diff options
author | Vasily Gorbik <gor@linux.ibm.com> | 2019-06-24 17:02:28 +0200 |
---|---|---|
committer | Vasily Gorbik <gor@linux.ibm.com> | 2019-06-24 17:02:28 +0200 |
commit | 9de31912490e967e148393c04fb054f0219b7350 (patch) | |
tree | 38423f36f2f4b9427d6fbd32f94ac58c9be31149 /drivers/s390 | |
parent | 96e5aaf914060a02955b09487e176769a75ae225 (diff) | |
parent | 5223bee837e8d90d752de744c5702706a7bb13d9 (diff) | |
download | linux-9de31912490e967e148393c04fb054f0219b7350.tar.bz2 |
Merge tag 'vfio-ccw-20190621' of https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/vfio-ccw into features
Refactoring of the vfio-ccw cp handling, simplifying the
code and avoiding unneeded allocating/copying.
* tag 'vfio-ccw-20190621' of https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/vfio-ccw:
vfio-ccw: Remove copy_ccw_from_iova()
vfio-ccw: Factor out the ccw0-to-ccw1 transition
vfio-ccw: Copy CCW data outside length calculation
vfio-ccw: Skip second copy of guest cp to host
vfio-ccw: Move guest_cp storage into common struct
s390/cio: Combine direct and indirect CCW paths
vfio-ccw: Rearrange IDAL allocation in direct CCW
vfio-ccw: Remove pfn_array_table
vfio-ccw: Adjust the first IDAW outside of the nested loops
vfio-ccw: Rearrange pfn_array and pfn_array_table arrays
s390/cio: Use generalized CCW handler in cp_init()
s390/cio: Generalize the TIC handler
s390/cio: Refactor the routine that handles TIC CCWs
s390/cio: Squash cp_free() and cp_unpin_free()
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Diffstat (limited to 'drivers/s390')
-rw-r--r-- | drivers/s390/cio/vfio_ccw_cp.c | 415 | ||||
-rw-r--r-- | drivers/s390/cio/vfio_ccw_cp.h | 7 | ||||
-rw-r--r-- | drivers/s390/cio/vfio_ccw_drv.c | 7 |
3 files changed, 151 insertions, 278 deletions
diff --git a/drivers/s390/cio/vfio_ccw_cp.c b/drivers/s390/cio/vfio_ccw_cp.c index f73cfcfdd032..9cddc1288059 100644 --- a/drivers/s390/cio/vfio_ccw_cp.c +++ b/drivers/s390/cio/vfio_ccw_cp.c @@ -16,12 +16,6 @@ #include "vfio_ccw_cp.h" -/* - * Max length for ccw chain. - * XXX: Limit to 256, need to check more? - */ -#define CCWCHAIN_LEN_MAX 256 - struct pfn_array { /* Starting guest physical I/O address. */ unsigned long pa_iova; @@ -33,11 +27,6 @@ struct pfn_array { int pa_nr; }; -struct pfn_array_table { - struct pfn_array *pat_pa; - int pat_nr; -}; - struct ccwchain { struct list_head next; struct ccw1 *ch_ccw; @@ -46,7 +35,7 @@ struct ccwchain { /* Count of the valid ccws in chain. */ int ch_len; /* Pinned PAGEs for the original data. */ - struct pfn_array_table *ch_pat; + struct pfn_array *ch_pa; }; /* @@ -139,55 +128,23 @@ static void pfn_array_unpin_free(struct pfn_array *pa, struct device *mdev) kfree(pa->pa_iova_pfn); } -static int pfn_array_table_init(struct pfn_array_table *pat, int nr) -{ - pat->pat_pa = kcalloc(nr, sizeof(*pat->pat_pa), GFP_KERNEL); - if (unlikely(ZERO_OR_NULL_PTR(pat->pat_pa))) { - pat->pat_nr = 0; - return -ENOMEM; - } - - pat->pat_nr = nr; - - return 0; -} - -static void pfn_array_table_unpin_free(struct pfn_array_table *pat, - struct device *mdev) +static bool pfn_array_iova_pinned(struct pfn_array *pa, unsigned long iova) { - int i; - - for (i = 0; i < pat->pat_nr; i++) - pfn_array_unpin_free(pat->pat_pa + i, mdev); - - if (pat->pat_nr) { - kfree(pat->pat_pa); - pat->pat_pa = NULL; - pat->pat_nr = 0; - } -} - -static bool pfn_array_table_iova_pinned(struct pfn_array_table *pat, - unsigned long iova) -{ - struct pfn_array *pa = pat->pat_pa; unsigned long iova_pfn = iova >> PAGE_SHIFT; - int i, j; + int i; - for (i = 0; i < pat->pat_nr; i++, pa++) - for (j = 0; j < pa->pa_nr; j++) - if (pa->pa_iova_pfn[j] == iova_pfn) - return true; + for (i = 0; i < pa->pa_nr; i++) + if (pa->pa_iova_pfn[i] == iova_pfn) + return true; return false; } -/* Create the list idal words for a pfn_array_table. */ -static inline void pfn_array_table_idal_create_words( - struct pfn_array_table *pat, +/* Create the list of IDAL words for a pfn_array. */ +static inline void pfn_array_idal_create_words( + struct pfn_array *pa, unsigned long *idaws) { - struct pfn_array *pa; - int i, j, k; + int i; /* * Idal words (execept the first one) rely on the memory being 4k @@ -196,19 +153,36 @@ static inline void pfn_array_table_idal_create_words( * there will be no problem here to simply use the phys to create an * idaw. */ - k = 0; - for (i = 0; i < pat->pat_nr; i++) { - pa = pat->pat_pa + i; - for (j = 0; j < pa->pa_nr; j++) { - idaws[k] = pa->pa_pfn[j] << PAGE_SHIFT; - if (k == 0) - idaws[k] += pa->pa_iova & (PAGE_SIZE - 1); - k++; + + for (i = 0; i < pa->pa_nr; i++) + idaws[i] = pa->pa_pfn[i] << PAGE_SHIFT; + + /* Adjust the first IDAW, since it may not start on a page boundary */ + idaws[0] += pa->pa_iova & (PAGE_SIZE - 1); +} + +void convert_ccw0_to_ccw1(struct ccw1 *source, unsigned long len) +{ + struct ccw0 ccw0; + struct ccw1 *pccw1 = source; + int i; + + for (i = 0; i < len; i++) { + ccw0 = *(struct ccw0 *)pccw1; + if ((pccw1->cmd_code & 0x0f) == CCW_CMD_TIC) { + pccw1->cmd_code = CCW_CMD_TIC; + pccw1->flags = 0; + pccw1->count = 0; + } else { + pccw1->cmd_code = ccw0.cmd_code; + pccw1->flags = ccw0.flags; + pccw1->count = ccw0.count; } + pccw1->cda = ccw0.cda; + pccw1++; } } - /* * Within the domain (@mdev), copy @n bytes from a guest physical * address (@iova) to a host physical address (@to). @@ -254,40 +228,6 @@ static long copy_from_iova(struct device *mdev, return l; } -static long copy_ccw_from_iova(struct channel_program *cp, - struct ccw1 *to, u64 iova, - unsigned long len) -{ - struct ccw0 ccw0; - struct ccw1 *pccw1; - int ret; - int i; - - ret = copy_from_iova(cp->mdev, to, iova, len * sizeof(struct ccw1)); - if (ret) - return ret; - - if (!cp->orb.cmd.fmt) { - pccw1 = to; - for (i = 0; i < len; i++) { - ccw0 = *(struct ccw0 *)pccw1; - if ((pccw1->cmd_code & 0x0f) == CCW_CMD_TIC) { - pccw1->cmd_code = CCW_CMD_TIC; - pccw1->flags = 0; - pccw1->count = 0; - } else { - pccw1->cmd_code = ccw0.cmd_code; - pccw1->flags = ccw0.flags; - pccw1->count = ccw0.count; - } - pccw1->cda = ccw0.cda; - pccw1++; - } - } - - return ret; -} - /* * Helpers to operate ccwchain. */ @@ -377,7 +317,7 @@ static struct ccwchain *ccwchain_alloc(struct channel_program *cp, int len) /* Make ccw address aligned to 8. */ size = ((sizeof(*chain) + 7L) & -8L) + sizeof(*chain->ch_ccw) * len + - sizeof(*chain->ch_pat) * len; + sizeof(*chain->ch_pa) * len; chain = kzalloc(size, GFP_DMA | GFP_KERNEL); if (!chain) return NULL; @@ -386,7 +326,7 @@ static struct ccwchain *ccwchain_alloc(struct channel_program *cp, int len) chain->ch_ccw = (struct ccw1 *)data; data = (u8 *)(chain->ch_ccw) + sizeof(*chain->ch_ccw) * len; - chain->ch_pat = (struct pfn_array_table *)data; + chain->ch_pa = (struct pfn_array *)data; chain->ch_len = len; @@ -412,23 +352,6 @@ static void ccwchain_cda_free(struct ccwchain *chain, int idx) kfree((void *)(u64)ccw->cda); } -/* Unpin the pages then free the memory resources. */ -static void cp_unpin_free(struct channel_program *cp) -{ - struct ccwchain *chain, *temp; - int i; - - cp->initialized = false; - list_for_each_entry_safe(chain, temp, &cp->ccwchain_list, next) { - for (i = 0; i < chain->ch_len; i++) { - pfn_array_table_unpin_free(chain->ch_pat + i, - cp->mdev); - ccwchain_cda_free(chain, i); - } - ccwchain_free(chain); - } -} - /** * ccwchain_calc_length - calculate the length of the ccw chain. * @iova: guest physical address of the target ccw chain @@ -444,25 +367,9 @@ static void cp_unpin_free(struct channel_program *cp) */ static int ccwchain_calc_length(u64 iova, struct channel_program *cp) { - struct ccw1 *ccw, *p; - int cnt; - - /* - * Copy current chain from guest to host kernel. - * Currently the chain length is limited to CCWCHAIN_LEN_MAX (256). - * So copying 2K is enough (safe). - */ - p = ccw = kcalloc(CCWCHAIN_LEN_MAX, sizeof(*ccw), GFP_KERNEL); - if (!ccw) - return -ENOMEM; - - cnt = copy_ccw_from_iova(cp, ccw, iova, CCWCHAIN_LEN_MAX); - if (cnt) { - kfree(ccw); - return cnt; - } + struct ccw1 *ccw = cp->guest_cp; + int cnt = 0; - cnt = 0; do { cnt++; @@ -471,10 +378,8 @@ static int ccwchain_calc_length(u64 iova, struct channel_program *cp) * orb specified one of the unsupported formats, we defer * checking for IDAWs in unsupported formats to here. */ - if ((!cp->orb.cmd.c64 || cp->orb.cmd.i2k) && ccw_is_idal(ccw)) { - kfree(p); + if ((!cp->orb.cmd.c64 || cp->orb.cmd.i2k) && ccw_is_idal(ccw)) return -EOPNOTSUPP; - } /* * We want to keep counting if the current CCW has the @@ -493,7 +398,6 @@ static int ccwchain_calc_length(u64 iova, struct channel_program *cp) if (cnt == CCWCHAIN_LEN_MAX + 1) cnt = -EINVAL; - kfree(p); return cnt; } @@ -514,17 +418,23 @@ static int tic_target_chain_exists(struct ccw1 *tic, struct channel_program *cp) static int ccwchain_loop_tic(struct ccwchain *chain, struct channel_program *cp); -static int ccwchain_handle_tic(struct ccw1 *tic, struct channel_program *cp) +static int ccwchain_handle_ccw(u32 cda, struct channel_program *cp) { struct ccwchain *chain; - int len, ret; + int len; - /* May transfer to an existing chain. */ - if (tic_target_chain_exists(tic, cp)) - return 0; + /* Copy 2K (the most we support today) of possible CCWs */ + len = copy_from_iova(cp->mdev, cp->guest_cp, cda, + CCWCHAIN_LEN_MAX * sizeof(struct ccw1)); + if (len) + return len; - /* Get chain length. */ - len = ccwchain_calc_length(tic->cda, cp); + /* Convert any Format-0 CCWs to Format-1 */ + if (!cp->orb.cmd.fmt) + convert_ccw0_to_ccw1(cp->guest_cp, len); + + /* Count the CCWs in the current chain */ + len = ccwchain_calc_length(cda, cp); if (len < 0) return len; @@ -532,14 +442,10 @@ static int ccwchain_handle_tic(struct ccw1 *tic, struct channel_program *cp) chain = ccwchain_alloc(cp, len); if (!chain) return -ENOMEM; - chain->ch_iova = tic->cda; + chain->ch_iova = cda; - /* Copy the new chain from user. */ - ret = copy_ccw_from_iova(cp, chain->ch_ccw, tic->cda, len); - if (ret) { - ccwchain_free(chain); - return ret; - } + /* Copy the actual CCWs into the new chain */ + memcpy(chain->ch_ccw, cp->guest_cp, len * sizeof(struct ccw1)); /* Loop for tics on this new chain. */ return ccwchain_loop_tic(chain, cp); @@ -557,7 +463,12 @@ static int ccwchain_loop_tic(struct ccwchain *chain, struct channel_program *cp) if (!ccw_is_tic(tic)) continue; - ret = ccwchain_handle_tic(tic, cp); + /* May transfer to an existing chain. */ + if (tic_target_chain_exists(tic, cp)) + continue; + + /* Build a ccwchain for the next segment */ + ret = ccwchain_handle_ccw(tic->cda, cp); if (ret) return ret; } @@ -590,131 +501,90 @@ static int ccwchain_fetch_direct(struct ccwchain *chain, struct channel_program *cp) { struct ccw1 *ccw; - struct pfn_array_table *pat; + struct pfn_array *pa; + u64 iova; unsigned long *idaws; int ret; int bytes = 1; - int idaw_nr = 1; + int idaw_nr, idal_len; + int i; ccw = chain->ch_ccw + idx; - if (ccw->count) { + if (ccw->count) bytes = ccw->count; - idaw_nr = idal_nr_words((void *)(u64)ccw->cda, ccw->count); - } - /* - * Pin data page(s) in memory. - * The number of pages actually is the count of the idaws which will be - * needed when translating a direct ccw to a idal ccw. - */ - pat = chain->ch_pat + idx; - ret = pfn_array_table_init(pat, 1); - if (ret) - goto out_init; - - ret = pfn_array_alloc(pat->pat_pa, ccw->cda, bytes); - if (ret < 0) - goto out_unpin; - - if (ccw_does_data_transfer(ccw)) { - ret = pfn_array_pin(pat->pat_pa, cp->mdev); - if (ret < 0) - goto out_unpin; + /* Calculate size of IDAL */ + if (ccw_is_idal(ccw)) { + /* Read first IDAW to see if it's 4K-aligned or not. */ + /* All subsequent IDAws will be 4K-aligned. */ + ret = copy_from_iova(cp->mdev, &iova, ccw->cda, sizeof(iova)); + if (ret) + return ret; } else { - pat->pat_pa->pa_nr = 0; + iova = ccw->cda; } + idaw_nr = idal_nr_words((void *)iova, bytes); + idal_len = idaw_nr * sizeof(*idaws); - /* Translate this direct ccw to a idal ccw. */ + /* Allocate an IDAL from host storage */ idaws = kcalloc(idaw_nr, sizeof(*idaws), GFP_DMA | GFP_KERNEL); if (!idaws) { ret = -ENOMEM; - goto out_unpin; - } - ccw->cda = (__u32) virt_to_phys(idaws); - ccw->flags |= CCW_FLAG_IDA; - - pfn_array_table_idal_create_words(pat, idaws); - - return 0; - -out_unpin: - pfn_array_table_unpin_free(pat, cp->mdev); -out_init: - ccw->cda = 0; - return ret; -} - -static int ccwchain_fetch_idal(struct ccwchain *chain, - int idx, - struct channel_program *cp) -{ - struct ccw1 *ccw; - struct pfn_array_table *pat; - struct pfn_array *pa; - unsigned long *idaws; - u64 