666676686696706716726736746756766776786796806816826836846856866876886896906916926936946956966976986997007017027037047057067077087097107117127137147157167177187197207217227237247257267277287297307317327337347357367377387397407417427437447457467477487497507517527537547557567577587597607617627637647657667677687697707717727737747757767777787797807817827837847857867877887897907917927937947957967977987998008018028038048058068078088098108118128138148158168178188198208218228238248258268278288298308318328338348358368378388398408418428438448458468478488498508518528538548558568578588598608618628638648658668678688698708718728738748758768778788798808818828838848858868878888898908918928938948958968978988999009019029039049059069079089099109119129139149159169179189199209219229239249259269279289299309319329339349359369379389399409419429439449459469479489499509519529539549559569579589599609619629639649659669679689699709719729739749759769779789799809819829839849859869879889899909919929939949959969979989991000100110021003100410051006100710081009101010111012101310141015101610171018101910201021102210231024102510261027102810291030103110321033103410351036103710381039104010411042104310441045104610471048104910501051105210531054105510561057105810591060106110621063106410651066106710681069107010711072107310741075107610771078107910801081108210831084108510861087108810891090109110921093109410951096109710981099110011011102110311041105110611071108110911101111111211131114111511161117111811191120112111221123112411251126112711281129113011311132113311341135113611371138113911401141114211431144114511461147114811491150115111521153115411551156115711581159116011611162116311641165116611671168116911701171117211731174117511761177117811791180118111821183118411851186118711881189119011911192119311941195119611971198119912001201120212031204120512061207120812091210121112121213121412151216121712181219122012211222122312241225122612271228122912301231123212331234123512361237123812391240124112421243124412451246124712481249125012511252125312541255125612571258125912601261126212631264126512661267126812691270127112721273127412751276127712781279128012811282128312841285128612871288128912901291129212931294129512961297129812991300130113021303130413051306130713081309131013111312131313141315131613171318131913201321132213231324132513261327132813291330133113321333133413351336133713381339134013411342134313441345134613471348134913501351135213531354135513561357135813591360136113621363136413651366136713681369137013711372137313741375137613771378137913801381138213831384138513861387138813891390139113921393139413951396139713981399140014011402140314041405140614071408140914101411141214131414141514161417141814191420142114221423142414251426142714281429143014311432143314341435143614371438143914401441144214431444144514461447144814491450145114521453145414551456145714581459146014611462146314641465146614671468146914701471147214731474147514761477147814791480148114821483148414851486148714881489149014911492149314941495149614971498149915001501150215031504150515061507150815091510151115121513151415151516151715181519152015211522152315241525152615271528152915301531153215331534153515361537153815391540154115421543154415451546154715481549155015511552155315541555155615571558155915601561156215631564156515661567156815691570157115721573157415751576157715781579158015811582158315841585158615871588158915901591159215931594159515961597159815991600160116021603160416051606160716081609161016111612161316141615161616171618161916201621162216231624162516261627162816291630163116321633163416351636163716381639164016411642164316441645164616471648164916501651165216531654165516561657165816591660166116621663166416651666166716681669167016711672167316741675167616771678167916801681168216831684168516861687168816891690169116921693169416951696169716981699170017011702170317041705170617071708170917101711171217131714171517161717171817191720172117221723172417251726172717281729173017311732173317341735173617371738173917401741174217431744174517461747174817491750175117521753175417551756175717581759176017611762176317641765176617671768176917701771177217731774177517761777177817791780178117821783178417851786178717881789179017911792179317941795179617971798179918001801180218031804180518061807180818091810181118121813181418151816181718181819182018211822182318241825182618271828182918301831183218331834183518361837183818391840184118421843184418451846184718481849185018511852185318541855185618571858185918601861186218631864186518661867186818691870187118721873187418751876187718781879188018811882188318841885188618871888188918901891189218931894189518961897189818991900190119021903190419051906190719081909191019111912191319141915191619171918191919201921192219231924192519261927192819291930193119321933193419351936193719381939194019411942194319441945194619471948194919501951195219531954195519561957195819591960196119621963196419651966196719681969197019711972197319741975197619771978197919801981198219831984198519861987198819891990199119921993199419951996199719981999200020012002200320042005200620072008200920102011201220132014201520162017201820192020202120222023202420252026202720282029203020312032203320342035203620372038203920402041204220432044204520462047204820492050205120522053205420552056205720582059206020612062206320642065206620672068206920702071207220732074207520762077207820792080208120822083208420852086208720882089209020912092209320942095209620972098209921002101210221032104210521062107210821092110211121122113211421152116211721182119212021212122212321242125212621272128212921302131213221332134213521362137213821392140214121422143214421452146214721482149215021512152215321542155215621572158215921602161216221632164216521662167216821692170217121722173217421752176217721782179218021812182218321842185218621872188218921902191219221932194219521962197219821992200220122022203220422052206220722082209221022112212221322142215221622172218221922202221222222232224222522262227222822292230223122322233223422352236223722382239224022412242224322442245224622472248224922502251225222532254225522562257225822592260226122622263226422652266226722682269227022712272227322742275227622772278227922802281228222832284228522862287228822892290229122922293229422952296229722982299230023012302230323042305230623072308230923102311231223132314231523162317231823192320232123222323232423252326232723282329233023312332233323342335233623372338233923402341234223432344234523462347234823492350235123522353235423552356235723582359236023612362236323642365236623672368236923702371237223732374237523762377237823792380238123822383238423852386238723882389239023912392239323942395239623972398239924002401240224032404240524062407240824092410241124122413241424152416241724182419242024212422242324242425242624272428242924302431243224332434243524362437243824392440244124422443244424452446244724482449245024512452245324542455245624572458245924602461246224632464246524662467246824692470247124722473247424752476247724782479248024812482248324842485248624872488248924902491249224932494249524962497249824992500250125022503250425052506250725082509251025112512251325142515251625172518251925202521252225232524252525262527252825292530253125322533253425352536253725382539254025412542254325442545254625472548254925502551255225532554255525562557255825592560256125622563256425652566256725682569257025712572257325742575257625772578257925802581258225832584258525862587258825892590259125922593259425952596259725982599260026012602260326042605260626072608260926102611261226132614261526162617261826192620262126222623262426252626262726282629263026312632263326342635263626372638263926402641264226432644264526462647264826492650265126522653265426552656265726582659266026612662266326642665266626672668266926702671267226732674267526762677267826792680268126822683268426852686268726882689269026912692269326942695269626972698269927002701270227032704270527062707270827092710271127122713271427152716271727182719272027212722272327242725272627272728272927302731273227332734273527362737273827392740274127422743274427452746274727482749275027512752275327542755275627572758275927602761276227632764276527662767276827692770277127722773277427752776277727782779278027812782278327842785278627872788278927902791279227932794279527962797279827992800280128022803280428052806280728082809281028112812281328142815281628172818281928202821282228232824282528262827282828292830283128322833283428352836283728382839284028412842284328442845284628472848284928502851285228532854285528562857285828592860286128622863286428652866286728682869287028712872287328742875287628772878287928802881288228832884288528862887288828892890289128922893289428952896289728982899290029012902290329042905290629072908290929102911291229132914291529162917291829192920292129222923292429252926292729282929293029312932293329342935293629372938293929402941294229432944294529462947294829492950295129522953295429552956295729582959296029612962296329642965296629672968296929702971297229732974297529762977297829792980298129822983298429852986298729882989299029912992299329942995299629972998299930003001300230033004300530063007300830093010301130123013301430153016301730183019302030213022302330243025 |
- // SPDX-License-Identifier: GPL-2.0-only
- /*
- * VFIO: IOMMU DMA mapping support for Type1 IOMMU
- *
- * Copyright (C) 2012 Red Hat, Inc. All rights reserved.
- * Author: Alex Williamson <alex.williamson@redhat.com>
- *
- * Derived from original vfio:
- * Copyright 2010 Cisco Systems, Inc. All rights reserved.
- * Author: Tom Lyon, pugs@cisco.com
- *
- * We arbitrarily define a Type1 IOMMU as one matching the below code.
- * It could be called the x86 IOMMU as it's designed for AMD-Vi & Intel
- * VT-d, but that makes it harder to re-use as theoretically anyone
- * implementing a similar IOMMU could make use of this. We expect the
- * IOMMU to support the IOMMU API and have few to no restrictions around
- * the IOVA range that can be mapped. The Type1 IOMMU is currently
- * optimized for relatively static mappings of a userspace process with
- * userpsace pages pinned into memory. We also assume devices and IOMMU
- * domains are PCI based as the IOMMU API is still centered around a
- * device/bus interface rather than a group interface.
- */
- #include <linux/compat.h>
- #include <linux/device.h>
- #include <linux/fs.h>
- #include <linux/highmem.h>
- #include <linux/iommu.h>
- #include <linux/module.h>
- #include <linux/mm.h>
- #include <linux/kthread.h>
- #include <linux/rbtree.h>
- #include <linux/sched/signal.h>
- #include <linux/sched/mm.h>
- #include <linux/slab.h>
- #include <linux/uaccess.h>
- #include <linux/vfio.h>
- #include <linux/workqueue.h>
- #include <linux/mdev.h>
- #include <linux/notifier.h>
- #include <linux/dma-iommu.h>
- #include <linux/irqdomain.h>
- #define DRIVER_VERSION "0.2"
- #define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>"
- #define DRIVER_DESC "Type1 IOMMU driver for VFIO"
- static bool allow_unsafe_interrupts;
- module_param_named(allow_unsafe_interrupts,
- allow_unsafe_interrupts, bool, S_IRUGO | S_IWUSR);
- MODULE_PARM_DESC(allow_unsafe_interrupts,
- "Enable VFIO IOMMU support for on platforms without interrupt remapping support.");
- static bool disable_hugepages;
- module_param_named(disable_hugepages,
- disable_hugepages, bool, S_IRUGO | S_IWUSR);
- MODULE_PARM_DESC(disable_hugepages,
- "Disable VFIO IOMMU support for IOMMU hugepages.");
- static unsigned int dma_entry_limit __read_mostly = U16_MAX;
- module_param_named(dma_entry_limit, dma_entry_limit, uint, 0644);
- MODULE_PARM_DESC(dma_entry_limit,
- "Maximum number of user DMA mappings per container (65535).");
- struct vfio_iommu {
- struct list_head domain_list;
- struct list_head iova_list;
- struct vfio_domain *external_domain; /* domain for external user */
- struct mutex lock;
- struct rb_root dma_list;
- struct blocking_notifier_head notifier;
- unsigned int dma_avail;
- uint64_t pgsize_bitmap;
- bool v2;
- bool nesting;
- bool dirty_page_tracking;
- bool pinned_page_dirty_scope;
- };
- struct vfio_domain {
- struct iommu_domain *domain;
- struct list_head next;
- struct list_head group_list;
- int prot; /* IOMMU_CACHE */
- bool fgsp; /* Fine-grained super pages */
- };
- struct vfio_dma {
- struct rb_node node;
- dma_addr_t iova; /* Device address */
- unsigned long vaddr; /* Process virtual addr */
- size_t size; /* Map size (bytes) */
- int prot; /* IOMMU_READ/WRITE */
- bool iommu_mapped;
- bool lock_cap; /* capable(CAP_IPC_LOCK) */
- struct task_struct *task;
- struct rb_root pfn_list; /* Ex-user pinned pfn list */
- unsigned long *bitmap;
- };
- struct vfio_group {
- struct iommu_group *iommu_group;
- struct list_head next;
- bool mdev_group; /* An mdev group */
- bool pinned_page_dirty_scope;
- };
- struct vfio_iova {
- struct list_head list;
- dma_addr_t start;
- dma_addr_t end;
- };
- /*
- * Guest RAM pinning working set or DMA target
- */
- struct vfio_pfn {
- struct rb_node node;
- dma_addr_t iova; /* Device address */
- unsigned long pfn; /* Host pfn */
- unsigned int ref_count;
- };
- struct vfio_regions {
- struct list_head list;
- dma_addr_t iova;
- phys_addr_t phys;
- size_t len;
- };
- #define IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu) \
- (!list_empty(&iommu->domain_list))
- #define DIRTY_BITMAP_BYTES(n) (ALIGN(n, BITS_PER_TYPE(u64)) / BITS_PER_BYTE)
- /*
- * Input argument of number of bits to bitmap_set() is unsigned integer, which
- * further casts to signed integer for unaligned multi-bit operation,
- * __bitmap_set().
- * Then maximum bitmap size supported is 2^31 bits divided by 2^3 bits/byte,
- * that is 2^28 (256 MB) which maps to 2^31 * 2^12 = 2^43 (8TB) on 4K page
- * system.
- */
- #define DIRTY_BITMAP_PAGES_MAX ((u64)INT_MAX)
- #define DIRTY_BITMAP_SIZE_MAX DIRTY_BITMAP_BYTES(DIRTY_BITMAP_PAGES_MAX)
- static int put_pfn(unsigned long pfn, int prot);
- static struct vfio_group *vfio_iommu_find_iommu_group(struct vfio_iommu *iommu,
- struct iommu_group *iommu_group);
- static void update_pinned_page_dirty_scope(struct vfio_iommu *iommu);
- /*
- * This code handles mapping and unmapping of user data buffers
- * into DMA'ble space using the IOMMU
- */
- static struct vfio_dma *vfio_find_dma(struct vfio_iommu *iommu,
- dma_addr_t start, size_t size)
- {
- struct rb_node *node = iommu->dma_list.rb_node;
- while (node) {
- struct vfio_dma *dma = rb_entry(node, struct vfio_dma, node);
- if (start + size <= dma->iova)
- node = node->rb_left;
- else if (start >= dma->iova + dma->size)
- node = node->rb_right;
- else
- return dma;
- }
- return NULL;
- }
- static void vfio_link_dma(struct vfio_iommu *iommu, struct vfio_dma *new)
- {
- struct rb_node **link = &iommu->dma_list.rb_node, *parent = NULL;
- struct vfio_dma *dma;
- while (*link) {
- parent = *link;
- dma = rb_entry(parent, struct vfio_dma, node);
- if (new->iova + new->size <= dma->iova)
- link = &(*link)->rb_left;
- else
- link = &(*link)->rb_right;
- }
- rb_link_node(&new->node, parent, link);
- rb_insert_color(&new->node, &iommu->dma_list);
- }
- static void vfio_unlink_dma(struct vfio_iommu *iommu, struct vfio_dma *old)
- {
- rb_erase(&old->node, &iommu->dma_list);
- }
- static int vfio_dma_bitmap_alloc(struct vfio_dma *dma, size_t pgsize)
- {
- uint64_t npages = dma->size / pgsize;
- if (npages > DIRTY_BITMAP_PAGES_MAX)
- return -EINVAL;
- /*
- * Allocate extra 64 bits that are used to calculate shift required for
- * bitmap_shift_left() to manipulate and club unaligned number of pages
- * in adjacent vfio_dma ranges.
- */
- dma->bitmap = kvzalloc(DIRTY_BITMAP_BYTES(npages) + sizeof(u64),
- GFP_KERNEL);
- if (!dma->bitmap)
- return -ENOMEM;
- return 0;
- }
- static void vfio_dma_bitmap_free(struct vfio_dma *dma)
- {
- kfree(dma->bitmap);
- dma->bitmap = NULL;
- }
- static void vfio_dma_populate_bitmap(struct vfio_dma *dma, size_t pgsize)
- {
- struct rb_node *p;
- unsigned long pgshift = __ffs(pgsize);
- for (p = rb_first(&dma->pfn_list); p; p = rb_next(p)) {
- struct vfio_pfn *vpfn = rb_entry(p, struct vfio_pfn, node);
- bitmap_set(dma->bitmap, (vpfn->iova - dma->iova) >> pgshift, 1);
- }
- }
- static void vfio_iommu_populate_bitmap_full(struct vfio_iommu *iommu)
- {
- struct rb_node *n;
- unsigned long pgshift = __ffs(iommu->pgsize_bitmap);
- for (n = rb_first(&iommu->dma_list); n; n = rb_next(n)) {
- struct vfio_dma *dma = rb_entry(n, struct vfio_dma, node);
- bitmap_set(dma->bitmap, 0, dma->size >> pgshift);
- }
- }
- static int vfio_dma_bitmap_alloc_all(struct vfio_iommu *iommu, size_t pgsize)
- {
- struct rb_node *n;
- for (n = rb_first(&iommu->dma_list); n; n = rb_next(n)) {
- struct vfio_dma *dma = rb_entry(n, struct vfio_dma, node);
- int ret;
- ret = vfio_dma_bitmap_alloc(dma, pgsize);
- if (ret) {
- struct rb_node *p;
- for (p = rb_prev(n); p; p = rb_prev(p)) {
- struct vfio_dma *dma = rb_entry(n,
- struct vfio_dma, node);
- vfio_dma_bitmap_free(dma);
- }
- return ret;
- }
- vfio_dma_populate_bitmap(dma, pgsize);
- }
- return 0;
- }
- static void vfio_dma_bitmap_free_all(struct vfio_iommu *iommu)
- {
- struct rb_node *n;
- for (n = rb_first(&iommu->dma_list); n; n = rb_next(n)) {
- struct vfio_dma *dma = rb_entry(n, struct vfio_dma, node);
- vfio_dma_bitmap_free(dma);
- }
- }
- /*
- * Helper Functions for host iova-pfn list
- */
- static struct vfio_pfn *vfio_find_vpfn(struct vfio_dma *dma, dma_addr_t iova)
- {
- struct vfio_pfn *vpfn;
- struct rb_node *node = dma->pfn_list.rb_node;
- while (node) {
- vpfn = rb_entry(node, struct vfio_pfn, node);
- if (iova < vpfn->iova)
- node = node->rb_left;
- else if (iova > vpfn->iova)
- node = node->rb_right;
- else
- return vpfn;
- }
- return NULL;
- }
- static void vfio_link_pfn(struct vfio_dma *dma,
- struct vfio_pfn *new)
- {
- struct rb_node **link, *parent = NULL;
- struct vfio_pfn *vpfn;
- link = &dma->pfn_list.rb_node;
- while (*link) {
- parent = *link;
- vpfn = rb_entry(parent, struct vfio_pfn, node);
- if (new->iova < vpfn->iova)
- link = &(*link)->rb_left;
- else
- link = &(*link)->rb_right;
- }
- rb_link_node(&new->node, parent, link);
- rb_insert_color(&new->node, &dma->pfn_list);
- }
- static void vfio_unlink_pfn(struct vfio_dma *dma, struct vfio_pfn *old)
- {
- rb_erase(&old->node, &dma->pfn_list);
- }
- static int vfio_add_to_pfn_list(struct vfio_dma *dma, dma_addr_t iova,
- unsigned long pfn)
- {
- struct vfio_pfn *vpfn;
- vpfn = kzalloc(sizeof(*vpfn), GFP_KERNEL);
- if (!vpfn)
- return -ENOMEM;
- vpfn->iova = iova;
- vpfn->pfn = pfn;
- vpfn->ref_count = 1;
- vfio_link_pfn(dma, vpfn);
- return 0;
- }
- static void vfio_remove_from_pfn_list(struct vfio_dma *dma,
- struct vfio_pfn *vpfn)
- {
- vfio_unlink_pfn(dma, vpfn);
- kfree(vpfn);
- }
- static struct vfio_pfn *vfio_iova_get_vfio_pfn(struct vfio_dma *dma,
- unsigned long iova)
- {
- struct vfio_pfn *vpfn = vfio_find_vpfn(dma, iova);
- if (vpfn)
- vpfn->ref_count++;
- return vpfn;
- }
- static int vfio_iova_put_vfio_pfn(struct vfio_dma *dma, struct vfio_pfn *vpfn)
- {
- int ret = 0;
- vpfn->ref_count--;
- if (!vpfn->ref_count) {
- ret = put_pfn(vpfn->pfn, dma->prot);
- vfio_remove_from_pfn_list(dma, vpfn);
- }
- return ret;
- }
- static int vfio_lock_acct(struct vfio_dma *dma, long npage, bool async)
- {
- struct mm_struct *mm;
- int ret;
- if (!npage)
- return 0;
- mm = async ? get_task_mm(dma->task) : dma->task->mm;
- if (!mm)
- return -ESRCH; /* process exited */
- ret = mmap_write_lock_killable(mm);
- if (!ret) {
- ret = __account_locked_vm(mm, abs(npage), npage > 0, dma->task,
- dma->lock_cap);
- mmap_write_unlock(mm);
- }
- if (async)
- mmput(mm);
- return ret;
- }
- /*
- * Some mappings aren't backed by a struct page, for example an mmap'd
- * MMIO range for our own or another device. These use a different
- * pfn conversion and shouldn't be tracked as locked pages.
- * For compound pages, any driver that sets the reserved bit in head
- * page needs to set the reserved bit in all subpages to be safe.
- */
- static bool is_invalid_reserved_pfn(unsigned long pfn)
- {
- if (pfn_valid(pfn))
- return PageReserved(pfn_to_page(pfn));
- return true;
- }
- static int put_pfn(unsigned long pfn, int prot)
- {
- if (!is_invalid_reserved_pfn(pfn)) {
- struct page *page = pfn_to_page(pfn);
- unpin_user_pages_dirty_lock(&page, 1, prot & IOMMU_WRITE);
- return 1;
- }
- return 0;
- }
- static int follow_fault_pfn(struct vm_area_struct *vma, struct mm_struct *mm,
- unsigned long vaddr, unsigned long *pfn,
- bool write_fault)
- {
- pte_t *ptep;
- spinlock_t *ptl;
- int ret;
- ret = follow_pte(vma->vm_mm, vaddr, &ptep, &ptl);
- if (ret) {
- bool unlocked = false;
- ret = fixup_user_fault(mm, vaddr,
- FAULT_FLAG_REMOTE |
- (write_fault ? FAULT_FLAG_WRITE : 0),
- &unlocked);
- if (unlocked)
- return -EAGAIN;
- if (ret)
- return ret;
- ret = follow_pte(vma->vm_mm, vaddr, &ptep, &ptl);
- if (ret)
- return ret;
- }
- if (write_fault && !pte_write(*ptep))
- ret = -EFAULT;
- else
- *pfn = pte_pfn(*ptep);
- pte_unmap_unlock(ptep, ptl);
- return ret;
- }
- static int vaddr_get_pfn(struct mm_struct *mm, unsigned long vaddr,
- int prot, unsigned long *pfn)
- {
- struct page *page[1];
- struct vm_area_struct *vma;
- unsigned int flags = 0;
- int ret;
- if (prot & IOMMU_WRITE)
- flags |= FOLL_WRITE;
- mmap_read_lock(mm);
- ret = pin_user_pages_remote(mm, vaddr, 1, flags | FOLL_LONGTERM,
- page, NULL, NULL);
- if (ret == 1) {
- *pfn = page_to_pfn(page[0]);
- ret = 0;
- goto done;
- }
- vaddr = untagged_addr(vaddr);
- retry:
- vma = find_vma_intersection(mm, vaddr, vaddr + 1);
- if (vma && vma->vm_flags & VM_PFNMAP) {
- ret = follow_fault_pfn(vma, mm, vaddr, pfn, prot & IOMMU_WRITE);
- if (ret == -EAGAIN)
- goto retry;
- if (!ret && !is_invalid_reserved_pfn(*pfn))
- ret = -EFAULT;
- }
- done:
- mmap_read_unlock(mm);
- return ret;
- }
- /*
- * Attempt to pin pages. We really don't want to track all the pfns and
- * the iommu can only map chunks of consecutive pfns anyway, so get the
- * first page and all consecutive pages with the same locking.
- */
- static long vfio_pin_pages_remote(struct vfio_dma *dma, unsigned long vaddr,
- long npage, unsigned long *pfn_base,
- unsigned long limit)
- {
- unsigned long pfn = 0;
- long ret, pinned = 0, lock_acct = 0;
- bool rsvd;
- dma_addr_t iova = vaddr - dma->vaddr + dma->iova;
- /* This code path is only user initiated */
- if (!current->mm)
- return -ENODEV;
- ret = vaddr_get_pfn(current->mm, vaddr, dma->prot, pfn_base);
- if (ret)
- return ret;
- pinned++;
- rsvd = is_invalid_reserved_pfn(*pfn_base);
- /*
- * Reserved pages aren't counted against the user, externally pinned
- * pages are already counted against the user.
- */
- if (!rsvd && !vfio_find_vpfn(dma, iova)) {
- if (!dma->lock_cap && current->mm->locked_vm + 1 > limit) {
- put_pfn(*pfn_base, dma->prot);
- pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n", __func__,
- limit << PAGE_SHIFT);
- return -ENOMEM;
- }
- lock_acct++;
- }
- if (unlikely(disable_hugepages))
- goto out;
- /* Lock all the consecutive pages from pfn_base */
- for (vaddr += PAGE_SIZE, iova += PAGE_SIZE; pinned < npage;
- pinned++, vaddr += PAGE_SIZE, iova += PAGE_SIZE) {
- ret = vaddr_get_pfn(current->mm, vaddr, dma->prot, &pfn);
- if (ret)
- break;
- if (pfn != *pfn_base + pinned ||
- rsvd != is_invalid_reserved_pfn(pfn)) {
- put_pfn(pfn, dma->prot);
- break;
- }
- if (!rsvd && !vfio_find_vpfn(dma, iova)) {
- if (!dma->lock_cap &&
- current->mm->locked_vm + lock_acct + 1 > limit) {
- put_pfn(pfn, dma->prot);
- pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n",
- __func__, limit << PAGE_SHIFT);
- ret = -ENOMEM;
- goto unpin_out;
- }
- lock_acct++;
- }
- }
- out:
- ret = vfio_lock_acct(dma, lock_acct, false);
- unpin_out:
- if (ret) {
- if (!rsvd) {
- for (pfn = *pfn_base ; pinned ; pfn++, pinned--)
- put_pfn(pfn, dma->prot);
- }
- return ret;
- }
- return pinned;
- }
- static long vfio_unpin_pages_remote(struct vfio_dma *dma, dma_addr_t iova,
- unsigned long pfn, long npage,
- bool do_accounting)
- {
- long unlocked = 0, locked = 0;
- long i;
- for (i = 0; i < npage; i++, iova += PAGE_SIZE) {
- if (put_pfn(pfn++, dma->prot)) {
- unlocked++;
- if (vfio_find_vpfn(dma, iova))
- locked++;
- }
- }
- if (do_accounting)
- vfio_lock_acct(dma, locked - unlocked, true);
- return unlocked;
- }
- static int vfio_pin_page_external(struct vfio_dma *dma, unsigned long vaddr,
- unsigned long *pfn_base, bool do_accounting)
- {
- struct mm_struct *mm;
- int ret;
- mm = get_task_mm(dma->task);
- if (!mm)
- return -ENODEV;
- ret = vaddr_get_pfn(mm, vaddr, dma->prot, pfn_base);
- if (!ret && do_accounting && !is_invalid_reserved_pfn(*pfn_base)) {
- ret = vfio_lock_acct(dma, 1, true);
- if (ret) {
- put_pfn(*pfn_base, dma->prot);
- if (ret == -ENOMEM)
- pr_warn("%s: Task %s (%d) RLIMIT_MEMLOCK "
- "(%ld) exceeded\n", __func__,
- dma->task->comm, task_pid_nr(dma->task),
- task_rlimit(dma->task, RLIMIT_MEMLOCK));
- }
- }
- mmput(mm);
- return ret;
- }
- static int vfio_unpin_page_external(struct vfio_dma *dma, dma_addr_t iova,
- bool do_accounting)
- {
- int unlocked;
- struct vfio_pfn *vpfn = vfio_find_vpfn(dma, iova);
- if (!vpfn)
- return 0;
- unlocked = vfio_iova_put_vfio_pfn(dma, vpfn);
- if (do_accounting)
- vfio_lock_acct(dma, -unlocked, true);
- return unlocked;
- }
- static int vfio_iommu_type1_pin_pages(void *iommu_data,
- struct iommu_group *iommu_group,
- unsigned long *user_pfn,
- int npage, int prot,
- unsigned long *phys_pfn)
- {
- struct vfio_iommu *iommu = iommu_data;
- struct vfio_group *group;
- int i, j, ret;
- unsigned long remote_vaddr;
- struct vfio_dma *dma;
- bool do_accounting;
- if (!iommu || !user_pfn || !phys_pfn)
- return -EINVAL;
- /* Supported for v2 version only */
- if (!iommu->v2)
- return -EACCES;
- mutex_lock(&iommu->lock);
- /* Fail if notifier list is empty */
- if (!iommu->notifier.head) {
- ret = -EINVAL;
- goto pin_done;
- }
- /*
- * If iommu capable domain exist in the container then all pages are
- * already pinned and accounted. Accouting should be done if there is no
- * iommu capable domain in the container.
- */
- do_accounting = !IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu);
- for (i = 0; i < npage; i++) {
- dma_addr_t iova;
- struct vfio_pfn *vpfn;
- iova = user_pfn[i] << PAGE_SHIFT;
- dma = vfio_find_dma(iommu, iova, PAGE_SIZE);
- if (!dma) {
- ret = -EINVAL;
- goto pin_unwind;
- }
- if ((dma->prot & prot) != prot) {
- ret = -EPERM;
- goto pin_unwind;
- }
- vpfn = vfio_iova_get_vfio_pfn(dma, iova);
- if (vpfn) {
- phys_pfn[i] = vpfn->pfn;
- continue;
- }
- remote_vaddr = dma->vaddr + (iova - dma->iova);
- ret = vfio_pin_page_external(dma, remote_vaddr, &phys_pfn[i],
- do_accounting);
- if (ret)
- goto pin_unwind;
- ret = vfio_add_to_pfn_list(dma, iova, phys_pfn[i]);
- if (ret) {
- if (put_pfn(phys_pfn[i], dma->prot) && do_accounting)
- vfio_lock_acct(dma, -1, true);
- goto pin_unwind;
- }
- if (iommu->dirty_page_tracking) {
- unsigned long pgshift = __ffs(iommu->pgsize_bitmap);
- /*
- * Bitmap populated with the smallest supported page
- * size
- */
- bitmap_set(dma->bitmap,
- (iova - dma->iova) >> pgshift, 1);
- }
- }
- ret = i;
- group = vfio_iommu_find_iommu_group(iommu, iommu_group);
- if (!group->pinned_page_dirty_scope) {
- group->pinned_page_dirty_scope = true;
- update_pinned_page_dirty_scope(iommu);
- }
- goto pin_done;
- pin_unwind:
- phys_pfn[i] = 0;
- for (j = 0; j < i; j++) {
- dma_addr_t iova;
- iova = user_pfn[j] << PAGE_SHIFT;
- dma = vfio_find_dma(iommu, iova, PAGE_SIZE);
- vfio_unpin_page_external(dma, iova, do_accounting);
- phys_pfn[j] = 0;
- }
- pin_done:
- mutex_unlock(&iommu->lock);
- return ret;
- }
- static int vfio_iommu_type1_unpin_pages(void *iommu_data,
- unsigned long *user_pfn,
- int npage)
- {
- struct vfio_iommu *iommu = iommu_data;
- bool do_accounting;
- int i;
- if (!iommu || !user_pfn)
- return -EINVAL;
- /* Supported for v2 version only */
- if (!iommu->v2)
- return -EACCES;
- mutex_lock(&iommu->lock);
- do_accounting = !IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu);
- for (i = 0; i < npage; i++) {
- struct vfio_dma *dma;
- dma_addr_t iova;
- iova = user_pfn[i] << PAGE_SHIFT;
- dma = vfio_find_dma(iommu, iova, PAGE_SIZE);
- if (!dma)
- goto unpin_exit;
- vfio_unpin_page_external(dma, iova, do_accounting);
- }
- unpin_exit:
- mutex_unlock(&iommu->lock);
- return i > npage ? npage : (i > 0 ? i : -EINVAL);
- }
- static long vfio_sync_unpin(struct vfio_dma *dma, struct vfio_domain *domain,
- struct list_head *regions,
- struct iommu_iotlb_gather *iotlb_gather)
- {
- long unlocked = 0;
- struct vfio_regions *entry, *next;
- iommu_iotlb_sync(domain->domain, iotlb_gather);
- list_for_each_entry_safe(entry, next, regions, list) {
- unlocked += vfio_unpin_pages_remote(dma,
- entry->iova,
- entry->phys >> PAGE_SHIFT,
- entry->len >> PAGE_SHIFT,
- false);
- list_del(&entry->list);
- kfree(entry);
- }
- cond_resched();
- return unlocked;
- }
- /*
- * Generally, VFIO needs to unpin remote pages after each IOTLB flush.
- * Therefore, when using IOTLB flush sync interface, VFIO need to keep track
- * of these regions (currently using a list).
- *
- * This value specifies maximum number of regions for each IOTLB flush sync.
- */
- #define VFIO_IOMMU_TLB_SYNC_MAX 512
- static size_t unmap_unpin_fast(struct vfio_domain *domain,
- struct vfio_dma *dma, dma_addr_t *iova,
- size_t len, phys_addr_t phys, long *unlocked,
- struct list_head *unmapped_list,
- int *unmapped_cnt,
- struct iommu_iotlb_gather *iotlb_gather)
- {
- size_t unmapped = 0;
- struct vfio_regions *entry = kzalloc(sizeof(*entry), GFP_KERNEL);
- if (entry) {
- unmapped = iommu_unmap_fast(domain->domain, *iova, len,
- iotlb_gather);
- if (!unmapped) {
- kfree(entry);
- } else {
- entry->iova = *iova;
- entry->phys = phys;
- entry->len = unmapped;
- list_add_tail(&entry->list, unmapped_list);
- *iova += unmapped;
- (*unmapped_cnt)++;
- }
- }
- /*
- * Sync if the number of fast-unmap regions hits the limit
- * or in case of errors.
- */
- if (*unmapped_cnt >= VFIO_IOMMU_TLB_SYNC_MAX || !unmapped) {
- *unlocked += vfio_sync_unpin(dma, domain, unmapped_list,
- iotlb_gather);
- *unmapped_cnt = 0;
- }
- return unmapped;
- }
- static size_t unmap_unpin_slow(struct vfio_domain *domain,
- struct vfio_dma *dma, dma_addr_t *iova,
- size_t len, phys_addr_t phys,
- long *unlocked)
- {
- size_t unmapped = iommu_unmap(domain->domain, *iova, len);
- if (unmapped) {
- *unlocked += vfio_unpin_pages_remote(dma, *iova,
- phys >> PAGE_SHIFT,
- unmapped >> PAGE_SHIFT,
- false);
- *iova += unmapped;
- cond_resched();
- }
- return unmapped;
- }
- static long vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma,
- bool do_accounting)
- {
- dma_addr_t iova = dma->iova, end = dma->iova + dma->size;
- struct vfio_domain *domain, *d;
- LIST_HEAD(unmapped_region_list);
- struct iommu_iotlb_gather iotlb_gather;
- int unmapped_region_cnt = 0;
- long unlocked = 0;
- if (!dma->size)
- return 0;
- if (!IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu))
- return 0;
- /*
- * We use the IOMMU to track the physical addresses, otherwise we'd
- * need a much more complicated tracking system. Unfortunately that
- * means we need to use one of the iommu domains to figure out the
- * pfns to unpin. The rest need to be unmapped in advance so we have
- * no iommu translations remaining when the pages are unpinned.
- */
- domain = d = list_first_entry(&iommu->domain_list,
- struct vfio_domain, next);
- list_for_each_entry_continue(d, &iommu->domain_list, next) {
- iommu_unmap(d->domain, dma->iova, dma->size);
- cond_resched();
- }
- iommu_iotlb_gather_init(&iotlb_gather);
- while (iova < end) {
- size_t unmapped, len;
- phys_addr_t phys, next;
- phys = iommu_iova_to_phys(domain->domain, iova);
- if (WARN_ON(!phys)) {
- iova += PAGE_SIZE;
- continue;
- }
- /*
- * To optimize for fewer iommu_unmap() calls, each of which
- * may require hardware cache flushing, try to find the
- * largest contiguous physical memory chunk to unmap.
- */
- for (len = PAGE_SIZE;
- !domain->fgsp && iova + len < end; len += PAGE_SIZE) {
- next = iommu_iova_to_phys(domain->domain, iova + len);
- if (next != phys + len)
- break;
- }
- /*
- * First, try to use fast unmap/unpin. In case of failure,
- * switch to slow unmap/unpin path.
- */
- unmapped = unmap_unpin_fast(domain, dma, &iova, len, phys,
- &unlocked, &unmapped_region_list,
- &unmapped_region_cnt,
- &iotlb_gather);
- if (!unmapped) {
- unmapped = unmap_unpin_slow(domain, dma, &iova, len,
- phys, &unlocked);
- if (WARN_ON(!unmapped))
- break;
- }
- }
- dma->iommu_mapped = false;
- if (unmapped_region_cnt) {
- unlocked += vfio_sync_unpin(dma, domain, &unmapped_region_list,
- &iotlb_gather);
- }
- if (do_accounting) {
- vfio_lock_acct(dma, -unlocked, true);
- return 0;
- }
- return unlocked;
- }
- static void vfio_remove_dma(struct vfio_iommu *iommu, struct vfio_dma *dma)
- {
- WARN_ON(!RB_EMPTY_ROOT(&dma->pfn_list));
- vfio_unmap_unpin(iommu, dma, true);
- vfio_unlink_dma(iommu, dma);
- put_task_struct(dma->task);
- vfio_dma_bitmap_free(dma);
- kfree(dma);
- iommu->dma_avail++;
- }
- static void vfio_update_pgsize_bitmap(struct vfio_iommu *iommu)
- {
- struct vfio_domain *domain;
- iommu->pgsize_bitmap = ULONG_MAX;
- list_for_each_entry(domain, &iommu->domain_list, next)
- iommu->pgsize_bitmap &= domain->domain->pgsize_bitmap;
- /*
- * In case the IOMMU supports page sizes smaller than PAGE_SIZE
- * we pretend PAGE_SIZE is supported and hide sub-PAGE_SIZE sizes.
- * That way the user will be able to map/unmap buffers whose size/
- * start address is aligned with PAGE_SIZE. Pinning code uses that
- * granularity while iommu driver can use the sub-PAGE_SIZE size
- * to map the buffer.
- */
- if (iommu->pgsize_bitmap & ~PAGE_MASK) {
- iommu->pgsize_bitmap &= PAGE_MASK;
- iommu->pgsize_bitmap |= PAGE_SIZE;
- }
- }
- static int update_user_bitmap(u64 __user *bitmap, struct vfio_iommu *iommu,
- struct vfio_dma *dma, dma_addr_t base_iova,
- size_t pgsize)
- {
- unsigned long pgshift = __ffs(pgsize);
- unsigned long nbits = dma->size >> pgshift;
- unsigned long bit_offset = (dma->iova - base_iova) >> pgshift;
- unsigned long copy_offset = bit_offset / BITS_PER_LONG;
- unsigned long shift = bit_offset % BITS_PER_LONG;
- unsigned long leftover;
- /*
- * mark all pages dirty if any IOMMU capable device is not able
- * to report dirty pages and all pages are pinned and mapped.
- */
- if (!iommu->pinned_page_dirty_scope && dma->iommu_mapped)
- bitmap_set(dma->bitmap, 0, nbits);
- if (shift) {
- bitmap_shift_left(dma->bitmap, dma->bitmap, shift,
- nbits + shift);
- if (copy_from_user(&leftover,
- (void __user *)(bitmap + copy_offset),
- sizeof(leftover)))
- return -EFAULT;
- bitmap_or(dma->bitmap, dma->bitmap, &leftover, shift);
- }
- if (copy_to_user((void __user *)(bitmap + copy_offset), dma->bitmap,
- DIRTY_BITMAP_BYTES(nbits + shift)))
- return -EFAULT;
- return 0;
- }
- static int vfio_iova_dirty_bitmap(u64 __user *bitmap, struct vfio_iommu *iommu,
- dma_addr_t iova, size_t size, size_t pgsize)
- {
- struct vfio_dma *dma;
- struct rb_node *n;
- unsigned long pgshift = __ffs(pgsize);
- int ret;
- /*
- * GET_BITMAP request must fully cover vfio_dma mappings. Multiple
- * vfio_dma mappings may be clubbed by specifying large ranges, but
- * there must not be any previous mappings bisected by the range.
- * An error will be returned if these conditions are not met.
- */
- dma = vfio_find_dma(iommu, iova, 1);
- if (dma && dma->iova != iova)
- return -EINVAL;
- dma = vfio_find_dma(iommu, iova + size - 1, 0);
- if (dma && dma->iova + dma->size != iova + size)
- return -EINVAL;
- for (n = rb_first(&iommu->dma_list); n; n = rb_next(n)) {
- struct vfio_dma *dma = rb_entry(n, struct vfio_dma, node);
- if (dma->iova < iova)
- continue;
- if (dma->iova > iova + size - 1)
- break;
- ret = update_user_bitmap(bitmap, iommu, dma, iova, pgsize);
- if (ret)
- return ret;
- /*
- * Re-populate bitmap to include all pinned pages which are
- * considered as dirty but exclude pages which are unpinned and
- * pages which are marked dirty by vfio_dma_rw()
- */
- bitmap_clear(dma->bitmap, 0, dma->size >> pgshift);
- vfio_dma_populate_bitmap(dma, pgsize);
- }
- return 0;
- }
- static int verify_bitmap_size(uint64_t npages, uint64_t bitmap_size)
- {
- if (!npages || !bitmap_size || (bitmap_size > DIRTY_BITMAP_SIZE_MAX) ||
- (bitmap_size < DIRTY_BITMAP_BYTES(npages)))
- return -EINVAL;
- return 0;
- }
- static int vfio_dma_do_unmap(struct vfio_iommu *iommu,
- struct vfio_iommu_type1_dma_unmap *unmap,
- struct vfio_bitmap *bitmap)
- {
- struct vfio_dma *dma, *dma_last = NULL;
- size_t unmapped = 0, pgsize;
- int ret = 0, retries = 0;
- unsigned long pgshift;
- mutex_lock(&iommu->lock);
- pgshift = __ffs(iommu->pgsize_bitmap);
- pgsize = (size_t)1 << pgshift;
- if (unmap->iova & (pgsize - 1)) {
- ret = -EINVAL;
- goto unlock;
- }
- if (!unmap->size || unmap->size & (pgsize - 1)) {
- ret = -EINVAL;
- goto unlock;
- }
- if (unmap->iova + unmap->size - 1 < unmap->iova ||
- unmap->size > SIZE_MAX) {
- ret = -EINVAL;
- goto unlock;
- }
- /* When dirty tracking is enabled, allow only min supported pgsize */
- if ((unmap->flags & VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP) &&
- (!iommu->dirty_page_tracking || (bitmap->pgsize != pgsize))) {
- ret = -EINVAL;
- goto unlock;
- }
- WARN_ON((pgsize - 1) & PAGE_MASK);
- again:
- /*
- * vfio-iommu-type1 (v1) - User mappings were coalesced together to
- * avoid tracking individual mappings. This means that the granularity
- * of the original mapping was lost and the user was allowed to attempt
- * to unmap any range. Depending on the contiguousness of physical
- * memory and page sizes supported by the IOMMU, arbitrary unmaps may
- * or may not have worked. We only guaranteed unmap granularity
- * matching the original mapping; even though it was untracked here,
- * the original mappings are reflected in IOMMU mappings. This
- * resulted in a couple unusual behaviors. First, if a range is not
- * able to be unmapped, ex. a set of 4k pages that was mapped as a
- * 2M hugepage into the IOMMU, the unmap ioctl returns success but with
- * a zero sized unmap. Also, if an unmap request overlaps the first
- * address of a hugepage, the IOMMU will unmap the entire hugepage.
- * This also returns success and the returned unmap size reflects the
- * actual size unmapped.
- *
- * We attempt to maintain compatibility with this "v1" interface, but
- * we take control out of the hands of the IOMMU. Therefore, an unmap
- * request offset from the beginning of the original mapping will
- * return success with zero sized unmap. And an unmap request covering
- * the first iova of mapping will unmap the entire range.
- *
- * The v2 version of this interface intends to be more deterministic.
- * Unmap requests must fully cover previous mappings. Multiple
- * mappings may still be unmaped by specifying large ranges, but there
- * must not be any previous mappings bisected by the range. An error
- * will be returned if these conditions are not met. The v2 interface
- * will only return success and a size of zero if there were no
- * mappings within the range.
- */
- if (iommu->v2) {
- dma = vfio_find_dma(iommu, unmap->iova, 1);
- if (dma && dma->iova != unmap->iova) {
- ret = -EINVAL;
- goto unlock;
- }
- dma = vfio_find_dma(iommu, unmap->iova + unmap->size - 1, 0);
- if (dma && dma->iova + dma->size != unmap->iova + unmap->size) {
- ret = -EINVAL;
- goto unlock;
- }
- }
- while ((dma = vfio_find_dma(iommu, unmap->iova, unmap->size))) {
- if (!iommu->v2 && unmap->iova > dma->iova)
- break;
- /*
- * Task with same address space who mapped this iova range is
- * allowed to unmap the iova range.
- */
- if (dma->task->mm != current->mm)
- break;
- if (!RB_EMPTY_ROOT(&dma->pfn_list)) {
- struct vfio_iommu_type1_dma_unmap nb_unmap;
- if (dma_last == dma) {
- BUG_ON(++retries > 10);
- } else {
- dma_last = dma;
- retries = 0;
- }
- nb_unmap.iova = dma->iova;
- nb_unmap.size = dma->size;
- /*
- * Notify anyone (mdev vendor drivers) to invalidate and
- * unmap iovas within the range we're about to unmap.
- * Vendor drivers MUST unpin pages in response to an
- * invalidation.
- */
- mutex_unlock(&iommu->lock);
- blocking_notifier_call_chain(&iommu->notifier,
- VFIO_IOMMU_NOTIFY_DMA_UNMAP,
- &nb_unmap);
- mutex_lock(&iommu->lock);
- goto again;
- }
- if (unmap->flags & VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP) {
- ret = update_user_bitmap(bitmap->data, iommu, dma,
- unmap->iova, pgsize);
- if (ret)
- break;
- }
- unmapped += dma->size;
- vfio_remove_dma(iommu, dma);
- }
- unlock:
- mutex_unlock(&iommu->lock);
- /* Report how much was unmapped */
- unmap->size = unmapped;
- return ret;
- }
- static int vfio_iommu_map(struct vfio_iommu *iommu, dma_addr_t iova,
- unsigned long pfn, long npage, int prot)
- {
- struct vfio_domain *d;
- int ret;
- list_for_each_entry(d, &iommu->domain_list, next) {
- ret = iommu_map(d->domain, iova, (phys_addr_t)pfn << PAGE_SHIFT,
- npage << PAGE_SHIFT, prot | d->prot);
- if (ret)
- goto unwind;
- cond_resched();
- }
- return 0;
- unwind:
- list_for_each_entry_continue_reverse(d, &iommu->domain_list, next) {
- iommu_unmap(d->domain, iova, npage << PAGE_SHIFT);
- cond_resched();
- }
- return ret;
- }
- static int vfio_pin_map_dma(struct vfio_iommu *iommu, struct vfio_dma *dma,
- size_t map_size)
- {
- dma_addr_t iova = dma->iova;
- unsigned long vaddr = dma->vaddr;
- size_t size = map_size;
- long npage;
- unsigned long pfn, limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
- int ret = 0;
- while (size) {
- /* Pin a contiguous chunk of memory */
- npage = vfio_pin_pages_remote(dma, vaddr + dma->size,
- size >> PAGE_SHIFT, &pfn, limit);
- if (npage <= 0) {
- WARN_ON(!npage);
- ret = (int)npage;
- break;
- }
- /* Map it! */
- ret = vfio_iommu_map(iommu, iova + dma->size, pfn, npage,
- dma->prot);
- if (ret) {
- vfio_unpin_pages_remote(dma, iova + dma->size, pfn,
- npage, true);
- break;
- }
- size -= npage << PAGE_SHIFT;
- dma->size += npage << PAGE_SHIFT;
- }
- dma->iommu_mapped = true;
- if (ret)
- vfio_remove_dma(iommu, dma);
- return ret;
- }
- /*
- * Check dma map request is within a valid iova range
- */
- static bool vfio_iommu_iova_dma_valid(struct vfio_iommu *iommu,
- dma_addr_t start, dma_addr_t end)
- {
- struct list_head *iova = &iommu->iova_list;
- struct vfio_iova *node;
- list_for_each_entry(node, iova, list) {
- if (start >= node->start && end <= node->end)
- return true;
- }
- /*
- * Check for list_empty() as well since a container with
- * a single mdev device will have an empty list.
- */
- return list_empty(iova);
- }
- static int vfio_dma_do_map(struct vfio_iommu *iommu,
- struct vfio_iommu_type1_dma_map *map)
- {
- dma_addr_t iova = map->iova;
- unsigned long vaddr = map->vaddr;
- size_t size = map->size;
- int ret = 0, prot = 0;
- size_t pgsize;
- struct vfio_dma *dma;
- /* Verify that none of our __u64 fields overflow */
- if (map->size != size || map->vaddr != vaddr || map->iova != iova)
- return -EINVAL;
- /* READ/WRITE from device perspective */
- if (map->flags & VFIO_DMA_MAP_FLAG_WRITE)
- prot |= IOMMU_WRITE;
- if (map->flags & VFIO_DMA_MAP_FLAG_READ)
- prot |= IOMMU_READ;
- mutex_lock(&iommu->lock);
- pgsize = (size_t)1 << __ffs(iommu->pgsize_bitmap);
- WARN_ON((pgsize - 1) & PAGE_MASK);
- if (!prot || !size || (size | iova | vaddr) & (pgsize - 1)) {
- ret = -EINVAL;
- goto out_unlock;
- }
- /* Don't allow IOVA or virtual address wrap */
- if (iova + size - 1 < iova || vaddr + size - 1 < vaddr) {
- ret = -EINVAL;
- goto out_unlock;
- }
- if (vfio_find_dma(iommu, iova, size)) {
- ret = -EEXIST;
- goto out_unlock;
- }
- if (!iommu->dma_avail) {
- ret = -ENOSPC;
- goto out_unlock;
- }
- if (!vfio_iommu_iova_dma_valid(iommu, iova, iova + size - 1)) {
- ret = -EINVAL;
- goto out_unlock;
- }
- dma = kzalloc(sizeof(*dma), GFP_KERNEL);
- if (!dma) {
- ret = -ENOMEM;
- goto out_unlock;
- }
- iommu->dma_avail--;
- dma->iova = iova;
- dma->vaddr = vaddr;
- dma->prot = prot;
- /*
- * We need to be able to both add to a task's locked memory and test
- * against the locked memory limit and we need to be able to do both
- * outside of this call path as pinning can be asynchronous via the
- * external interfaces for mdev devices. RLIMIT_MEMLOCK requires a
- * task_struct and VM locked pages requires an mm_struct, however
- * holding an indefinite mm reference is not recommended, therefore we
- * only hold a reference to a task. We could hold a reference to
- * current, however QEMU uses this call path through vCPU threads,
- * which can be killed resulting in a NULL mm and failure in the unmap
- * path when called via a different thread. Avoid this problem by
- * using the group_leader as threads within the same group require
- * both CLONE_THREAD and CLONE_VM and will therefore use the same
- * mm_struct.
- *
- * Previously we also used the task for testing CAP_IPC_LOCK at the
- * time of pinning and accounting, however has_capability() makes use
- * of real_cred, a copy-on-write field, so we can't guarantee that it
- * matches group_leader, or in fact that it might not change by the
- * time it's evaluated. If a process were to call MAP_DMA with
- * CAP_IPC_LOCK but later drop it, it doesn't make sense that they
- * possibly see different results for an iommu_mapped vfio_dma vs
- * externally mapped. Therefore track CAP_IPC_LOCK in vfio_dma at the
- * time of calling MAP_DMA.
- */
- get_task_struct(current->group_leader);
- dma->task = current->group_leader;
- dma->lock_cap = capable(CAP_IPC_LOCK);
- dma->pfn_list = RB_ROOT;
- /* Insert zero-sized and grow as we map chunks of it */
- vfio_link_dma(iommu, dma);
- /* Don't pin and map if container doesn't contain IOMMU capable domain*/
- if (!IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu))
- dma->size = size;
- else
- ret = vfio_pin_map_dma(iommu, dma, size);
- if (!ret && iommu->dirty_page_tracking) {
- ret = vfio_dma_bitmap_alloc(dma, pgsize);
- if (ret)
- vfio_remove_dma(iommu, dma);
- }
- out_unlock:
- mutex_unlock(&iommu->lock);
- return ret;
- }
- static int vfio_bus_type(struct device *dev, void *data)
- {
- struct bus_type **bus = data;
- if (*bus && *bus != dev->bus)
- return -EINVAL;
- *bus = dev->bus;
- return 0;
- }
- static int vfio_iommu_replay(struct vfio_iommu *iommu,
- struct vfio_domain *domain)
- {
- struct vfio_domain *d = NULL;
- struct rb_node *n;
- unsigned long limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
- int ret;
- /* Arbitrarily pick the first domain in the list for lookups */
- if (!list_empty(&iommu->domain_list))
- d = list_first_entry(&iommu->domain_list,
- struct vfio_domain, next);
- n = rb_first(&iommu->dma_list);
- for (; n; n = rb_next(n)) {
- struct vfio_dma *dma;
- dma_addr_t iova;
- dma = rb_entry(n, struct vfio_dma, node);
- iova = dma->iova;
- while (iova < dma->iova + dma->size) {
- phys_addr_t phys;
- size_t size;
- if (dma->iommu_mapped) {
- phys_addr_t p;
- dma_addr_t i;
- if (WARN_ON(!d)) { /* mapped w/o a domain?! */
- ret = -EINVAL;
- goto unwind;
- }
- phys = iommu_iova_to_phys(d->domain, iova);
- if (WARN_ON(!phys)) {
- iova += PAGE_SIZE;
- continue;
- }
- size = PAGE_SIZE;
- p = phys + size;
- i = iova + size;
- while (i < dma->iova + dma->size &&
- p == iommu_iova_to_phys(d->domain, i)) {
- size += PAGE_SIZE;
- p += PAGE_SIZE;
- i += PAGE_SIZE;
- }
- } else {
- unsigned long pfn;
- unsigned long vaddr = dma->vaddr +
- (iova - dma->iova);
- size_t n = dma->iova + dma->size - iova;
- long npage;
- npage = vfio_pin_pages_remote(dma, vaddr,
- n >> PAGE_SHIFT,
- &pfn, limit);
- if (npage <= 0) {
- WARN_ON(!npage);
- ret = (int)npage;
- goto unwind;
- }
- phys = pfn << PAGE_SHIFT;
- size = npage << PAGE_SHIFT;
- }
- ret = iommu_map(domain->domain, iova, phys,
- size, dma->prot | domain->prot);
- if (ret) {
- if (!dma->iommu_mapped)
- vfio_unpin_pages_remote(dma, iova,
- phys >> PAGE_SHIFT,
- size >> PAGE_SHIFT,
- true);
- goto unwind;
- }
- iova += size;
- }
- }
- /* All dmas are now mapped, defer to second tree walk for unwind */
- for (n = rb_first(&iommu->dma_list); n; n = rb_next(n)) {
- struct vfio_dma *dma = rb_entry(n, struct vfio_dma, node);
- dma->iommu_mapped = true;
- }
- return 0;
- unwind:
- for (; n; n = rb_prev(n)) {
- struct vfio_dma *dma = rb_entry(n, struct vfio_dma, node);
- dma_addr_t iova;
- if (dma->iommu_mapped) {
- iommu_unmap(domain->domain, dma->iova, dma->size);
- continue;
- }
- iova = dma->iova;
- while (iova < dma->iova + dma->size) {
- phys_addr_t phys, p;
- size_t size;
- dma_addr_t i;
- phys = iommu_iova_to_phys(domain->domain, iova);
- if (!phys) {
- iova += PAGE_SIZE;
- continue;
- }
- size = PAGE_SIZE;
- p = phys + size;
- i = iova + size;
- while (i < dma->iova + dma->size &&
- p == iommu_iova_to_phys(domain->domain, i)) {
- size += PAGE_SIZE;
- p += PAGE_SIZE;
- i += PAGE_SIZE;
- }
- iommu_unmap(domain->domain, iova, size);
- vfio_unpin_pages_remote(dma, iova, phys >> PAGE_SHIFT,
- size >> PAGE_SHIFT, true);
- }
- }
- return ret;
- }
- /*
- * We change our unmap behavior slightly depending on whether the IOMMU
- * supports fine-grained superpages. IOMMUs like AMD-Vi will use a superpage
- * for practically any contiguous power-of-two mapping we give it. This means
- * we don't need to look for contiguous chunks ourselves to make unmapping
- * more efficient. On IOMMUs with coarse-grained super pages, like Intel VT-d
- * with discrete 2M/1G/512G/1T superpages, identifying contiguous chunks
- * significantly boosts non-hugetlbfs mappings and doesn't seem to hurt when
- * hugetlbfs is in use.
- */
- static void vfio_test_domain_fgsp(struct vfio_domain *domain)
- {
- struct page *pages;
- int ret, order = get_order(PAGE_SIZE * 2);
- pages = alloc_pages(GFP_KERNEL | __GFP_ZERO, order);
- if (!pages)
- return;
- ret = iommu_map(domain->domain, 0, page_to_phys(pages), PAGE_SIZE * 2,
- IOMMU_READ | IOMMU_WRITE | domain->prot);
- if (!ret) {
- size_t unmapped = iommu_unmap(domain->domain, 0, PAGE_SIZE);
- if (unmapped == PAGE_SIZE)
- iommu_unmap(domain->domain, PAGE_SIZE, PAGE_SIZE);
- else
- domain->fgsp = true;
- }
- __free_pages(pages, order);
- }
- static struct vfio_group *find_iommu_group(struct vfio_domain *domain,
- struct iommu_group *iommu_group)
- {
- struct vfio_group *g;
- list_for_each_entry(g, &domain->group_list, next) {
- if (g->iommu_group == iommu_group)
- return g;
- }
- return NULL;
- }
- static struct vfio_group *vfio_iommu_find_iommu_group(struct vfio_iommu *iommu,
- struct iommu_group *iommu_group)
- {
- struct vfio_domain *domain;
- struct vfio_group *group = NULL;
- list_for_each_entry(domain, &iommu->domain_list, next) {
- group = find_iommu_group(domain, iommu_group);
- if (group)
- return group;
- }
- if (iommu->external_domain)
- group = find_iommu_group(iommu->external_domain, iommu_group);
- return group;
- }
- static void update_pinned_page_dirty_scope(struct vfio_iommu *iommu)
- {
- struct vfio_domain *domain;
- struct vfio_group *group;
- list_for_each_entry(domain, &iommu->domain_list, next) {
- list_for_each_entry(group, &domain->group_list, next) {
- if (!group->pinned_page_dirty_scope) {
- iommu->pinned_page_dirty_scope = false;
- return;
- }
- }
- }
- if (iommu->external_domain) {
- domain = iommu->external_domain;
- list_for_each_entry(group, &domain->group_list, next) {
- if (!group->pinned_page_dirty_scope) {
- iommu->pinned_page_dirty_scope = false;
- return;
- }
- }
- }
- iommu->pinned_page_dirty_scope = true;
- }
- static bool vfio_iommu_has_sw_msi(struct list_head *group_resv_regions,
- phys_addr_t *base)
- {
- struct iommu_resv_region *region;
- bool ret = false;
- list_for_each_entry(region, group_resv_regions, list) {
- /*
- * The presence of any 'real' MSI regions should take
- * precedence over the software-managed one if the
- * IOMMU driver happens to advertise both types.
- */
- if (region->type == IOMMU_RESV_MSI) {
- ret = false;
- break;
- }
- if (region->type == IOMMU_RESV_SW_MSI) {
- *base = region->start;
- ret = true;
- }
- }
- return ret;
- }
- static struct device *vfio_mdev_get_iommu_device(struct device *dev)
- {
- struct device *(*fn)(struct device *dev);
- struct device *iommu_device;
- fn = symbol_get(mdev_get_iommu_device);
- if (fn) {
- iommu_device = fn(dev);
- symbol_put(mdev_get_iommu_device);
- return iommu_device;
- }
- return NULL;
- }
- static int vfio_mdev_attach_domain(struct device *dev, void *data)
- {
- struct iommu_domain *domain = data;
- struct device *iommu_device;
- iommu_device = vfio_mdev_get_iommu_device(dev);
- if (iommu_device) {
- if (iommu_dev_feature_enabled(iommu_device, IOMMU_DEV_FEAT_AUX))
- return iommu_aux_attach_device(domain, iommu_device);
- else
- return iommu_attach_device(domain, iommu_device);
- }
- return -EINVAL;
- }
- static int vfio_mdev_detach_domain(struct device *dev, void *data)
- {
- struct iommu_domain *domain = data;
- struct device *iommu_device;
- iommu_device = vfio_mdev_get_iommu_device(dev);
- if (iommu_device) {
- if (iommu_dev_feature_enabled(iommu_device, IOMMU_DEV_FEAT_AUX))
- iommu_aux_detach_device(domain, iommu_device);
- else
- iommu_detach_device(domain, iommu_device);
- }
- return 0;
- }
- static int vfio_iommu_attach_group(struct vfio_domain *domain,
- struct vfio_group *group)
- {
- if (group->mdev_group)
- return iommu_group_for_each_dev(group->iommu_group,
- domain->domain,
- vfio_mdev_attach_domain);
- else
- return iommu_attach_group(domain->domain, group->iommu_group);
- }
- static void vfio_iommu_detach_group(struct vfio_domain *domain,
- struct vfio_group *group)
- {
- if (group->mdev_group)
- iommu_group_for_each_dev(group->iommu_group, domain->domain,
- vfio_mdev_detach_domain);
- else
- iommu_detach_group(domain->domain, group->iommu_group);
- }
- static bool vfio_bus_is_mdev(struct bus_type *bus)
- {
- struct bus_type *mdev_bus;
- bool ret = false;
- mdev_bus = symbol_get(mdev_bus_type);
- if (mdev_bus) {
- ret = (bus == mdev_bus);
- symbol_put(mdev_bus_type);
- }
- return ret;
- }
- static int vfio_mdev_iommu_device(struct device *dev, void *data)
- {
- struct device **old = data, *new;
- new = vfio_mdev_get_iommu_device(dev);
- if (!new || (*old && *old != new))
- return -EINVAL;
- *old = new;
- return 0;
- }
- /*
- * This is a helper function to insert an address range to iova list.
- * The list is initially created with a single entry corresponding to
- * the IOMMU domain geometry to which the device group is attached.
- * The list aperture gets modified when a new domain is added to the
- * container if the new aperture doesn't conflict with the current one
- * or with any existing dma mappings. The list is also modified to
- * exclude any reserved regions associated with the device group.
- */
- static int vfio_iommu_iova_insert(struct list_head *head,
- dma_addr_t start, dma_addr_t end)
- {
- struct vfio_iova *region;
- region = kmalloc(sizeof(*region), GFP_KERNEL);
- if (!region)
- return -ENOMEM;
- INIT_LIST_HEAD(®ion->list);
- region->start = start;
- region->end = end;
- list_add_tail(®ion->list, head);
- return 0;
- }
- /*
- * Check the new iommu aperture conflicts with existing aper or with any
- * existing dma mappings.
- */
- static bool vfio_iommu_aper_conflict(struct vfio_iommu *iommu,
- dma_addr_t start, dma_addr_t end)
- {
- struct vfio_iova *first, *last;
- struct list_head *iova = &iommu->iova_list;
- if (list_empty(iova))
- return false;
- /* Disjoint sets, return conflict */
- first = list_first_entry(iova, struct vfio_iova, list);
- last = list_last_entry(iova, struct vfio_iova, list);
- if (start > last->end || end < first->start)
- return true;
- /* Check for any existing dma mappings below the new start */
- if (start > first->start) {
- if (vfio_find_dma(iommu, first->start, start - first->start))
- return true;
- }
- /* Check for any existing dma mappings beyond the new end */
- if (end < last->end) {
- if (vfio_find_dma(iommu, end + 1, last->end - end))
- return true;
- }
- return false;
- }
- /*
- * Resize iommu iova aperture window. This is called only if the new
- * aperture has no conflict with existing aperture and dma mappings.
- */
- static int vfio_iommu_aper_resize(struct list_head *iova,
- dma_addr_t start, dma_addr_t end)
- {
- struct vfio_iova *node, *next;
- if (list_empty(iova))
- return vfio_iommu_iova_insert(iova, start, end);
- /* Adjust iova list start */
- list_for_each_entry_safe(node, next, iova, list) {
- if (start < node->start)
- break;
- if (start >= node->start && start < node->end) {
- node->start = start;
- break;
- }
- /* Delete nodes before new start */
- list_del(&node->list);
- kfree(node);
- }
- /* Adjust iova list end */
- list_for_each_entry_safe(node, next, iova, list) {
- if (end > node->end)
- continue;
- if (end > node->start && end <= node->end) {
- node->end = end;
- continue;
- }
- /* Delete nodes after new end */
- list_del(&node->list);
- kfree(node);
- }
- return 0;
- }
- /*
- * Check reserved region conflicts with existing dma mappings
- */
- static bool vfio_iommu_resv_conflict(struct vfio_iommu *iommu,
- struct list_head *resv_regions)
- {
- struct iommu_resv_region *region;
- /* Check for conflict with existing dma mappings */
- list_for_each_entry(region, resv_regions, list) {
- if (region->type == IOMMU_RESV_DIRECT_RELAXABLE)
- continue;
- if (vfio_find_dma(iommu, region->start, region->length))
- return true;
- }
- return false;
- }
- /*
- * Check iova region overlap with reserved regions and
- * exclude them from the iommu iova range
- */
- static int vfio_iommu_resv_exclude(struct list_head *iova,
- struct list_head *resv_regions)
- {
- struct iommu_resv_region *resv;
- struct vfio_iova *n, *next;
- list_for_each_entry(resv, resv_regions, list) {
- phys_addr_t start, end;
- if (resv->type == IOMMU_RESV_DIRECT_RELAXABLE)
- continue;
- start = resv->start;
- end = resv->start + resv->length - 1;
- list_for_each_entry_safe(n, next, iova, list) {
- int ret = 0;
- /* No overlap */
- if (start > n->end || end < n->start)
- continue;
- /*
- * Insert a new node if current node overlaps with the
- * reserve region to exlude that from valid iova range.
- * Note that, new node is inserted before the current
- * node and finally the current node is deleted keeping
- * the list updated and sorted.
- */
- if (start > n->start)
- ret = vfio_iommu_iova_insert(&n->list, n->start,
- start - 1);
- if (!ret && end < n->end)
- ret = vfio_iommu_iova_insert(&n->list, end + 1,
- n->end);
- if (ret)
- return ret;
- list_del(&n->list);
- kfree(n);
- }
- }
- if (list_empty(iova))
- return -EINVAL;
- return 0;
- }
- static void vfio_iommu_resv_free(struct list_head *resv_regions)
- {
- struct iommu_resv_region *n, *next;
- list_for_each_entry_safe(n, next, resv_regions, list) {
- list_del(&n->list);
- kfree(n);
- }
- }
- static void vfio_iommu_iova_free(struct list_head *iova)
- {
- struct vfio_iova *n, *next;
- list_for_each_entry_safe(n, next, iova, list) {
- list_del(&n->list);
- kfree(n);
- }
- }
- static int vfio_iommu_iova_get_copy(struct vfio_iommu *iommu,
- struct list_head *iova_copy)
- {
- struct list_head *iova = &iommu->iova_list;
- struct vfio_iova *n;
- int ret;
- list_for_each_entry(n, iova, list) {
- ret = vfio_iommu_iova_insert(iova_copy, n->start, n->end);
- if (ret)
- goto out_free;
- }
- return 0;
- out_free:
- vfio_iommu_iova_free(iova_copy);
- return ret;
- }
- static void vfio_iommu_iova_insert_copy(struct vfio_iommu *iommu,
- struct list_head *iova_copy)
- {
- struct list_head *iova = &iommu->iova_list;
- vfio_iommu_iova_free(iova);
- list_splice_tail(iova_copy, iova);
- }
- static int vfio_iommu_type1_attach_group(void *iommu_data,
- struct iommu_group *iommu_group)
- {
- struct vfio_iommu *iommu = iommu_data;
- struct vfio_group *group;
- struct vfio_domain *domain, *d;
- struct bus_type *bus = NULL;
- int ret;
- bool resv_msi, msi_remap;
- phys_addr_t resv_msi_base = 0;
- struct iommu_domain_geometry geo;
- LIST_HEAD(iova_copy);
- LIST_HEAD(group_resv_regions);
- mutex_lock(&iommu->lock);
- /* Check for duplicates */
- if (vfio_iommu_find_iommu_group(iommu, iommu_group)) {
- mutex_unlock(&iommu->lock);
- return -EINVAL;
- }
- group = kzalloc(sizeof(*group), GFP_KERNEL);
- domain = kzalloc(sizeof(*domain), GFP_KERNEL);
- if (!group || !domain) {
- ret = -ENOMEM;
- goto out_free;
- }
- group->iommu_group = iommu_group;
- /* Determine bus_type in order to allocate a domain */
- ret = iommu_group_for_each_dev(iommu_group, &bus, vfio_bus_type);
- if (ret)
- goto out_free;
- if (vfio_bus_is_mdev(bus)) {
- struct device *iommu_device = NULL;
- group->mdev_group = true;
- /* Determine the isolation type */
- ret = iommu_group_for_each_dev(iommu_group, &iommu_device,
- vfio_mdev_iommu_device);
- if (ret || !iommu_device) {
- if (!iommu->external_domain) {
- INIT_LIST_HEAD(&domain->group_list);
- iommu->external_domain = domain;
- vfio_update_pgsize_bitmap(iommu);
- } else {
- kfree(domain);
- }
- list_add(&group->next,
- &iommu->external_domain->group_list);
- /*
- * Non-iommu backed group cannot dirty memory directly,
- * it can only use interfaces that provide dirty
- * tracking.
- * The iommu scope can only be promoted with the
- * addition of a dirty tracking group.
- */
- group->pinned_page_dirty_scope = true;
- if (!iommu->pinned_page_dirty_scope)
- update_pinned_page_dirty_scope(iommu);
- mutex_unlock(&iommu->lock);
- return 0;
- }
- bus = iommu_device->bus;
- }
- domain->domain = iommu_domain_alloc(bus);
- if (!domain->domain) {
- ret = -EIO;
- goto out_free;
- }
- if (iommu->nesting) {
- int attr = 1;
- ret = iommu_domain_set_attr(domain->domain, DOMAIN_ATTR_NESTING,
- &attr);
- if (ret)
- goto out_domain;
- }
- ret = vfio_iommu_attach_group(domain, group);
- if (ret)
- goto out_domain;
- /* Get aperture info */
- iommu_domain_get_attr(domain->domain, DOMAIN_ATTR_GEOMETRY, &geo);
- if (vfio_iommu_aper_conflict(iommu, geo.aperture_start,
- geo.aperture_end)) {
- ret = -EINVAL;
- goto out_detach;
- }
- ret = iommu_get_group_resv_regions(iommu_group, &group_resv_regions);
- if (ret)
- goto out_detach;
- if (vfio_iommu_resv_conflict(iommu, &group_resv_regions)) {
- ret = -EINVAL;
- goto out_detach;
- }
- /*
- * We don't want to work on the original iova list as the list
- * gets modified and in case of failure we have to retain the
- * original list. Get a copy here.
- */
- ret = vfio_iommu_iova_get_copy(iommu, &iova_copy);
- if (ret)
- goto out_detach;
- ret = vfio_iommu_aper_resize(&iova_copy, geo.aperture_start,
- geo.aperture_end);
- if (ret)
- goto out_detach;
- ret = vfio_iommu_resv_exclude(&iova_copy, &group_resv_regions);
- if (ret)
- goto out_detach;
- resv_msi = vfio_iommu_has_sw_msi(&group_resv_regions, &resv_msi_base);
- INIT_LIST_HEAD(&domain->group_list);
- list_add(&group->next, &domain->group_list);
- msi_remap = irq_domain_check_msi_remap() ||
- iommu_capable(bus, IOMMU_CAP_INTR_REMAP);
- if (!allow_unsafe_interrupts && !msi_remap) {
- pr_warn("%s: No interrupt remapping support. Use the module param \"allow_unsafe_interrupts\" to enable VFIO IOMMU support on this platform\n",
- __func__);
- ret = -EPERM;
- goto out_detach;
- }
- if (iommu_capable(bus, IOMMU_CAP_CACHE_COHERENCY))
- domain->prot |= IOMMU_CACHE;
- /*
- * Try to match an existing compatible domain. We don't want to
- * preclude an IOMMU driver supporting multiple bus_types and being
- * able to include different bus_types in the same IOMMU domain, so
- * we test whether the domains use the same iommu_ops rather than
- * testing if they're on the same bus_type.
- */
- list_for_each_entry(d, &iommu->domain_list, next) {
- if (d->domain->ops == domain->domain->ops &&
- d->prot == domain->prot) {
- vfio_iommu_detach_group(domain, group);
- if (!vfio_iommu_attach_group(d, group)) {
- list_add(&group->next, &d->group_list);
- iommu_domain_free(domain->domain);
- kfree(domain);
- goto done;
- }
- ret = vfio_iommu_attach_group(domain, group);
- if (ret)
- goto out_domain;
- }
- }
- vfio_test_domain_fgsp(domain);
- /* replay mappings on new domains */
- ret = vfio_iommu_replay(iommu, domain);
- if (ret)
- goto out_detach;
- if (resv_msi) {
- ret = iommu_get_msi_cookie(domain->domain, resv_msi_base);
- if (ret && ret != -ENODEV)
- goto out_detach;
- }
- list_add(&domain->next, &iommu->domain_list);
- vfio_update_pgsize_bitmap(iommu);
- done:
- /* Delete the old one and insert new iova list */
- vfio_iommu_iova_insert_copy(iommu, &iova_copy);
- /*
- * An iommu backed group can dirty memory directly and therefore
- * demotes the iommu scope until it declares itself dirty tracking
- * capable via the page pinning interface.
