diff --git a/arch/powerpc/include/asm/vas.h b/arch/powerpc/include/asm/vas.h index 6baf7b9ffed4f7..83afcb6c194b5c 100644 --- a/arch/powerpc/include/asm/vas.h +++ b/arch/powerpc/include/asm/vas.h @@ -36,6 +36,8 @@ /* vas mmap() */ /* Window is closed in the hypervisor due to lost credit */ #define VAS_WIN_NO_CRED_CLOSE 0x00000001 +/* Window is closed due to migration */ +#define VAS_WIN_MIGRATE_CLOSE 0x00000002 /* * Get/Set bit fields diff --git a/arch/powerpc/platforms/pseries/vas.c b/arch/powerpc/platforms/pseries/vas.c index 3bb219f5480674..fbcf311da0ec7b 100644 --- a/arch/powerpc/platforms/pseries/vas.c +++ b/arch/powerpc/platforms/pseries/vas.c @@ -457,11 +457,12 @@ static int vas_deallocate_window(struct vas_window *vwin) mutex_lock(&vas_pseries_mutex); /* * VAS window is already closed in the hypervisor when - * lost the credit. So just remove the entry from - * the list, remove task references and free vas_window + * lost the credit or with migration. So just remove the entry + * from the list, remove task references and free vas_window * struct. */ - if (win->vas_win.status & VAS_WIN_NO_CRED_CLOSE) { + if (!(win->vas_win.status & VAS_WIN_NO_CRED_CLOSE) && + !(win->vas_win.status & VAS_WIN_MIGRATE_CLOSE)) { rc = deallocate_free_window(win); if (rc) { mutex_unlock(&vas_pseries_mutex); @@ -578,12 +579,14 @@ static int __init get_vas_capabilities(u8 feat, enum vas_cop_feat_type type, * by setting the remapping to new paste address if the window is * active. */ -static int reconfig_open_windows(struct vas_caps *vcaps, int creds) +static int reconfig_open_windows(struct vas_caps *vcaps, int creds, + bool migrate) { long domain[PLPAR_HCALL9_BUFSIZE] = {VAS_DEFAULT_DOMAIN_ID}; struct vas_cop_feat_caps *caps = &vcaps->caps; struct pseries_vas_window *win = NULL, *tmp; int rc, mv_ents = 0; + int flag; /* * Nothing to do if there are no closed windows. @@ -602,8 +605,10 @@ static int reconfig_open_windows(struct vas_caps *vcaps, int creds) * (dedicated). If 1 core is added, this LPAR can have 20 more * credits. It means the kernel can reopen 20 windows. So move * 20 entries in the VAS windows lost and reopen next 20 windows. + * For partition migration, reopen all windows that are closed + * during resume. */ - if (vcaps->nr_close_wins > creds) + if ((vcaps->nr_close_wins > creds) && !migrate) mv_ents = vcaps->nr_close_wins - creds; list_for_each_entry_safe(win, tmp, &vcaps->list, win_list) { @@ -613,12 +618,35 @@ static int reconfig_open_windows(struct vas_caps *vcaps, int creds) mv_ents--; } + /* + * Open windows if they are closed only with migration or + * DLPAR (lost credit) before. + */ + if (migrate) + flag = VAS_WIN_MIGRATE_CLOSE; + else + flag = VAS_WIN_NO_CRED_CLOSE; + list_for_each_entry_safe_from(win, tmp, &vcaps->list, win_list) { + /* + * This window is closed with DLPAR and migration events. + * So reopen the window with the last event. + * The user space is not suspended with the current + * migration notifier. So the user space can issue DLPAR + * CPU hotplug while migration in progress. In this case + * this window will be opened with the last event. + */ + if ((win->vas_win.status & VAS_WIN_NO_CRED_CLOSE) && + (win->vas_win.status & VAS_WIN_MIGRATE_CLOSE)) { + win->vas_win.status &= ~flag; + continue; + } + /* * Nothing to do on this window if it is not closed - * with VAS_WIN_NO_CRED_CLOSE + * with this flag */ - if (!