idaw_iova; - unsigned int idaw_nr, idaw_len; - int i, ret; - int bytes = 1; - - ccw = chain->ch_ccw + idx; - - if (ccw->count) - bytes = ccw->count; - - /* Calculate size of idaws. */ - ret = copy_from_iova(cp->mdev, &idaw_iova, ccw->cda, sizeof(idaw_iova)); - if (ret) - return ret; - idaw_nr = idal_nr_words((void *)(idaw_iova), bytes); - idaw_len = idaw_nr * sizeof(*idaws); - - /* Pin data page(s) in memory. */ - pat = chain->ch_pat + idx; - ret = pfn_array_table_init(pat, idaw_nr); - if (ret) goto out_init; - - /* Translate idal ccw to use new allocated idaws. */ - idaws = kzalloc(idaw_len, GFP_DMA | GFP_KERNEL); - if (!idaws) { - ret = -ENOMEM; - goto out_unpin; } - ret = copy_from_iova(cp->mdev, idaws, ccw->cda, idaw_len); - if (ret) + /* + * Allocate an array of pfn's for pages to pin/translate. + * The number of pages is actually the count of the idaws + * required for the data transfer, since we only only support + * 4K IDAWs today. + */ + pa = chain->ch_pa + idx; + ret = pfn_array_alloc(pa, iova, bytes); + if (ret < 0) goto out_free_idaws; - ccw->cda = virt_to_phys(idaws); - - for (i = 0; i < idaw_nr; i++) { - idaw_iova = *(idaws + i); - pa = pat->pat_pa + i; - - ret = pfn_array_alloc(pa, idaw_iova, 1); - if (ret < 0) - goto out_free_idaws; + if (ccw_is_idal(ccw)) { + /* Copy guest IDAL into host IDAL */ + ret = copy_from_iova(cp->mdev, idaws, ccw->cda, idal_len); + if (ret) + goto out_unpin; - if (!ccw_does_data_transfer(ccw)) { - pa->pa_nr = 0; - continue; - } + /* + * Copy guest IDAWs into pfn_array, in case the memory they + * occupy is not contiguous. + */ + for (i = 0; i < idaw_nr; i++) + pa->pa_iova_pfn[i] = idaws[i] >> PAGE_SHIFT; + } else { + /* + * No action is required here; the iova addresses in pfn_array + * were initialized sequentially in pfn_array_alloc() beginning + * with the contents of ccw->cda. + */ + } + if (ccw_does_data_transfer(ccw)) { ret = pfn_array_pin(pa, cp->mdev); if (ret < 0) - goto out_free_idaws; + goto out_unpin; + } else { + pa->pa_nr = 0; } - pfn_array_table_idal_create_words(pat, idaws); + ccw->cda = (__u32) virt_to_phys(idaws); + ccw->flags |= CCW_FLAG_IDA; + + /* Populate the IDAL with pinned/translated addresses from pfn */ + pfn_array_idal_create_words(pa, idaws); return 0; +out_unpin: + pfn_array_unpin_free(pa, cp->mdev); out_free_idaws: kfree(idaws); -out_unpin: - pfn_array_table_unpin_free(pat, cp->mdev); out_init: ccw->cda = 0; return ret; @@ -735,9 +605,6 @@ static int ccwchain_fetch_one(struct ccwchain *chain, if (ccw_is_tic(ccw)) return ccwchain_fetch_tic(chain, idx, cp); - if (ccw_is_idal(ccw)) - return ccwchain_fetch_idal(chain, idx, cp); - return ccwchain_fetch_direct(chain, idx, cp); } @@ -760,9 +627,7 @@ static int ccwchain_fetch_one(struct ccwchain *chain, */ int cp_init(struct channel_program *cp, struct device *mdev, union orb *orb) { - u64 iova = orb->cmd.cpa; - struct ccwchain *chain; - int len, ret; + int ret; /* * XXX: @@ -775,28 +640,11 @@ int cp_init(struct channel_program *cp, struct device *mdev, union orb *orb) memcpy(&cp->orb, orb, sizeof(*orb)); cp->mdev = mdev; - /* Get chain length. */ - len = ccwchain_calc_length(iova, cp); - if (len < 0) - return len; - - /* Alloc mem for the head chain. */ - chain = ccwchain_alloc(cp, len); - if (!chain) - return -ENOMEM; - chain->ch_iova = iova; - - /* Copy the head chain from guest. */ - ret = copy_ccw_from_iova(cp, chain->ch_ccw, iova, len); - if (ret) { - ccwchain_free(chain); - return ret; - } - - /* Now loop for its TICs. */ - ret = ccwchain_loop_tic(chain, cp); + /* Build a ccwchain for the first CCW segment */ + ret = ccwchain_handle_ccw(orb->cmd.cpa, cp); if (ret) - cp_unpin_free(cp); + cp_free(cp); + /* It is safe to force: if not set but idals used * ccwchain_calc_length returns an error. */ @@ -819,8 +667,20 @@ int cp_init(struct channel_program *cp, struct device *mdev, union orb *orb) */ void cp_free(struct channel_program *cp) { - if (cp->initialized) - cp_unpin_free(cp); + struct ccwchain *chain, *temp; + int i; + + if (!cp->initialized) + return; + + cp->initialized = false; + list_for_each_entry_safe(chain, temp, &cp->ccwchain_list, next) { + for (i = 0; i < chain->ch_len; i++) { + pfn_array_unpin_free(chain->ch_pa + i, cp->mdev); + ccwchain_cda_free(chain, i); + } + ccwchain_free(chain); + } } /** @@ -992,8 +852,7 @@ bool cp_iova_pinned(struct channel_program *cp, u64 iova) list_for_each_entry(chain, &cp->ccwchain_list, next) { for (i = 0; i < chain->ch_len; i++) - if (pfn_array_table_iova_pinned(chain->ch_pat + i, - iova)) + if (pfn_array_iova_pinned(chain->ch_pa + i, iova)) return true; } diff --git a/drivers/s390/cio/vfio_ccw_cp.h b/drivers/s390/cio/vfio_ccw_cp.h index 3c20cd208da5..7cdc38049033 100644 --- a/drivers/s390/cio/vfio_ccw_cp.h +++ b/drivers/s390/cio/vfio_ccw_cp.h @@ -16,6 +16,12 @@ #include "orb.h" +/* + * Max length for ccw chain. + * XXX: Limit to 256, need to check more? + */ +#define CCWCHAIN_LEN_MAX 256 + /** * struct channel_program - manage information for channel program * @ccwchain_list: list head of ccwchains @@ -32,6 +38,7 @@ struct channel_program { union orb orb; struct device *mdev; bool initialized; + struct ccw1 *guest_cp; }; extern int cp_init(struct channel_program *cp, struct device *mdev, diff --git a/drivers/s390/cio/vfio_ccw_drv.c b/drivers/s390/cio/vfio_ccw_drv.c index 66a66ac1f3d1..34a9a5e3fd36 100644 --- a/drivers/s390/cio/vfio_ccw_drv.c +++ b/drivers/s390/cio/vfio_ccw_drv.c @@ -129,6 +129,11 @@ static int vfio_ccw_sch_probe(struct subchannel *sch) if (!private) return -ENOMEM; + private->cp.guest_cp = kcalloc(CCWCHAIN_LEN_MAX, sizeof(struct ccw1), + GFP_KERNEL); + if (!private->cp.guest_cp) + goto out_free; + private->io_region = kmem_cache_zalloc(vfio_ccw_io_region, GFP_KERNEL | GFP_DMA); if (!private->io_region) @@ -169,6 +174,7 @@ out_free: kmem_cache_free(vfio_ccw_cmd_region, private->cmd_region); if (private->io_region) kmem_cache_free(vfio_ccw_io_region, private->io_region); + kfree(private->cp.guest_cp); kfree(private); return ret; } @@ -185,6 +191,7 @@ static int vfio_ccw_sch_remove(struct subchannel *sch) kmem_cache_free(vfio_ccw_cmd_region, private->cmd_region); kmem_cache_free(vfio_ccw_io_region, private->io_region); + kfree(private->cp.guest_cp); kfree(private); return 0; |