- */
- iommu->pinned_page_dirty_scope = false;
- mutex_unlock(&iommu->lock);
- vfio_iommu_resv_free(&group_resv_regions);
- return 0;
- out_detach:
- vfio_iommu_detach_group(domain, group);
- out_domain:
- iommu_domain_free(domain->domain);
- vfio_iommu_iova_free(&iova_copy);
- vfio_iommu_resv_free(&group_resv_regions);
- out_free:
- kfree(domain);
- kfree(group);
- mutex_unlock(&iommu->lock);
- return ret;
- }
- static void vfio_iommu_unmap_unpin_all(struct vfio_iommu *iommu)
- {
- struct rb_node *node;
- while ((node = rb_first(&iommu->dma_list)))
- vfio_remove_dma(iommu, rb_entry(node, struct vfio_dma, node));
- }
- static void vfio_iommu_unmap_unpin_reaccount(struct vfio_iommu *iommu)
- {
- struct rb_node *n, *p;
- n = rb_first(&iommu->dma_list);
- for (; n; n = rb_next(n)) {
- struct vfio_dma *dma;
- long locked = 0, unlocked = 0;
- dma = rb_entry(n, struct vfio_dma, node);
- unlocked += vfio_unmap_unpin(iommu, dma, false);
- p = rb_first(&dma->pfn_list);
- for (; p; p = rb_next(p)) {
- struct vfio_pfn *vpfn = rb_entry(p, struct vfio_pfn,
- node);
- if (!is_invalid_reserved_pfn(vpfn->pfn))
- locked++;
- }
- vfio_lock_acct(dma, locked - unlocked, true);
- }
- }
- /*
- * Called when a domain is removed in detach. It is possible that
- * the removed domain decided the iova aperture window. Modify the
- * iova aperture with the smallest window among existing domains.
- */
- static void vfio_iommu_aper_expand(struct vfio_iommu *iommu,
- struct list_head *iova_copy)
- {
- struct vfio_domain *domain;
- struct iommu_domain_geometry geo;
- struct vfio_iova *node;
- dma_addr_t start = 0;
- dma_addr_t end = (dma_addr_t)~0;
- if (list_empty(iova_copy))
- return;
- list_for_each_entry(domain, &iommu->domain_list, next) {
- iommu_domain_get_attr(domain->domain, DOMAIN_ATTR_GEOMETRY,
- &geo);
- if (geo.aperture_start > start)
- start = geo.aperture_start;
- if (geo.aperture_end < end)
- end = geo.aperture_end;
- }
- /* Modify aperture limits. The new aper is either same or bigger */
- node = list_first_entry(iova_copy, struct vfio_iova, list);
- node->start = start;
- node = list_last_entry(iova_copy, struct vfio_iova, list);
- node->end = end;
- }
- /*
- * Called when a group is detached. The reserved regions for that
- * group can be part of valid iova now. But since reserved regions
- * may be duplicated among groups, populate the iova valid regions
- * list again.
- */
- static int vfio_iommu_resv_refresh(struct vfio_iommu *iommu,
- struct list_head *iova_copy)
- {
- struct vfio_domain *d;
- struct vfio_group *g;
- struct vfio_iova *node;
- dma_addr_t start, end;
- LIST_HEAD(resv_regions);
- int ret;
- if (list_empty(iova_copy))
- return -EINVAL;
- list_for_each_entry(d, &iommu->domain_list, next) {
- list_for_each_entry(g, &d->group_list, next) {
- ret = iommu_get_group_resv_regions(g->iommu_group,
- &resv_regions);
- if (ret)
- goto done;
- }
- }
- node = list_first_entry(iova_copy, struct vfio_iova, list);
- start = node->start;
- node = list_last_entry(iova_copy, struct vfio_iova, list);
- end = node->end;
- /* purge the iova list and create new one */
- vfio_iommu_iova_free(iova_copy);
- ret = vfio_iommu_aper_resize(iova_copy, start, end);
- if (ret)
- goto done;
- /* Exclude current reserved regions from iova ranges */
- ret = vfio_iommu_resv_exclude(iova_copy, &resv_regions);
- done:
- vfio_iommu_resv_free(&resv_regions);
- return ret;
- }
- static void vfio_iommu_type1_detach_group(void *iommu_data,
- struct iommu_group *iommu_group)
- {
- struct vfio_iommu *iommu = iommu_data;
- struct vfio_domain *domain;
- struct vfio_group *group;
- bool update_dirty_scope = false;
- LIST_HEAD(iova_copy);
- mutex_lock(&iommu->lock);
- if (iommu->external_domain) {
- group = find_iommu_group(iommu->external_domain, iommu_group);
- if (group) {
- update_dirty_scope = !group->pinned_page_dirty_scope;
- list_del(&group->next);
- kfree(group);
- if (list_empty(&iommu->external_domain->group_list)) {
- if (!IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu)) {
- WARN_ON(iommu->notifier.head);
- vfio_iommu_unmap_unpin_all(iommu);
- }
- kfree(iommu->external_domain);
- iommu->external_domain = NULL;
- }
- goto detach_group_done;
- }
- }
- /*
- * Get a copy of iova list. This will be used to update
- * and to replace the current one later. Please note that
- * we will leave the original list as it is if update fails.
- */
- vfio_iommu_iova_get_copy(iommu, &iova_copy);
- list_for_each_entry(domain, &iommu->domain_list, next) {
- group = find_iommu_group(domain, iommu_group);
- if (!group)
- continue;
- vfio_iommu_detach_group(domain, group);
- update_dirty_scope = !group->pinned_page_dirty_scope;
- list_del(&group->next);
- kfree(group);
- /*
- * Group ownership provides privilege, if the group list is
- * empty, the domain goes away. If it's the last domain with
- * iommu and external domain doesn't exist, then all the
- * mappings go away too. If it's the last domain with iommu and
- * external domain exist, update accounting
- */
- if (list_empty(&domain->group_list)) {
- if (list_is_singular(&iommu->domain_list)) {
- if (!iommu->external_domain) {
- WARN_ON(iommu->notifier.head);
- vfio_iommu_unmap_unpin_all(iommu);
- } else {
- vfio_iommu_unmap_unpin_reaccount(iommu);
- }
- }
- iommu_domain_free(domain->domain);
- list_del(&domain->next);
- kfree(domain);
- vfio_iommu_aper_expand(iommu, &iova_copy);
- vfio_update_pgsize_bitmap(iommu);
- }
- break;
- }
- if (!vfio_iommu_resv_refresh(iommu, &iova_copy))
- vfio_iommu_iova_insert_copy(iommu, &iova_copy);
- else
- vfio_iommu_iova_free(&iova_copy);
- detach_group_done:
- /*
- * Removal of a group without dirty tracking may allow the iommu scope
- * to be promoted.
- */
- if (update_dirty_scope) {
- update_pinned_page_dirty_scope(iommu);
- if (iommu->dirty_page_tracking)
- vfio_iommu_populate_bitmap_full(iommu);
- }
- mutex_unlock(&iommu->lock);
- }
- static void *vfio_iommu_type1_open(unsigned long arg)
- {
- struct vfio_iommu *iommu;
- iommu = kzalloc(sizeof(*iommu), GFP_KERNEL);
- if (!iommu)
- return ERR_PTR(-ENOMEM);
- switch (arg) {
- case VFIO_TYPE1_IOMMU:
- break;
- case VFIO_TYPE1_NESTING_IOMMU:
- iommu->nesting = true;
- fallthrough;
- case VFIO_TYPE1v2_IOMMU:
- iommu->v2 = true;
- break;
- default:
- kfree(iommu);
- return ERR_PTR(-EINVAL);
- }
- INIT_LIST_HEAD(&iommu->domain_list);
- INIT_LIST_HEAD(&iommu->iova_list);
- iommu->dma_list = RB_ROOT;
- iommu->dma_avail = dma_entry_limit;
- mutex_init(&iommu->lock);
- BLOCKING_INIT_NOTIFIER_HEAD(&iommu->notifier);
- return iommu;
- }
- static void vfio_release_domain(struct vfio_domain *domain, bool external)
- {
- struct vfio_group *group, *group_tmp;
- list_for_each_entry_safe(group, group_tmp,
- &domain->group_list, next) {
- if (!external)
- vfio_iommu_detach_group(domain, group);
- list_del(&group->next);
- kfree(group);
- }
- if (!external)
- iommu_domain_free(domain->domain);
- }
- static void vfio_iommu_type1_release(void *iommu_data)
- {
- struct vfio_iommu *iommu = iommu_data;
- struct vfio_domain *domain, *domain_tmp;
- if (iommu->external_domain) {
- vfio_release_domain(iommu->external_domain, true);
- kfree(iommu->external_domain);
- }
- vfio_iommu_unmap_unpin_all(iommu);
- list_for_each_entry_safe(domain, domain_tmp,
- &iommu->domain_list, next) {
- vfio_release_domain(domain, false);
- list_del(&domain->next);
- kfree(domain);
- }
- vfio_iommu_iova_free(&iommu->iova_list);
- kfree(iommu);
- }
- static int vfio_domains_have_iommu_cache(struct vfio_iommu *iommu)
- {
- struct vfio_domain *domain;
- int ret = 1;
- mutex_lock(&iommu->lock);
- list_for_each_entry(domain, &iommu->domain_list, next) {
- if (!(domain->prot & IOMMU_CACHE)) {
- ret = 0;
- break;
- }
- }
- mutex_unlock(&iommu->lock);
- return ret;
- }
- static int vfio_iommu_type1_check_extension(struct vfio_iommu *iommu,
- unsigned long arg)
- {
- switch (arg) {
- case VFIO_TYPE1_IOMMU:
- case VFIO_TYPE1v2_IOMMU:
- case VFIO_TYPE1_NESTING_IOMMU:
- return 1;
- case VFIO_DMA_CC_IOMMU:
- if (!iommu)
- return 0;
- return vfio_domains_have_iommu_cache(iommu);
- default:
- return 0;
- }
- }
- static int vfio_iommu_iova_add_cap(struct vfio_info_cap *caps,
- struct vfio_iommu_type1_info_cap_iova_range *cap_iovas,
- size_t size)
- {
- struct vfio_info_cap_header *header;
- struct vfio_iommu_type1_info_cap_iova_range *iova_cap;
- header = vfio_info_cap_add(caps, size,
- VFIO_IOMMU_TYPE1_INFO_CAP_IOVA_RANGE, 1);
- if (IS_ERR(header))
- return PTR_ERR(header);
- iova_cap = container_of(header,
- struct vfio_iommu_type1_info_cap_iova_range,
- header);
- iova_cap->nr_iovas = cap_iovas->nr_iovas;
- memcpy(iova_cap->iova_ranges, cap_iovas->iova_ranges,
- cap_iovas->nr_iovas * sizeof(*cap_iovas->iova_ranges));
- return 0;
- }
- static int vfio_iommu_iova_build_caps(struct vfio_iommu *iommu,
- struct vfio_info_cap *caps)
- {
- struct vfio_iommu_type1_info_cap_iova_range *cap_iovas;
- struct vfio_iova *iova;
- size_t size;
- int iovas = 0, i = 0, ret;
- list_for_each_entry(iova, &iommu->iova_list, list)
- iovas++;
- if (!iovas) {
- /*
- * Return 0 as a container with a single mdev device
- * will have an empty list
- */
- return 0;
- }
- size = sizeof(*cap_iovas) + (iovas * sizeof(*cap_iovas->iova_ranges));
- cap_iovas = kzalloc(size, GFP_KERNEL);
- if (!cap_iovas)
- return -ENOMEM;
- cap_iovas->nr_iovas = iovas;
- list_for_each_entry(iova, &iommu->iova_list, list) {
- cap_iovas->iova_ranges[i].start = iova->start;
- cap_iovas->iova_ranges[i].end = iova->end;
- i++;
- }
- ret = vfio_iommu_iova_add_cap(caps, cap_iovas, size);
- kfree(cap_iovas);
- return ret;
- }
- static int vfio_iommu_migration_build_caps(struct vfio_iommu *iommu,
- struct vfio_info_cap *caps)
- {
- struct vfio_iommu_type1_info_cap_migration cap_mig;
- cap_mig.header.id = VFIO_IOMMU_TYPE1_INFO_CAP_MIGRATION;
- cap_mig.header.version = 1;
- cap_mig.flags = 0;
- /* support minimum pgsize */
- cap_mig.pgsize_bitmap = (size_t)1 << __ffs(iommu->pgsize_bitmap);
- cap_mig.max_dirty_bitmap_size = DIRTY_BITMAP_SIZE_MAX;
- return vfio_info_add_capability(caps, &cap_mig.header, sizeof(cap_mig));
- }
- static int vfio_iommu_dma_avail_build_caps(struct vfio_iommu *iommu,
- struct vfio_info_cap *caps)
- {
- struct vfio_iommu_type1_info_dma_avail cap_dma_avail;
- cap_dma_avail.header.id = VFIO_IOMMU_TYPE1_INFO_DMA_AVAIL;
- cap_dma_avail.header.version = 1;
- cap_dma_avail.avail = iommu->dma_avail;
- return vfio_info_add_capability(caps, &cap_dma_avail.header,
- sizeof(cap_dma_avail));
- }
- static int vfio_iommu_type1_get_info(struct vfio_iommu *iommu,
- unsigned long arg)
- {
- struct vfio_iommu_type1_info info;
- unsigned long minsz;
- struct vfio_info_cap caps = { .buf = NULL, .size = 0 };
- unsigned long capsz;
- int ret;
- minsz = offsetofend(struct vfio_iommu_type1_info, iova_pgsizes);
- /* For backward compatibility, cannot require this */
- capsz = offsetofend(struct vfio_iommu_type1_info, cap_offset);
- if (copy_from_user(&info, (void __user *)arg, minsz))
- return -EFAULT;
- if (info.argsz < minsz)
- return -EINVAL;
- if (info.argsz >= capsz) {
- minsz = capsz;
- info.cap_offset = 0; /* output, no-recopy necessary */
- }
- mutex_lock(&iommu->lock);
- info.flags = VFIO_IOMMU_INFO_PGSIZES;
- info.iova_pgsizes = iommu->pgsize_bitmap;
- ret = vfio_iommu_migration_build_caps(iommu, &caps);
- if (!ret)
- ret = vfio_iommu_dma_avail_build_caps(iommu, &caps);
- if (!ret)
- ret = vfio_iommu_iova_build_caps(iommu, &caps);
- mutex_unlock(&iommu->lock);
- if (ret)
- return ret;
- if (caps.size) {
- info.flags |= VFIO_IOMMU_INFO_CAPS;
- if (info.argsz < sizeof(info) + caps.size) {
- info.argsz = sizeof(info) + caps.size;
- } else {
- vfio_info_cap_shift(&caps, sizeof(info));
- if (copy_to_user((void __user *)arg +
- sizeof(info), caps.buf,
- caps.size)) {
- kfree(caps.buf);
- return -EFAULT;
- }
- info.cap_offset = sizeof(info);
- }
- kfree(caps.buf);
- }
- return copy_to_user((void __user *)arg, &info, minsz) ?
- -EFAULT : 0;
- }
- static int vfio_iommu_type1_map_dma(struct vfio_iommu *iommu,
- unsigned long arg)
- {
- struct vfio_iommu_type1_dma_map map;
- unsigned long minsz;
- uint32_t mask = VFIO_DMA_MAP_FLAG_READ | VFIO_DMA_MAP_FLAG_WRITE;
- minsz = offsetofend(struct vfio_iommu_type1_dma_map, size);
- if (copy_from_user(&map, (void __user *)arg, minsz))
- return -EFAULT;
- if (map.argsz < minsz || map.flags & ~mask)
- return -EINVAL;
- return vfio_dma_do_map(iommu, &map);
- }
- static int vfio_iommu_type1_unmap_dma(struct vfio_iommu *iommu,
- unsigned long arg)
- {
- struct vfio_iommu_type1_dma_unmap unmap;
- struct vfio_bitmap bitmap = { 0 };
- unsigned long minsz;
- int ret;
- minsz = offsetofend(struct vfio_iommu_type1_dma_unmap, size);
- if (copy_from_user(&unmap, (void __user *)arg, minsz))
- return -EFAULT;
- if (unmap.argsz < minsz ||
- unmap.flags & ~VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP)
- return -EINVAL;
- if (unmap.flags & VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP) {
- unsigned long pgshift;
- if (unmap.argsz < (minsz + sizeof(bitmap)))
- return -EINVAL;
- if (copy_from_user(&bitmap,
- (void __user *)(arg + minsz),
- sizeof(bitmap)))
- return -EFAULT;
- if (!access_ok((void __user *)bitmap.data, bitmap.size))
- return -EINVAL;
- pgshift = __ffs(bitmap.pgsize);
- ret = verify_bitmap_size(unmap.size >> pgshift,
- bitmap.size);
- if (ret)
- return ret;
- }
- ret = vfio_dma_do_unmap(iommu, &unmap, &bitmap);
- if (ret)
- return ret;
- return copy_to_user((void __user *)arg, &unmap, minsz) ?
- -EFAULT : 0;
- }
- static int vfio_iommu_type1_dirty_pages(struct vfio_iommu *iommu,
- unsigned long arg)
- {
- struct vfio_iommu_type1_dirty_bitmap dirty;
- uint32_t mask = VFIO_IOMMU_DIRTY_PAGES_FLAG_START |
- VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP |
- VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP;
- unsigned long minsz;
- int ret = 0;
- if (!iommu->v2)
- return -EACCES;
- minsz = offsetofend(struct vfio_iommu_type1_dirty_bitmap, flags);
- if (copy_from_user(&dirty, (void __user *)arg, minsz))
- return -EFAULT;
- if (dirty.argsz < minsz || dirty.flags & ~mask)
- return -EINVAL;
- /* only one flag should be set at a time */
- if (__ffs(dirty.flags) != __fls(dirty.flags))
- return -EINVAL;
- if (dirty.flags & VFIO_IOMMU_DIRTY_PAGES_FLAG_START) {
- size_t pgsize;
- mutex_lock(&iommu->lock);
- pgsize = 1 << __ffs(iommu->pgsize_bitmap);
- if (!iommu->dirty_page_tracking) {
- ret = vfio_dma_bitmap_alloc_all(iommu, pgsize);
- if (!ret)
- iommu->dirty_page_tracking = true;
- }
- mutex_unlock(&iommu->lock);
- return ret;
- } else if (dirty.flags & VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP) {
- mutex_lock(&iommu->lock);
- if (iommu->dirty_page_tracking) {
- iommu->dirty_page_tracking = false;
- vfio_dma_bitmap_free_all(iommu);
- }
- mutex_unlock(&iommu->lock);
- return 0;
- } else if (dirty.flags & VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP) {
- struct vfio_iommu_type1_dirty_bitmap_get range;
- unsigned long pgshift;
- size_t data_size = dirty.argsz - minsz;
- size_t iommu_pgsize;
- if (!data_size || data_size < sizeof(range))
- return -EINVAL;
- if (copy_from_user(&range, (void __user *)(arg + minsz),
- sizeof(range)))
- return -EFAULT;
- if (range.iova + range.size < range.iova)
- return -EINVAL;
- if (!access_ok((void __user *)range.bitmap.data,
- range.bitmap.size))
- return -EINVAL;
- pgshift = __ffs(range.bitmap.pgsize);
- ret = verify_bitmap_size(range.size >> pgshift,
- range.bitmap.size);
- if (ret)
- return ret;
- mutex_lock(&iommu->lock);
- iommu_pgsize = (size_t)1 << __ffs(iommu->pgsize_bitmap);
- /* allow only smallest supported pgsize */
- if (range.bitmap.pgsize != iommu_pgsize) {
- ret = -EINVAL;
- goto out_unlock;
- }
- if (range.iova & (iommu_pgsize - 1)) {
- ret = -EINVAL;
- goto out_unlock;
- }
- if (!range.size || range.size & (iommu_pgsize - 1)) {
- ret = -EINVAL;
- goto out_unlock;
- }
- if (iommu->dirty_page_tracking)
- ret = vfio_iova_dirty_bitmap(range.bitmap.data,
- iommu, range.iova,
- range.size,
- range.bitmap.pgsize);
- else
- ret = -EINVAL;
- out_unlock:
- mutex_unlock(&iommu->lock);
- return ret;
- }
- return -EINVAL;
- }
- static long vfio_iommu_type1_ioctl(void *iommu_data,
- unsigned int cmd, unsigned long arg)
- {
- struct vfio_iommu *iommu = iommu_data;
- switch (cmd) {
- case VFIO_CHECK_EXTENSION:
- return vfio_iommu_type1_check_extension(iommu, arg);
- case VFIO_IOMMU_GET_INFO:
- return vfio_iommu_type1_get_info(iommu, arg);
- case VFIO_IOMMU_MAP_DMA:
- return vfio_iommu_type1_map_dma(iommu, arg);
- case VFIO_IOMMU_UNMAP_DMA:
- return vfio_iommu_type1_unmap_dma(iommu, arg);
- case VFIO_IOMMU_DIRTY_PAGES:
- return vfio_iommu_type1_dirty_pages(iommu, arg);
- default:
- return -ENOTTY;
- }
- }
- static int vfio_iommu_type1_register_notifier(void *iommu_data,
- unsigned long *events,
- struct notifier_block *nb)
- {
- struct vfio_iommu *iommu = iommu_data;
- /* clear known events */
- *events &= ~VFIO_IOMMU_NOTIFY_DMA_UNMAP;
- /* refuse to register if still events remaining */
- if (*events)
- return -EINVAL;
- return blocking_notifier_chain_register(&iommu->notifier, nb);
- }
- static int vfio_iommu_type1_unregister_notifier(void *iommu_data,
- struct notifier_block *nb)
- {
- struct vfio_iommu *iommu = iommu_data;
- return blocking_notifier_chain_unregister(&iommu->notifier, nb);
- }
- static int vfio_iommu_type1_dma_rw_chunk(struct vfio_iommu *iommu,
- dma_addr_t user_iova, void *data,
- size_t count, bool write,
- size_t *copied)
- {
- struct mm_struct *mm;
- unsigned long vaddr;
- struct vfio_dma *dma;
- bool kthread = current->mm == NULL;
- size_t offset;
- *copied = 0;
- dma = vfio_find_dma(iommu, user_iova, 1);
- if (!dma)
- return -EINVAL;
- if ((write && !(dma->prot & IOMMU_WRITE)) ||
- !(dma->prot & IOMMU_READ))
- return -EPERM;
- mm = get_task_mm(dma->task);
- if (!mm)
- return -EPERM;
- if (kthread)
- kthread_use_mm(mm);
- else if (current->mm != mm)
- goto out;
- offset = user_iova - dma->iova;
- if (count > dma->size - offset)
- count = dma->size - offset;
- vaddr = dma->vaddr + offset;
- if (write) {
- *copied = copy_to_user((void __user *)vaddr, data,
- count) ? 0 : count;
- if (*copied && iommu->dirty_page_tracking) {
- unsigned long pgshift = __ffs(iommu->pgsize_bitmap);
- /*
- * Bitmap populated with the smallest supported page
- * size
- */
- bitmap_set(dma->bitmap, offset >> pgshift,
- ((offset + *copied - 1) >> pgshift) -
- (offset >> pgshift) + 1);
- }
- } else
- *copied = copy_from_user(data, (void __user *)vaddr,
- count) ? 0 : count;
- if (kthread)
- kthread_unuse_mm(mm);
- out:
- mmput(mm);
- return *copied ? 0 : -EFAULT;
- }
- static int vfio_iommu_type1_dma_rw(void *iommu_data, dma_addr_t user_iova,
- void *data, size_t count, bool write)
- {
- struct vfio_iommu *iommu = iommu_data;
- int ret = 0;
- size_t done;
- mutex_lock(&iommu->lock);
- while (count > 0) {
- ret = vfio_iommu_type1_dma_rw_chunk(iommu, user_iova, data,
- count, write, &done);
- if (ret)
- break;
- count -= done;
- data += done;
- user_iova += done;
- }
- mutex_unlock(&iommu->lock);
- return ret;
- }
- static const struct vfio_iommu_driver_ops vfio_iommu_driver_ops_type1 = {
- .name = "vfio-iommu-type1",
- .owner = THIS_MODULE,
- .open = vfio_iommu_type1_open,
- .release = vfio_iommu_type1_release,
- .ioctl = vfio_iommu_type1_ioctl,
- .attach_group = vfio_iommu_type1_attach_group,
- .detach_group = vfio_iommu_type1_detach_group,
- .pin_pages = vfio_iommu_type1_pin_pages,
- .unpin_pages = vfio_iommu_type1_unpin_pages,
- .register_notifier = vfio_iommu_type1_register_notifier,
- .unregister_notifier = vfio_iommu_type1_unregister_notifier,
- .dma_rw = vfio_iommu_type1_dma_rw,
- };
- static int __init vfio_iommu_type1_init(void)
- {
- return vfio_register_iommu_driver(&vfio_iommu_driver_ops_type1);
- }
- static void __exit vfio_iommu_type1_cleanup(void)
- {
- vfio_unregister_iommu_driver(&vfio_iommu_driver_ops_type1);
- }
- module_init(vfio_iommu_type1_init);
- module_exit(vfio_iommu_type1_cleanup);
- MODULE_VERSION(DRIVER_VERSION);
- MODULE_LICENSE("GPL v2");
- MODULE_AUTHOR(DRIVER_AUTHOR);
- MODULE_DESCRIPTION(DRIVER_DESC);
|