(win->vas_win.status & VAS_WIN_NO_CRED_CLOSE)) + if (!(win->vas_win.status & flag)) continue; rc = allocate_setup_window(win, (u64 *)&domain[0], @@ -634,7 +662,7 @@ static int reconfig_open_windows(struct vas_caps *vcaps, int creds) /* * Set window status to active */ - win->vas_win.status &= ~VAS_WIN_NO_CRED_CLOSE; + win->vas_win.status &= ~flag; mutex_unlock(&win->vas_win.task_ref.mmap_mutex); win->win_type = caps->win_type; if (!--vcaps->nr_close_wins) @@ -661,20 +689,32 @@ static int reconfig_open_windows(struct vas_caps *vcaps, int creds) * the user space to fall back to SW compression and manage with the * existing windows. */ -static int reconfig_close_windows(struct vas_caps *vcap, int excess_creds) +static int reconfig_close_windows(struct vas_caps *vcap, int excess_creds, + bool migrate) { struct pseries_vas_window *win, *tmp; struct vas_user_win_ref *task_ref; struct vm_area_struct *vma; - int rc = 0; + int rc = 0, flag; + + if (migrate) + flag = VAS_WIN_MIGRATE_CLOSE; + else + flag = VAS_WIN_NO_CRED_CLOSE; list_for_each_entry_safe(win, tmp, &vcap->list, win_list) { /* * This window is already closed due to lost credit - * before. Go for next window. + * or for migration before. Go for next window. + * For migration, nothing to do since this window + * closed for DLPAR and will be reopened even on + * the destination system with other DLPAR operation. */ - if (win->vas_win.status & VAS_WIN_NO_CRED_CLOSE) + if ((win->vas_win.status & VAS_WIN_MIGRATE_CLOSE) || + (win->vas_win.status & VAS_WIN_NO_CRED_CLOSE)) { + win->vas_win.status |= flag; continue; + } task_ref = &win->vas_win.task_ref; mutex_lock(&task_ref->mmap_mutex); @@ -683,7 +723,7 @@ static int reconfig_close_windows(struct vas_caps *vcap, int excess_creds) * Number of available credits are reduced, So select * and close windows. */ - win->vas_win.status |= VAS_WIN_NO_CRED_CLOSE; + win->vas_win.status |= flag; mmap_write_lock(task_ref->mm); /* @@ -706,12 +746,24 @@ static int reconfig_close_windows(struct vas_caps *vcap, int excess_creds) * later when the process issued with close(FD). */ rc = deallocate_free_window(win); - if (rc) + /* + * This failure is from the hypervisor. + * No way to stop migration for these failures. + * So ignore error and continue closing other windows. + */ + if (rc && !migrate) return rc; vcap->nr_close_wins++; - if (!--excess_creds) + /* + * For migration, do not depend on lpar_creds in case if + * mismatch with the hypervisor value (should not happen). + * So close all active windows in the list and will be + * reopened windows based on the new lpar_creds on the + * destination system during resume. + */ + if (!migrate && !--excess_creds) break; } @@ -761,7 +813,8 @@ int vas_reconfig_capabilties(u8 type) * target, reopen windows if they are closed due to * the previous DLPAR (core removal). */ - rc = reconfig_open_windows(vcaps, new_nr_creds - old_nr_creds); + rc = reconfig_open_windows(vcaps, new_nr_creds - old_nr_creds, + false); } else { /* * # active windows is more than new LPAR available @@ -771,7 +824,8 @@ int vas_reconfig_capabilties(u8 type) nr_active_wins = vcaps->nr_open_windows - vcaps->nr_close_wins; if (nr_active_wins > new_nr_creds) rc = reconfig_close_windows(vcaps, - nr_active_wins - new_nr_creds); + nr_active_wins - new_nr_creds, + false); } out: